CA2213328A1 - Plasma deposited film networks - Google Patents

Abstract

A three-dimensional functional film network comprising a plurality of radio frequency discharge plasma film layers. The plasma film layers include a first layer, comprising a plurality of a first functional group, and a second layer, comprising a plurality of a second functional group. The employment of threedimensional film networks with desired functional groups located either on the periphery or both the periphery and interstitial spaces of the networks significantly increases the surface functional density.

Description

CA 022l3328 l997-08-l9 W O 97/22631 PCTrUS96/20267 PLASMA DEPOSlTED FILM NETWOI~KS

,~ BACKGROUND OF T~, INVENTION

S Field of me Tnvention The present invention relates to functional film n~;lwul~, and in particular to sequentially deposited radio frequency plasma film layers ha*ng an open network structure, thereby h-c-ea~mg ;"~ spacing b~Lwt;c;ll plasma film layers and providing access to functional groups cont~in~d therein.
10 Previous ~
The sllrf~res of polymeric, metal and c~r~miC m~teri~le are important in many applications. Often these sllrf~-~ee must be modified for a specific use. For eY~mrle, snrf~rçs of m~lir~l devices impl~ntetl in the body must have bioc-.,..l.h~ihle ~.~, r~ces Dirr~l~.ll methods are pen~r~lly employed to modify the sllrf~cçs of polymers, 15 as opposed to metal and c~r~mic ~", r~ces. Several Cullvt;l ,1 ion~l methods of surface modification employ wet chemical processes. Most rectil~lly developed are energetic methods of surface modification. Each of these methods for each type of m~t.ori~l is fliicneeecl below.
Wet chemical surface mntlific~ti~m of metals and c~r~mi~s is acc~ mplieh.orl 20 either by forming composites where the metals and ceramics are blended with matrix resin, or by coating these substances with organic co~tin~s A typical wet ~h~miczll ayyloach of surface modification of polymeric m~t~ri~l~ employs acids to etch and oxidize the s-lrf~re Other approaches employsolvent swelling and yellc~dLion of topical co~tin~ into the swollen ~ulrdce~. Upon 2~ ~v~uldlion of the solvent, the coating is incolyoldl~d into the top layer of the polymeric article.
There are many problems associated with use of solvents and other wet chemical m~th~ for modifying sllrf~r~ For example, the use of wet chemi~l methods to modify sllrf~res can take several steps to acc- mpli~h The çhemir~l~ used are often messy, corrosive and toxic to both hllm~nc and the en~dl.~.. ~.,l There are CA 022l3328 l997-08-l9 methods to modify surfaces can take several steps to accomplish. The ~~hPmic~l~ used are often messy, c...-usivc and toxic to both hllmAn~ and the cllvholllllcnl. There are often many steps, such as the application reaction, rinsing, and ne~ltrAli7Atic n It is not easy to change steps if sequentially applying several chemicals. Not all surface areas 5 of the mAteriAl to be modified are ~cc~ihle to the wet ch~mic~ls, such as blind vias and other hidden sllrf~ces The monomers used must be reactive. Yields are low and solvents can leave residues on the surface leading to co~ tit~n of the surface.
~Mi~innAlly, some wet chemic~l methods can also damage the surface that one is ~lclll~lh~g to modify.
Surface co,ll~osilion of polymeric m~t~r1Al~ is comm- nly modified by blending additives into the bulk polymer before fabrication and allowing surfaceactive agents to migrate to the surface. The end groups of the polymer chain can also be modified with specific functional groups. Changes to tbe bulk of the polymer are thus ., ~ ,c~1 The added mobility of the end groups relative to the polymer backbone appear to fiA-~ilit~te self-assembly of the molecular overlayers by the surface active end blocks.
A major drawback of this method of surface modification is that there is a limit to the chemical fi-nc~ti~n~l density that can be incoll,o~aLcd without significantly Altering the basic nature of the mAt~riAl Energetic processes (i. e., plasma) for surface modification of polymeric mAteri~ls have also been gaining acceptance in a number of in-ln~tries In plasmamo-lific~AtiQn, the bulk ~3l~cl~ies of the original polymer are retained while chemically ~hAnging only the top 20 A of the snrf~e Polymers such as polyl.lo~ylene, poly~Lyl~,ne, polyester, TeflonE9 and other commercially available polymers have been modified using this method. For example, a poly~Lylcne m~t~riAl that nc)rm~lly does not contain nitrogen can be modified using Amm~1ni~ gas ionized in a radio frequency (RF) field. This method commonly employs a vacuum chamber, means for introducing a reactive gas such as oxygen, ammonia or nitrous oxide into the chamber and RF energy as tools in the modification process.

W O 97/22631 PCTrUS96t20267 In plasma surface modification, the gas employed for modifying the surface of the polymer is introduced into the vacuum chamber coi~ i..g the surface to be modified. The gas is ionized using RF energy and this ionized gas i~ with the surface of the m~teri:~l Ionized gases contain a l~ lulc of highly reactive chemical 5 species that include free radicals, electrons, ions and metastable reactive species.
These species easily break the ~h~rnic~l bonds on the surface of polymeric m~t~ri~le and ~ L..le the desired chemical groups on the surface ofthe m~t~-.ri~ql In thismanner carbonyl, carboxylic acid, hydroxy, and amine functional groups have beenincolpuldl~d into and hence become a part of polymeric s~lrf~c~es.
The design of the reaction chamber, the distribution of power, the excitation frequency, and the gas dynamics are critical factors influencing the plope,lies and efficiency of plasma reactions. Extensive work has been published that shows a direct correlation bc;lv~ excitation frequency and plasma reactivity.
Unlike polymeric m~tf~ri~le, metals and ceramics do not contain bonds that can be easily broken. Plasma film deposition offers a means for modifying the surfaces of such m~ In this process monomers con.eieting of polyatomic molecules are typically ionized using RF energy.
Using plasma polymeri7~til3n (or plasma film deposition), functional groups can be incorporated into or deposited on any surface, including polymers, metals, ceramics and composites. The films deposited using plasma polymerization are compositionally very di~'~ from the polymers formed in bulk processes of polymeric m~teri~lc using these same monomers. ~tçri~l.e such as methane, propane, and other s~Lul~ d hydrocarbons are commonly employed to deposit plasmapolyll,c~i~;d films on metals and ceramics. Additionally, the film can be comrri~e~l of ~mines, acids, methacrylates, glycidyls or mixtures such as methane and amine, or methane and acid.
When depositing functional fflms on surfaces using plasma film deposition, the functional density in most cases is limited to that achieved by a monolayer. For exsmple, 11 atom % nitrogen in films deposited from ~ minl~cycloh~x~ne on poly~ly~ e was reported in Clinical Materials 11 (1992). This concentration equates W O 97/22631 PCTrUS96/20267 to a cl)nrentr~tion of i nmoles/cm2 of ~lhll~ y amines on the surface or a coverage of one monolayer of amine on the surface.
The difficulty with most single monolayers of functional density is that there are a limited number of ch~miç~lly reactive sites that are available for interaction with S the desired coating m~t~ri~l such as a biomolecule or the matrix resin of a composite When the number of functional groups available on the surface of a ~u1,sl~ is limited, the benefits that can be achieved are also limited. In the case of composites, the number of locations where the matrix resin is bonded to the lei~ cil~g m~t~ri~l~
is limited and the nltim~te strength of the composite m~t-ri~l is also limite~l In the 10 case of biomolecule ~ el~ ent, lower functional densities decrease the amount of these materials that can be anchored on the surface. Often ~tt~rhment of more than one biomolecule is desired to f:~rilit~te m1l1tip]e ~ ce attributes. In these cases the amount of any given m~tPri~l that can be ~tt~rh~cl is decreased and may be below the lllh~ unl threshold needed for the desired performance.
lS Plasma polymeri7~1 films have also been deposited using acrylic acid which produces films with a high density of functional groups. The density is achieved by building a linear polymer of acrylic acid on the snrf~re Additionally, soft plasma or pulse plasma has been employed with variable duty cycle to preserve the functional groups of films during deposition using plasma polymeri7~tion. In addition to only 20 leaving a single monomer layer deposited, these methods also depend on building long linear chains anchored to the surface to generate the high functional densities that are desired.
Further, in plasma deposition, the energy per mole of monomer d~L~ es the number of bonds broken. At high power and low monomer conc~;llLldLion (hard 25 plasma) more of the bonds are broken and less of the functional character is retained.
It is known that the power applied, the frequency of the pulse, and the duty cycle can all be varied to preserve the functional nature of the deposited filrn. Indeed, it has been found that by using high power coupled with a low duty cycle, a higher portion of the functional nature of the deposited film is m~int~ine-l A major 30 drawback of these methods is that the films that are deposited are mç~h~nically weak W O 97/22631 PCT~US96/20267 and can be easily abraded away. Furthermore, during plasma film deposition, there are two colllpdillg processes that occur. One is the deposition of the film and the ' other is the ablation of the film being deposited. The degree to which one process predo. ~ es is a function of both the process conditions being employed and the chemical nature of the film being deposited. In an attempt to build sufficient functional density on the surface using plasma polymeri7~tion, there is also an inherent risk that some of the film being deposited will be ablated away due to the process conditions that need to be employed.
~ven if sufficiently long chains of reactive groups could be deposited, the 0 groups at the lower regions of the film may not be as easily ?cces~ihle for interactions with coating m~teri~l~ as is desired. For ç~mple7 in films deposited from allylamine, it has been found that a ~lilll~y amine concentration on the surface is not as high as would be expected from the nitrogen content of the surface measured by ES~A. It has been conrl~ e~1 that perhaps some of these functional groups were buried and not ~ccessihle on the surface for reaction with the derivatizing reagents used in their analysis.
Finally, star polymers have been created employing wet chernical methods.
For example, the synthesis of star polymers have been reported after reacting multifilncti~ n~l isocyanates with glycols.
In U. S. Patent Nos. 4,507,466; 4,588,120; 4,568,737; 4,587,329; and 4,694,064, herein incorporated by reference, Tomalia, et al. disclose synthesis of giant star polymers c( mmonly referred to as ''tlPnl1rim~o.rc''. In the noted patents, sequential reactions of methylacrylate and ethylene~ mine are achieved employing methanol as a solvent. Star polymers offer several advantages, namely, a network structure that provides physical stren~th and the ability to provide high chemical fimctional densities.
There are several problems associated with star polymers. First, the conventional method of building molecules from the core produces only small cluantities of star polymers and requires several days to accnmpli~h Second, large scale synthetic methods remain to be developed.

