WO2013174791A1

WO2013174791A1 - Phosphinyliminophosphoranes as flame retardants

Info

Publication number: WO2013174791A1
Application number: PCT/EP2013/060369
Authority: WO
Inventors: Rainer Xalter; Heinz Herbst; Christoph Fleckenstein; Klaus Stoll
Original assignee: Basf Se; Basf Schweiz Ag
Priority date: 2012-05-22
Filing date: 2013-05-21
Publication date: 2013-11-28

Abstract

The invention relates to flame retardant polymer compositions with (thio)phosphinyl- iminophosphorane compounds as active component. These compositions are especially useful for the manufacture of flame retardant compositions based on thermoplastic polymers, especially polyolefin homo- and copolymers, polycondensates, such as polyamines or polyesters, and particularly duroplastic polymers, such as polyepoxides.

Description

Phosphinyliminophosphoranes as flame retardants Description The present invention relates to the use of (thio)phosphinyliminophosphorane compounds in flame retardant polymer compositions. These compositions are especially useful for the manufacture of flame retardant compositions based on thermoplastic polymers, especially polyolefin homo- and copolymers, polycondensates, such as pol- yamines or polyesters, and particularly duroplastic polymers, such as polyepoxides. Flame retardants are added to polymeric materials (synthetic or natural) to enhance the flame retardant properties of the polymers. Depending on their composition, flame retardants may act in the solid, liquid or gas phase either chemically, e.g. as a spumes- cent by liberation of nitrogen, and/or physically, e.g. by producing a foam coverage. Flame retardants interfere during a particular stage of the combustion process, e.g. during heating, decomposition, ignition or flame spread.

There is still a need for flame retardant compositions with improved properties that can be used in different polymer substrates. Increased standards with regard to safety and environmental requirements result in stricter regulations. Particularly known halogen containing flame retardants no longer match all necessary requirements. Therefore, halogen free flame retardants are preferred, particularly in view of their better performance in terms of smoke density associated with fire. Improved thermal stability and less corrosive behaviour are further benefits of halogen free flame retardant compositions.

9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) has been known as flame retardant, but its use is limited to multifunctional epoxy resin compositions such as epoxy novolac resins. It is reactive with epoxy resins as it is monofunctional and acts as a chain terminator. For that reason, derivatives of DOPO have been developed which are bifunctional and can act as chain extenders. However, they have lower phosphorus content than DOPO and therefore have to be applied at considerably higher concentrations.

(Thio)phosphinyliminophosphoranes have been used in preparative elemental organic synthesis, particularly as ligands in transition metal complexes. U.S. Pat. Spec.

3, 189,564 discloses (thio)phosphinyliminophosphoranes, a process for their preparation, and the use of diphenylphosphinyltriphenyliminophosphorane as a flame retardant in an epoxy resin composition cured with an aliphatic triamine. However, U.S. Pat. Spec. 3, 189,564 discloses a low efficiency of this composition with respect to flame retardation. After the second ignition the test samples did not self-extinguish for 90 sec. It has surprisingly been found that thermoplastic or duroplastic polymers with excellent flame retardant properties are prepared in the event that (thio)phosphinyliminophos- phorane compounds are added to the polymer substrate.

These compositions have excellent thermal stability and are therefore especially suited for the application in engineering thermoplastics and epoxy laminates used for the manufacture of electrical and electronic parts and devices. Furthermore, epoxy resins comprising the compounds (I) show no or only a minor negative impact on the glass transition temperature, which is considered advantageous especially for their use in epoxy laminates for the manufacture of printed circuit boards. By using the instant flame retardant additives in thermoplastic and duroplastic resins, conventional halogen containing flame retardants and halogenated epoxy resins, antimony compounds, and inorganic fillers may largely be reduced or replaced.

The invention relates to a composition, particularly a flame retardant composition, which comprises a single component of

Wherein

R1-R5 independently of one another represent

CrC₄-alkyl, C₆-Ci2aryl, (Ci-C₄alkyl)_{1 -3}C6-Ci2aryl, or (Ci-C₄alkoxy)i-₃C6-Ci2aryl;

X represents oxygen or sulphur; and

n represents zero or one; and

b) A polymer substrate, with the proviso that combinations of polyfunc- tional epoxide compounds and hardener compounds that contain at least two aliphatic amino groups, are excluded.

The term phosphinyliminophosphorane comprises within the scope of the description of the present invention the following structural embodiments

Or

(X=S, n=1 )

Or

(n=0)

The above-mentioned phosphinyliminophosphoranes are obtainable by known methods, such as the ones described in U.S. Pat. Spec. 3, 189,564.

CrC₄alkyl is methyl, ethyl, n- or isopropyl, or n-, iso- or tert-butyl.

C₆-Ci₂aryl is, for example, phenyl or naphthyl, e.g. 1- or 2-naphthyl.

(Ci-C₄alkyl)_{1 -3}C6-Ci₂aryl is, for example, phenyl or naphthyl, e.g. 1 - or 2-naphthyl, substituted by the above-mentioned CrC₄alkyl groups.

(Ci-C₄alkoxy)i-₃C6-Ci₂aryl is, for example, phenyl or naphthyl, e.g. 1- or 2-naphthyl, substituted by CrC₄alkoxy groups, such as methoxy or ethoxy.

The invention does not relate to compositions, wherein phosphinyliminophospho- rane (I) compounds, wherein Ri-R₅, X and n are as defined above, are present in the form of a single component in combination with polyfunctional epoxide compounds and hardener compounds that contain at least two aliphatic amino groups.

A preferred embodiment of the invention relates to a composition, which comprises a single component of

a)A phosphinyliminophosphorane (I), wherein Ri-R₅ independently of one another represent Ci-C₄-alkyl or phenyl, X represents oxygen or sulphur and n represents one; and b)A polymer substrate, with the proviso that combinations of polyfunctional epoxide compounds and hardener compounds that contain at least two aliphatic amino groups, are excluded.

A particularly preferred embodiment relates to a composition, which comprises a single component of

a) A phosphinyliminophosphorane (I), wherein Ri-R₅ independently of one another represent phenyl, X represents oxygen and n represents one; and

b) A polymer substrate, with the proviso that combinations of polyfunctional epoxide compounds and hardener compounds that contain at least two aliphatic amino groups, are excluded.

A highly preferred embodiment relates to a composition, which comprises a single component of

a) A phosphinyliminophosphorane (I), wherein Ri-R₅ independently of one another represent phenyl, X represents oxygen and n represents one; and b) At least one polyfunctional epoxide compound; and, optionally, a hardener compound; with the proviso that combinations of polyfunctional epoxide compounds and hardener compounds that contain at least two aliphatic amino groups are excluded.

The polymer compositions wherein the compounds (I), as defined above, are present, attain the desirable V-0 rating, according to UL-94 (Underwriter's Laboratories Subject 94) and other excellent ratings in related test methods, especially in glass fibre reinforced formulations where conventional FR systems tend to fail.

These compounds (I) are preferably contained in the flame retardant compositions according to the invention in an amount from 1.0 - 50.0 wt. %, preferably 2.0 - 30.0 wt. %, based on the total weight of the composition.

The term polymer substrate comprises within its scope thermoplastic and duroplastic polymers and thermosets.

A list of suitable thermoplastic polymers is given below:

1 . Polymers of monoolefins and diolefins, for example polypropylene, polyisobutylene, polybut-1 -ene, poly-4-methylpent-1 -ene, polyvinylcyclohexane, polyisoprene or polybutadiene, as well as polymers of cycloolefins, for instance of cyclopentene or norbornene, polyethylene (which optionally can be cross linked), for example high density polymethylene (HDPE), high density and high molecular weight polyethylene (HDPE-HMW), high density and ultrahigh molecular weight polyethylene (HDPE-UHMW), medium density polyethylene (MDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), (VLDPE) and (ULDPE).

