WO2015088502A1

WO2015088502A1 - Polyurethane urea-containing compositions and optical articles and methods for preparing them

Info

Publication number: WO2015088502A1
Application number: PCT/US2013/074262
Authority: WO
Inventors: Nina V. Bojkova; Marvin J. Graham; Matthew J. Kryger; Federico Menta
Original assignee: Ppg Industries Ohio, Inc.
Priority date: 2012-12-13
Filing date: 2013-12-11
Publication date: 2015-06-18
Also published as: JP2019073737A; MY184863A; JP6408583B2; US20170153359A1; US9568643B2; PH12019500777A1; US20140171612A1; JP2017502119A; JP2017179386A; US9891349B2; US10012773B2; US20170235022A1

Abstract

A composition for the preparation of a transparent, non-elastomeric optical article is provided, the composition including: (1) a polyisocyanate component containing one or more different polyisocyanates; and (2) a component that is reactive with isocyanates, including: (a) optionally at least one polyol having a number average molecular weight greater than 500; (b) (i) at least one polyol and/or polythiol and (ii) at least one compound containing both amine and hydroxyl functional groups, wherein the compound (ii) has a number average molecular weight less than 500; and optionally (3) a urethanation catalyst. Multi-step and one-pot methods of preparing a cured, non-elastomeric polyurethane-containing optical article are also provided.

Description

POLYURETHANE UREA-CONTAINING COMPOSITIONS AND OPTICAL

ARTICLES AND METHODS FOR PREPARING THEM

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority from U.S. Provisional Patent Application No. 61/736,716, filed December 13, 2012, which is incorporated herein by reference in its entirety,

FIELD OF THE INVENTION

[0002] The present invention relates to cured, non-e!astomeric polyurethane urea- containing compositions and optical articles and methods of preparing them.

BACKGROUND OF THE INVENTION

[0003] Poiyurethane-containing materials such as poiyurethane-ureas have been developed as useful polymers in the manufacture of optical articles because of their excellent properties such as low birefringence, resilience, and chemical and impact resistance. They have been used in mold castings for lenses, glazings, and the like, Urea linkages in the polymers are particularly responsible for the superior thermai and mechanical properties such as hardness and stiffness. Aromatic polyamines have been used to prepare these urea-functional polymers. However, cost concerns are prompting searches for and development of alternative starting materials. Aliphatic polyamines tend to he highly reactive with isocyanate, making processing very difficult. New reaction methodology is necessary to allow for the use of readily available and inexpensive materials while still providing products with superior properties.

[0004] It would be desirable to provide a cost effective, straightforward method of preparing poiyurethane-containing optical articles that demonstrate outstanding properties. SUMMARY OF THE INVENTION

[0005] in accordance with the present invention, a composition for the preparation of a transparent, non-elastomeric optical article is provided. The composition comprises:

(1 ) a po!yisocyanate component comprising one or more different poiyisocyanates; and

(2) a component that is reactive with isocyanafes, comprising;

(a) optionaiiy, at ieast on poiyoi having a number average molecular weight greater than 500;

(b) (i) at Seas! one poiyoi and/or poiythioi and (ii) at least one compound containing both amine and hydroxyl functional groups, wherein the compound (ii) has a number average molecular weight less than 500; and optionaiiy

(3) a urethanation catalyst.

[0006] Also provided in a separate embodiment of the present invention is a separate composition for the preparation of a transparent, non-elastomeric optical article, the composition comprising:

(2) a component that is reactive with Isocyanafes, comprising:

(a) optionally at east one poiyoi having a number average molecular weight greater than 500;

(b) (i) at least one poiyoi and/or poiythioi and, optionally (ii) at ieast one compound containing both amine and hydroxy! functional groups, wherein the compound (ii) has a number average molecular weight less than 500; and

(c) a urea-containing diol reaction product of a reaction mixture substantially free of urethanation catalyst, the reaction mixture comprising a diisocyanate and at least one aliphatic compound containing both amine and hydroxyl functional groups, wherein the equivalent ratio of amine functional groups to isocyanate functional groups is at least 1 ; and optionally

(3) a urethanation catalyst.

[0Θ07^'| Methods of preparing a transparent, non-elastomeric optical article are also provided, one comprising: (1 ) combining to form a reaction mixture that is essentially free of urethanatlon catalysts:

(a) a polyisocyanate component comprising one or more different poiyisocyanates; and

(b) an active hydrogen component comprising at least one poiyoi and/or poiythtoi and at least one compound containing both amine and hydroxy! functional groups wherein the compound containing both amine and hydroxy! functional groups has the structure H₂N-L~OH, wherein L is a linear or branched alkyi, aryi, aralky!, or a!karyl chain which may contain hetero atoms;

(2) allowing the polyisocyanate component to react with amine functional groups in the active hydrogen component at a temperature and for a time sufficient to form an intermediate product comprising a polyuria prepolymer having hydroxy! functional groups in admixture with the po!yo! and/or poiyihio! and, optionally, the compound containing both amine and hydroxy! functional groups;

(3) mixing the intermediate product formed in step (2) with additional poiyisocyanates and optionally a urethanatlon catalyst to form a second reaction mixture;

(4) introducing the second reaction mixture formed in step (3) to a mold of a desired shape at a temperature and for a time sufficient to form a thermoset po!ymenzate; and

(5) releasing the po!yrnerizate from the mold to yield a transparent optical article.

(0098] Also provided in a separate embodiment of the present invention is a "single batch" or "one pot" method of preparing a transparent, non-elastomeric optical article comprising:

(1 ) combining to form a reaction mixture:

(b) an active hydrogen component comprising:

(b1 ) a first component that is essentially free of amino groups comprising at least one po!yo!; and

(D2) a second component comprising at least one polyol and/or polythiof and at least one compound containing both amine and hydroxyl functional groups and has the structure H₂N-L-OH, wherein L is a linear or branched aikyl, aryi, ara!kyl, or alkaryl chain which may contain hetero atoms, wherein the at least one po!yol has a number average molecular weight of 80 to 450;

(2) introducing the reaction mixture to a moid of a desired shape at a temperature and for a time sufficient to form a ihermoset polymerizate; and

(3) releasing the polymerizate from the mold to yield a transparent optical article.

[0009] In an additional embodiment of the present invention, a method of preparing a cured, non-elastomeric po!yurethane-coniaining optical article ts provided. The method comprises:

(1) combining to form a reaction mixture that is essentially free of urethanation catalysts:

(a) a polyisocyanate component comprising one or more different poiyssocyanates; and

(b) an active hydrogen component comprising at least one polyol and/or poiythiol and at least one compound containing both amine and hydroxy! functional groups wherein the compound containing both amine and hydroxy! functional groups is present in stoichiometric excess with respect to amine groups relative to isocyanate functional groups and has the structure h N-L-GH, wherein L is a linear or branched alkyl, aryi, aralky!, or alkaryl chain which may contain hetero atoms;

(2) allowing the polyisocyanate component to react with at least a portion of the amine functional groups in the active hydrogen component at a temperature and for a time sufficient to consume essentiall all of the isocyanate functional groups and form an intermediate product comprising a po!yurea prepoiymer having hydroxy! functional groups in admixture with the po!yol and the compound containing both amine and hydroxyl functional groups;

{3} mixing the intermediate product formed in step (2) with additional polyisocyanates and a urethanation catalyst to form a second reaction mixture;

(4) Introducing the second reaction mixture formed in step (3) to a moid of a desired shape at a temperature and for a time sufficient to form a ihermoset polymerizate; and

(5) releasing the polymerizate from the moid to yield a transparent optical (0010] In an additional embodiment of the present invention, method of preparing a cured, non-elastomeric poiyurethane-contafntng optica! article is provided. The method comprises:

{1 } combining to form a reaction mixture:

(a) a pofyisocyanate component comprising one or more different po!yisocyanates; and

(b) at feast one polyoi, wherein the poiyisocyanate component is present in stoichiometric excess relative to hydroxy! functional groups;

(2) allowing the components to react at a temperature and for a time sufficient to consume essentially all of the hydroxyl functional groups and form an intermediate product comprising a polyurethane prepolymer having isocyanate functional groups in admixture with excess poiyisocyanate;

(3) mixing the Intermediate product formed in step (2) with optionally an active hydrogen component comprising at least one polyoi and/or poiythiol, and at least one compound containing both amine and hydroxyl functional groups wherein the compound containing both amine and hydroxyl functional groups has the structure H₂N-L-OH, wherein L is a linear or branched alkyi, aryl, aralkyl, or alkaryl chain which may contain hetero atoms, to form a second reaction mixture;

(4) introducing the second reaction mixture formed in step (3) via injection to a moid of a desired shape at a temperature and for a time sufficient to form a thermoset po!ymerizate; and

(5) releasing the po!ymerizate from the mold to yield a transparent optical article.

DETAILED DESCRIPTION OF THE INVENTION

[0011] It is noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless expressly and unequivocally limited to one referent.

[0012] For the purposes of this specification, unless otherwise indicated, all numbers expressing quantities of ingredients, reaction conditions, and other parameters used in the specification and claims are to be understood as being modified In all instances by the term "about." Accordingly, unless indicated to the contrary, the numerical parameters set forth In the following specification and attached claims are approximations that may vary depending upon the desired properties to be obtained by the present invention. At the very least, and not a an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least; be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

jOO .3] Aii numerical ranges herein include ali numerical values and ranges of all numerical values within the recited numerical ranges. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth In the specific examples are reported as precisely as possible. Any numerical value, however, Inherently contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0014] The various embodiments and examples of the present invention as presented herein are each understood to be non-limiting with respect to the scope of the invention.

fOO!Sf As used In the following description and claims, the following terms have the indicated meanings:

| 016] The terms "acrylic" and "acryiate" are used interchangeably (unless to do so would alter the intended meaning) and Include acrylic acids, anhydrides, and derivatives thereof, such as their CrC₅ alky! esters, lower alkyl-substituted acrylic acids, e.g., C C₅ substituted acrylic acids, such as methacryiic acid, ethacrylic acid, etc., and their C1-C5 alky! esters, unless clearly indicated otherwise. The terms "(meth)acrylic" or "(meth)acrylate" are intended to cover both the acrylic/acrylate and methacrylic/methacryfate forms of the indicated material, e.g., a {meth)acrylate monomer.

|0O17] The term "cure", "cured" or similar terms, as used in connection with a cured or curable composition, e.g., a "cured composition" of some specific description, means that at least a portion of the pofymerizabie and/or crosslinkab!e components that form the curable composition is at least partially polymerized and/or crosslinked. The term "curable", as used for example in connection with a curable film-forming composition, means that the indicated composition is pofymerizabie or cross linkable, e.g., by means that include, but are not limited to, thermal, catalytic, electron beam, chemical free-radical initiation, and/or photoinitiation such as by exposure to ultraviolet light or other actinic radiation. In the context of the present invention, a "cured" composition may continue to be further curable depending on the availability of polymerizahle or Crosslin kabie components.