W 097n2631 PCTAUS96/20267 Additionally, in order for star polymers (and ~ nc1rimerc) to be useful in modifying s-lrf~res of m~t~ri~ls, star polymers must be anchored to reactive sites on sllrf~ces using reactive cores as ~1t~rhment points. This type of ~nchnring has many problems. For example, it is difficult to attach ~ntlrimers to surfaces because the S ~n~h~-rin~ point of the core is located in the center of the star. Thus, ~n~hr~rin~J can only occur through a reactive group on the periphery of the dendrimer. Even in these cases the substrate to which the ~len-lrim~r is attached must be modified by some means to allow ~tt~hment Steric hinflr~nce of the star also limits the amount of ~len(lrimer.c that can be 10 ~tt~che-l to a surface. Additionally, it is easy to break this single ~tf~chment.
In biomedical applications, for e~mple, a stent or other object placed in the body, the medical devices must have the biomedically active agent fixed to and completely cover the surface. Dendrimers provide space between each ~tt~rhment, leaving substrate surface areas exposed to body fluids.
Most plasma procescing techniques employ the deposition of functional groups on the surface as the end point of their process rather than as an int~rme~ t~
link in an ultimate structure. Therefore, practitioners employ conventional m~teri~
such as oxygen, ammonia and other such m~tPri~l~ to deposit functional groups on the surface. For example, in U.S. Patent No. 5,342,693, herein incorporated by ler~ .ce, 20 a glassy film is deposited using siloxanes ionized in a plasma. Using the methods of plasma surface modification, ammonia is then used to provide amine functional groups on the surface. Other m~terizll~ are subsequently attached to this functional group using wet chemical methods.
Therefore, what is needed is (i) a sequentially deposited film network 25 comprising several RF plasma layers and having a strong interface, (ii) a method to provide high functional density film n~Lw-,lh~ with controllable amounts of cro.cclinkin~ for accessible functional groups, and (iii) means for providing large scale RF plasma deposition that can be accomplished in a relatively short time without employing wet chemical methods.

W O 97~2631 PCTAJS96/20267 SUMMARY OF THE I~VENTION
The present invention ~ul~L~llially reduces or overcomes all of the problems associated with the prior art. The invention provides a novel three--lim~n~ionalfunctional film network and a rapid process for producing same. The employment of S three flimen~onal film n~Lwc~ with the desired filn~ti-)n~l groups located either on the periphery or both the periphery and illlel~Lilial spaces of the networks of the invention offers a means for significantly increasing the surface functional density in a novel manner. The spatial configuration of the network, and thereby access to the internal structure of the network, is controlled by selecting which functional groups 10 are sequentially deposited. The novel process of the invention employs sequential radio frequency (RF) deposition, thereby allowing for large scale synthesis.
Additionally, no wet chemi~ry is employed, thereby decreasing production time from days to ...;..."~c The present invention provides a "forest" or a "lnu~l~oom" with many 15 functional groups on the periphery. The approach has not been previously achieved using plasma deposition and it is not readily obvious or feasible.
In the present invention, sequential deposition is coupled with an infinite variation in the type and functionality of the monomers employed to ~L~I ., . i "e the ~lltim~te structure of the film that is deposited. These variables are employed in 20 addition to the variation of process conditions to control film structure.
Accordingly, it is an object of this invention to provide a functional film network c~ ., l .p, ;~ a plurality of sequentially deposited RF plasma layers.
It is also an object of this invention to provide high functional density film networks with controllable amounts of cro,sslinkin~ and hlLel~lilial spacing, providing 25 access to the functional groups cont~ine~l therein.
It is also an object of this invention to provide means for large scale depositions that can be accomplished in a relatively short time.
In accordance with the above objects and those that will be mentioned and will become a~ below, the three-~1im~n~ional functional film network in accordance 30 with this invention compri~es a plurality of radio frequency discharge plasma film W O 97/22631 PCT~US9~/20267 layers. The plasma film layers include a first layer and a second layer disposedimmerli~tely ~ cent said first layer. The first layer includes a plurality of a first functional group and the second layer inchl~les a plurality of a second functional r group.
S An advantage to this invention is that it provides a film net~vork structure having increased i~ l spiqcing with reactive fimctinn~l groups disposed within the network structure. These reactive sites may act as ionic binding sites for securing biomolecules within the n~lw~,hs.