Polyolefins, i.e. the polymers of monoolefins exemplified in the preceding paragraph, preferably polyethylene and polypropylene, can be prepared by different and especially by the following methods:

a) Radical polymerisation (normally under high pressure and at elevated temperature).

b) Catalytic polymerisation using a catalyst that normally contains one or more than one metal of groups IVb, Vb, Vlb or VIII of the Periodic Table. These metals usually have one or more than one ligand, typically oxides, halides, alcoholates, esters, ethers, amines, alkyls, alkenyls and/or aryls that may be either o- or ττ-bond coordinated. These metal complexes may be in the free form or fixed on substrates, typically on activated magnesium chloride, titanium(lll) chloride, alumina or silicon oxide. These catalysts may be soluble or insoluble in the polymerisation medium. The catalysts can be used by themselves in the polymerisation or further activators may be used, typically metal alkyls, metal hydrides, metal alkyl halides, metal alkyl oxides or metal alkyloxanes, said metals being elements of groups la, I la and/or Ilia of the Periodic Table. The activators may be modified conveniently with further ester, ether, and amine or silyl ether groups. These catalyst systems are usually termed Phillips, Standard Oil Indiana, Ziegler-Natta), TNZ (DuPont), metallocene or single site catalysts (SSC).

Mixtures of the polymers mentioned under 1 ), for example mixtures of polypropylene with polyisobutylene, polypropylene with polyethylene (for example PP/HDPE, PP/LDPE) and mixtures of different types of polyethylene (for example

LDPE/HDPE).

Copolymers of monoolefins and diolefins with each other or with other vinyl monomers, for example ethylene/propylene copolymers, linear low density polyethylene (LLDPE) and mixtures thereof with low density polyethylene (LDPE), propylene/but- 1 -ene copolymers, propylene/isobutylene copolymers, ethylene/but-1 -ene copolymers, ethylene/hexene copolymers, ethylene/methylpentene copolymers, ethyl- ene/heptene copolymers, ethylene/octene copolymers, ethylene/vinylcyclohexane copolymers, ethylene/cycloolefin copolymers (e.g. ethylene/norbornene like COC), ethylene/1 -olefins copolymers, where the 1 -olefin is generated in-situ; propyl- ene/butadiene copolymers, isobutylene/isoprene copolymers, ethylene/vinylcyclo- hexene copolymers, ethylene/alkyl acrylate copolymers, ethylene/alkyl methacry- late copolymers, ethylene/vinyl acetate copolymers or ethylene/acrylic acid copol- ymers and their salts (ionomers) as well as terpolymers of ethylene with propylene and a diene such as hexadiene, dicyclopentadiene or ethylidene-norbornene; and mixtures of such copolymers with one another and with polymers mentioned in 1 ) above, for example polypropylene/ethylene-propylene copolymers, LDPE/ethylene- vinyl acetate copolymers (EVA), LDPE/ethylene-acrylic acid copolymers (EAA), LLDPE/EVA, LLDPE/EAA and alternating or random polyalkylene/carbon monoxide copolymers and mixtures thereof with other polymers, for example polyamides.

Hydrocarbon resins (for example C₅-C₉) including hydrogenated modifications thereof (e.g. tackifiers) and mixtures of polyalkylenes and starch;

The homopolymers and copolymers mentioned above may have a stereo structure including syndiotactic, isotactic, hemi-isotactic or atactic; where atactic polymers are preferred. Stereo block polymers are also included.

Polystyrene, poly(p-methylstyrene), poly(a-methylstyrene).

Aromatic homopolymers and copolymers derived from vinyl aromatic monomers including styrene, omethylstyrene, all isomers of vinyl toluene, especially p-vinyl toluene, all isomers of ethyl styrene, propyl styrene, vinyl biphenyl, vinyl naphthalene, and vinyl anthracene, and mixtures thereof. Homopolymers and copolymers may have a stereo structure including syndiotactic, isotactic, hemi-isotactic or atactic; where atactic polymers are preferred. Stereo block polymers are also included; a) Copolymers including afore-mentioned vinyl aromatic monomers and como- nomers selected from ethylene, propylene, dienes, nitriles, acids, maleic anhydrides, maleimides, vinyl acetate and vinyl chloride or acrylic derivatives and mixtures thereof, for example styrene/butadiene, styrene/acrylonitrile, styrene/ethylene (interpolymers), styrene/alkyl methacrylate, styrene/buta- diene/alkyl acrylate, styrene/butadiene/alkyl methacrylate, styrene/maleic anhydride, styrene/acrylonitrile/methyl acrylate; mixtures of high impact strength of styrene copolymers and another polymer, for example a poly- acrylate, a diene polymer or an ethylene/propylene/diene terpolymer; and block copolymers of styrene such as styrene/butadiene/styrene, styrene/iso- prene/styrene, styrene/ethylene/butylene/styrene or styrene/ethylene/propy- lene/styrene.

b) Hydrogenated aromatic polymers derived from hydrogenation of polymers mentioned under 6.), especially including polycyclohexylethylene (PCHE) prepared by hydrogenating atactic polystyrene, often referred to as polyvi- nylcyclohexane (PVCH). c) Hydrogenated aromatic polymers derived from hydrogenation of polymers mentioned under 6a). Homopolymers and copolymers may have a stereo structure including syndiotactic, isotactic, hemi-isotactic or atactic; where atactic polymers are preferred. Stereo block polymers are also included. 7. Graft copolymers of vinyl aromatic monomers, such as styrene or omethylstyrene, for example styrene on polybutadiene, styrene on polybutadiene-styrene or poly- butadiene-acrylonitrile copolymers; styrene and acrylonitrile (or methacrylonitrile) on polybutadiene; styrene, acrylonitrile and methyl methacrylate on polybutadiene; styrene and maleic anhydride on polybutadiene; styrene, acrylonitrile and maleic anhydride or maleimide on polybutadiene; styrene and maleimide on polybutadiene; styrene and alkyl acrylates or methacrylates on polybutadiene; styrene and acrylonitrile on ethylene/propylene/diene terpolymers; styrene and acrylonitrile on polyalkyl acrylates or polyalkyl methacrylates, styrene and acrylonitrile on acry- late/butadiene copolymers, as well as mixtures thereof with the copolymers listed under 6), for example the copolymer mixtures known as ABS, MBS, ASA or AES polymers.

8. Halogen-containing polymers such as polychloroprene, chlorinated rubbers, chlorinated and brominated copolymer of isobutylene-isoprene (halobutyl rubber), chlorinated or sulphochlorinated polyethylene, copolymers of ethylene and chlorinated ethylene, epichlorohydrin homo- and copolymers, especially polymers of halogen- containing vinyl compounds, for example polyvinyl chloride, polyvinylidene chloride, polyvinyl fluoride, polyvinylidene fluoride, as well as copolymers thereof such as vinyl chloride/vinylidene chloride, vinyl chloride/vinyl acetate or vinylidene chloride/vinyl acetate copolymers.

9. Polymers derived from α,β-unsaturated acids and derivatives thereof such as poly- acrylates and polymethacrylates; polymethyl methacrylates, polyacrylamides and polyacrylonitriles, impact-modified with butyl acrylate.

10. Copolymers of the monomers mentioned under 9) with each other or with other unsaturated monomers, for example acrylonitrile/ butadiene copolymers, acryloni- trile/alkyl acrylate copolymers, acrylonitrile/alkoxyalkyl acrylate or acrylonitrile/vinyl halide copolymers or acrylonitrile/ alkyl methacrylate/butadiene terpolymers.

1 1 . Polymers derived from unsaturated alcohols and amines or the acyl derivatives or acetals thereof, for example polyvinyl alcohol, polyvinyl acetate, polyvinyl stearate, polyvinyl benzoate, polyvinyl maleate, polyvinyl butyral, polyallyl phthalate or poly- allyl melamine; as well as their copolymers with olefins mentioned in 1 above. 12. Homopolymers and copolymers of cyclic ethers such as polyalkylene glycols, polyethylene oxide, polypropylene oxide or copolymers thereof with bisglycidyl ethers.