[€018] By "thermoset" is meant a polymer that irreversibly cures or crosslinks. Once solidified after curing, a thermoset polymer cannot be reheated and melted back to a liquid form, in contrast to a thermoplastic polymer.

I^'0019^'l The term "non-elasfomeric" refers to materials that do not exhibit typical e!astomeric behavior; i, e., they do not readily undergo reversible deformation or elongation to at least twice their original length.

[0020] The term "optical quality", as used for example in connection with polymeric materials, e.g., a "resin of optical quality" or "organic polymeric material of opticas quality" means that the Indicated material, e.g., a polymeric material, resin, or resin composition, is or forms a substrate, layer, film or coating that can be used as an optical article, such as an ophthalmic lens, or in combination with an optical article, because of its suitable optical properties,

(0021] The term "transparent", as used fo example in connection with a substrate, film, material and/or coating, means that the Indicated substrate, coating, film and/or material has the property of transmitting light without appreciable scattering so that objects lying beyond are entirely visible. As used herein, transparent articles demonstrate a light transmittance of at least 80%.

[0022] The composition of the present invention is suitable for the preparation of a transparent, non-elastomeric optical article, and comprises:

{1 } a polyisocyanate component comprising one or more different poiyisocyanates; and

(2) a component that is reactive with isocyanates, comprising:

(a) optionally at least one polyol having a number average molecular weight greater than 500;

(b) (I) at least one polyol and/or po!ythioi and (ii) at least one compound containing both amine and hydroxy! functional groups, wherein the compound (ii) has a number average molecular weight less than 500; and optionally (3) a urethanal!on catalyst. Note that each of components (2}(a) and (2)(b) may be present in an amount of 20 to 80 percent by weight, based on the total weight of resin solids in the component (2),

|0β23) Also provided in a separate embodiment of the present invention is a separate composition for the preparation of a transparent, non-elastomeric optical article, the composition comprising:

(1 ) a polyisocyanate component comprising one or more different polyisocyanates; and

(2) a component that is reactive with isocyanates, comprising:

(b) (i) at least one polyol and/or polythiol and, optionally (li) at least one compound containing both amine and hydroxy! functional groups, wherein the compound (ii) has a number average molecular weight less than 500; and

(c) a urea-containing diol reaction product of a reaction mixture substantially free of urethanation catalyst, the reaction mixture comprising a diisocyanafe and at least one aliphatic compound containing both amine and hydroxy! functional groups, wherein the equivalent ratio of amine functional groups to isocyanafe functional groups is at least 1 ; and optionally

(3) a urethanation catalyst. Again, each of components (2){a) and (2)(b) may be present in an amount of 20 to 80 percent by weight, based on the total weight of resin solids in the component (2).

{0024) Each of the components of the compositions above may be selected from those described in detail below with respect to the processes of the present invention.

[0025] According to the present invention, a method of preparing a cured, non- elastpmeric poiyurethane-containing optical article is provided. Optical articles prepared by the process of the present invention include, for example, camera lenses, ophthalmic articles such as piano (without optical power) and vision correcting (prescription) lenses (finished and semi-finished) including multifocal lenses (bifocal, trifocal, and progressive lenses); and ocular devices such as contact lenses and intraocular lenses, sun lenses, fashion lenses, sport masks, face shields and goggles. The optical article also may be chosen from glazings such as architectural windows and transparencies such as display screens, automobiie or aircraft windshields, and vehicular side windows.

[0026] in the first step of the method of the present invention, a reaction mixture is formed that is essentially free of urethanation catalysts. The reaction mixture is formed by combining (a) a polyisocyanate component and (h) an active hydrogen component.

|0027| The polyisocyanate component comprises one or more different polyisocyanates. Polyisocyanates useful in the first component are numerous and widely varied. Non-limiting examples can include aliphatic polyisocyanates, cycioaliphatic polyisocyanates wherein one or more of the isocyanato groups are attached directly to the cycloailphatic ring, cycioaliphatic polyisocyanates wherein one or more of the isocyanato groups are not attached directly to the cycioaliphatic ring, aromatic polyisocyanates wherein one or more of the isocyanato groups are attached directl to the aromatic ring, and aromatic polyisocyanates wherein one or more of the Isocyanato groups are not attached directly to the aromatic ring, and mixtures thereof. When an aromatic polyisocyanate is used, generally care should be taken to select a material that does not cause the polyurethane-contalning polymer to color (e.g., yellow).

[0028] The polyisocyanate can include but is not limited to aliphatic or cycioaliphatic diisocyanates, aromatic diisocyanates, cyclic dimers and cyclic trimers thereof, and mixtures thereof. Non-limiting examples of suitable polyisocyanates can include Desmodur N 3300 (hexamethylene diisocyanate trimer) which is commercially available from Bayer; Desmodur N 3400 (80% hexamethylene diisocyanate dimer and 40% hexamethylene diisocyanate trimer), In a non-limiting embodiment, the polyisocyanate can inciude dicyclohexylmethane diisocyanate and isomeric mixtures thereof. As used herein and the claims, the term 'isomeric mixtures" refers to a mixture of the cis-cis, trans-trans, and/or cis-trans isomers of the polyisocyanate. Non-limiting examples of isomeric mixtures for use In the present Invention can include the trans-trans isomer of 4_!4^,-methylenebls(cyclohexyl isocyanate), hereinafter referred to as "PI CM" (paraisocyanato cyclohexylmethane), the cis-trans isomer of PICM, the cis-cis isomer of PI CM, and mixtures thereof. [0029] Suitable isomers for use in the present invention include but are not limited to the following three isomers of 4.4 '~methyienebis(cyciohexyi isocyanate), also known as dicyciohexyimethane diisocyanate.

\

\ CH₂ /

OCN NCO

NCO

CH, /

/ NCO

cis , trans

CIS, CIS

[0030] PICM can be prepared by phosgenafrng 4,4^,-methy!enebis{cyclohexyl amine) (PACM) by procedures well known in the art such as the procedures disclosed In United States Patents 2,844,007; 2,680,127 and 2,908,7_.03; which are incorporated herein by reference. The PAC isomer mixtures, upon phosgenation, can produce PiCM in a liquid phase, a partially liquid phase, or a solid phase at room temperature. Alternatively., the PACM isomer mixtures can be obtained by the hydrogenatton of methyienedianiline and/or by fractional crystallization of PACM isomer mixtures in the presence of -water and alcohols such as methanol and ethanol.

Additional aliphatic and cycloaBphatic dissocyanates that can he used include hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, diphenylmethane- 4,4'-diisocyanate, S-isocyanato-methy!-SAS-tnmethyi cyclohexyl-isocyanate ("IPDI") which is commercially available from Arco Chemical, m-xylylene diisocyanate (" XDi") and meta-tetramethylxylylene diisocyanate ( 1 ,3-bis( 1 -isocyanato-1 - methyi8thyi)-berizene) which is commercially available from Cytec Industries Inc. under the trade name T XDI® ( eta.) Aliphatic Isocyanate. [003 ί] As used herein and the claims, the term "aliphatic and cy oaiiphaiic diisocyanates" refers to 8 to 100 carbon atoms linked in a straight chain or cyclized having two isocyanate reactive end groups. In a non-limiting embodiment of the present invention, the aliphatic and cycloaiiphatic diisocyanates for use in the present invention can include !PDl and compounds of the formula R~(NCO>2 wherein R represents an aliphatic group or a cycioaiiphatic group,

[0032] In a particular embodiment of the present invention, the pofyisocyanate component comprises isophorone diisocyanaie, dicyciohexylmethane diisocyanate, bexamethyiene diisocyanate, diphenyimeihane-4,4'-diisocyanate, meta- tetrametriyixylyiene diisocyanate, (1 ,3-bis{1 -isocyanato-1 -methytethyl)- benzene}, and/or meta-xylyiene diisocyanate.

[003 f The active hydrogen component (b) used to form the reaction mixture comprises at least one polyoi and/or poiythiol and at least one compound containing both amine and hydroxy! functional groups (i. e., an amino alcohol}. In certain embodiments the active hydrogen component (b) used to form the reaction mixture comprises at least two poiyois and at least one amino alcohol,

[Θ034] In particular embodiments of the present invention the reaction mixture is essentially free of compounds containing both amino and aromatic functional groups wherein the amino groups are attached directly to the aromatic ring. The reaction mixture may also be essentially free of po!yamines. Typically, the amino alcohol is aliphatic.

[0035] Suitable polyols can include but are not limited to polyether poiyois, polyester poiyois, polycapro!actone poiyois, polycarbonate polyols, and mixtures thereof. onomeric polyols such as butanediol, 1 ,6-hexanediol, Bisphenol A and the like, or other higher polyols such as trimethylolprppane, pentaerythritoi, and the like, and any of the low molecular weight diols or glycols listed below are also suitable. At least one of the polyols in the active hydrogen component may contain aromatic functionality. It is believed that the use of aromatic polyols increases the refractive index (Rl) of the optical article being prepared. However, it is preferred that when at least one of the polyols is an aromatic ring-containing polyoi, the hydroxy! groups in the polyoi are not directly bonded to aromatic ring; i. e., the aromatic poiyois are not phenolic, 10036] Examples of poiyether poiyols are polyalkylene ether poiyois which include those having the following structural formula:

where the substituent R1 is hydrogen or lower alkyi containing from 1 to 5 carbon atoms including mixed subststuents, and n is typically from 2 to 6 and m is from 8 to 100 or higher, included are poiy(oxytetramethylene) glycols, poly(oxytetraethyiene) glycols, poly(oxy-1 ,2-propyiene) glycols, and poly(oxy~1 ,2-butyiene) glycols. Non- limiting examples of alkylene oxides can include ethylene oxide, propylene oxide, butylene oxide, amylene oxide, aralky!ene oxides, such as but not limited to styrene oxide, mixtures of ethylene oxide and propylene oxide. In a further non-limiting embodiment, po!yoxya!kyiene poiyols can be prepared with mixtures of alkylene oxide using random or step-wise oxyaikylation,

[ΌΘ37] Also useful are poiyether poiyols formed from oxyaikylation of various poiyols, for example, diois such as ethylene glycol, 1 ,6-hexanediol, Bisphenol A and the like, or other higher poiyols such as trimethylolpropane, pentaerythritol, and the like, Poiyols of higher functionality which can be utilized as indicated can be made, for instance, by oxyaikylation of compounds such as sucrose or sorbitol. One commonly utilized oxyaikylation method is reaction of a polyoi with an alkylene oxide, for example, propylene or ethylene oxide, in the presence of an acidic or basic catalyst. Particular polyethers include those sold under the names TERATHANE and TERACOL, available from E. i. Du Pont de Nemours and Company, Inc., and POLY EG, available from Q O Chemicals, Inc., a subsidiary of Great Lakes Chemical Corp,

|0038] Poiyether glycols for use in the present invention can include but are not limited to poiytetramethylene ether glycol. [0039] The poiyether-containing polyol can comprise block copolymers including blocks of ethylene oxide-propyiene oxide and/or ethylene oxide-butyiene oxide. Pluronic R, Pluronsc L82D, Teironic R and Tetronic, which are commercially available from BASF, can be used as the poiyether-containing poiyoi material in the present invention.