PETAILI~:D DESCRIPTIQN OF THE ~ TION
The plasma polymeri7~tion technique of the present invention offers a unique method for building functional network structures. In general, a layer of one class of monomers is ~h~ te~l with a layer of another class of monomers.
The specific monomer selected depends on the type of functional surface that is desired. In some cases, a lllixlule of gases is employed to obtain the desired surface ~ h~ try.
The class of monomers selected dictate the type and density of the network that is developed. Examples of functional groups that can be inc~ L~d in the network structure of the present invention include, but are not limited to, epoxy (o~ yl), amino, carboxy, hydroxy, isocyanto, amido and sul~ydryl groups.
Monomers sources of epoxy or ~ yl functional groups include, but are not limited to, allyl glycidyl ether, glycidyl meth~crylate~ glycidyl isopropylether, glycidyl butyrate, 3-glycido~y~lopyll.. ethoxysilane and ll~ s thereof.
Monomer sources of alcohol functional groups include, but are not limited to oxygen; water; ~alul~ed alcohols such as methyl alcohol, ethyl alcohol, propyl 25 alcohol and its isomers, butyl alcohols and its isomers and saturated alcohols and aryl alcohols such as benzyl alcohol; unsaturated alcohols such as allyl alcohol, vinyl alcohol, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate and other similar compounds; glycols and ethers such as ethylene glycol, propylene glycol, tetrahydrofuran, diethylene glycol dimethyl ether, tetraethylene glycol dimethacrylate CA 022l3328 l997-08-l9 and triethylene glycol dimethyl ether; mixtures of the above compounds; and lllixLul~s of a hydrocarbon such as methane or ethylene and the classes of compounds named herein.
Monomer sources of isocyanate functional groups include, but are not limited S to, allyl isocyanate, toluene-2,4-diisocyanate, 1,4-diisocyanatobutane, ethyl isocy~l~le, he~r~met~ylene diisocyanate, toluene-2,6-diisocyanate and lllixlul~es thereof.
Monomer sources of triazine functional groups include, but are not limited to, acrylonitrile, 2,4~ minn-6-methyl-1,3,5-tri~7in~ trimethylsilyl-1,2,4-triazole and 10 lllixLules thereof.
Monomer sources for amine functional groups include, but are not limited to, lme~ rz~terl amines such as allylarnine and vinyl amine; p..,l~aly amines such as methylamine, butyl amine, propylamine, hydroxyethyl amine and other alkyl ~min~s;
alkane diamines such as ethylene~ min~, 1,3 ~i~min~r~e, 1,4 ~ mino butane, 1,5 ~ mino pentane, 1,6 tli~min~ hexane, 1,7 ~ min~ heptane, 1,8 ~ mino octane;
polyalkylene polyamines such as diethylenetri~mine, dipl~o~?ylene tri~mine"
dibutylenetriSlmin~?7 triethylenel~lldlllille, (~ ylelle~ ine, tributylen~
N, N'-bis(2-arninoethyl)-1,3-prop~ne/li~min~, bis(3-aminopropyl)amine, aminosilanes such as 3-Amino~lu~ylllhnethoxysilane, 3-Amino~l~yllliethoxysilane~
20 3-Amino~ yh--ethyldiethoxysilane, 3-(3-Aminophenoxy)propyltrimethoxysilane, 3-(2-Aminoethylamino)~ro~yl~lilllethoxysilane, h~methyl~ 7~ne, and other similar compounds, heterocyclic amines such as ethylene amine, piperillin~, pyrroles and pyrrolidines; aromatic amines such as aniline; and various other amines and amino compounds such as mercaptoethylamine, acrylonitrile, acetonitrile, 25 butyronitrile, and 1,4 diaminocyclohexane; llli~ s of the above compounds; and mixtures of a hydrocarbon such as methane or ethylene and the classes of amino compounds named herein.
Monomer sources for carboxylic acid functional groups include, but are not limited to, oxygen, carbon dioxide and compounds such as acetic acid, propionic acid, 30 butyric acid, 2-methyl propionic acid, n-pentanoic acid, 4-methyl butanoic acid, g WO 97/22631 PCT~US96/20267 n-hexanoic acid; u~ at~d acids such as acrylic acid, methacrylic acid, 2-butenoic acid, and ~ iC acid; nli2~ cs of the above; and ~ c;S of a hydrocarbon such as methane or ethylene and the classes of compounds named herein.
Monomer sources for sulfhydryl groups inch~rle, but are not limited to, compounds such as 3-sumlydl yl propene, hydrogen sulfide, 2-sulfhydrylethene andmixtures thereof.
Monomer sources for amido functional groups include compounds such as acrylamide and N,N-dimethylacetylamide. Additionally, amido groups can be formedby neutralizing tr. ., .il~l amine with an acid or a tt~rmin~l carboxylic acid function with an amine.
Other monomer types that can be used in constructing the network structure irrespective of their ability to contribute a functional group within or on the periphery of the network ~ll .u;lult: include, but are not limited to, compounds such as allyl acetate, allyl methacrylate, ethyl acrylate, methyl acrylate, methyl methacrylate, ethyl methacrylate, butyl acrylate, tert-butyl acrylate, butyl methacrylate, cyclohexlmPth~rrylate, ethylhexl acrylate, 2-ethylhexyl methacrylate. If multifunctional acrylates such as ethylene glycol dimethacrylate are used, these monomers will provide additional sources of br~nchin~ besides the amines.
Although specific compounds that can be used to form the desired functional groups in the network of the present invention have been named, it is to be understood that any m~tf~ that can be inkoduced in an RF plasma reaction charnber, either as a vapor or an aerosol mist, that can be subsequently ionized by the appli~ti on of RF
energy, and that belong to the family of compounds named herein, are ~e-;livt;
sources of such functional groups.
Table I lists reactive monf)m~r pairs that can be employed within the scope of this invention to initiate the e~t~n~ed chains of the functional film networks. For example, a plasma film layer having a functional group selected from the first column will build a new layer in the film network if reacted with a plasma film layer having its functional group pair in the second column. In reaction No. 1, a previous layer --lo---CA 02213328 1997-08-l9 WO 97/22631 PCTrUS96/20267 having amine is reacted with monomers that will deposit ethylene functional groups, producing two network branches in the new layer of the network.
TABLE I
Reactive Pairs that Initiate Fxt~n~e~l Chains Surface or Reacts To Chain-End Function With Produce 1. -NH2 CH2=CHX N<CH2CH2X

2. -NH2 o=c~RRz -N=C<R2 3. -COOH NH2R -CONHR

4. -COOH NHRI ~R
\R2 5. -COOH NH2(CH2)nNH2 -CONH(CH2)nNH2 6. -COOR NH2R -CONHR

7. -COOR NHRl -CO-~-R
\R2 R2 8. -COOR NH2(CH2)nNH2 -CONH(CH2)nNH2 9. -CHO NH2R -CH=NR

10. -NCO NH3 -NHCONH2 11. -NCO NH2R -NHCONHR

12. -NCO NHRl -NHCO-N-R
\R2 \R2 13. O\ RNH2 ~OH
-(~----CH2 -CH--CH2NHR

14. O\ NHRI ~OH
~----CH2 \R2 -CH--CH2NR

CA 02213328 1997-08-l9 15. 0~ ROH C~OH
-C~----CH2 - H--CH20R

16. ,N~ NHRl ~NH2 -~H----(~H2 \R2 - H--CH2~NR~

17. ~N~ ROH ~H2 -~H~ H2 - H--CH20R
1 8.-OH
~ ~2--- HR
19. -OH RSO2Cl -OSO2R
20. -N-C~

21 .-SH

wherein X is -COOH, -COOR, -OH, -NH2, -NH2R, -NCO, -C~-~H2 -~N~H2 ~2 and R, Rl and R2 represent aliphatic or aromatic hydrocarbons that can be introduced in an RF plasma reaction chamber, either as a vapor or an aerosol mist that can be subsequently ionized by the application of RF energy.
Additionally, the R, Rl and R2 groups may contain additional functional groups to allow further ~
The reaction ill.. ;l ~ ~t~l in line 5 of Table 1 changes a t~nn;n~l -COOH group to a t~rrnin~l -NH2 group, with a variable chain extension length (n). Reaction No. 8 changes a t~rmin7~1 - COOR group to a t~--rrnin~l -NH2 group, with a variable chain t~tf~n~ion length (n). The reaction of line 19 is employed as a wet ch~1nic~l step prior to ~ffixing biom~t~ri~l. In reaction No. 20, the triazine source is acrylonitrile.