13. Polyacetals such as polyoxymethylene and those polyoxymethylenes, which contain ethylene oxide as a co-monomer; polyacetals modified with thermoplastic poly- urethanes, acrylates or MBS.

14. Polyphenylene oxides and sulphides, and mixtures of polyphenylene oxides with styrene polymers or polyamides.

15. Polyurethanes derived from hydroxyl-terminated polyethers, polyesters or polybuta- dienes on the one hand and aliphatic or aromatic polyisocyanates on the other, as well as precursors thereof.

16. Polyamides and co-polyamides derived from diamines and dicarboxylic acids and/- or from aminocarboxylic acids or the corresponding lactams, for example polyami- de 4, polyamide 6, polyamide 6/6, 6/10, 6/9, 6/12, 4/6, 12/12, polyamide 1 1 , poly- amide 12, aromatic polyamides starting from m-xylene diamine and adipic acid; polyamides prepared from hexamethylenediamine and isophthalic or/and tereph- thalic acid and with or without an elastomer as modifier, for example poly-2,4,4,- trimethylhexamethylene terephthalamide or poly-m-phenylene isophthalamide; and also block copolymers of the aforementioned polyamides with polyolefins, olefin copolymers, ionomers or chemically bonded or grafted elastomers; or with polyeth- ers, e.g. with polyethylene glycol, polypropylene glycol or polytetramethylene glycol; as well as polyamides or co-polyamides modified with EPDM or ABS; and polyamides condensed during processing (RIM polyamide systems).

17. Polyureas, polyimides, polyamide imides, polyether imides, polyester imides, poly- hydantoins and polybenzimidazoles.

18. Polyesters derived from dicarboxylic acids and diols and/or from hydroxycarboxylic acids or the corresponding lactones, for example polyethylene terephthalate, poly- butylene terephthalate, poly-1 ,4-dimethylolcyclohexane terephthalate, polyalkylene naphthalate (PAN) and polyhydroxybenzoates, as well as block co-polyether esters derived from hydroxyl-terminated polyethers; and also polyesters modified with pol- ycarbonates or MBS.

19. Polyketones.

20. Polysulphones, polyether sulphones and polyether ketones.

21 . Blends of the aforementioned polymers (polyblends), for example PP/EPDM, Poly- amide/EPDM or ABS, PVC/EVA, PVC/ABS, PVC/MBS, PC/ABS, PBTP/ABS, PC/ASA, PC/PBT, PVC/CPE, PVC/acrylates, POM/thermoplastic PUR, PC/thermo- plastic PUR, POM/acrylate, POM/MBS, PPO/HIPS, PPO/PA 6.6 and copolymers, PA/HDPE, PA/PP, PA/PPO, PBT/PC/ABS or PBT/PET/PC.

Polycarbonates that correspond to the general formula:

R-O-C-O-

-t- Jn

o

Such polycarbonates are obtainable by interfacial processes or by melt processes (catalytic transesterification). The polycarbonate may be either branched or linear in structure and may include any functional substituents. Polycarbonate copolymers and polycarbonate blends are also within the scope of the invention. The term polycarbonate should be interpreted as inclusive of copolymers and blends with other thermoplastics. Methods for the manufacture of polycarbonates are known, for example, from U.S. Patent Specification Nos. 3,030,331; 3, 169, 121; 4, 130,458; 4,263,201; 4,286,083; 4,552, 704; 5,210,268; and 5,606,007. A combination of two or more polycarbonates of different molecular weights may be used.

Preferred are polycarbonates obtainable by reaction of a diphenol, such as bi- s henol A, with a carbonate source. Examples of suitable diphenols are:

sphenol B:

bisphenol P:

bisphenol

, 4,4'-(2-norbornylidene)bis(2,6- dichloro henol); or fluorene-9-bisphenol:

The carbonate source may be a carbonyl halide, a carbonate ester or a halofor- mate. Suitable carbonate halides are phosgene or carbonylbromide. Suitable carbonate esters are dialkylcarbonates, such as dimethyl- or diethylcarbonate, diphen- yl carbonate, phenyl-alkylphenylcarbonate, such as phenyl-tolylcarbonate, dialkylcarbonates, such as dimethyl- or diethylcarbonate, di-(halophenyl)carbonates, such as di-(chlorophenyl)carbonate, di-(bromophenyl)carbonate, di-(trichlorophenyl)- carbonate or di-(trichlorophenyl)carbonate, di-(alkylphenyl)carbonates, such as di- tolylcarbonate, naphthylcarbonate, dichloronaphthylcarbonate and others.

The polymer substrate mentioned above, which comprises polycarbonates or polycarbonate blends is a polycarbonate-copolymer, wherein isophthalate/terephtha- late-resorcinol segments are present. Such polycarbonates are commercially available, e.g. Lexan® SLX (General Electrics Co. USA). Other polymeric substrates of component b) may additionally contain in the form as admixtures or as copolymers a wide variety of synthetic polymers including polyolefins, polystyrenes, polyesters, polyethers, polyamides, poly(meth)acrylates, thermoplastic polyurethanes, polysul- phones, polyacetals and PVC, including suitable compatibilizing agents. For example, the polymer substrate may additionally contain thermoplastic polymers selected from the group of resins consisting of polyolefins, thermoplastic polyurethanes, sty- rene polymers and copolymers thereof. Specific embodiments include polypropylene (PP), polyethylene (PE), polyamide (PA), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), glycol-modified polycyclohexylenemethylene terephthalate (PCTG), polysulphone (PSU), polymethylmethacrylate (PMMA), thermoplastic polyurethane (TPU), acrylonitrile-butadiene-styrene (ABS), acrylonitrile- styrene-acrylic ester (ASA), acrylonitrile-ethylene-propylene-styrene (AES), sty- rene-maleic anhydride (SMA) or high impact polystyrene (HIPS).

A preferred embodiment of the invention relates to a composition, wherein component b) is a duroplastic polymer substrate of the polyepoxide type.

Suitable polyfunctional epoxide compounds are epoxides, wherein at least two epoxy groups of the partial formula

are present, which are attached directly to carbon, oxygen, nitrogen or sulphur atoms, and wherein q represents zero, Ri and R₃ both represent hydrogen and R₂ represents hydrogen or methyl; or wherein q represents zero or 1 , R-i and R₃ together form the -CH2-CH2- or -CH2-CH2-CH2- groups and R₂ represents hydrogen.

Examples of polyfunctional epoxide compounds are:

I) Polyglycidyl esters and poly(3-methylglycidyl) esters obtainable by reacting a compound having at least two carboxyl groups in the molecule with epichloro- hydrin and/or glyceroldichlorohydrin and/or β-methylepichlorohydrin. The reaction is carried out in the presence of bases. Suitable compounds having at least two carboxyl groups in the molecule are aliphatic polycarboxylic acids, such as glutaric, adipic, pimelic, suberic, azelaic, sebacic or dimerized or trimerized linoleic acid. Cycloaliphatic polycarboxylic acids are suitable, e.g. tetrahydrophthalic, 4-methyltetrahydrophthalic, hexahy- drophthalic or 4-methylhexahydrophthalic acid.

Aromatic polycarboxylic acids are suitable, such as phthalic, isophthalic, trimellitic and pyromellitic acid. Likewise suitable are carboxyl-terminated ad- ducts of, for example, trimellitic acid and polyols such as glycerol or 2,2-bis(4- hydroxycyclohexyl)propane.

II) Polyglycidyl ethers or poly(3-methylglycidyl) ethers obtainable by reacting a compound having at least two free alcoholic hydroxyl groups and/or phenolic hydroxyl groups with a suitably substituted epichlorohydrin under alkaline conditions or in the presence of an acidic catalyst with subsequent treatment under alkaline conditions.