[0040| Suitable polyester glycols can include but are not limited to the esterification products of one or more dicarboxyiic acids having from four to ten carbon atoms, such as adipic, succinic or sebacic acids, with one or more low molecular weight glycols or diols having from two to ten carbon atoms, such as ethylene glycol, propylene glycol, diethyiene glycol, 1 ,4-butanediol, neopentyl glycol, 1 ,8-hexanediol and 1 ,10-decanediol. In a non-limiting embodiment, the polyester glycols can be the esterification products of adipic acid with diols of from two to ten carbon atoms.

[0041] Suitable poiycaprolactone glycols for use in the present invention can include the reaction products of E-caprolactone with one or more of the low molecular weight glycols listed above. A poiycaprolactone may be prepared by condensing caproiactone in the presence of a difunctional actsve hydrogen compound such as water or at least one of the low molecular weight glycols listed above. Particular examples of poiycaprolactone glycols include poiycaprolactone poiyesterdiois available as CAPA® 2047 and CAPA® 2077 from Solvay Corp.

[0042] Polycarbonate polyols are known in the art and are commercially available such as Ravecarb^{1 M} 107 (Enichem S.p.A.}. In a non-limiting embodiment, the polycarbonate polyol can be produced by reacting an organic glycol such as a diol and a diaikyl carbonate, such as described in United States Patent 4,160,853, In a non-limiting embodiment, the poiyoi can include po!yhexamethy! carbonate having varying degrees of polymerization.

|0fJ43| The glycol material can comprise low molecular weight polyo!s such as polyols having a molecular weight of Jess than 500, and compatible mixtures thereof. As used herein, the term "compatible" means that the glycols are mutually soluble in each other so as to form a single phase. Non-limiting examples of these polyols can include tow molecular weight diols and triols. If used, the amount of trioi is chosen so as to avoid a high degree of cross-linking in the polyureihane. A high degree of cross-linking can result in a curable po!yurethane that is not formable by moderate heat and pressure. The organic glycoi typically contains from 2 to 16, or from 2 to 6, or from 2 to 10, carbon atoms. Non-limiting examples of such glycols and other polyofs can Include ethylene glycol, propylene glycol, diethylene glycol, triethyiene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, 1 ,2-, 1 ,3- and 1 ,4- butanediol, 2,2,4 ri eihyl-1 ,3-penianediol_J 2-methyl-t ,3-pentanedioi, 1 ,3- 2,4- and 1 ,5-pentanediol, 2,5- and 1 ,6-hexanediol, 2,4-heptanediol, 2-ethyi~1 ,3-hexanediol, 2,2-dimethyi-1 ,3-propanediol, 1 ,8-ocianediol, 1 ,9-nonanediol, 1 ,10-decanedioi, 1 ,4- cyclohexanedioL 1 ,4-cyclohexanedimethanoi, 1 ,2-bis{hydroxyethyi)-cyclohexane, glycerin, tetramethylolmeihane, such as but not limited to pentaerythriiol, trimeihylo!ethane and tri eihyiolpropane; and isomers thereof,

|0O 4] The polyol can have a weight average molecular weight, for example, of at least 60, or at least 90, or at least 200. Additionally, She polyol can have a weight average molecular weight, for example, of less than 10,000, or less than 7000, or less than 5000, or less than 2000.

10045] The polyol for use in the present invention can include teresters produced from at least one low molecular weight dicarboxyiic acid, such as adipic acid,

[00 61 Polyester glycols and polycaprolactone glycols for use in the present invention can be prepared using known esierification or transesierification procedures as described, for example, in the article D. Svl. Young, F, Hostettler et ai., "Polyesters from Lactone," Union Carbide F-40, p. 147.

0047J Polyester glycols can also be prepared from the reaction of 1 ,6-hexanediol and adipic acid; 1 ,10-decandioi and adipic acid; or 1 ,10-decanediol and ca pro lactone.

[0048] Thioi-GontainSng materials may be present in the active hydrogen component and may be used to produce a prepolymer such as a sulfur-containing isocyanate- functional polyurethane for the preparation of high Index poiyurethane-containing films; I. e., films having a relatively high refractive index. Note thai in these embodiments the polyurethane prepolymer used as the first component may contain disulfide linkages due to disulfide linkages contained In the polythiol and/or poi.ythiol oligomer used to prepare the polyurethane prepolymer.

[0049] Thiol-containing materials may have at least: two thiol functional groups and may comprise a dithio!, or a mixture of a dithiof and a compound having more than two thiol functional groups (higher pol thio!). Such mixtures may include mixtures of dithiols and/or mixtures of higher po!yth!o!s. The thiol functional groups are typically terminal groups, though a minor portion (i. e,, less than 50 percent of all groups) may be pendant along a chain. The compound (a) may additionally contain a minor portion of other active hydrogen functionality (i. e., different from thiol), for example, hydroxy! functionality. Thiol-containing materials may be linear or branched, and may contain cyclic, alkyl, aryl, aralkyi, or alkaryl groups.

[00501 Thiol-containing materials may be selected so as to produce a substantially linear oiigomeric polytbiol. Therefore, the material comprises a mixture of a dithioi and a compound having more than two thiol functional groups, the compound having more than two thiol functional groups can be present In an amount up to 10 percent by weigh! of the mixture,

[0051] Suitable dithiols can include linear or branched aliphatic, cyc!oaiiphatic, aromatic, heterocyclic, polymeric, oiigomeric dithiols and mixtures thereof. The dithioi can comprise a variety of linkages Including but not limited to ether linkages (~ 0-), sulfide linkages (-S-), polysulfide linkages {-S_x-, wherein x is at least 2, or from 2 to 4) and combinations of such linkages.

[0052] Non-limiting examples of suitable, dithiols for use in the present invention can include but are not limited to 2₎5~dimercaptomeihyi~1 _s4~dithiane,

dimercaptodiethylsu!fide (DMDS), ethanedithiol, 3,6-dioxa-1 ,8-octanedithiol, ethylene glycol di(2-mercaptoacetate), ethylene glycol di(3-rnercaptopropionaie),

po.ly(ethylene glycol) di(2-mercaptoacetate) and poly{ ethylene glycol) di{3- mercaptopropionate), benzenedithiol, 4-tert^«butyM ,2-benzenedithioi, 4,4'^»

thiodibenzenethiol, and mixtures thereof,

[0053] The dithioi may include dithioi oligomers having disulfide linkages such as materials represented b the following formula:

|0054j Dithioi oligomers represented by Formula I can be prepared, for example, by the reaction of 2_f5-dimeracaptomet y!-1 ,4-diihiane with sulfur in the presence of basic catalyst, as known in the art.

[0055] The nature of the SH group in polythiois is such that oxidative coupling can occur readily, leading to formation of disulfide linkages. Various oxidizing agents can lead to such oxidative coupling. The oxygen In the air can in some cases lead to such oxidative coupling during storage of the poiythioL It is believed that a possible mechanism for the oxidative coupling of thiol groups involves the formation of thlyi radicals, followed by coupling of said thlyi radicals, to form disulfide linkage. It is further believed that formation of disulfide linkage can occur under conditions that can lead to the formation of thiyl radical, including but not limited to reaction conditions involving free radical initiation. The polythiois can include species containing disulfide linkages formed during storage.

[0056] The polythiois for use in materia! (II) in the preparation of the polyurethane material in the first component can also include species containing disulfide linkages formed during synthesis of the polythioi.

[0057] In certain embodiments, the dithioi for use in the present invention, can include at least one dithioi represented by the following structural formulas:

( IV)

100581 The suffide-containing diihiois comprising 1 ,3-dithiolane (e.g., formulas II and ill) or 1 ,3-dithiane (e.g., formulas IV and V) can be prepared by reacting asym- dichioroacetone with dimercaptan, and then reacting the reaction product with dimercaptoalkylsuifide, dimercaptan or mixtures thereof, as described in U. S. Patent 7,009,032 82.

f0059f Non-limiting examples of suitable dimercaptans for use in the reaction with asym-dichioroacetone can include but are not limited to materials represented by the following formula x

VI

wherein Y can represent CH₂ or (CH₂-S-CH₂}, and n can be an integer from 0 to 5. The dimercaptan for reaction with asym-dichioroacetone in the present invention can be chosen from, for example, ethanedithiof, propanediol, and mixtures thereof. [00601 The amount of asym-d ichloroacetone and dimercapian suitable for carrying out the above reaction can vary. For example, asym-dichloroacetone and dimercapian can be present in the reaction mixture in an amount such that the molar ratio of dichtoroacetone to dimercapian can be from 1 :1 to 1.'10.

[0061] Suitable temperatures for reacting asym-dichloroacetone with dimercapian can vary, often ranging from 0 to 100°C.

|0O62] Non-limiting examples of suitable dimercaptans for use in the reaction with the reaction product of the asym-dichloroacetone and dimercaptan, can include but are not limited to matenais represented by the above general formula VI, aromatic dimercaptans, cyc!oa!ky! dimercaptans, heterocyclic dimercaptans, branched dimercaptans, and mixtures thereof.

[0063] Non-limiting examples of suitable dimercaptoalky!sulfides for use in the reaction with the reaction product of the asym-dichloroacetone and dimercaptan, can include materials represented by the following formula:

VII

wherein X can represent Q, S or Se, n can be an integer from 0 to 10, m can be an integer from 0 to 10, p can be an integer from 1 to 10, q can be an integer from 0 to 3, and with the proviso that (m + n) is an integer from 1 to 20.

[00641 Non-limiting examples of suitable dimercapioalkyisulfides for use in the present invention can include branched dimercaptoalkylsuifides,

[0065] The amount of dimercaptan, dimercaptoa!kyisu!fide, or mixtures thereof, suitable for reacting with the reaction product of asym-dichloroacetone and dimercaptan, can vary. Typically, dimercaptan, dimercaptoalkylsulflde, or a mixture thereof, can be present in the reaction mixture in an amount such that the equivalent rafio of reaction product to dimercaptan, dimercaptoalkylsulflde, or a mixture thereof, can be from 1 :1.01 to 1 :2. Moreover, suitable temperatures for carrying out this reaction can vary within the range of from 0 to 100°C.

(_.0066] The reaction of asym-dichloroacetone with dimercaptan can be carried out in the presence of an acid catalyst, The acid catalyst can be selected from a wide variety known in the art, such as but not limited to Lewis acids and Bronsted acids. Non-limiting examples of suitable acid catalysts can include those described in UlimanrVs Encyclopedia of industrial Chemistry, 5^th Edition, 1992, Volume A21 , pp. 673 to 674. The acid catalyst Is often chosen from boron trifluoride etheraie, hydrogen chloride, to!uenesulfonic acid, and mixtures thereof. The amount of acid catalyst can vary from 0.01 to 10 percent by weight of the reaction mixture,

0O67| The reaction product of asym-dichioroacetone and dimercapian can alternatively be reacted with dirnercaptoalkyisuifide, dimercaptan or mixtures thereof, in the presence of a base. The base can be selected from a wide variety known in the art, such as but not limited to Lewis bases and Bronsted bases. Non-limiting examples of suitable bases can include those described in Ullmann's Encyclopedia of Industrial Chemistry, 5^th Edition, 1992, Volume A21 , pp. 673 to 674, The base Is often sodium hydroxide. The amount of base can vary. Typically, a suitable equivalent ratio of base to reaction product of the first reaction, can be from 1 :1 to 10:1.