W O 97/22631 PCTrUS96/20267 According to a plc;rell~ d embodiment of the invention, the construction of the film network occurs as follows: an initial plasma polym~.ri7.~1 film layer is first deposited on the substrate. This initial layer ean be chosen from the class of compounds such as ammonia, unsaturated ~min~s, ~lh~ min~s, aliphatic 5 ~ min~s, polyaLkylene poly~mines, heterocyclic ~min~s, nitriles, pyrroles, pyrrolidines, aminosilanes and ~ lw~s thereof such that an amine funetional group is formed on the surface. The initial layer may also C~ m~e oxygen, water, carbon dioxide, and mixtures of a hydrocarbon and the above referenced compounds. The second plasma deposited layer is applied using the class of compounds con~ fin~ of, 10 (i) saturated carboxy}ic acids such as acetic acid, propionic aeid, butyric aeid, 2-methyl propionic acid, n-pentanoie acid, 4-methyl butanoic acid, n-hexanoic acid, and unsdluldl~;d carboxylic acids such as acrylic acid, methacrylic acid and similar unsaturated acids; or (ii) esters such as methyl acrylate, methylm~ th~crylate, glycidyl methacrylate and similar elass of compounds, or (iii) keto esters such as carbonyl-bis-15 3,3 '-methyl propionate and similar compounds; or (iv) oxygen and carbon dioxide (v) llli~lw~s of hydrocarbons and the class of compounds named in groups (i) through (iv). The second layer can also be constructed by using monomers that consist of a mi~lul~ of compounds chosen from groups (i) and (ii). Of the three classes of compounds mentioned, it is ~ler~ d that the monomer for the second layer 20 be chosen from the class of compounds described in groups (i) and (ii).
The plasma deposited film network can also be initi~te~l by depositing a film using the monomers from the class of compounds e- n.ci~ting of; (i) .~ e~l carboxylic acids such as acetic acid, propionic acid, butyric acid, 2-methyl propionic acid, n-pentanoic acid, 4-methyl butanoic acid, n-hexanoic acid, and lm~ r,qtecl25 carboxylic acids such as acrylic acid, methacrylic acid, and other similar m~teri~l~, or (ii) esters such as methyl acrylate, methyl methacrylate, glycidyl methacrylate and other similar m~t~ri~l~; or (iii) oxygen and carbon dioxide; or (iv) ~ lwes of hydrocarbons and the class of compounds named in groups (i) through (iii). This first layer can also be formed from a llliXlw~ of monomers described in groups (i), (ii) and 30 (iv) or the mi~Lulc;s described in group (v). The second layer of plasma polymerized W 097/22631 PCT~US96/20267 film is then deposited from the group cnn~ ng arnmonia, unsaturated amines, min~s, z lirh~tio ~ mines, polyalkylene poly~llLles, heterocyclic ~min os, nitriles, pyrroles, pyrroli~lin~, aminosilanes and ~ lw~s thereof or ~ s of hydrocarbons and the class of amino compounds named herein, as described above.
S Employing one combination of mslteri~ as an example, Steps 1-5 below str~te the step by step growth of the functional film network on poly~yl~,e according to the invention. The process also illustrates how the overall networkstructure is achieved. The sequential deposition process allows for evaluation of the filn- tion~l chd-a ;Lel at each step. The employment of difunctional amines such as ethylene ~ min~ (See Formula 1~ or 1,6 he~r~ne~ mine with allylic or aliphatic acids, such as acrylic acid, will yield a network according to final Steps 4 and 5, as illustrated in Form~ 7 and 8 below.
The objective of Step 1 below, is to provide a set of IC:a iLiv~; sites for br~n~hin~ Any monomer from the first column of Table I can be employed in the first step. In the method showvn, an amine having an R group is plasma polymeri7f ~1, producing many amine functional groups on the polymeric surface for the next level of br~n~hing The R group of the amine is generally broken, leaving Rl and R2 groups as part of the functional groups attached to the surface, or left lm~ff~c he~l in the reaction ch~mher.

+ NH RNH Plasma Fo~ 'ormula 2 In Step 2 below, a m~t~hing pair is selected from the second column of Table I. During plasma deposition the m~tchinF pair will now attach to an amine functional group previously ~ che~l to the surface during Step 1. In Step 2 below, an acryIic W O 97/22631 PCTAUS96nO267 acid is shown. The two hydrogen bonds on each amine are easily broken. The process can be adjusted so that there is more than one carboxylic acid deposited. For example, if pulse plasma is employed as illustrated in Step 2 below, two carboxylic acid units will attach at the nitrogen, creating two branches.

Plasma --RINH2 + 2CH2=CHCOOH

Formula 2 Formula 3 /~R2~oH
~ \R2 1 1 OH

Formula 4 The purpose of Step 3 is to provide another point for br~nchin~ For example, 20 as illustrated below, an ethylene ~7i~nninP plasma is again employed. Reacting these amines with the carboxylic acid functional groups deposited in Step 2 provides amides. At the other end of each amide is an amine which provides another - opportunitv to provide two branches.

W O 97/22G31 PCTrUS96nO267 .~
~RlN~-~ 2+ 2NH2RNH2 Plasma ~ 'R2C~OH

Formula 4Formula 1 ~ R2~NHRlNH2 '- -RIN-/
"'R2~NHRINH2 Formula 5 Steps 1-3 provide the first generation of the film network. This first layer hasa strong int~rf~ce with the surface, as opposed to other networks formed from long, linear branches and star polymers being ~tf~c~herl at the cores to a surface. The strong inf~-rf~re of the present invention covers all of the surface and is not ablated during additional layer depositions. Additionally, there is no problem of steric hindrance when ~tt~rllin~ additional functional groups.
When using the monomers illustrated in Steps 1-3, the surface layer will have many functional ~mines Br~nchinp is not accomplished when amines are deposited.
However, when carboxylic acids are deposited onto amine functional groups, br~nching is possible.
As illustrated in Steps 4 and 5 below, the sequential deposition method of the invention is employed to produce a second generation film network. In Step 4, the W O 97/22631 PCTrUS96/20267 two hydrogen bonds on each amine are again easily broken, as previously shown inStep 2. The process can be adjusted so that there is more than one carboxylic acid deposited. For example, if pulse plasma is employed as ill~ ed in Step 4 below, two more carboxylic acid units will attach at the nitrogen, providing four branches for S each amine fimctional group attached to the surface.

~TEP4 ,R2CNHR NH
0 ~ --RIN'~ I 2 + 4CH2=CHCOOH Plasma "'R2 ICNHRINH2 Formula ~ Formula 3 ~ "-R2C~O~I
,R2~NHRlN--' R2CI OH
,~' O
--Rl~ O!
'R2lclNHRlN~ ~R2COH

Formula 6 W O 97n2631 PCTAJS96/20267 STEP~

" R2COH
,R2CNHRIN''- R2COH
RIN\ + 4NH2RNHz Plasma 2~ N<R2C~H

Formula 6 Formula 1 1~ 0 ~ jR2cNHRlNH2 ~/R2cNHRlN~R2~NHRlNH2 --Rl~ O

'R2CNHRIN-'R2~NHRINH2 1~ R2bNHRINH2 }S
Formula 7 The process of sequential deposition can be continued through several iterations until the desired final network structure is achieved. The process is termin~t~d only when the desired thickness of the film network has been deposited on 20 the ~ dl~ of choice and the target chemical functional group density has been incoll,urdl~d into the network.
A s~ucture beginning with a lliru~ Lional amine on the surface is illuskated below in F~ nnl~e 8-11. By using a tetr~fi-n~ n~l functional monomer such as triethylenf !e~ P., NH2CH2CH2NHCH2--CH2NHCH2CH2NH2, cleavage ofthe -~8-CA 022l3328 l997-08-l9 W O 97/22631 PCT~US96/20267 molecule can occur in a plasma at the location shown by the dotted line. In a manner analogous to deposition from a .~ c, and as shown below, a surface with three hme~nl~ points can be obtained, one at the seconda~y amine and two at the p~ ~y amine site.