Ethers of this type are derived, for example, from straight-chained alcohols, such as ethyleneglycol, diethyleneglycol and higher poly(oxyethylene) glycols, propane-1 ,2-diol, or poly(oxypropylene) glycols, propane-1 ,3-diol, butane-1 ,4- diol, poly(oxytetramethylene) glycols, pentane-1 ,5-diol, hexane-1 ,6-diol, hex- ane-2,4,6-triol, glycerol, 1 ,1 ,1 -trimethylolpropane, bistrimethylolpropane, penta- erythritol, sorbitol, and from polyepichlorohydrins.

In the alternative, they are derived, for example, from cycloaliphatic alcohols, such as 1 ,3- or 1 ,4-dihydroxycyclohexane, bis(4-hydroxycyclohexyl)methane, 2,2-bis(4-hydroxycyclohexyl)-propane or 1 ,1 -bis(hydroxymethyl)cyclohex-3-ene, or they possess aromatic nuclei, such as N,N-bis(2-hydroxyethyl)aniline or ρ,ρ'- bis(2-hydroxyethylamino)diphenylmethane.

The epoxy compounds may also be derived from mononuclear phenols, such as resorcinol or hydroquinone; or they are based on polynuclear phenols, such as bis(4-hydroxyphenyl)methane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(3,5- dibromo-4-hydroxyphenyl)-propane or 4,4'-dihydroxydiphenyl sulphone, or on condensates of phenols with formaldehyde that are obtained under acidic conditions, such as phenol Novolak®.

Ill) Poly(N-glycidyl) compounds obtainable by dehydrochlorinating the reaction products of epichlorohydrin with amines containing at least two amino hydrogen atoms. These amines are, for example, aniline, toluidine, n-butylamine, bis(4- aminophenyl)methane, m-xylylenediamine or bis(4-methylaminophenyl)me- thane, and also Ν,Ν,Ο-triglycidyl-m-aminophenol or N,N,0-triglycidyl-p-amino- phenol. The poly(N-glycidyl) compounds also include Ν,Ν'-diglycidyl derivatives of cy- cloalkylene-urea, such as ethylene urea or 1 ,3-propyleneurea, and N,N'-di- glycidyl derivatives of hydantoins, such as of 5,5-dimethylhydantoin.

IV) Poly(S-glycidyl) compounds, such as di-S-glycidyl derivatives derived from dithi- ols, such as ethane-1 ,2-dithiol or bis(4-mercaptomethylphenyl) ether.

Epoxy compounds having a radical of the partial formula above, in which R-i and R₃ together are -CH₂-CH₂- and q is 0, are bis(2,3-epoxycyclopentyl) ether, 2,3-epoxycyclo- pentyl glycidyl ether or 1 ,2-bis(2,3-epoxycyclopentyloxy) ethane. An example of an epoxy resin having a radical of the partial formula above in which R-i and R₃ together are -CH₂-CH₂- and q is 1 is (3,4-epoxy-6-methylcyclohexyl)methyl 3',4'-epoxy-6'- methylcyclohexanecarboxylate.

Polyfunctional epoxide compounds are known. Many of them are commercially available from Huntsman Advanced Materials (brand name Araldite®). Examples of suitable polyfunctional epoxides are:

a) Liquid bisphenol A diglycidyl ethers, such as ARALDITE GY 240, ARALDITE GY 250, ARALDITE GY 260, ARALDITE GY 266, ARALDITE GY 2600, ARALDITE MY 790, DER^® 332, DER331 , Hexion^® EPR 158, Tactix^® 123, TACTIX138, Epon^® 826; b) Solid bisphenol A diglycidyl ethers such as ARALDITE GT 6071 , ARALDITE GT 7071 , ARALDITE GT 7072, ARALDITE GT 6063, ARALDITE GT 7203, ARALDITE GT 6064, ARALDITE GT 7304, ARALDITE GT 7004, ARALDITE GT 6084, ARALDITE GT 1999, ARALDITE GT 7077, ARALDITE GT 6097, ARALDITE GT 7097, ARALDITE GT 7008, ARALDITE GT 6099, ARALDITE GT 6608, ARALDITE GT 6609, ARALDITE GT 6610, ARALDITE CT 200, ARALDITE 6100 ES, Epikote^® 1001 , EPIKOTE 109, DER^® 661 , DER 667, DER 668, DLS 1065 ES;

c) Liquid bisphenol F diglycidyl ethers, such as ARALDITE GY 281 , ARALDITE

GY 282, ARALDITE PY 302, ARALDITE PY 306;

d) Solid polyglycidyl ethers of tetraphenylethane, such as CG Epoxy Resin^D0163; e) Solid and liquid polyglycidyl ethers of phenol-formaldehyde Novolak®, such as EPN 1 138, EPN 1 139, GY 1 180, PY 307, EPON 828, TACTIX 556;

f) Solid and liquid polyglycidyl ethers of o-cresol-formaldehyde NOVOLAK, such as ECN 1235, ECN 1273, ECN 1280, ECN 1299;

g) Liquid glycidyl ethers of alcohols, such as Shell^Dglycidyl ether 162, ARALDITE DY 0390, ARALDITE DY 0391 ; h) Liquid glycidyl ethers of carboxylic acids, such as Shell Cardura E terephthalic ester, trimellitic ester, ARALDITE PY 284;

i) Solid heterocyclic epoxy resins (triglycidyl isocyanurate), such as ARALDITE PT 810; k) Liquid cycloaliphatic epoxy resins, such as ARALDITE CY 179;

I) Liquid Ν,Ν,Ο-triglycidyl ethers of p-aminophenol, such as ARALDITE MY 0510;

m) Tetraglycidyl-4,4'-methylenebenzamine or Ν,Ν,Ν',Ν'-tetraglycidyldiaminophenylme- thane, such as ARALDITE MY 720, ARALDITE MY 721 ;

n) N,N,N',N'-tetraglycidyl-m-xylidenediamine, such as Tetrad^®-X;

o) Triglycidyl ether of 1 ,1 ,2,-tris(4-hydroxyphenyl)ethane, such as Tactix^® 742.

If desired, a mixture of epoxy compounds of different structure can also be employed.

Suitable hardener compounds are any of the known hardeners for epoxy resins, particularly the ones commercially available. The amine, phenolic and anhydride hardeners are particularly preferred, such as polyamines, e.g. ethylenediamine, diethylenetri- amine, triethylenetetramine, hexamethylenediamine, methanediamine, N-amino-'ethyl piperazine, diaminodiphenyhmethane [DDM], alkyl-substituted derivatives of DDM, isophoronediamine [IPD], diam nod phen-'ylsulphone [DDS], 4,4-methylenedianiline [MDA], or m phenyhenediamine [MPDA]), polyamides, alkyl/alkenyl imidazoles, dicy- anodiamide [DICY], I .B-hexame-'thylene-bis-cyanogua-nidine, phenolic hardeners such as phenol novolac and cresol novolac, and acid anhydrides, e.g. dodecen- ylsuc-Oinic acid anhydride, hexahydrophthalic acid anhydride, tet-rahydrcnphthalic acid an-'hydride, phthalic acid anhydride, pyromellitic acid anhydride, styrene-maleic acid anhydride copolymers, and derivatives thereof.

According to a preferred embodiment, the composition comprises as component b) a thermoplastic polymer substrate selected from the group consisting of polyamides, pol- yesters and polycarbonates.

A preferred embodiment of the invention relates to a composition, which comprises as component b) a polyfunctional epoxide compound and a phenolic hardener compound that contains at least two phenolic groups, such as phenol novolac.