[0068] The reaction of asym-dichjoroacetone with dimercaptan can be carried out in the presence of a solvent. The solvent can be selected from but is not limited to organic solvents. Non-limiting examples of suitable solvents can include but are not limited to chloroform, dichloromethane, 1 ,2-dich!oroethane, diethyl ether, benzene, toluene, acetic acid and mixtures thereof,

[0069] In another embodiment, the reaction product of asym-dichioroacetone and dimercaptan can be reacted with dirnercaptoalkyisuifide, dimercaptan or mixtures thereof, with or without the presence of a solvent, wherein the solvent can be selected from but Is not limited to organic solvents. Non-limiting examples of suitable organic solvents can include alcohols such as but not limited to methanol, etnanol and propanoi; aromatic hydrocarbon solvents such as but not limited to benzene, toluene, xylene; ketones such as but not limited to methyl ethyl ketone; water: and mixtures thereof,

[0070] The reaction of asym-dichioroacetone with dimercaptan can also be carried out in the presence of a dehydrating reagent. The dehydrating reagent can be selected from a wide variety known in the art. Suitable dehydrating reagents for use in this reaction can include but are not limited to magnesium sulfate, The amount of dehydrating reagent can vary widely according to the stoichiometry of the dehydrating reaction.

|0071] The polythiois for use in material (ii) in the preparation of the polyureihane material in the first component can be prepared in certain non-limiting embodiments by reacting 2~meihyi-2~dichioromethyl-1 ₎3~dithiolane with dimercaptodiethyisulfide to produce dimercapto-1 ,3-dithioiane derivative of formula iil. Alternatively, 2-methyl~2- dichioromethyl-1 ,3-dithiolane can be reacted with 1 ,2-eihanedithioi to produce dimercapto-1 ,3-dithiolane derivative of formula IK 2~meihyj~2-dichloromethyM ,3- dithiane can he reacted with dimercaptodiethyisulfide to produce dimercapto.-1 ,3- dit iane derivative of formula V. Also, 2~methyi-2-dich!oromethy1-1 ,3-dithiane can be reacted with 1 ^' ,2-ethanedifhio! to produce dimercapto-1 ,3-dithiane derivative of formula IV.

|0072] Another non-limiting example of a dithioi suitable for use as the material (ii) can include at least one dithioi oligomer prepared by reacting dichloro derivative with dimercaptoalkylsulfide as follows:

wherein R can represent CH₃, CH3CO, Gi to C10 alky!, cycloaikyl, ary! a!kyi, or a!ky!- CO; Y can represent Ci to C10 alky!, cycloaikyl, C₆ to C aryl, (CH2)_p(S)_m(CH2)_q, (CH2)p(Se)rr_s(CH₂)_ai (CH2)p(Te)„,{CH2)q wherein m can be an integer from 1 to 5 and, p and q can each be an integer from 1 to 10; n can be an integer from 1 to 20; and x can be an integer from 0 to 10.

[0073] The reaction of dichloro derivative with dimercaptoalkylsulfide can be carried out in the presence of a base. Suitable bases include any known to those skilled in the art in addition to those disclosed above.

[0074] The reaction of dichloro derivative with dimercaptoalkylsulfide may be carried out in the presence of a phase transfer catalyst. Suitable phase transfer catalysts for use in the present invention are known and varied. Non-limiting examples can Include but are not limited to fetraa!kylammonium salts and tetraalkyiphosphomum salts. This reaction is often carried out in the presence of tetrabufylphosphonium bromide as phase transfer catalyst. The amount of phase transfer catalyst can vary

:ø- widely, from 0 to 50 equivalent percent, or from 0 to 10 equivalent percent, or from 0 to 5 equivalent percent, relative to the dimercaptosuifSde reactants,

|0075| The ppiythiois for use in material (ii) may further contain hydroxy! functionality. Non-limiting examples of suitable materials having both hydroxy! and multiple (more than one) thiol groups can include but are not limited to glycerin bis(2- mereaptoacetate), glycerin his(3-mercaptopropionate}, 1 ,3-dimercapto-2-propanoi, 2_!3-dimercapto-1~propanol, trimethylo!propane bis(2~mercaptoacetate),

trimethyfoipropane bis(3-mereaptopropionafe), pentaerythritoi bis{2~

mercaptoacetate), pentaerythritoi tns(2-mercaptoacetate), pentaerythritoi bis(3~ mercaptopropionate), pentaerythritoi tris(3-mercaptopropionate), and mixtures thereof,

[0076] In addition to dithiois disclosed above, particular examples of suitable diihiols can include 1 ,2-eihanedithiol, 1 ,2-propanedithiol, 1 ,3-propanedithiol, 1 ,3- butanedithiol, 1 ₍4~butanediihioi, 2,3-butanedit ioi, 1 ,3-pentanedithiol, 1 ,5- pentanedithioi, 1 ,6-hexaneditbiol, 1 ,3-dimercapio-3-methyi butane,

dipentenedimercaptan, ethylcyclohexyid fthiol {ECHDT), dimercaptod iethy!suif ide (DMDS), methyl-substituted d imercaptodiethylsulfide, dimethyl-substituted

dimercaptodietbylsulfide, 3,6-dioxa-1 ,8~octanedithloL 1 ,5-dimercapto-3-oxapentane, 2,5-dimercaptomethyl-1 ,4-dithiane (DMMD), ethylene glycol di(2-mercaptoacetafe), ethylene glycol di{3-mercaptopropionate), and mixtures thereof,

[0077] Suitable trifunctional or higher-functional polythlols for use in material (ii) can be selected from a wide variety known in the art. Non-limiting examples can include pentaerythritoi tetrakis(2-mercaptoacetate), pentaerythritoi teirakss(3- mercaptopropionate), trimeihyioipropane tris(2-mercaptoacetate), trimeihyioipropane tris(3~mercaptopropionate), and/or thioglycero! bis(2~mercaptoacetate).

[0078] For example, the polythioi can be chosen from materials represented by the following general formula,

wherein Ri and i¾ can each be independently chosen from straight or branched chain aikylene, cyclic aiky!ene, phenyiene and C1-C9 a!kyl substituted phenyiene. Non-limiting examples of straight or branched chain alky!ene can Include methylene, ethylene, 1 ,3-propy!ene, 1 ,2-propytene, 1 ,4-butylene, 1 ,2-butylene, penty!ene, hexytene, epfylene, octylene, nonyiene, decy!ene, undecylene, octadeeyiene and icosyiene. Non-limiting examples of cyclic alkylenes can include cyciopentylene, cyclohexyiene, cyciohepiyiene, cyciooctylene, and alkyl-subsfltuted derivatives thereof. The divalent linking groups Ri and R₂ can he chosen from methylene, ethylene, phenyiene, and alkyi-substituted phenyiene, such as methyl, ethyl, propyl, isopropyf and nony! substituted phenyiene.

|§079| In particular embodiments, a poiythiol may be prepared by reacting together (1 ) any of the dithiols mentioned above, and (2) a compound having at least two double bonds (for example, a diene) or a compound having a triple bond, such as propargyl alcohol.

fH SOj The compound (2) having at least two double bonds can be chosen from non- cyclic dienes, including straight chain and/or branched aliphatic non-cyclic dienes, non-aromatic hng-containlng dienes, including non-aromatic ring-containing dienes wherein the double bonds can be contained within the ring or not contained within the ring or any combination thereof, and wherein the non-aromatic ring-containing dienes can contain non-aromatic monocyclic groups or non-aromatic polycyclic groups or combinations thereof; aromatic ring-containing dienes; or heterocyclic ring- containing dienes; or dienes containing any combination of such non-cyclic and/or cyclic groups. The dienes can optionally contain thioefher, disulfide, poiysuifide, suifone, ester, thioester, carbonate, thiocarbonate, urethane, or thiourethane linkages, or halogen substliuents, or combinations thereof; with the proviso that the dienes contain double bonds capable of undergoing reaction with SH groups of a poiythiol, and forming covalent G~S bonds. Often the compound (2) having at least two double bonds comprises a mixture of dienes that are different from one another.

[0081| The compound {2} having at least two double bonds may comprise acyclic non-conjugated dienes, acyclic polyvinyl ethers, allyl (meth)aeryiafes vinyl- (meth)acrylates, di(meth)acryiate esters of diols, di(mefh)acrylate esters of dithiols, di(meth)acrylate esters of poly{ai kylenegiycoi) diols, monocyclic non-aromatic dienes, polycyclic non-aromatic dienes, aromatic ring-containing dienes, diallyl esters of aromatic ring dicarboxylic acids, divinyl esters of aromatic ring dicarboxylic acids, and/or mixtures thereof.

[0082] Non-limiting examples of acyclic non-conjugated dienes can include those represented by the following general formula:

wherein R can represent Ci to C30 linear or branched divalent saturated aikyiene radical, or C₂ to C30 divalent organic radical including groups such as but not limited to those containing ether, thioether, ester, thioester, ketone, po!ysulfide, su!fon© and combinations thereof. The acyclic non-conjugated dienes can be selected from 1 ,5- hexadiene, 1 ,6-heptadiene, 1 ,7-octadiene and mixtures thereof.

f0083j Non-limiting examples of suitable acyclic polyvinyl ethers can Include those represented by the following structural formula;

CH₂=CH-0-f- R² -0-)_m -CH=CH₂ wherein R can be C₂ to C₆ n-aiky!ene, C₃ to C₆ branched aikyiene group, or - (CH₂ ·^■ ~)p ~~0~~]q ~-{-CH₂ ~-)r ~~, m can be a rational number from 0 to 10, often 2; p can be an integer from 2 to 6, q can be an integer from 1 to 5 and r can be an integer from 2 to 10.

[0084] Non-limiting examples of suitable polyvinyl ether monomers for use can include divinyl ether monomers, such as ethylene glycol divinyl ether, diethyiene glycol divinyl ether, triethyfeneg!ycol divinyl ether, and mixtures thereof.

[0085] Di(meth)acryiate esters of linear dlols can include ethanediol di( meih)acrylate, 1 ,3-propanedioi dimethacrylate, 1 ,.2-propanediol di(meth)acry!ate, 1 ,4-butanedio! di(meth)acryiate, 1 ,3-butanedio! di(meth)acry!aie, 1 ,2-butanediol di{meth)acrylate, and mixtures thereof.