--RIN--RINH2 + 3CH2=CHCOOH Plasma Formula 8 Formula 3 OH
C-O
R2 ,R2COH 3NH ~ Plasma RIN Rl~R2COH 2 2 Formula 9 Formula 1 ,R2CNHRINH2 ~~ Plasma RIN--RIN ~' + 6CH2--CHCOOH
~ ''R2lcNHRlNH2 Formula 10 Formula 3 W O 97~22631 PCT~US96nO267 O

1~ ~R2~0H
R2CNHRIN ' ---R2C~OH

,R2CNHRIN~K2 S ~ RIN--RIN~ CoOHo '\. "R2l~0H
\R (~NHR N

Formula 11 A structure with linear amine chain as the starting group is shown in Form 12-15 below. When a monomer such as allylamine is employed as the starting monomer, a pulse plasma can be employed to build a linear chain c- n~i~ting of several amine groups, each of which can act as a branch site.

NH2 NH2 NHz Plasma NH2 + 8CH2=CHCOOH

Formula 12 Fo. lq 3 CA 022l3328 l997-08-l9 W O 97/22631 PCT~US96/20267 OH OH OH OH OH OH
C=O C=O C=O C=O C=O C=O
R~2 ~R2 R~! ~R2 R\~ " 2 O Plasma N~R COH + 8NH2RNH2 Formula 13 Formula 1 NH2 NH2 NH2 NH2 ~H2 ~H2 Rl Rl Rl Rl Rl Rl NH NH NH NH ~H NH
C=O C=O C=O C=O C=O C=O
~2 R2 N ~ O

'R2 ,CNHR,NH2 + 1 6CH2=CHCOOH

Formula 14 Formula 3 =

W O 97/22631 PCT~US96/20267 COOH COOH COoH
C~OH COOH ~ COOH '~ ,COOH
R~ jR2 R2 ~ R~ R

Rl Rl Rl jRI
5 ~H NH NH NH
O=C C=O O=C C=O
~R~.~R2 ~ " o ~ COOH
Plasma ~ ~ I/~2CNHR,~--R-2~COOH
R2!cNHRlN~ COOH
= 0 ~2'-'--COOH
~l2 ~ R
10O=C C=O
NH NH
Rl Rl ,~2 ,R2 R2 ~2 COOH COOH ~OOH COOH

Formula 15 When acrylonitrile is employed as the monomer, a triazine structure can also be deposited ~not shown). Acrylonitrile offers additional opportunities for formin~
highly branched nt;lw~lh~ of ~e present invention since a triazine structure offers 20 more than two ~tt~rllment points for branching when this structure is anchored on the surface.
By using various combinations of functionalities of the monomers employed, ~e density of the networlc structure can be controlled. ~or example, in the process defined by Formulas 1-7, in Step 1, an amine monomer may be employed.

CA 022l3328 l997-08-l9 W O 97~22631 PCTnUS96/20267 In Step 2, an acid monomer may be employed such as acrylic acid, methacrylic acid, propionic acid, and hexanoic acid. Another class of monomers that ~ can be employed within the scope of the invention, as illustrated in Step 2, are the acrylates. Monomers of this class include but are not limited to methyl acrylate and S methylmethacrylate. The hydrocarbon end of the acid or acrylate is substituted for each hydrogen on the amine to form an amide.
The applicants have found that monomers with higher numbers of carbons in their backbone will result in a network structure having a loose network, thereby increasing inter.~titi~l spacing between plasma film layers, while those with shorter 10 carbon chains will result in tighter networks.
A(l~lition~lly, the applicants have found that when using monomers with more than two functional groups, a much higher level of br~nching can be obtained thereby controlling the network structure. The following examples according to the invention illustrate the employment of dif~.~nt functional clen~itie~ and dirr~ r~,..t backbone 15 chain lengths to provide a network structure having a loose network, thereby ~lcfea~ g h.l~ lilial spacing between plasma film layers as compared to other films for providing access to the functional groups contained therein.
The film network construction can, as an example, be started with a deposition using triethylenetri~mine as the ~m- mer. This monomer can be cleaved at the 20 centrally located CH2 - CH2 bond shown as a dotted line in Formula 16 below.

NH2CH2CH2NHC: H2--CH2NHCH2CH2NH2 Formula 16 l~he substrate surface reslllting from a plasma deposition using triethylene~i~min~ is shown below in Formula 8.

.

W 097/22631 PCTnJS96/20267 Plasma + H2NCH2CH2NHCH2CH2NHCH2CH2NH2 ~ -Formula 16 H
RNRlNH2 Formula 8 The next layer is then added in Step 2 as follows:

RNHR~NH2 + 3~H2=CIHCOOH Plasma Formula 8 Formula 3 R2COH ~
".R2COH
~-RIN--RIN~

Formula 9 -W O 97/22631 PCTrUS96/2~267 At this stage several options are available. Formula 9 can be reacted with Formula 1 to yield Formula 10 or Formula 9 could be reacted with a trifunctionalamine, such as diethylenetri~min~, represented by Formula 17 below, to yield Forrnula 18.
s R2COH ~
R2COH "RNH2 Plasma RIN R~N~R ~OH 3NH ~RNH2 o Formula 9 Formula 17 H2NR ,RNH2 ~,/
~=0 Rl2 ~ ,RNH2 -RN~ RlN~
z ~~'RNH2 Formula 18 The rh~mic~l functional group density of Formula 18 is much dirr~ than the chemical functional group density of Formula 10, which was also derived from Formula g. Thus by mixing and m~trllin~ the reactive functionality 20 ~"monofi~nctional," "difimctional," "trifunctional" etc.) of the monomer employed, plasma deposited film networks with diLr~lel~l morphologies and ~lçnc~ities can be provided. Although multifunctional amines and acrylic acid have been employed to - illustrate the construction of the plasma deposited film network, it will be 3.1)palCl~l to those skilled in the art that the starting film can be constructed from any of the 25 monomers described earlier and combined with the ~plopliate reactive pair shown in the second column of Table I.

-W O 97/22631 PCT~US96/20267 For example, glycidyl methacrylate, Formula 19, could be employed in the first deposition step of the network construction process to yield a surface with the epoxy reactive group, Formula 20, (often referred to as the oxirane group). Thisepoxide group can now be reacted with an amine, for example, Formula 1, and as S suggested in Table I to yield Formula 23 below. Use of a keto ester illustrated by Formula 22 is another source of br~nchin~

~ + CH2-&H-O~(IH=CH2 , ~--R-~CH-~CH2 Formula 19 Formula 20 R CH CH NH R H Plasma ~ R~HR NHR NH
~ ~ ~

Formula20 Formula 1 Formula21 OH -R3 Plasma ~ RCHR2NHR~NH2 + O=C
~ ~R4 Formula 21 Formula 22 W O 97/22631 PCTnJS96~0267 OH ~R3 RCHR2NHR,N=C

Formula 23 s R3 and R4 can be any aliphatic or aromatic groups, ~lirh~tic groups being ~lcr~lled. R3 and R4 can include a reactive chemical functional group and these sites can be employed to continue to build the film network. Thus the construction of the plasma deposited film nelw~ lk can be accomplished by using the a~ idle reactive 10 pairs described in Table I without limitiqtion When a network having a open network (i.e., increased h~ ial spacing between plasma film layers) is desired, monomers can be chosen such that the central chain can be le~lest;llL~d by the notation (CH2)n where "n" is sufficiently large. As illustrated ~elow, when the value of six ~6) is chosen for "n" in the amine, represented 15 by Formula 24, and a value of two (2) is chosen for "n" in the allylic acid m~nomer, Formula 26, allyl acetic acid, Formula 28 in Step 2, results.