A particularly preferred embodiment of the invention relates to a composition, which comprises

a) About 0.05 - 30.0 wt. % (I) of at least one phosphinyliminophosphorane (I),

wherein Ri-R₅, X and n are as defined above;

b) About 60.0 - 95.0 wt. % of a polyfunctional epoxide compound; and 0.10 - 40.0 wt. % of a hardener compound. The invention also relates to a process for imparting flame retardancy to a polymer substrate, which comprises adding to the polymer substrate as the flame retardant the phosphinyliminophosphorane of the formula

Wherein

R1-R5 independently of one another represent

X represents oxygen or sulphur; and

n represents zero or one; as single component,

with the proviso that combinations of polyfunctional epoxide compounds and hardener compounds that contain at least two aliphatic amino groups are excluded.

The instant invention further pertains to the use of compounds (I) in flame retardant compositions which comprise, in addition to the components defined above, optional components, such as further additives selected from the group consisting of tetra- alkylpiperidine additives, polymer stabilizers, fillers, reinforcing agents and so-called anti-dripping agents that reduce the melt flow of thermoplastic polymers and reduce the formation of drops at higher temperatures.

A preferred embodiment of the invention relates to the process for imparting flame re- tardancy to a polymer substrate, which comprises adding to the polymer substrate a combination of a phosphinyliminophosphorane of the formula

Wherein

R1-R5 independently of one another represent CrC₄-alkyl, C₆-Ci2aryl,(Ci-C₄alkyl)_{1 -3}C6-Ci2aryl or (Ci-C₄alkoxy)i-₃C6-Ci2aryl;

X represents oxygen or sulphur; and

n represents zero or one;

with at least one additional flame retardant.

A further embodiment of the invention relates to a composition which comprises

a) A combination of a phosphinyliminophosphorane of the formula

Wherein

R1-R5 independently of one another represent

CrC₄-alkyl, C₆-Ci2aryl, (Ci-C₄alkyl)_{1 -3}C6-Ci2aryl or (Ci-C₄alkoxy)i-₃C6-Ci2aryl; with at least one additional flame retardant; and

b) A polymer substrate.

A particularly preferred embodiment relates to the above-mentioned composition, which comprises a) a combination of a phosphinyliminophosphorane (I), wherein R1-R5 independently of one another represent Ci-C₄-alkyl or phenyl, X represents oxygen or sulphur and n represents one; with at least one additional flame retardant selected from the group consisting of phosphorus containing flame retardants, nitrogen containing flame retardants, nitrogen and phosphorus containing flame retardants, organohalogen containing flame retardants and inorganic flame retardants.

A particularly preferred embodiment relates to a composition, which comprises a) a combination of a phosphinyliminophosphorane (I), wherein R1-R5 independently of one another represent phenyl, X represents oxygen and n represents one; with at least one additional flame retardant selected from the group consisting of phosphorus containing flame retardants, nitrogen containing flame retardants, nitrogen and phosphorus containing flame retardants, organohalogen containing flame retardants and inorganic flame retardants. Phosphorus containing flame retardants are, for example, tetraphenyl resorcinol diphosphate, resorcinol phenylphosphate oligomer (Fyrolflex^® RDP, Akzo Nobel), tri- phenyl phosphate, bisphenol A phenylphosphate oligomer (Fyrolflex® BDP), tris(2,4-di- tert-butylphenyl)phosphate, ethylenediamine diphosphate (EDAP), tetra(2,6-dimeth- ylphenyl) resorcinol diphosphate, ammonium polyphosphate, diethyl-N,N-bis(2-hydrox- yethyl)-aminomethyl phosphonate, hydroxyalkyl esters of phosphorus acids, salts of di- CrC₄alkylphosphinic acids and of hypophosphoric acid (H₃P0₂), particularly the Ca²⁺, Zn²⁺, or Al³⁺ salts, tetrakis(hydroxymethyl)phosphonium sulphide, triphenylphosphine, triphenylphosphine oxide, tetraphenyldiphosphine monoxide, phosphazenes and 9,10- dihydro-9-oxa-10-phosphorylphenanthrene-10-oxide (DOPO) and its derivatives, such as 2-(9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide)-1 ,4-benzenediol.

Nitrogen containing flame retardants are, for example, benzoguanamine, allantoin, gly- coluril, urea cyanurate, melamine cyanurate, melamine borate, isocyanurate flame retardants, such as polyisocyanurate, esters of isocyanuric acid or isocyanurates. Repre- sentative examples are hydroxyalkyl isocyanurates, such as tris-(2-hydroxyethyl)iso- cyanurate, tris(hydroxymethyl)isocyanurate, tris(3-hydroxy-n-proyl)isocyanurate or tri- glycidyl isocyanurate.

Nitrogen and phosphorus containing flame-retardants include ammonium polyphosphate and melamine-based flame-retardants. Representative examples are: melamine phosphate, melamine pyrophosphate, melamine polyphosphate, melamine ammonium polyphosphate, melamine ammonium pyrophosphate, dimelamine phosphate, dimela- mine pyrophosphate and condensations product of melamine from the series melem, melam, melon and/or a higher condensed compound or a reaction product of melamine with phosphoric acid or a mixture thereof

Representative organohalogen flame retardants are, for example:

Polybrominated diphenyl oxide (DE-60F, Great Lakes Corp.), decabromodiphenyl oxide (DBDPO; Saytex^® 102E), tris[3-bromo-2,2-bis(bromomethyl)propyl] phosphate (PB 370^®, FMC Corp.), tris(2,3-dibromopropyl)phosphate, tris(2,3-dichloropropyl)phospha- te, chlorendic acid, tetrachlorophthalic acid, tetrabromophthalic acid, polychloroethyl triphosphonate mixture, tetrabromobisphenol A bis(2,3-dibromopropyl ether) (PE68), brominated epoxy resin, ethylene-bis(tetrabromophthalimide) (Saytex^® BT-93), bis(he- xachlorocyclopentadieno) cyclooctane (Declorane Plus^®), chlorinated paraffins, octa- bromodiphenyl ether, 1 ,2-bis(tribromophenoxy)ethane (FF680), tetrabromo-bisphenol A (Saytex^® RB100), ethylene bis-(dibromo-norbornanedicarboximide) (Saytex^® BN-451 ), bis-(hexachlorocyclopentadieno) cyclooctane, PTFE, tris-(2,3-dibromopropyl)-isocyan- urate, and ethylene-bis-tetrabromophthalimide. The organohalogen flame retardants mentioned above are routinely combined with an inorganic oxide synergist. Most common for this use are zinc or antimony oxides, e.g. Sb₂0₃ or Sb₂0₅. Boron compounds are suitable, too.

Representative inorganic flame retardants include, for example, aluminium trihydroxide (ATH), boehmite (AIOOH), magnesium dihydroxide (MDH), hydrotalcite, zinc borates, CaC0₃, (organically modified) layered silicates, (organically modified) layered double hydroxides, polyhedral oligomeric silsesquioxanes, and mixtures thereof.

The above-mentioned additional flame retardant classes are advantageously contained in the composition of the invention in an amount from about 0.5% to about 75.0%; for instance about 1.0% to about 70.0%; for example about 2.0% to about 50.0% by weight, based on the total weight of the composition.

The combination of phosphinyliminophosphorane (I) and the additional flame retardant is preferably contained in the flame retardant compositions defined above in an amount from 1.0 - 80.0 wt.%, preferably 2.0 - 55.0 wt.%, based on the total weight of the com- position.

