Aromatic Polyamide Films for Transparent Flexible Substrates

Abstract

The present invention is directed toward transparent films prepared from soluble aromatic copolyamides with glass transition temperatures greater than 300° C. The copolyamides, which contain pendant carboxylic groups are solution cast into films using N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidinone (NMP), or other polar solvents. The films are thermally cured at temperatures near the copolymer glass transition temperature. After curing, the polymer films display transmittances >80% from 400 to 750 nm, have coefficients of thermal expansion of less than 20 ppm, and are solvent resistant. The films are useful as flexible substrates for microelectronic devices.

Claims

1. A process for manufacturing a thermally and dimensionally stable, transparent aromatic copolyamide film characterized by the steps of: a) forming a mixture of two or more aromatic diamines where at least one of the diamines contains one or more free carboxylic acid groups, such that the amount of carboxylic acid containing diamine is greater than approximately 1 mole percent and less than approximately 10 mole percent of the total diamine mixture; b) dissolving the aromatic diamine mixture in a polar solvent; c) reacting the diamine mixture with at least one aromatic diacid dichloride, wherein hydrochloric acid and a polyamide solution is generated; d) eliminating the hydrochloric acid with a reagent; e) casting the polyamide solution into a film; and, f) curing the film at a temperature which allows the film to be solvent resistant.

2. The process of claim 1 wherein the diamine containing a carboxylic acid group is 4,4′-diaminodiphenic acid or 3,5-diaminobenzoic acid.

3. The process of claim 1 wherein the aromatic diamine is selected from the group comprising 4,4′-diamino-2,2′-bistrifluoromethylbenzidine, 9,9-bis(4-aminophenyl)fluorine, and 9,9-bis(3-fluoro-4-aminophenyl)fluorine, 4,4′-diamino-2,2′-bistrifluoromethoxylbenzidine, 4,4′-diamino-2,2′-bistrifluoromethyldiphenyl ether, bis-(4-amino-2-trifluoromethylphenyloxyl) benzene, and bis-(4-amino-2-trifluoromethylphenyloxyl) biphenyl.

4. The process of claim 1 wherein the polar solvent is N,N-dimethylacetamide or N-methyl-2-pyrrolidinone, and the temperature is at least approximately 90% of the glass transition temperature of the film.

5. The process of claim 1 wherein the at least one aromatic diacid dichloride is selected from the group comprising terephthaloyl dichloride, isophthaloyl dichloride, 2,6-naphthaloyl dichloride, and 4,4,-biphenyldicarbonyl dichloride.

6. The process of claim 4, wherein the temperature is between approximately 90% and approximately 110% of the glass transition temperature of the film.

7. The process of claim 1 wherein the polar solvent is an inorganic solvent.

8. The process of claim 1, wherein the reaction of the reagent with the hydrochloric acid forms a volatile product and the film is cast directly from the reaction mixture.

9. The process of claim 8, wherein the reagent is propylene oxide.

10. The process of claim 1, wherein the film is produced in the absence of inorganic salt.

11. A thermally and dimensionally stable, solvent resistant, transparent aromatic copolyamide film produced in accordance with the process of claim 1.

12. An aromatic copolyamide characterized by at least two repeat units of general formulas (I) and (II): ##STR00012## wherein n=1 to 4; wherein the ratio of X and Y is selected so that the copolyamide is soluble in polar aprotic solvents and can be solution cast into a clear film that has a CTE <20 ppm/° C.; wherein Ar.sub.1 is selected from the group comprising: ##STR00013## wherein p=4, q=3, and wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 are selected from the group comprising hydrogen, halogen (fluoride, chloride, bromide, and iodide), alkyl, substituted alkyl such as halogenated alkyls, nitro, cyano, thioalkyl, alkoxy, substituted alkoxy such as halogenated alkoxy, aryl, or substituted aryl such as halogenated aryls, alkyl ester and substituted alkyl esters, and combinations thereof, wherein G.sub.1 is selected from a group comprising a covalent bond; a CH.sub.2 group; a C(CH.sub.3).sub.2 group; a C(CF.sub.3).sub.2 group; a C(CX.sub.3).sub.2 group, wherein X is a halogen; a CO group; an O atom; a S atom; a SO.sub.2 group; a Si (CH.sub.3).sub.2 group; 9,9-fluorene group; substituted 9,9-fluorene; and an OZO group, wherein Z is a aryl group or substituted aryl group, such as phenyl group, biphenyl group, perfluorobiphenyl group, 9,9-bisphenylfluorene group, and substituted 9,9-bisphenylfluorene; wherein Ar.sub.2 is selected from the group comprising: ##STR00014## wherein p=4, wherein R.sub.6, R.sub.7, R.sub.8 are selected from the group comprising hydrogen, halogen (fluoride, chloride, bromide, and iodide), alkyl, substituted alkyl such as halogenated alkyls, nitro, cyano, thioalkyl, alkoxy, substituted alkoxy such as a halogenated alkoxy, aryl, substituted aryl such as halogenated aryls, alkyl ester, and substituted alkyl esters, and combinations thereof, wherein G.sub.2 is selected from a group comprising a covalent bond; a CH.sub.2 group; a C(CH.sub.3).sub.2 group; a C(CF.sub.3).sub.2 group; a C(CX.sub.3).sub.2 group, wherein X is a halogen; a CO group; an O atom; a S atom; a SO.sub.2 group; a Si (CH.sub.3).sub.2 group; 9,9-fluorene group; substituted 9,9-fluorene; and an OZO group, wherein Z is a aryl group or substituted aryl group, such as phenyl group, biphenyl group, perfluorobiphenyl group, 9,9-bisphenylfluorene group, and substituted 9,9-bisphenylfluorene; wherein Ar.sub.3 is selected from the group comprising: ##STR00015## wherein m=1 or 2, wherein t=1 to 3, wherein R.sub.9, R.sub.10, R.sub.11 are selected from the group comprising hydrogen, halogen (fluoride, chloride, bromide, and iodide), alkyl, substituted alkyl such as halogenated alkyls, nitro, cyano, thioalkyl, alkoxy, substituted alkoxy such as halogenated alkoxy, aryl, substituted aryl such as halogenated aryls, alkyl ester, and substituted alkyl esters, and combinations thereof, wherein G.sub.3 is selected from a group comprising a covalent bond; a CH.sub.2 group; a C(CH.sub.3).sub.2 group; a C(CF.sub.3).sub.2 group; a C(CX.sub.3).sub.2 group, wherein X is a halogen; a CO group; an O atom; a S atom; a SO.sub.2 group; a Si (CH.sub.3).sub.2 group; 9,9-fluorene group; substituted 9,9-fluorene; and an OZO group, wherein Z is a aryl group or substituted aryl group, such as phenyl group, biphenyl group, perfluorobiphenyl group, 9,9-bisphenylfluorene group, and substituted 9,9-bisphenylfluorene.