~ P1aSma ~ - CH2CH2CH2N H2 Formula 24 Formula 25 WO 97/22631 PCT~US96/20267 ---CH2CH2CH2NH2 + 2CH2=CHCH2CH2COOH Plasma Formula 25 Formula 26 ",CH2CH2CH2CH2COH
- CH2CH2CH2N';'''.~cH2cH2CH2cH2~0H

Formula 27 Step 3 o ,,CH2CH2CH2CH2COH
-CH2CH2CH2N ; CH CH CH CH COH + 2N H2(CH2)6N H2 O

~ormula 27 Formula 24 WO 97/22631 PCT~US96/20267 Plasma ~ ~-cH2cH2cH2cH2cNH(cH2)6NH2 , ~ CH2CH2CH2N" ~CH2CH2CH2CH2,CNH(CH2)6NH2 O

Formula 28 S As the structure shown in Formula 28 illustrates, the film network of the present invention has a loose network, thereby increasing hll~L~ ial spacing between plasma film layers as compared to the crosslink density and i~ spacing obtained when ethylene ~ mine and acrylic acid are reacted using the same three steps illustrated by Formula 29. It will be ~ n~ to those skilled in the art that by using monomers with dirrelelll central chain lengths and difr~.e.lt reactive functionalities, the morphology and the chemical group functionality of the plasma deposited film network can be adjusted in many ways.
o ,,CH2CH2CNH(CH2)2NH2 - -CH2N~
-"CH2CH2,C, NH(cH2)2NH2 O

Formula 29 .

In the collvel,lional wet chemical methods employed for building star polymers, the growth of the structure occurs in a geometric fashion as illustrated in the following chemical process:

,COOE~
-- ~H2 ~(CH2)n H2)n 'COOH

Formula 30 Formula 31 /~OOH
~CH2)n ,N H2 ~ ( ~ )n , (CH2)n 'COOH
(C~H~ 2)n ~ \ 2)n ,COOH
2 \ ~"(C~2)n H23n Formula 32 Formula 33 'COOH

Generally, con~/~,lLional star polymers cannot be m~mlf~r,tured in high volurnes by the method shown in For nulas 30-33 above. Additionally, ~tt~chment of these materials to sllrf~r-~-s is a laborious process. However, using the method of the 20 present invention, the surface of any m~t~ri5~1 can have a highly branched film network covalently bonded to the surface within minlltes Acl~1iti~ n~11y, using the plasma film deposition technique of the present invention, the growth rate of the network can be controlled so that it is something other than strictly geometric. For example, if in the second deposition step previously 25 described in F~ 3 and 4, and in more detail in F~mple 1 below, the acrylic acid deposition process is adjusted such that only part of the amines react, twoobjectives are accomplished. One is that a network structure having an open network, thereby increasing hllel~lilial sp~çin~ n plasma film layers as COl~ d to other films is provided. The other is that some ~ iv~ functional groups inside the 5 n~;Lwwh structure are retained rather than having all functional groups on the pt;~
According to the invention, a method for ~l~v~lllhlg reaction of all functional groups employs short deposition times, which only partially covers the previously deposited film. Another method for controlling the crosslink density and illh~l~liLial 10 spacing of the network structure and ret~inin~ functional reactivity inside the network is shown in Formulas 34-37 below. Here, process conditions are selected such that not all of the functional sites would become growth sites.
For example, by the de-;lea~ g the deposition time in the second step of the process, which in the example is the deposition of acrylic acid, from the 2 minute 15 normal process time to 30 seconds, many of the arnine functional groups deposited in the first layer are left unreacted. Another method of re~ cing the reaction between the amine in the first layer and the acrylic acid being deposited is to reduce the flow of acrylic acid while ms-i"l~i-,i.-g the same process time. As shown in Formula 35 below, if not all functional sites become growth sites, some reactive fùnctional groups 20 remain within the interstices of the network (shown circled).

--RNH2 ~~-RICOH
RNH2 H CH Plasma ~ RICOH
RNH2 ~ O
~- RNH2 ~RICOH
RICOH
O
25Formula 34 Formula 3 Formula 35 w o 97n2631 PCTAUS96/20267 R(~)~RI COH
~--- RN':- RICOH
S ~ O+ NH2RNH2 Plasma R~) RI COH

Formula 35 Formula 1 --RN~,. R,CNHR2NH2 + CH2=CHCOOH Plasma 15 ~ R~ ~(RICOH) \RIcNHR2NH2 o Fo~ 36 :Formula3 W O 97/22631 PCT~US96120267 (RI~O~) ~R,COH
RN RI CNHR2 ~) O
RN~ R~OII) RICI NHR2 N~) O \RICOH

Formula 37 Another method for achieving a plasma deposited film network with chemic~l functional group in the interstices of the film can be illlle~tçd by the following process srheme In this case monomers with the epoxy functional group such as H2 -~N~H2 are employed. Once the three-membered ring is opened in the second step, during deposition of an amine, the epoxy group leaves behind a c~h~mir~l functional group.
For example, as previously shown in Formula 19, glycidyl methacrylate could be employed in the first deposition step of the networlc construction process to yield a 20 surface with the epoxy reactive group, Formula 20, (often referred to as the oxirane group). As shown in Formulas 20-39 below, this surface with the epoxy reactive group, Formula 20, can now be reacted with an amine, for exarnple, Formula 1, and as suggested in Table I to yield Formula 21 below. As Formula 21 illustrates, we are left with a hydroxyl group near the surface and an amine as a t~rmin~l group. Formula 21 W O g7122631 PCT~US96/20267 is also reacted with Formula 19, glycidyl methacrylate, to yield Formula 38, a surface with two epoxy reactive groups. This can again be reacted with an amine to yield, Formula 39, a surface with a plasma deposited film network having functional groups within the interstices of the film layers. t s ~ - ~R-C\H-/CH2 + NH2RINH2 Plasma ~ ~ RCHR2NHR NH

Formula 20 Formula 1 Formula 21 RCHR2NHRINH2 + CH2=CHCI-O-(~H-(;~H2 Plasma ~: O '~"

Formula 21 Formula 19 ,OH ",R-~C~H-",CH NH RNH Plasma -C~-~CH

Formula 38 Formula 1 W O 97/22631 PCTnJS96/20267 OH
OH ,R3CHR2NHRINH2 - ---RCHR2NHRIN~
"R3CHR2NHRINH2 (~H

Formula 39 s In this manner hyd~ y chemical groups can be incorporated in the interstices of the plasma deposited film network while the peripheral chemical groups can be of an entirely di~r~ category, such as an amine, by the choice of the monomer employed in the t~rmin~tion step of the deposition process.
Another method for creating chemical functional groups in the interstices of the plasma deposited film network would follow the scheme illustrated in Formulas 1-41 below. In this process, the network construction is initi~te(l with the deposition of an amine, Formula 1, which is then reacted with a ketone, Formula 40, where the ketone group is located such that the ch~mic~l groups on either side of the ketone 15 group are of differing length and are t~rrnin~t~ ~ with a chemical functional group.
When this ketone is now reacted with another monomer (not shown), the longer arm will react more easily, whereas the shorter arm may become protected by steric hindrance, thereby rem~ining intact within the film structure.