A preferred embodiment relates to a composition, which comprises a) a combination of a phosphinyliminophosphorane (I), wherein Ri-R₅ independently of one another represent phenyl, X represents oxygen and n represents one; with at least one additional flame retardant selected from the group consisting of

· Phosphorus containing flame retardants selected from the group consisting of tet- ra(2,6-dimethylphenyl)resorcinol diphosphate, oligomeric resorcinol methyl- phosphonate, salts of di-CrC₄alkylphosphinic acid, salts of hypophosphoric acid and 9,10-dihydro-9-oxa-10-phosphorylphenanthrene-10-oxide (DOPO) and its derivatives;

· Nitrogen and phosphorus containing flame retardants selected from the group consisting of melamine polyphosphate, ammonium polyphosphate, melamine ammonium phosphate, melamine ammonium polyphosphate, melamine ammonium pyrophosphate, a condensation product of melamine with phosphoric acid and other reaction products of melamine with phosphoric acid and mixtures thereof;

• Organohalogen containing flame retardants selected from the group consisting of polybrominated diphenyl oxide, decabromodiphenyl oxide, tris[3-bromo-2,2- bis(bromomethyl)propyl]phosphate, tris(2,3-dibromopropyl)phosphate, tris(2,3-di- chloropropyl)phosphate, tetrabromophthalic acid, tetrabromobisphenol A and bis(2,3-dibromopropyl ether); and • Inorganic flame retardants selected from the group consisting of aluminium trihy- droxide (ATH), boehmite (AIOOH), magnesium dihydroxide (MDH), hydrotalcite, zinc borates, CaC0₃, (organically modified) layered silicates and (organically modified) layered double hydroxides, polyhedral oligomeric silsesquioxanes, and mixtures thereof.

According to a further embodiment of the invention, the compositions comprise as optional components additives selected from the group consisting of tetraalkylpiperidine additives, polymer stabilizers, fillers, reinforcing agents and so-called anti-dripping agents that reduce the melt flow of thermoplastic polymers and reduce the formation of drops at higher temperatures.

These anti-dripping agents reduce the melt flow of the thermoplastic polymer and inhibit the formation of drops at high temperatures. Various references, such as U.S. Patent Specification No. 4,263,201, describe the addition of anti-dripping agents to flame retardant compositions.

Suitable additives that inhibit the formation of drops at high temperatures include glass fibres, polytetrafluoroethylene (PTFE), high temperature elastomers, carbon fibres, glass spheres and the like.

The addition of polysiloxanes of different structures has been proposed in various references; cf. U.S. Pat. Spec. Nos. 6,660, 787, 6, 727,302 or 6, 730, 720.

According to a further embodiment, the invention relates to compositions which additionally comprise as additional components fillers and reinforcing agents. Suitable fillers are, for example, glass powder, glass microspheres, silica, mica and talcum.

Stabilizers are preferably halogen-free and selected from the group consisting of nitro- xyl stabilizers, nitrone stabilizers, amine oxide stabilizers, benzofuranone stabilizers, phosphite and phosphonite stabilizers, quinone methide stabilizers and monoacrylate esters of 2,2'-alkylidenebisphenol stabilizers.

As mentioned above, the composition according to the invention may additionally contain one or more conventional additives, for example selected from pigments, dyes, plasticizers, antioxidants, thixotropic agents, levelling assistants, basic co-stabilizers, metal passivators, metal oxides, organophosphorus compounds, further light stabilizers and mixtures thereof, especially pigments, phenolic antioxidants, calcium stearate, zinc stearate, UV absorbers of the 2-hydroxy-benzophenone, 2-(2'-hydroxyphenyl)benzotri- azole and/or 2-(2-hydroxyphenyl)-1 ,3,5-triazine groups.

Preferred additional additives for the compositions as defined above are processing stabilizers, such as the above-mentioned phosphites and phenolic antioxidants, and light stabilizers, such as benzotriazoles. Preferred specific antioxidants include octade- cyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (IRGANOX 1076), pentaerythritol- tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (IRGANOX 1010), tris(3,5-di- tert-butyl-4-hydroxyphenyl)isocyanurate (IRGANOX 31 14), 1 ,3,5-trimethyl-2,4,6- tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene (IRGANOX 1330), triethyleneglycol- bis[3-(3- tert-butyl-4-hydroxy-5-methylphenyl)propionate] (IRGANOX 245), and Ν,Ν'- hexane-1 ,6-diyl-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionamide] (IRGANOX 1098). Specific processing stabilizers include tris(2,4-di-tert-butylphenyl)phosphite (IRGAFOS 168), 3,9-bis(2,4-di-tert-butylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphas- piro[5.5]undecane (IRGAFOS 126), 2,2',2"-nitrilo[triethyl-tris(3,3',5,5'-tetra-tert-butyl- 1 ,1 '-biphenyl-2,2'-diyl)]phosphite (IRGAFOS 12), and tetrakis(2,4-di-tert-butylphenyl)- [1 ,1 -biphenyl]-4,4'-diylbisphosphonite (IRGAFOS P-EPQ). Specific light stabilizers include 2-(2H-benzotriazole-2-yl)-4,6-bis(1 -methyl-1-phenylethyl)phenol (TINUVIN 234), 2-(5-chloro(2H)-benzotriazole-2-yl)-4-(methyl)-6-(tert-butyl)phenol (TINUVIN 326), 2- (2H-benzotriazole-2-yl)-4-(1 ,1 ,3,3-tetramethylbutyl)phenol (TINUVIN 329), 2-(2H-ben- zotriazole-2-yl)-4-(tert-butyl)-6-(sec-butyl)phenol (TINUVIN 350), 2,2'-methylenebis(6- (2H-benzotriazol-2-yl)-4-(1 ,1 ,3,3-tetramethylbutyl)phenol) (TINUVIN 360), and 2-(4,6- diphenyl-1 ,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol (TINUVIN 1577), 2-(2'-hydroxy-5'- methylphenyl)benzotriazole (TINUVIN P), 2-hydroxy-4-(octyloxy)benzophenone (CHI- MASSORB 81 ), 1 ,3-bis-[(2'-cyano-3',3^,-diphenylacryloyl)oxy]-2,2-bis-{[(2^,-cyano- 3',3'- diphenylacryloyl)oxy]methyl}-propane (UVINUL 3030, BASF), ethyl-2-cyano-3,3-di- phenylacrylate (UVINUL 3035, BASF), and (2-ethylhexyl)-2-cyano-3,3-diphenylacrylate (UVINUL 3039, BASF).

According to a further embodiment the compositions comprise as an optional compo- nent the additional flame retardants defined above and additives selected from the group consisting of polymer stabilizers and tetraalkylpiperidine derivatives.

Representative examples of tetraalkylpiperidine derivatives are selected from the group consisting of

1 -Cyclohexyloxy-2,2,6,6-tetramethyl-4-octadecylaminopiperidine,

bis(1 -Octyloxy-2,2,6,6-tetramethylpiperidin-4-yl) sebacate,

2,4-bis[(1 -Cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-6-(2-hy- droxyethylamino-s-triazine,

bis(1 -Cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl) adipate,

2,4-bis[(1 -Cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-6-chloro- s-triazine, 1 -(2-Hydroxy-2-methylpropoxy)-4-hydroxy-2,2,6,6-tetramethylpiperidine,

1 -(2-Hydroxy-2-methylpropoxy)-4-oxo-2,2,6,6-tetramethylpiperidine,

1 -(2-Hydroxy-2-methylpropoxy)-4-octadecanoyloxy-2,2,6,6-tetramethylpiperi- dine,

bis(1 -(2-Hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl) sebacate, bis(1 -(2-Hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl) adipate,

2,4-bis{N-[1 -(2-Hydroxy-2-methylpropoxy)-2,2,6,6-tetramethylpiperidin-4-yl]-N- butylamino}-6-(2-hydroxyethylamino)-s-triazine,

The reaction product of 2,4-bis[(1 -cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4- yl)butylamino]-6-chloro-s-triazine with N,N'-bis(3-aminopropyl)ethylenediamine),

2,4-bis[(1 -Cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-6-(2-hy- droxyethylamino)-s-triazine,

The oligomeric compound which is the condensation product of 4,4'-hexameth- ylenebis(amino-2,2,6,6-tetramethylpiperidine) and 2,4-dichloro-6-[(1 -cyclohexyl- oxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-s-triazine end-capped with 2- chloro-4,6-bis(dibutylamino)-s-triazine,

The compound of the formula

And the compound of the formula

in which n is from 1 to 15.