[0086] Di{meth)acry!ate esters of dlthiols can include, for example, di(meth)aeryiate of 1 ,2-eihanedfthioi inducting oligomers thereof, di(meth)acrylate of

dimercaptodiethyi sulfide (i.e., 2,2' hioethanedithiol di(mefh)acrylate) Including oligomers thereof, di(meth)acr late of 3,6-dtoxa-1 ,8-octanedithiol including oiigomers thereof, di(meth)acryiate of 2-mercapioethyl ether including oiigomers thereof, di(meth)acry!ate of 4,4^>-ihiodibenzenethiol, and mixtures thereof,

[0087] Further non-limiting examples of suitable dienes can include monocyclic aliphatic dienes such as those represented by the following structural formula:

wherein X and Y each independently can represent CMO divalent saturated alkylene radical; or C t.₅ divalent saturated alkylene radical, containing at least one element selected from the group of sulfur, oxygen and silicon in addition to the carbon and hydrogen atoms; and Ri can represe ~Cio aik l; and

wherein X and Ri can be as defined above and R₂ can represent C2--C10 alkenyi. The monocyclic aliphatic dienes can include 1 ,4-cyclohexadsene, 4-vinyi-1~ cyciohexene, dlpentene and terpinene.

| 088| Non-limiting examples of polycyclic aliphatic dienes can include 5-vinyi-2- norbornene; 2,5-norbornadiene; dicycSopentadiene and mixtures thereof.

[0089] Non-limiting examples of aromatic ring-containing dienes can include those represented by the following structural formula;

wherein R₄ can represent hydrogen or methyl. Aromatic ring-containing dienes can include monomers such as diisopropenyl benzene, divinyi benzene and mixtures thereof.

[0090] Examples of dlallyi esters of aromatic ring dicarboxyiic acids can Include but are not limited to those represented by the following structural formula;

wherein m and n each independently can be an integer from 0 to 5. The diailyl esters of aromatic r ng dicarboxyiic acids can include odiallyf phtha!ate, m-diailyi phthaiate, p-diallyt phthalate and mixtures thereof.

[0091] Often, the compound (2) having at least two double bonds comprises 5~vinyi~ 2-norbornene, ethylene glycol divinyl ether, diethylene glycol divinyl ether, trieihylene glycol divinyl ether, butane dioi divinyl ether, vinylcyc!ohexene, 4-vinyl-1- cyclohexene, dspentene, terpinene, dicyciopentadiene, cyclododecadiene,

cyclooctadiene, 2-cyclopenten-l -yl-ether, 2,5-norbornadiene, diviny!benzene including 1 ,3-divinyibenzene, 1,2- divinyl benzene, and 1 ,4- divinylbenzene, diisopropenyibenzene including 1,3-diisopropeny!benzene, 1 ,2- diisopropenyibenzene, and 1,4- diisopropenyibenzene, ally! (meih)acrylate_> ethanedio! di(meth)acrylate, 1 ,3-propanediol di(meth)acryiate, 1 ,2-propanediol di(meih)acrylate, 1 ,3-butanediol di(meth)acrylate, 1 ,2-butanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(me†h)acryiate,

dimercaptodiethylsu!fide di(meth}acrylafe, 1 ,2-ethanedithio! di(meth)acryiate, and/or mixtures thereof.

[Ο092.| Other non-limiting examples of suitable di{mefh)acrylate monomers can Include ethylene glycol di(meth)acrylate, 1 ,3-butylene glycol di(meih)acrylate, 1,4- butanediol di(meth)acry!afe, 2,3-dimethyM ,3-propanedfol di{meth)acryiate, 1 ,6- hexanediol di(meth)acryiate, propylene glycol di{meth)acryiaie, dipropyiene glycol di{meth)acrylate, tripropyiene glycol di(meth)acryiate, tetrapropylene glycol

di(meth)acrylate, ethoxylated hexanediol di( meth)acrylate, propoxylated hexanediol di(meth)acry1ate, neopentyi glycol di(meth)acrylate, alkoxylated neopentyi glycol di(mefh)acrylate, hexylene glycol di(meth)acry1a†e, diethylene glycol

di{meth)acryiaie, polyethylene glycol di(meih)acryiate, thiodiethy!eneglycol

dl(meth)acrylaie, trimethylene glycol di(meth)acrylate, trietby!ene glycol

di(meth)acrylate, alkoxylated hexanediol dt(meih)acrylate, alkoxylated neopentyi glycol di(meth)acry!ate, pentanedlo.l di(mefh)acryjaie, cyclohexane dimethanol di(meth)acrylate, and ethoxylated bis-phenol A di(meth)acry!ate.

10093] The polythiois suitable for use in material (ii) in the preparation of the po!yurethane material in the first component, when reacted with a poiyisocyanate (i), can produce a polymerizate having a Martens hardness of at least 20 N/mm², or often at least 50, or more often between 70 and 200. Such poiymerizates are typically not elastomeric; L e., they are not substantially reversih!y deformable (e. g., stretchable) due to their rigidity and do not typically exhibit properties characteristic of rubber and other elastomeric polymers.

[0094] The active hydrogen component (b) further comprises at least: one amino alcohol, a compound containing both amine and hydroxy! functional groups. The amino alcohol has t e structure H₂N~l-GH, wherein L is a linear or branched alkyl, aryl, aralkyl, or alkaryl chain which may contain hetero atoms. In particular embodiments, the amino alcohol has the structure H₂N-CH₂-L^,-CH₂-OH₁ wherein L' is a linear or branched alkyl, aryl, aralkyl, or alkaryl chain which may contain hetero atoms. Such materials more often have the structure:

wherein R is H or a C to C4 alkyl group and n is an integer from 1 to 10.

|00 5] As noted above, the amino alcohol is often aliphatic. Aliphatic materials lend better flexibility to the final product, providing better impact resistance. Optical products prepared according to the method of the present invention, with aliphatic materials, also demonstrate better light stability and less yellowing, compared to those prepared with aromatic materials. Aromatic starting materials such as aromatic amines are also known to have relatively short shelf lives and are subject to oxidation and yellowing.

[Θ096] It is somewhat counterintuitive to use aliphatic materials because aliphatic polyamines react too quickly with isocyanates to control the formation of a po!yurea, often having very short gel times. However, the use of an aliphatic compound containing both amine and hydroxy! functional groups as in the present invention slows the reaction with the isocyanate compared to a reaction of an aliphatic polyamine with an isocyanate. At the same time, the use of an aliphatic compound containing both amine and hydroxy! functional groups provides for desirable physical properties in the final product such as thermal stability and hardness, allowing for post-production lens processing. It is believed that this is due to the urea linkages present in the polymerizate. Urea linkages also render the final product norv elasto eric.

[0097] The compound containing both amine and hydroxy! functional groups typically has a number average molecular weight of 60 to 450- Materials having higher molecular weights may contribute to opaqueness, Often the material containing both amine and hydroxy! functional groups comprises ethanoiamine, diethanolamine, amino-2-propanol, 2-amino~1 -methyi-1 propanol, 2-amino-1~butano! and/or 2~(2- am?noetnoxy)e.thanol (diethylene giycolamfne, or DGA), Typically the material containing both amine and hydroxy! functional groups is present in the active hydrogen component (b) in an amount of 5 to 70 percent by weight, often 10 to 70 percent by weight, more often 15 to 50 percent by weight, based on the total weight of resin solids in component (b). Typically the material containing both amine and hydroxy! functional groups is present in the reaction mixture in an amount of 5 to 25 percent by weight, based on the total weight of resin solids in the reaction mixture. |0098| As noted above, in certain embodiments of the present invention, the reaction mixture is essentially free of po!yamlnes. In particular, the active hydrogen component (b) Is often essentially free of 2,4~diamino^«3,5-dietnyi~toiuene, 2,6- diamino-3,5~diethyl~toiuene and mixtures thereof (collectively "diethyltoluenediamine" or "DEI DA^").

[0 99| The reaction mixture may further comprise a solvent, particularly when it is used to prepare an optical film. Suitable solvents may include any organic solvents known to those skilled In the art, provided they are not reactive with isocyanate functional groups. Examples are ketones, furans, aromatic solvents, and chlorinated solvents. Suitable solvents can include, but are not limited to: acetone, amy! propionate, aniso!e, benzene, butyl acetate, cyciohexane, dialkyl ethers of ethylene glycol, e.g., diethylene glycol dimethyl ether and their derivatives (sold as CELLOSOLVE^® industrial solvents), diethylene glycol dibenzoate, dimethyl sulfoxide, dimethyl formamide, dimethoxybenzene, ethyl acetate, methyl cyciohexanone, cyclopentanone, methyl ethyl ketone, methyl isobutyl ketone, methyl propionate, propylene carbonate, ietrahydrofuran, toluene, xylene, 2-methoxyeihyl ether, 3- propylene glycol methyl ether, methylene chloride, and mixtures thereof. The solvent may be present In the first component in an amount of 0 to 95 percent by weight, or 20 to 95 percent by weight, or 20 to SO percent by weight, or 40 to 60 percent by weight, based on the total weight of the first component. Typically the solvent is present In an amount such that the viscosity of the first component is reduced to a workable viscosity, such as to a viscosity of 10 to 100 cps, for example to 15 to 20 cps,

[ΘΘ1ΘΘ] In step (2) of the method of the present invention, the isocyana.te functional groups are allowed to react with the amine functional groups in the reaction mixture at a temperature and for a time sufficient to form an intermediate product. The intermediate product comprises a po!yurea functional prepolymer having hydroxy! functional groups. The intermediate product is in admixture with the polyol and/or pofyihiol and, optionally, excess amino alcohol from the active hydrogen component (b).

[00101} After preparation of the Intermediate product described above, it is mixed In step (3) with additional po!yisocyanaies and optionally a catalyst to form a second reaction mixture. Such mixing may be performed in a urethane mixing machine, The polyisocy nates may be any of those disclosed above, and may be the same as or different from those used in the polyisocya nate component (a). Suitable catalysts can be selected from those known in the art. Non-limiting examples of suitable catalysts can be chosen from the group of Lewis bases, Lewis acids and insertion catalysts as described in Uilmann's Encyclopedia of Industrial Chemistry, 5th Edition, 1992, Volume A21 , pp. 673 to 874, The catalyst can be a stannous salt of an organic acid, such as but not limited to stannous octoate, dibuty! tin diiaurate, dibufyl tin diacetafe, dibutyi tin mercaptide, dibutyl tin dimaleate, dimethyl tin diacetafe, dibuty!tin dichloride, 1 ,4~diazabicyclo|2.2.2]ocfane, and mixtures thereof. The catalyst can alternately be zinc octoate, bismuth, or ferric acetylacetonate.

{00102} Further non-limiting examples of suitable catalysts can include tin compounds such as dibutyl tin oxide, phosphines, tertiary ammonium salts and tertiary amines such as but not limited to irieihy!amine, triisopropyiamine, dimethyl cydohexyfamine, N.N-dimethyibenzylamine and mixtures thereof. Such suitable tertiary amines are disclosed in United States Patent 5,693,738 at column 10, lines 6-38, the disclosure of which is incorporated herein by reference.