-3s-WO 97122631 PCT/US96/2~267 + NH2RNH2Plasma ~ ~ RNH2 Formula 1Formula 2 ,~CEI2)n,R3 Plasma RNH2 + O=
(CH2)n Formula 2 Formula 40 ,'(CH2)nlR3 ''(CH2)n2R4 Formula 41 wherein n2>>n,.
It is clear from these descriptions that by choosing the particular monomerJprocess step combin~tion~ that are a~ ,pliate for the particular goal inmind, a vast array of structural morphologies, chemical group densities, and location of chemical fimctional groups can be achieved in the plasma deposited film networks described.
The following detailed example ill~ d~es a method of depositing a three-~1im~n~ionsl1 fimctional film network according to the invention.
Ex~mple 1:
A 4.0 liter plasma reaction chamber with internal electrodes driven by a 200 watt RF generator olJeldlillg at 13.56 Mhz is employed. The reaction charnber isconnected to an Alcatel 2020 CP vacuum pump with a purnping capacity of 16 cfm.

A manual tbrottle valve was employed to control the reaction chamber plc;~ule independent of the monomer flow.
Step l: Plasmapolyrnen7~tionofethylene~ min~
Ethylene ~ mine is fed to the reaction chamber by evaporating ethylene 5 ~i~mint? cont~in~ in an Erlenmeyer flask that is m~int~in~cl at 30~C. The plasma polym~ri7~fion is con~ cted at a power setting of 90 watts and a reaction chamber pressure of 420 mTorr. The flow and therefore the re~ nre time of the monomer inthe reaction chamber is controlled by the throttle valve. The throffle valve is adyusted so that the actual plcs~ule in the reaction chamber is 480 mTorr. The process time is 3 minl-tes These films are deposited on 12011m poly~Ly~ e beads. Chemical analysis using a ninhydrin test for primary amines shows a concentration of 1.1 ~mole/gm. The surface area of these beads is 476 cm2/gm. The amine concentrationmeasured equates to a surface concentration of 4 nmoles/cm2. This surface density is equivalent to a monolayer of functional groups on the surface.
15 Step 2: Plasma polymerization of acrylic acid.
In this step, an acrylic acid plasma polym~n7~(1 film is deposited on top of theamine film deposited in Step 1. The acrylic acid is fed to the reactor by bubbling helium through the monomer cont~in~d in an Erlenmeyer flask. The power is set at100 watts, the helium flow rate is 15 cc/min and the ~lCS~ ; is 500 mTorr. The 20 acrylic acid is m~int~ined in a water bath whose t~ elalule is controlled to 45~ C.
The flow and therefore the residence time of the monomer in the reaction chamber is controlled by the throttle valve. The throttle valve is adjusted so that the actual e in the reaction chamber is 580 mTorr. The plasma is pulsed at 10 E~z and a 10% duty cycle is employed. Deposition of acrylic acid on u~ c~Led 180 llm 25 polystyrene beads under these conditions and a process time of 4 minutes results in a functional density of 2.1 ,umol acid groups/gm. This functional density kanslates to 6.8 nmoles/cm2. Since we already have approximately 2.3 nmoles/cm2 of amines on the surface and each amine group can add two acrylic acid groups, the process time for this step is 3 minutes It is assumed that the functional density previously WO 97/22631 PCTlIUS96/20267 d is retained in Step 2. Since each amine group can accommodate two acrylic acid groups, Step 2 will incorporate 2.2 ~lmoles/gm acid groups on the surface.
Step 3: Plasma polymerization of ethylene ~ mine A plasma polymerized film of ethylene ~ qmin~ is deposited using the same 5 conditions described in Step 1. Step 3 deposits one amine functional group at each of the acid functional sites deposited in Step 2. This results in a final amine conr~nfr~tion of 2.2 ~lmoles/gm of amine functional group. Chetnic~l analysis using a ninhydrin test for ~lhll~/ amines shows a cul~celll alion of 2.8 ~lmoIes/gm of amine functional groups on the s~ ce While the foregoing detailed d~srrirtiQn has described several combinations of sequential deposition of particular classes of monomers for a three-~limencionalfunctional film net~,vork in accordance with this invention, it is to be understood that the above description is illu~ liv~ only and not limitin~ of the disclosed invention.
Particularly included is a device and method in accordance with this invention that~5 produces a functional film network having a loose network, thereby increasing x~ spacing bet~,veen plasma film layers as co ~-~ed to other films. The net~vork according to the invention has unique con~ ctin~ p~ lies in that it allows access to functional groups within the interstices of the network. It will be appreciated that various methods to produce various compounds fall within the scope~0 and spirit of this invention.

-3~-

Claims (68)

What is claimed is:

1. A three dimensional film network, comprising:
a plurality of radio frequency discharge plasma film layers, said plasma film layers including a first layer and a second layer disposed immediately adjacent said first layer;
said first layer including a plurality of a first functional group;
and said second layer including a plurality of a second functional group.

2. The three dimensional film network according to Claim 1 including interstitial spaces disposed within said network which provides access to said film layers.

3. The three dimensional film network according to Claim 1 wherein, said first and said second layers are at least partially covalently bonded.

4. The three dimensional film network according to Claim 1 wherein, said first functional group comprises an amine functional group.

5. The three dimensional film network according to Claim 1 wherein, said second functional group is selected from the group consisting of carboxy, carboxylic ester, epoxy, isocyanate, hydroxy and sulfhydryl.

6. The three dimensional film network according to Claim 1 wherein, said first functional group is selected from the group consisting of carboxy, carboxylic ester, epoxy, amine, isocyanate, hydroxy and sulfhydryl.

7. The three dimensional film network according to Claim 1 wherein, said second functional group is selected from the group consisting of carboxy, carboxylic ester, epoxy, amine, isocyanate, hydroxy and sulfhydryl.

8. The three dimensional film network according to Claim 7 wherein, said second functional group is reactive with said first functional group.

9. The three dimensional film network according to Claim 1 wherein, said film network includes a dual branched spatial configuration between said adjacent film layers.

10. The three dimensional film network according to Claim 1 wherein, said three dimensional network includes a triple branched spatial configuration between said adjacent film layers.

11. The three dimensional film network according to Claim 1 wherein, said three dimensional film network includes a quadruple branched spatial configuration between said adjacent film layers.

12. The three dimensional film network according to Claim 1 wherein, said three dimensional film network includes a heterocyclic ring spatial configuration between said adjacent film layers.

13. The three dimensional film network according to Claim 1 wherein, said three dimensional film network includes a linear chain spatial configuration between said adjacent film layers.

14. The three dimensional film network according to Claim 13 wherein, said linear chain includes a plurality of a third functional group selected from the group consisting of carboxy, carboxylic ester, epoxy, amine, isocyanate, hydroxy and sulfhydryl.

15. A three dimensional film network, comprising:
a plurality of radio frequency discharge plasma film layers, said plurality of plasma film layers including alternating pairs of a first layer and a second layer disposed immediately adjacent said first layer;
said first layer including a plurality of a first functional group;
and said second layer including a plurality of a second functional group.

16. The three dimensional film network according to Claim 15 including interstital spaces disposed within said network providing access to said film layers.

17. The three dimensional film network according to Claim 15 wherein, said first and said second layers are at least partially covalently bonded.

18. The three dimensional film network according to Claim 15 wherein, said first functional group comprises an amine functional group.

19. The three dimensional film network according to Claim 15 wherein, said second functional group is selected from the group consisting of carboxy, carboxylic ester, epoxy, isocyanate, hydroxy and sulfhydryl.

20. The three dimensional film network according to Claim 15 wherein, said first functional group is selected from the group consisting of carboxy, carboxylic ester, epoxy, amine, isocyanate, hydroxy and sulfhydryl.