The additives mentioned above are preferably contained in an amount of 0.01 to 10.0%, especially 0.05 to 5.0%, relative to the weight of the polymer substrate of Com- ponent b).

The incorporation of the components defined above into the polymer component is carried out by known methods such as dry blending in the form of a powder, or wet mixing in the form of solutions, dispersions or suspensions for example in an inert solvent, water or oil. The additive components may be incorporated, for example, before or after molding or also by applying the dissolved or dispersed additive or additive mixture to the polymer material, with or without subsequent evaporation of the solvent or the suspension/dispersion agent. They may be added directly into the processing apparatus (e.g. extruders, internal mixers, etc.), e.g. as a dry mixture or powder, or as a solution or dispersion or suspension or melt.

The addition of the additive components to the polymer substrate can be carried out in customary mixing machines in which the polymer is melted and mixed with the additives. Suitable machines are known to those skilled in the art. They are predominantly mixers, kneaders and extruders. The process is preferably carried out in an extruder by introducing the additive during processing.

The additive components and optional further additives can also be added to the polymer in the form of a master batch ("concentrate") which contains the components in a concentration of, for example, about 2.0% to about 80.0% and preferably 5.0% to about 50.0% by weight incorporated in a polymer. The polymer is not necessarily of identical structure as the polymer to which the additives are added finally. In such operations, the polymer can be used in the form of powder, granules, solutions, and suspensions or in the form of lattices.

A preferred embodiment of the invention furthermore relates to a process for the production of an epoxy resin compos tion having flame retardant properties which com- prises mixing at least one polyfunctional ep-Oxide, the additive components and optionally further additives, solvents and a hardener component, optionally in the presence of a suitable accelerator, such as methylimidazole. Preferably, this composition is applied to a glass fibre fabric and dried to obtain non-sticky prepregs. These are further processed by stacking and pressing at elevated temperatures. The process is carried out in a known manner by analogous methods, such as the one de-'scribed in U.S. Patent Specification No. 5,084,546.

Incorporation can take place prior to or during the shaping operation. The materials containing the additives of the invention described herein preferably are used for the production of molded articles, for example injection molded or roto-molded articles, fibres, spun melt non-wovens, films, foams, resin transfer molding (RTM) and sheet molding compounds (SMC), bulk molding compounds (BMC), printed circuit boards, printed wiring boards, (pultruded) profiles, mono- and multilayer films, laminates, e.g. textile laminates, composites for planes, trains, coaches, automotive, ships, boats, construction, pipes, winded laminated (tanks), surface coatings and the like.

The following Examples illustrate the invention.

1 Materials

Diphenylphosphinyliminotriphenylphosphorane (I)

and

Diphenylthiophosphinyliminotriphenylphosphorane (II)

are prepared according to the methods as disclosed in U.S. Pat. Spec. 3, 189,564.

Epoxy resin: Araldite® ECN 1280 (o-cresol novolac epoxy resin, Huntsman Advanced Materials, Switzerland)

Epoxy resin: D.E.R.® 332 (Bisphenol-A epoxy resin, Dow Chemical Company, Switzerland)

Hardener: Durite® SD 1702 (phenol novolac, Momentive Specialty Chemicals, USA) Accelerator: 2-Methylimidazole (Sigma Aldrich, Germany)

Solvent: 1 -Methoxy-2-propanol (Merck Eurolab, Germany)

Aluminum trihydroxide (ATH): Martinal® OL 104 WE (Martinswerk, Germany)

Magnesium dihydroxide (MDH): Magnifin® H-5 (Martinswerk, Germany)

Boehmite (AOH): Apyral® AOH 30 (Nabaltec, Germany)

9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO): Ukanol® GK-F, (Schill+Seilacher AG, Germany)

Diethylphosphinic acid aluminum salt (DEPAL): Exolit® OP 930 (Clariant, Switzerland) Melamine polyphosphate (MPP): Melapur® 200 (BASF SE, Germany)

Melamine cyanurate (MC): Melapur® MC 15 (BASF SE, Germany)

Fyrol® PMP (PMP): oligomeric resorcinol methylphosphonate (ICL-IP, Israel)

3,3',5,5'-Tetrabromobisphenol A (TBBA, SigmaAldrich, Germany)

Melamine polyphosphate (MPP): Melapur® 200 (BASF SE, Germany)

Glass cloth: Type 7628 (P-D Interglas Technologies AG, Germany) 2 Test Methods

UL 94 test described in Flammability of Plastic Materials for Parts in Devices and Appliances, 5th edition, October 29, 1996.

Preparation of Epoxy-Glass Cloth Laminates

Stock formulations of ARALDITE ECN 1280 (85 wt.-%) and DURITE SD 1702 (50 wt.- %) in 1 -methoxy-2-propanol are prepared. To obtain the desired resin formulations, the appropriate quantity of the stock solution of ARALDITE ECN 1280 is mixed with 44.4 phr of the DURITE SD 1702 stock solution at 60°C for 30 min. Additional 1 -meth- oxy-2-propanol is added if necessary to adjust the viscosity of the formulation. 0.10 phr of 2-methylimidazole and the flame-retardant additives as specified in Table 1 are added and homogenized with the resin solution. The percentages of the flame retardant additives refer to the total resin composition including epoxy resin, hardener, accelerator and flame retardant components without considering solvents.

The formulation is hot coated onto a piece of glass cloth and heated to 170°C for about 1 .5-2.0 min in a forced draft oven. The fibre material, now a non-tacky prepreg, is cut into seven strips (~ 180 x 180 mm) which are stacked upon each other in a distance holder to assure the manufacture of laminates with uniform thickness of 1.6 mm. The strips are covered with two PTFE plates of 1 mm thickness on the upper and the lower side of the prepreg stack. The stack is placed on a hot press, and the stacked prepregs are subjected to a pressure of 3.0 bar at 190°C for a period of 2 h.

The resulting laminate is removed from the hot press, cooled to ambient temperature under 3.0 bar pressure, and separated from the distance holder and PTFE plates. The laminate is cut to a piece of about 150 x 150 mm by cutting off the edges with varying amounts of resin and weighed, its thickness measured, and the percentage amounts of its resin content determined. Test bars of the required dimensions are obtained by water jet cutting of the laminates.

3 Results

UL94 V (1.6 mm) test results obtained with epoxy laminates based on ARAL- DITE ECN 1280/DURITE SD 1702 (results of 5 test specimen each)

Table 1

*Ref.: Referential Example

The results presented above demonstrate that the inventive inventive resin compositions exhibit excellent flame retardant properties (UL94 V-0 classification). The inventive epoxy resin compositions give laminates with good laminate properties and excellent flame retardancy at relatively low levels of additives loading. 4 Additional Example

Example 13

Alternative preparation of laminates with the same composition as Example 4

A stock formulation of epoxy resin and I is prepared by dissolving 32.3 g ARALDITE ECN 1280 and 5.3 g I in 17.3 g 1 -methoxy-2-propanol at 90°C. Upon cooling to room temperature, I stays dissolved in the viscous clear solution.

This stock solution comprising ARALDITE ECN 1280 and I is mixed with 44.4 phr of a stock solution of DURITE SD 1702 (50%) at 60°C for 30 min. Additional 10 g of 1 -meth- oxy-2-propanol is added to adjust the viscosity of the formulation. 0.10 phr of 2-me- thylimidazole are added and homogenized with the resin solution. To this mixture, 28.0 g ATH are added and dispersed homogeneously.

The further procedure for the preparation of prepregs and laminates therefrom is as described above.

A laminate is obtained with a resin content of 50 wt.-%. Flammability testing according to UL94 results in a V-0 classification with a total burning time of 28 sec.