[00103] When employed, the catalyst level can vary and can be dependent upon a variety of factors such as the type and amounts of the reactive compounds used, as well as reaction conditions, speed of reaction, and degree of reaction desired. Typically, an organofin catalyst is present in component B In an amount less than 300 ppm, often less than 250 ppm, and a tertiary amine catalyst is present in an amount less than 1000 ppm, usually less than 800 ppm, often about 720 ppm, based on the total weight of the second reaction mixture,

100104] The second reaction mixture may be immediately formed info a film such as by dispensing onto a support substrate such as in a conventional solvent casting process. Suitable film-forming techniques include; formation of films by casting the film onto a casting roil after extrusion through a fiat film-forming die, formation of films by the "blown film" technique wherein a film-forming composition is forced through a circular die and the exiting circular film profile is expanded by compressed air, casting a film-forming composition into a billet or other solid form and subsequently skiving the film from the formed billet, as well as other techniques known in the art. Of these techniques, commonly used methods for the production of film include film casting techniques and the production of film by blown film techniques,

[00105] It should further be mentioned that other commonly used additives can be included in the first and/or second reaction mixtures. Such additives can include but are not limited to light stabilizers, heat stabilizers, antioxidants, ultraviolet light absorbers, mold release agents such as ZELEC^® UN available from Stepan Company, static (non-photochromic) dyes, pigments and flexibillzing additives.

[00106] Support substrates onto which the reaction mixture is cast have smooth surfaces and may comprise, for example, glass, stainless steel, and the like, as well as polymeric substrates for example, polyethyleneterephthaiafe, polyimide, or silicone, provided the material from which the substrate is made can withstand the subsequent curing temperatures. 10.0107] The reaction mixture is dispensed onto the support substrate to form a substantially uniform thickness to yield a dry film thickness of 0.5 to 20 mils (12.7 to 508 microns), or 1 to 10 mils (25.4 to 254 microns), or 2 to 4 mils (50,8 to 101 .6 microns) after cure.

[00108] After application of the reaction mixture to the substrate, an at least partial film is formed on the surface of the substrate by driving solvents out of the film by mild heating or by an air-drying period, typically involving exposure to ambient conditions for about 1 to 20 minutes. The film on the substrate is then heated to a temperature and for a time sufficient to yield a cured film, In the curing operation, solvents are driven off and the reactive functional groups in the reaction mixture are reacted together. In the making of a pofyurethane-urea film, for example, the heating or curing operation may be carried out at a temperature in the range of from 100° to 210°C for a period of 10 to 100 minutes, At this temperature range, reaction mixtures containing polyurethane materials as a first component having number average molecular weights of up to 1500 can cure within 40 to 70 minutes. In alternate embodiments, curing may be carried out at a lower temperature range of ambient (for example 25°C) to 100°C for a longer time period of from 100 minutes to five days. Cure temperatures and dwell times will be dependent on the nature of the reactants, including type of reactive groups, the presence of any catalysts, etc.

[00109] The cured, non~elastomenc polyurethane-confaining film prepared according to the method of the present invention may be used, for example, as one or more of the protective and/or support film layers in a polarizing optical element for use in a multi-layer optical article such as a liquid crystal display (LCD).

[OOllfi] Alternatively, the second reaction mixture may be introduced into a mold of any desired shape at a temperature and for a time to form a thermosef polymerizate. The second reaction mixture typically undergoes an exothermic reaction, and after mixing it is introduced, usually by injection, into a mold. The temperature of the reaction mixture as it is introduced info the mold is usually up to 130°C, often up to 120°C. The reaction mixture Is held in the mold at a temperature and for a time sufficient to essentially cure the reaction mixture and form a molded optical article. The mold may have any shape desired for the final product, it Is typically a lens moid; often a mold for an ophthalmic tens. The molded article may then be released from the moid.

[00111| In an embodiment of the present invention wherein the optical article is a lens, the second reaction mixture, which can be optionally degassed, can be introduced, usually by injection, into a mold and the mold can be heated (i.e., using a thermal cure cycle} using a variety of conventional techniques known in the art. The thermal cure cycle can vary depending on the reactivity and molar ratio of the reactants, and the presence of catalyst(s). In particular embodiments, thermal cure cycle can include heating the mixture from room temperature to a temperature of 200°C over a period of from 0.5 hours to 120 hours; or from 80 to 15G°C for a period of from 5 hours to 72 hou s.

[00112] Optical articles prepared by the process of the present invention demonstrate high yield, high transparency (light transmittance of at least 80%), very low haze, tow flow lines and low inclusions, fvloreover, the optical articles prepared by the method of the present Invention demonstrate a refractive index of at least 1 ,52, such as at feast 1.53.

[00113] The present invention further provides a method of preparing a transparent, non-elastomeric optical article using a "one-batch" or "one-pot" technique. This method comprises the following steps:

(1 ) combining to form a reaction mixture:

(a) a polyisocyanate component comprising one or more different, polyisocyanates; and

(b) an active hydrogen component comprising:

(bl ) a first component that is essentially free of amino groups comprising at least, one polyol; and

(b2) a second component comprising at least one polyol and/or polythiol and at least one compound containing both amine and hydroxyi functional groups and has the structure H₂N-L-OH, wherein L is a linear or branched alkyi, aryi, aratkyi, or alkaryl chain which may contain hetero atoms, wherein the at least one polyol has a number average molecular weight of 60 to 450;

(2) introducing the reaction mixture to a mold of a desired shape at a temperature and for a time sufficient to form a thermoset polymerizate; and (3) releasing the polymenzate from the mold to yield a transparent optical article.

001141 The poiyisocyanate may be any of those disclosed above. The polyisocyanate component typically comprises isophorone diisocyanate, dicydphexyi methane diisocyanate, hexamethyiene diisocyanate, diphenylmethane- 4,4 -diisocyanate, eta-tetramethylxylene diisocyanate (1 ,3-bis(1 -isocyanato-1- methylethyi )-benzene), and/or meta-xylylene diisocyanate.

[00115] In particular embodiments of the present invention, the reaction mixture, in particular the active hydrogen component (b) is essentially free of polyamines and essentially free of compounds containing both amino and aromatic functionality wherein the amino groups are attached directly to the aromatic ring,

[0_.0116] in the active hydrogen component (b), the polyol in the first component (bl ) may be any of those disclosed above, provided that less than 40 percent by weight, often less than 35 percent by weight, more often less than 30 percent by weight of the polyols in the first component (b1 ) has a number average molecular weight greater than 500.

[00117] The second component (b2) comprises at least one poiyol and/or po!ythtoi, which may be any of those described above. The second component (b2) further comprises an amino alcohol as described above, which often has a number average molecular weight of 60 to 450. The amino alcohol usually comprises ethanolamine or DGA.

100118] The active hydrogen component (b) may further comprise a thiol functional compound as described above,

[00119] In step (2) of this method of the present invention, the reaction mixture may be immediately formed into a film such as by dispensing onto a support substrate using casting processes as described above, Alternatively, the reaction mixture may be mixed such as in a urethane mixing machine and introduced into a moid of any desired shape at a temperature and for a time to form a thermoset poiymerizate, such as by the reaction injection molding steps described above,

[00120] The molded article may then be released from the mold or support substrate in step (3), Optical articles prepared by the process of the present invention demonstrate high yield, high transparency, very low haze, low flow lines, low inclusions, and a refractive index of at least 1 ,52.

[00121] In an additional embodiment of the present invention, a method of preparing a cured, non-e!astomeric polyurethane-containing optical article is provided. The method comprises:

(1 ) combining to form a reaction mixture that is essentially free of yrefhanation catalysts:

(a) a polyisocyanate component comprising one or more different polyisocyanat.es; and

(b) an active hydrogen component comprising at least one polyol and/or polythioi and at least one aliphatic compound containing both amine and hydroxy! functional groups wherein the compound containing both amine and hydroxy! functional groups is present in stoichiometric excess with respect to amine groups and has the structure H2N-L-OH, wherein L is a linear or branched alky!, ary!, aralkyl, or alkaryi chain which may contain hetero atoms;

(2) allowing the polyisocyanate component fo react with at least a portion of the amine functional groups in the active hydrogen component at a temperature and for a time sufficient to consume essentially all of the isocyanate functional groups and form an intermediate product comprising a po!yurea prepofymer having hydroxy! functional groups in admixture with the polyol and/or polythioi and the compound containing both amine and hydroxy! functional groups;

(3) mixing the intermediate product formed in step (2) with additional polylsocyanates and optionally a urethanation catalyst to form a second reaction mixture,'

(4) introducing the second reaction mixture formed in step (3) to a mold of a desired shape at a temperature and for a time sufficient to form a thermoset polymerizate; and

(5) releasing the polymerizate from the moid to yield a transparent optical article.

[00122J In step (2) of this method, the isocyanate groups in the polyisocyanate component are allowed to react with the amine functional groups until 1 to 99 percent, such as 10 to 90 percent, or such as at least 20 and up to 90 percent of the amine equivalents are consumed, or at least 20 up to 80 percent, or at bast 20 up to 70 percent. In step (2) of the method, the reaction continues for a time sufficient to consume essentially ail of the isocyanate functional groups. An intermediate product is formed in step (2) comprising a poiyurea prepolymer having hydroxyl functional groups in admixture with the po!yol and/or po!y hiol and the compound containing both amine and hydroxy] functional groups.

100123] In an additional embodiment of the present invention, a method of preparing a cured, non-eiastorneric polyurethane-coniaining optical article Is provided. The method comprises:

(1 ) combining to form a reaction mixture:

(a) a polyisocyanate component comprising one or more different po!yisocyanates; and

(b) at least one polyol, wherein the polyisocyanate component is present in stoichiometric excess relative to hydroxyl functional groups;

(2) allowing the components to react at a temperature and for a time sufficient to consume essentially ail of the hydroxy! functional groups and form an intermediate product comprising a poiyurethane prepolymer having isocyanate functional groups in admixture with excess polyisocyanate;

(3) mixing the intermediate product formed in step (2) with optionally an active hydrogen component comprising at least one polyol and/or polythiol, and at least one compound containing both amine and hydroxyl functional groups wherein the compound containing both amine and hydroxyl functional groups has the structure H₂N-L-OH, wherein L is a linear or branched aikyl, aryl, aralkyl, or alkaryi chain which may contain hetero atoms, to form a second reaction mixture;

(4) Introducing the second reaction mixture formed in step (3) via injection to a mold of a desired shape at a temperature and for a time sufficient to form a thermoset poiymenzate; and

(5) releasing the poiymerizate from the mold to yield a transparent optical article.