21. The three dimensional film network according to Claim 15 wherein, said second functional group is selected from the group consisting of carboxy, carboxylic ester, epoxy, amine, isocyanate, hydroxy and sulfhydryl.

22. The three dimensional film network according to Claim 21 wherein, said second functional group is reactive with said first functional group.

23. The three dimensional film network according to Claim 15 wherein, said film network includes a dual branched spatial configuration between said adjacent film layers.

24. The three dimensional film network according to Claim 15 wherein, said three dimensional network includes a triple branched spatial configuration between said adjacent film layers.

25. The three dimensional film network according to Claim 15 wherein, said three dimensional film network includes a quadruple branched spatial configuration between said adjacent film layers.

26. The three dimensional film network according to Claim 15 wherein, said three dimensional film network includes a heterocyclic ring spatial configuration between said adjacent film layers.

27. The three dimensional film network according to Claim 15 wherein, said three dimensional film network includes a linear chain spatial configuration between said adjacent film layers.

28. The three dimensional film network according to Claim 27 wherein, said linear chain includes a plurality of a third functional group selected from the group consisting of carboxy, carboxylic ester, epoxy, amine, isocyanate and hydroxy.

29. A substrate structure, comprising:
a substrate having a surface thereon; and a plurality of radio frequency discharge plasma film layers sequentially deposited on said substrate surface, said plasma film layers including a first layer and a second layer disposed immediately adjacent said first layer, said first layer including a plurality of a first functional group, said second layer including a plurality of a second functional group.

30. The substrate structure according to Claim 29 including interstitial spaces disposed within said film layers.

31. The substrate structure according to Claim 29 wherein, said first and said second layers are at least partially covalently bonded.

32. The substrate structure according to Claim 29 wherein, said first functional group comprises an amine functional group.

33. The substrate structure according to Claim 29 wherein, said second functional group is selected from the group consisting of carboxy, carboxylic ester, epoxy, isocyanate, hydroxy and sulfhydryl.

34. The substrate structure according to Claim 29 wherein, said first functional group is selected from the group consisting of carboxy, carboxylic ester, epoxy, amine, isocyanate, hydroxy and sulfhydryl.

35. The substrate structure according to Claim 29 wherein, said second functional group is selected from the group consisting of carboxy, carboxylic ester, epoxy, amine, isocyanate, hydroxy and sulfhydryl.

36. The substrate structure according to Claim 35 wherein, said second functional group is reactive with said first functional group.

37. The substrate structure according to Claim 29 wherein, said substrate structure includes a dual branched spatial configuration between said adjacent film layers.

38. The substrate structure according to Claim 29 wherein, said substrate structure includes a triple branched spatial configuration between said adjacent film layers.

39. The substrate structure according to Claim 29 wherein, said substrate structure includes a quadruple branched spatial configuration between said adjacent film layers.

40. The substrate structure according to Claim 29 wherein, said substrate structure includes a heterocyclic ring spatial configuration between said adjacent film layers.

41. The substrate structure according to Claim 29 wherein, said substrate structure includes a linear chain spatial configuration between said adjacent film layers.

42. The substrate structure according to Claim 41 wherein, said linear chain includes a plurality of a third functional group selected from the group consisting of carboxy, carboxylic ester, epoxy, amine, isocyanate, hydroxy and sulfhydryl.

43 . A method for sequentially depositing a three-dimensional functional film network on a substrate, comprising the steps:
positioning a substrate having a surface thereon in a radio frequency plasma discharge apparatus;
inserting into said radio frequency plasma discharge apparatus a first plasma medium, said first plasma medium comprising a first compound selected from the group consisting of ammonia, unsaturated amine, primary amine, aliphatic diamine, polyalkylene polyamine, aminosilane, heterocyclic amine, nitrile, pyrrole, pyrrolidine, saturated carboxylic acid, unsaturated carboxylic acid, carboxylic ester, keto ester and mixtures thereof;
subjecting said first plasma medium to a first radio frequency electric field whereby a first plasma film layer is deposited on said substrate surface, said first plasma film layer including a plurality of a first functional group;
inserting into said radio frequency plasma discharge apparatus a second plasma medium, said second plasma medium comprising a second compound selected from the group consisting of ammonia, unsaturated amine, primary amine, aliphatic diamine, polyalkylene polyamine, aminosilane, heterocyclic amine, nitrile, pyrrole, pyrrolidine, saturated carboxylic acid, unsaturated carboxylic acid, carboxylic ester, keto ester and mixtures thereof;
subjecting said second plasma medium to a second radio frequency electric field whereby a second plasma film layer is deposited on saidsubstrate surface, said second plasma film layer including a plurality of a second functional group.

44. The method according to Claim 43 including the further step of continuing said sequential depositions of said first and said second plasma film layers until a predetermined plasma film network is deposited on said substrate.

45. The method according to Claim 43 wherein, said first plasma medium comprises oxygen.

46. The method according to Claim 43 wherein, said first plasma medium comprises carbon dioxide.

47. The method according to Claim 43 wherein, said first plasma medium comprises water.

48. The method according to Claim 43 wherein, said first plasma medium comprises a mixture of a hydrocarbon and said first compound.

49. The method according to Claim 43 wherein, said second plasma medium comprises oxygen.

50. The method according to Claim 43 wherein, said second plasma medium comprises carbon dioxide.

51. The method according to Claim 43 wherein, said second plasma medium comprises water.

52. The method according to Claim 43 wherein, said second plasma medium comprises a mixture of a hydrocarbon and said first compound.

53. The method according to Claim 43 wherein, said first plasma medium comprises a third compound selected from the group consisting of ammonia, unsaturated amine, primary amine, aliphatic diamine, polyalkylene polyamine, aminosilane, heterocyclic amine, nitrile, pyrrole, pyrrolidine and mixtures thereof.

54. The method according to Claim 43 wherein, said first plasma medium comprises a mixture of a hydrocarbon and said third compound.

55. The method according to Claim 53 wherein, said first functional group comprises an amine functional group.

56. The method according to Claim 55 wherein, said second plasma medium comprises a fourth compound selected from the group consisting of saturated carboxylic acid, unsaturated carboxylic acid, carboxylic ester, keto ester and mixtures thereof.

57. The method according to Claim 56 wherein, said second plasma medium comprises a mixture of a hydrocarbon and said fourth compound.

58. The method according to Claim 55 wherein, said second plasma medium comprises oxygen.

59. The method according to Claim 56 wherein, said second functional group is selected from the group consisting of carboxy, carboxylic ester, epoxy,isocyanate, hydroxy and sulfhydryl.

60. The method according to Claim 43 wherein, said first functional group is selected from the group consisting of carboxy, carboxylic ester, epoxy, amine, isocyanate, hydroxy and sulfhydryl.

61. The method according to Claim 43 wherein, said second functional group is selected from the group consisting of carboxy, carboxylic ester, epoxy,amine, isocyanate, hydroxy and sulfhydryl.

62. The method according to Claim 43 wherein, said second functional group is reactive with said first functional group.

63. The method according to Claim 43 wherein, said three dimensional film network includes a dual branched spatial configuration between said adjacent film layers.

64. The method according to Claim 43 wherein, said three dimensional network includes a triple branched spatial configuration between said adjacent film layers.

65. The method according to Claim 43 wherein, said three dimensional film network includes a quadruple branched spatial configuration between said adjacent film layers.

66. The method according to Claim 43 wherein, said three dimensional film network includes a heterocyclic ring spatial configuration between said adjacent film layers.

67. The method according to Claim 43 wherein, said three dimensional film network includes a linear chain spatial configuration between said adjacent film layers.

68. The method according to Claim 67 wherein, said linear chain includes a plurality of a third functional group selected from the group consisting of carboxy, carboxylic ester, epoxy, amine, isocyanate, hydroxy and sulfhydryl.