5 Test Methods

Preparation of Epoxy-Glass Cloth Laminates

D.E.R. 332 and DURITE SD 1702 are dissolved for 1 h at 90°C in 30.0 g 1 -methoxy-2- propanol. Additional 1 -methoxy-2-propanol is added if necessary to adjust the viscosity of the formulation. 0.10 phr of 2-methylimidazole and the flame-retardant additives as specified in Table 2 are added and homogenized with the resin solution. The percentages of the flame retardant additives refer to the total resin composition including epoxy resin, hardener, accelerator and flame retardant components without considering solvents.

The formulation is hot coated onto a piece of glass cloth and heated to 170°C for about 1 .5-2.0 min in a forced draft oven. The fibre material, now a non-tacky prepreg, is cut into seven strips (~ 180 x 180 mm) which are stacked upon each other in a distance holder to assure the manufacture of laminates with uniform thickness of 1 .6 mm. The strips are covered with two PTFE plates of 1 mm thickness on the upper and the lower side of the prepreg stack. The stack is placed on a hot press, and the stacked prepregs are subjected to a pressure of 3.0 bar at 190°C for a period of 2 h.

6 Results

UL94 V (1 .6 mm) test results obtained with epoxy laminates based on D.E.R.

332/Durite SD 1702 (results of 5 test specimen each)

Table 2

FR Additives Resin Total UL94 Ratcontent of Burning

Examples ing laminate Time

Component a) Component b) (1 .6 mm)

[wt.-%] [sec]

Example 14 9.5% I 35% ATH 50 41 V-0 The results presented above demonstrate that the inventive resin compositions exhibit excellent flame retardant properties (UL94 V-0 classification). The inventive epoxy resin compositions give laminates with good laminate properties and excellent flame re- tardancy at relatively low levels of additives loading.

7 Test Methods

Preparation of Epoxy-Glass Cloth Laminates

The test methods are carried out in a manner analogous to the ones described above (2 Test Methods)

8 Results

Table 3

^*Ref.: Referential Example The results presented above demonstrate that the inventive resin compositions exhibit excellent flame retardant properties (UL94 V-0 classification). The inventive epoxy resin compositions give laminates with good laminate properties and excellent flame re- tardancy at relatively low levels of additive loading.

Claims

1 .A composition which comprises a single component of

a) A phosphinyliminophosphorane of the formula

Wherein

R1-R5 independently of one another represent

X represents oxygen or sulphur; and

n represents zero or one; and

b) A polymer substrate based on polyfunctional epoxides and, optionally, hardener compounds, with the proviso that combinations of polyfunctional epoxide compounds and hardener compounds that contain at least two aliphatic amino groups are excluded.

2. A composition according to claim 1 , which comprises a single component of a) A phosphinyliminophosphorane (I), wherein R1-R5 independently of one another represent Ci-C₄-alkyl or phenyl, X represents oxygen or sulphur and n represents one.

3. A composition according to claim 1 , which comprises a single component of a) A phosphinyliminophosphorane (I), wherein R1-R5 independently of one another represent phenyl, X represents oxygen and n represents one.

4. A composition according to claim 1 , which comprises as component b) at least one polyfunctional epoxide compound, wherein at least two epoxy groups of the partial formula

are present, which are attached directly to carbon, oxygen, nitrogen or sulphur atoms, and wherein q represents zero, Ri and R₃ both represent hydrogen and R₂ represents hydrogen or methyl; or wherein q represents zero or 1 , R-i and R₃ together form the -CH₂-CH₂- or -CH2-CH2-CH2- groups and R₂ represents hydrogen.

5. A composition according to claim 1 , which comprises as optional component ad- ditives selected from the group consisting of tetraalkylpiperidine additives, polymer stabilizers, fillers, reinforcing agents and so-called anti-dripping agents that reduce the melt flow of thermoplastic polymers and reduce the formation of drops at higher temperatures.

6. A composition which comprises

a) A combination of a phosphinyliminophosphorane of the formula

Wherein

R1-R5 independently of one another represent

CrC₄-alkyl, C₆-Ci2aryl, (Ci-C₄alkyl)_{1 -3}C6-Ci2aryl or

(Ci-C₄alkoxy)i-₃C6-Ci2aryl;

X represents oxygen or sulphur; and

n represents zero or one;

with at least one additional flame retardant; and

b) A polymer substrate based on polyfunctional epoxides and, optionally, hard- ener compounds.

7. A composition according to claim 6, which comprises a) a combination of a phosphinyliminophosphorane (I), wherein R1-R5 independently of one another represent Ci-C₄-alkyl or phenyl, X represents oxygen or sulphur and n represents one; with at least one additional flame retardant selected from the group con- sisting of phosphorus containing flame retardants, nitrogen containing flame re- tardants, nitrogen and phosphorus containing flame retardants, organohalogen containing flame retardants and inorganic flame retardants.

8. A composition according to claim 7, which comprises a) a combination of a phosphinyliminophosphorane (I), wherein R1-R5 independently of one another repre- sent phenyl, X represents oxygen and n represents one; with at least one additional flame retardant selected from the group consisting of phosphorus containing flame retardants, nitrogen containing flame retardants, nitrogen and phosphorus containing flame retardants, organohalogen containing flame retardants and inorganic flame retardants.

9. A composition according to claim 8, which comprises a) a combination of a phos- phinyliminophosphorane (I), wherein Ri-R₅ independently of one another represent phenyl, X represents oxygen and n represents one; with at least one additional flame retardant selected from the group consisting of

Phosphorus containing flame retardant selected from the group consisting of tetra(2,6-dimethylphenyl)resorcinol diphosphate, oligomeric resorcinol methyl- phosphonate, salts of di-CrC₄alkylphosphinic acid, salts of hypophosphoric acid and 9,10-dihydro-9-oxa-10-phosphorylphenanthrene-10-oxide (DOPO) and its derivatives;

Nitrogen and phosphorus containing flame retardant selected from the group consisting of melamine polyphosphate, ammonium polyphosphate, melamine ammonium phosphate, melamine ammonium polyphosphate, melamine ammo- nium pyrophosphate, a condensation product of melamine with phosphoric acid and other reaction products of melamine with phosphoric acid and mixtures thereof;

Organohalogen containing flame retardant selected from the group consisting of polybrominated diphenyl oxide, decabromodiphenyl oxide, tris[3-bromo-2,2- bis(bromomethyl)propyl]phosphate, tris(2,3-dibromopropyl)phosphate, tris(2,3- dichloropropyl)phosphate, tetrabromophthalic acid, tetrabromobisphenol A and bis(2,3-dibromopropyl ether); and Inorganic flame retardants selected from the group consisting of aluminium tri- hydroxide (ATH), boehmite (AIOOH), magnesium dihydroxide (MDH), hydrotal- cite, zinc borates, CaC0₃, (organically modified) layered silicates and (organically modified) layered double hydroxides, polyhedral oligomeric silsesquiox- anes, and mixtures thereof.

10. A process for imparting flame retardancy to a polymer substrate, which comprises adding to polyfunctional epoxides and, optionally hardener compounds as the flame retardant the phosphinyliminophosphorane of the formula

Wherein

R₁-R5 independently of one another represent

CrC₄-alkyl, C₆-Ci₂aryl, (Ci-C₄alkyl)_{1 -3}C6-Ci₂aryl, or

(Ci-C₄alkoxy)i-₃C6-Ci₂aryl;

X represents oxygen or sulphur; and

n represents zero or one; as single component;, and

with the proviso that combinations of polyfunctional epoxide compounds and hardener compounds that contain at least two amino groups are excluded. A process for imparting flame retardancy to a polymer substrate, which comprises adding to polyfunctional epoxides and, optionally hardener compounds a combination of a phosphinyliminophosphorane of the formula

Wherein

R₁-R5 independently of one another represent

Ci-C₄-alkyl, C6-Ci₂aryl,(Ci-C₄alkyl)_{1 -3}C6-Ci₂aryl

(Ci-C₄alkoxy)i-₃C6-Ci₂aryl;

X represents oxygen or sulphur; and

n represents zero or one;

with at least one additional flame retardant.