[0Θ124Ι The various components and process steps may comprise any of those described above. EXAMPLES

1001251 The following examples describe the formation of optical articles according to the present invention. The optica! articles are characterized by physical properties, in the foregoing examples, Fisher microhardness ("FMH") values were determined in accordance with ISO 1457? using a H100C Microhardness Measurement System available from Fischer Technologies. ABBE (e) values and Refractive Indices (Rl (e)} were determined using a Metricon Model 2010 Prism Coupler, Thin Film Thickness / Refractive Index Measurement System available from Metricon Corporation. Glass Transition Temperatures (Tg) were measured by either differential scanning calorimetry or dynamic mechanical analysis as indicated for each example.

f 001.26] The materials used in the Examples below are abbreviated as follows:

Isocyante Name

11 isophorone dlisocyanate

12 4,4"-methyienebis(cyciphexy! isocyanate)

13 VESTANAT® 1890 (a polyfunctions! aliphatic isocyanate from Evonik

industries)

14 DESMODUR® N3300A (a poiyfunctional aliphatic isocyanate from Bayer

Materia!Science)

15 DESMODUR® N3400 (a poiyfunctional aliphatic isocyanate from Bayer

MatertalSclence)

16 DESMODUR® N3600 (a poiyfunctional aliphatic isocyanate from Bayer

Materia!Science)

Amino Alcohol

A1 Ethanolamine

A2 Diethano!amine

A3 Diethyleneglycolamine

A4 amino-2-propano!

A5 2-amino-1"inethy!-1-propanol

A6 2-amino~1~butanol

Poiyol

P1 6-mole efhoxyiatecl Bisphenol A

P2 15-moie ethoxyiated Bisphenol A

P3 30-mole ethoxyiated Bisphenol A

P4 Ethanedioi

P5 Propanediol

P6 Butanedipl

P7 Pentanedioi

P8 diethyiene glycol

P9 Decanediol

P10 polyethylene glycol 200 g/moie P1 1 polyethylene glycol 400 g/mole

P12 polyethylene glycol 600 g/mole

P13 DiEXTER® G 1 100-225 (an aliphatic polyester dio! from COi USA, Inc.)

P14 CAPA® 2047A (an aliphatic polyester dioi from Perstorp)

PI 5 STEPANOL® PD-200LV (aromatic polyester dioi from Stepan Company)

PI 6 Trimeihyiolpropane

P17 trimeihyiolpropane ethoxylate, 170 g/mola

P18 t lmethylo!propane ethoxylate, 450 g/mole

P19 trimethylo!propane ethoxylate, 1014 g/mole

P20 15-mole ethoxyiated peniaeryihritol

P21 trimet yioipropane propoxylate, 308 g/mole

P22 10~mole ethoxyiated Bisphenol A

P23 tetrabromo Bisphenol A ethoxylate, 631 g/mole

P24 SYN FAC® 8385 (afkoxyiated Bisphenol A from MRIiken Chemical)

P25 polyethylene glycol, 1000 g/mole

P26 polypropylene glycol, 425 g/mole

P27 DIEXTER© G 1100-112 (aliphatic polyester dioi from COIM USA, Inc.)

P28 DIEXTER® G 5500-225 (aliphatic polyester dioi from COIM USA, Inc.)

P29 CAPA® 2077A (aliphatic polyester dioi from Perstorp)

P30 Bisphenol A

P31 Thiodiglycol

P32 Cyciohexanedimetbanol

Qthex_.mon jmers

01 Methyienedianiiine

02 JEFFA I E© D230 (amine terminated po!yether from Huntsman

Corporation)

03 JEFFAMINE® HK511 (amine terminated po!yether from Huntsman

Corporation)

04 JEFFAMINE® XTJ235 (amine terminated Bisphenol A alkoxylate from

Huntsman Corporation)

05 2,2'-thiodiethanethio!

[00127] Examples 1-37 illustrate the preparation of optical articles wherein all the materials were mixed together and cast. The constituents of Component A were mixed together, when applicable, in the ratio described in Table 1 , This mixture was degassed at room temperature under vacuum for four hours. In a separate vessel, the constituents of Component 8 were combined and mixed in the ratio described in Table 1 , then degassed under vacuum at room temperature for four hours. To cast the compositions, Component A and Component B were then mixed together under vacuum while heating to approximately 80°C according to the ratios set forth in Table 2. Upon reaching a homogeneous appearance, the resulting mixture was charged to a glass mold of dimensions 15 cm x 15 cm x 0.3 cm which was preheated to 130°C. The material was cured in an oven at 130°C for 18 hours. The resulting materials were dear and colorless, exhibiting the properties listed in Table 2.

Table 1,

Examp [ Com ponent A Component B

fe ^"Constitue Ratio (by Constituents Ratio (by weight)

1 11:12 0.330 : 0,870 A1:P1:P19 0.222 : 0.262 : 0.517

2 11:12 0.291 : 0.709 A1:P1;P17;02 0,269 0.516 : 0.081 : 0.134

3 1:12 I 0.290 : 0.710 1 A1;P1:P17:03 0.270 : 0.514 : 0.081 : 0.135

4 11:12- 0.311 : 0.689 1 A1:P1:P15:P1 0.240 : 0,329 : 0.240 : 0.190

5 11:12 : 0.284 .0.716 A1:P1:P10:P2 0.276 : 0.348 : 0,180 :.0.196

8 M:I2 0.325 0.675 A1:P1;P10;P1 0.364 : 0.424 : 0.121 : 0.091

7 M:I2 0.236 0.764 A1:P1:P5 0.348 : 0.328 : 0.326

8 11:12 0.210 0.790 A1:P1:P6:P17 0.261 : 0.353 : 0.252 : 0.134

9 12 A1:P1:P11:P1 0.347 : 0.405 ; 0,162 : 0.087

10 M:i2 ^■ 0.315 0.685 A1:P1:P17:P2 0.236 : 0.297 : 0.071 : 0.396

11 11:12 0.310 0.690 A1:P1:P17:P2 0.242 : 0,305 : 0.073 : 0.380

12 11:12 0.299 0.701 A1:P1:P17:P2 0.253 : 0.318 : 0.076 : 0,354

1 11:12 0.295 0.705 A4:P1:P14:P1 0.303 : 0.318 : 0,303 :

14 11:12 0.295 0.705 A1:P1:P17:P2 0,258 : 0.325 : 0.077 : 0.340

15 12:13 0.088 0.912 A1:P1:P10:P1 0.311 : 0.391 : 0.205 : 0.093

16 12:14 0.800. 0.200 A1:P1;P10 0.307 : 0.387 : 0.307

17 12:16 0.800 0.200 A1:P1:P10 0.305:0.384:0.311

18 12:15 0.800 : 0.200 A1:P1:P10 0.307 : 0.387 : 0.307

19 12 A1;P1:P18:04 0.178 : 0.421 : 0.178 ; 0,223

20 12 A3:P1 0.595 : 0.405

21 12 A3:P1:P25 0.482 : 0.265 : 0.253

22 12 - A3:P1:P10:P1 0.475: 0.317: 0.096: 0.061:

23 12 A3:P1:P16 0.538 : 0.419 : 0.043

24 j - A3:P1:P17 0.463 : 0.463 : 0.075

25 12 A3:P1:05 0.521 ; 0.190 : 0.289

26 12 A3:P1:P17:P2 0.539 : 0.323 : 0.054 : 0.084

27 12 A3:P1:P 7 0.615 :0,358: 0.028 \

28 12 - A3:P11:P17:P 0.457 : 0.145 : 0.074 : 0.325 |

29 12 A3:P16:P24 0,461 : 0.078 : 0.461

30 12 » A3:P17:P22 0.524 : 0.025 : 0.450

31 !2 - A3:P1:P9:P17 0.410 : 0.317 : 0.225 : 0.048

32 12 - I A3:A4:P1:P17 0.176 : 0,248 ; 0,496 : 0.080

33 12 A3:A5:P1:P17 0.207 : 0.239 : 0.477 : 0.077

34 12 - A3:A6.P1:P17 0.121 : 0.322 : 0.483 : 0.078 b 12 A3:P1:P17:P3 0.534: 0.237 : 0.085: 0.144 |

36 12 ! A3:P1:P17:01 0.361 : 0.378 : 0.72 : 0.189

37 1 12 j A3:P1:P17:P3 0,154 : 0.308 : 0.075; 0,463 Tsfol® 2,

[00128] Examples 38-88 illustrate the preparation of opticai articies comprising urea- containing diois which are formed prior to casting by the reaction of amino alcohol and polyols with an isocyanate.

[00129] Prior to casting, a urea-containing polyo! mixture was synthesized as Component B. For each Component B the following procedure was followed: To a reactor equipped with an agitator and thermometer was charged the amino alcohol and polyoi constituents of Component 8 according to the amounts described in Table 3. The amino alcohol and polyoi mixture was stirred to yield a homogeneous solution. The isophorone diisocyanate (11 ) constituent of Component B was added dropwise to the solution with stirring, at a rate sufficient to maintain the reaction temperature below 60° C. After the addition, the reaction temperature was maintained between 55-80X and stirring was continued until no isocyanate was detected by !R, yielding a clear viscous liquid.

[00130] The materials of Examples 38-68 were cast to form optical articles by the following procedure: A quantity of Component B (urea-containing polyoi) was stirred at between 60-80°C under reduced pressure for 4 hours. In a separate vessel, Component A (4,4'-methylenebis(cyclohexyl isocyanate), "12") was held under reduced pressure until degassed. Component A was then added to Component B in the cast ratio indicated In Table 4 and the resulting mixture was stirred continuously under reduced pressure. Upon reaching clarity, the mixture was poured Into a two- part glass mold with a cavity thickness of 0.125 inches. The moid was placed info a preheated oven and subjected to a cure cycle according to Table 4. Upon demolding, a clea hard polymer was obtained, demonstrating the properties listed in Table 4.

Table 3_*

Component 1 Component B

Example A

38 12 !1;A1;P1:P10 I 177:96:136: 36

39 \/.. M:A1:P1:P6 159:88:163:81

40 12 I1:A1:P1:P6:P17 145:78:108:74:40

41 12 11:A1:P1:P5 173:94:89:89

42 2 I1:A1:P1:P5 153:83:156:78

43 12 I1:A1: P1:P5:P13 153:82:78:78:78

44 1 12 I1-A1. P5:P13 153:82:78:156

45 12 I1:A1:P4:P15 124:67:84:224

46 12 I1:A1:P1:P3:P4 149:81:37:117:77

47 12 H:A1:P1:P5 173:94:89:89

48 !2 i1:A1:P1:P16 104:57:314:60

49 12 !1:A1:P1:P3:P10 157:86:173:110:81

50 12 Π:Α1:Ρ3:Ρ10:Ρ20 157:88:164:81:118

51 12 M:A1:P1:P3:P10 140:76:202:129:72

52 12 i1:A1:P1:P3:P10 123:67:231:148:63

53 12 i1;A1:P1;P3:P4 130:71:56:179:87

54 12 i1:A1:P2:P10 207:112:154:106

55 12 S1:A1:P1:P19 124:67:356:89

56 12 Π:Α1:Ρ1:Ρ19 162:87:300:75

57 12 !1:A1:P1:P17:P18 167:91:230:26:60

58 12 H:A1:P2:P17:P18 159:87:287:25:57

59 12 Π:Α1:Ρ1:Ρ17:Ρ1δ 133:72:313:21:48

60 12 Π:Α1:Ρ1:Ρ17 125:68:294:64

61 12 !1:A1:P1:P17 150:81:308:38

62 12 i1:A1:P1:P17 154:84:336:20 |

63 12 !1:Α1;Ρ1·Ρ10 168:91:230:86 !

64 12 I1:A1:P1:P2;P17 159:87:41:286:41 |

65 12 I1:A1:P2:P17:P18 155:84:279:46:34

66 12 i1;A1:P3:P17:P18 1.57:86:284:34:47

67 12 I1:A1:P1:P8:P16 114:62:284:57:15

68 12 I1:A1:P1:P13:P16 173:94:221:89:16

" Tg measured by DMA using a Perkin Eimer Pyris Diamond Dynamic Mechan cai Analyzer.

Tg measured by DSC using a TA instruments Q200 Differential Scanning

Calorimeter,

|00131] Whereas particular embodiments of this invention have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the detaiis of the present invention may be made vvithout departing from the invention as defined in the appended claims.

Claims

What is claimed is:

1 . A composition for the preparation of a transparent, non-eiastomeric optical article, the composition comprising:

(1 ) a poiyisocyanafe component comprising one or more different poSyisocyanat.es; and

(2) a component that is reactive with isocyanates, comprising:

(a) optionally at least one poiyol having a number average molecular weight greater than 500;

(b) (i) at least one poiyol and/or po!ythiol and (si) at least one compound containing both amine and hydroxy! functional groups, wherein the compound (ii) has a number average molecular weight less than 500; and optionally

(3) a urethanation catalyst.

2. An optical article prepared from the composition of claim 1 .

3. A composition for the preparation of a transparent, non-eiastomeric optical article, the composition comprising:

(1 ) a polyisocyanate component comprising one or more different polyssocyanates; and

(2) a component that is reactive with isocyanates, comprising:

(b) (!) at least one poiyol and/or poiythiof and, optionally (ii) at least one compound containing both amine and hydroxyl functional groups, wherein the compound (ii) has a number average molecular weight less than 500; and

(c) a urea-containing diol reaction product of a reaction mixture substantially free of urethanation catalyst, the reaction mixture comprising a iisocyarsate and at least one aliphatic compound containing both amine and hydroxyl functional groups, wherein the equivalent ratio of amine functional groups to isocyanate functional groups is at least 1 ; and optionally

{3} a urethanation catalyst. 4, An optical article prepared from the composition of claim 3.

5. A method of preparing a transparent, non-elastomeric optical article comprising:

(1 ) combining to form a reaction mixture that is essentially free of urethanation catalysts:

(a) a poiyisocyanate component comprising one or more different po!yisocyanaies; and

(b) an active hydrogen component comprising at least one polyol and/or polythioi and at least one compound containing both amine and hydroxyi functional groups wherein the compound containing both amine and hydroxy! functional groups has the structure f-feN-L-OH, wherein L is a linear or branched aiky!, aryl, araikyi, or alkary! chain which may contain hefero atoms;

(2) allowing the poiyisocyanate component to react with amine functional groups in the active hydrogen component at a temperature and for a time sufficient to form an intermediate product comprising a polyurea prepolymer having hydroxyi functional groups in admixture with the polyol and/or polythioi and, optionally, the compound containing both amine and hydroxyi functionaf groups;

(3) mixing the intermediate product formed in step (2) with additional polyisocyanates and optionally a urethanation catalyst to form a second reaction mixture;

(4) introducing the second reaction mixture formed In step (3) to a mold of a desired shape at a temperature and for a time sufficient to form a thermoset poiymerizate; and

(5) releasing the poiymerizate from the moid to yield a transparent optical article.

8. The method of claim 5 wherein the poiyisocyanate component:

comprises isophorone diisocyanate, dicyc!ohexy!methane diisocyanate,

hexamethylene diisocyanate, diphenylmethane-^'-diisocyanate, rneta- tetramethylxylene diisocyanate {1 ,3~bis(1 -isocyanato-1~methylethyl)~~ benzene), and/or meta-xylylene diisocyanate.

7. The method of claim 5 wherein the equivalent ratio of amine functional groups to isocyanate functional groups in the reaction mixture formed in step (1) is at least 1 ,

8. The method of claim 5 wherein the compound containing both amine and hydroxy! functional groups has a number average molecular weight of 80 to 450.

9. The method of claim 5 wherein the compound containing both amine and hydroxy! functional groups has the structure:

wherein R is H or a Ci to C₄ a!kyi group and n is an integer from 1 to 10.

10. The method of claim 5 wherein the compound containing both amine and hydroxy! functional groups comprises ethanoiamine, diethanolamine, amino-2- propanol, 2-amino-1-methyl-1 -propanoi, 2-amino-1-buianol and/or drethylene ^■glycolamine.

11. The method of claim 10 wherein the compound containing both amine and hydroxy! functional groups is present in the active hydrogen component (b) in an amount of 5 to 70 percent by weight, based on the total weight of resin solids in component (b).

12. The method of claim 5 wherein the catalyst added in step (3) comprises phosphines, stannous octoate, dibutyl tin dilaurate, dibutyl tin diacetate, dibutyl tin mercapisde, dibutyl tin dimaieate, dimethyl tin diacetate, dimethyl ti oxide, dibutyltin dichloride, 1 ,4-diazabicyclo[2.2.2]octane, zinc octoate, bismuth, ferric aeetylacetonate triethylamine, triisopropyiamine, dimethyl cyciohexyiamine, N,N- dimethylbenzyiamine or mixtures thereof.

13. The method of claim 5 wherein the active hydrogen component (b) comprises (I) at least two different polyols and/or poiythiols and (ii) at least one compound containing both amine and hydroxy! functional groups, wherein the amine and hydroxy functional groups on the compound (ii) are not directiy bonded to aromatic rings,

14. The method of claim 13 wherein at least one of the polyols is an aromatic ring-containing polyoi wherein hydroxy! groups in the polyol are not directly bonded to aromatic ring.

15. The method of claim 5 wherein the transparent optical article demonstrates a refractive index of at least 1.52.

18. The method of claim 5 wherein the reaction mixture is essentially free of compounds containing both amino and aromatic functional groups,

17. A method of preparing a transparent, non~elastomeric optical article comprising;

(1 ) combining to form a reaction mixture:

(a) a polyisocyanate component comprising one or more different polyisocyanates; and

(b) an active hydrogen component comprising;

(hi ) a first component that is essentially free of amino groups comprising at least one polyoi; and

(b2) a second component comprising at least one polyol and/or po!ythlol and at least one compound containing both amine and hydroxy! functional groups and has the structure H₂N-L-OH, wherein L. is a linear or branched alkyl, aryi, aralkyi, or alkaryl chain which may contain hetero atoms, wherein the at least one polyol has a number average molecular weight of 80 to 450;

(2) introducing the reaction mixture to a mold of a desired shape at a temperature and for a time sufficient to form a thermoset poiymerizafe; and

18. The method of claim 17, wherein less than 40 percent by weight of the polyois in the first component (bl } have a number average molecular weight greater than 450.

19. The method of claim 18, wherein less than 35 percent by weight of the polyois in the first component (bl ) have a number average molecular weight greater than 450.

20. The method of claim 19, wherein less than 30 percent by weight of the polyois in the first component (b1 ) have a number average molecular weight greater than 450.

21 . The method of claim 17 wherein the polyisocyanate component comprises isophorone diisocyanate, dicyc!ohexy! methane diisocyanate, hexamethylene diisocyanate, diphenyimethane^^'-diisocyanaie, meta- tetramethy!xylene diisocyanate ( ,3-bis(1 -isocyanato-1 -methylethylVbenzene), and/or meta-xylylene diisocyanate,

22. The method of claim 17 wherein the compound containing both amine and hydroxy! functional groups has a number average molecular weight of 60 to 450.

23. The method of claim 17 wherein the compound containing both amine and hydroxy! functional groups has the structure:

wherein R Is H or a C_f to C4 aikyi group and n is an integer from 1 to 0.

24. The method of claim 17 wherein the compound containing both amine and hydroxy! functional groups comprises ethanolamine, diethano!amine, amino-2- propane*!, 2-amino~1 ~rnethyi-1-pFQpanoi, 2-amino-1-butano! and/or diethyiene g!ycoSamine.

25. The method of claim 17 wherein the reaction mixture s essentially free of polyamsnes.

26. The method of claim 17 wherein the reaction mixture is essentially free of compounds containing both amino and aromatic functional groups.

27. The method of claim 17 wherein the reaction mixture is essentially free of polyols containing aromatic groups.

28. The method of claim 17 wherein the active hydrogen component (b) further comprises at least one pol thioL

29. The method of claim 17 wherein the transparent optical article demonstrates a refractive index of at least 1 .52.

30. A method of preparing a transparent, non-elasfomeric optical article comprising:

(a) a poiyisocyanate component comprising one or more different pol isoc nates; and

(b) an active hydrogen component comprising at least one poiyoi and/or po!ythiol and at least one compound containing both amine and hydroxy! functional groups wherein the compound containing both amine and hydroxy! functional groups is present in stoichiometric excess with respect to amine groups relative to isocyanate functional groups and has the structure HaN-L-OH, wherein L is a linear or branched alkyi, ary!, araikyi, or aikary! chain which may contain hefero atoms;

(2) allowing the poiyisocyanate component to react with at least a portion of the amine functional groups in the active hydrogen component at a temperature and for a time sufficient to consume essentially all of the isocyanate functional groups and form an intermediate product comprising a po!yurea prepo!ymer having hydroxy! functional groups In admixture with the po!yol and/or poiythiol and the compound containing both amine and hydroxy! functional groups;

(3) mixing the intermediate product formed in step (2) with additional polyisocyanates and a urethanation catalyst to form a second reaction mixture;

(4) introducing the second reaction mixture formed in step (3) to a moid of a desired shape at a temperature and for a time sufficient to form a thermosef poiymerizate; and

(5) releasing the po!ymerizate from the mold to yield a transparent optical article,

31. A method of preparing a transparent, non-elastomeric optical article comprising:

(1 ) combining to form a reaction mixture:

(a) a poiyisocyanate component comprising one or more different polyisocyanates; and

(b) at least one polyoi, wherein the poiyisocyanate component is present in stoichiometric excess relative to hydroxy! functional groups;

(2) allowing the components to react at a temperature and for a time sufficient to consume essentially ail of the hydroxy! functional groups and form a intermediate product comprising a poiyurethane prepolymer having isocyanate functional groups in admixture with excess po!yisocyanate;

(3) mixing the intermediate product formed in step (2) with optionally an active hydrogen component comprising at least one polyoi and/or poiythiol, and at least one compound containing both amine and hydroxy! functional groups wherein the compound containing both amine and hydroxy] functional groups has the structure H2 -L-OH wherein L is a linear or branched alkyl, aryl, aralkyl, or alkaryl chain which may contain hetero atoms, to form a second reaction mixture;

(4) introducing the second reaction mixture formed in step (3) via injection to a moid of a desired shape at a temperature and for a time sufficient to form a thermosef po!ymerizate; and (5) releasing the poiymerizaie from the mold to yield a transparent optical article.