13. The copolyamide of claim 12, wherein X is the molar ratio of the repeat structure (I), wherein X is from 0.90 to 0.99, and Y is the molar ratio of the repeat structure (II), wherein Y is from 0.01 to 0.10.

14. The copolyamide of claim 12, wherein the copolymer contains multiple repeat units with structures (I) and (II) where Ar.sub.1, Ar.sub.2, and Ar.sub.3 are the same or different.

15. The copolyamide of claim 12 wherein the film transparency is >80% at 400 and 750 nm before a resulting film is cured.

16. The copolyamide of claim 12 wherein a resulting film transparency is >80% at 400 and 750 nm after a film is cured.

17. The copolyamide of claim 16 wherein the film curing temperature is held at least approximately 300° C. for at least approximately 3 minutes.

18. The copolyamide of claim 16 wherein the film transparency is ≥88% at 550 nm after the film is cured.

19. The copolyamide of claim 12 wherein a resulting film is cured at a temperature between approximately 90% and approximately 110% of the glass transition temperature of the film.

20. The copolyamide of claim 12 wherein a resulting film is cured at a temperature which allows the film to be chemically resistant to polar solvents.

21. The copolyamide of claim 12 wherein a resulting film coefficient of thermal expansion is less than approximately 10 ppm/° C.

22. The copolyamide of claim 12 wherein a resulting film undergoes no significant loss in transparency when heated for at least one hour at 300° C.

23. A transparent film having a glass transition temperature greater than approximately 300° C. and a coefficient of thermal expansion of less than approximately 20 ppm/° C., consisting essentially of an aromatic copolyamide characterized by: at least two repeat structures, wherein one of the repeat structures is repeat structure (V) ##STR00016## wherein n=1 to 4; where Y is the molar ratio of the repeat structure (V) with respect to all other repeat structures, and Y is from 0.01 to 0.10; wherein Ar.sub.1 is selected from the group comprising: ##STR00017## wherein p=4, q=3, and wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 are selected from the group comprising hydrogen, halogen (fluoride, chloride, bromide, and iodide), alkyl, substituted alkyl such as halogenated alkyls, nitro, cyano, thioalkyl, alkoxy, substituted alkoxy such as a halogenated alkoxy, aryl, or substituted aryl such as halogenated aryls, alkyl ester and substituted alkyl esters, and combinations thereof, wherein G.sub.1 is selected from a group comprising a covalent bond; a CH.sub.2 group; a C(CH.sub.3).sub.2 group; a C(CF.sub.3).sub.2 group; a C(CX.sub.3).sub.2 group, wherein X is a halogen; a CO group; an O atom; a S atom; a SO.sub.2 group; a Si (CH.sub.3).sub.2 group; 9,9-fluorene group; substituted 9,9-fluorene; and an OZO group, wherein Z is a aryl group or substituted aryl group, such as phenyl group, biphenyl group, perfluorobiphenyl group, 9,9-bisphenylfluorene group, and substituted 9,9-bisphenylfluorene; wherein Ar.sub.2 is selected from the group comprising: ##STR00018## wherein p=4, wherein R.sub.6, R.sub.7, R.sub.8 are selected from the group comprising hydrogen, halogen (fluoride, chloride, bromide, and iodide), alkyl, substituted alkyl such as halogenated alkyls, nitro, cyano, thioalkyl, alkoxy, substituted alkoxy such as a halogenated alkoxy, aryl, substituted aryl such as halogenated aryls, alkyl ester, and substituted alkyl esters, and combinations thereof, wherein G.sub.2 is selected from a group comprising a covalent bond; a CH.sub.2 group; a C(CH.sub.3).sub.2 group; a C(CF.sub.3).sub.2 group; a C(CX.sub.3).sub.2 group, wherein X is a halogen; a CO group; an O atom; a S atom; a SO.sub.2 group; a Si (CH.sub.3).sub.2 group; 9,9-fluorene group; substituted 9,9-fluorene; and an OZO group, wherein Z is a aryl group or substituted aryl group, such as phenyl group, biphenyl group, perfluorobiphenyl group, 9,9-bisphenylfluorene group, and substituted 9,9-bisphenylfluorene; wherein Ar.sub.3 is selected from the group comprising: ##STR00019## wherein m=1 or 2, wherein t=1 to 3, wherein R.sub.9, R.sub.10, R.sub.11 are selected from the group comprising hydrogen, halogen (fluoride, chloride, bromide, and iodide), alkyl, substituted alkyl such as halogenated alkyls, nitro, cyano, thioalkyl, alkoxy, substituted alkoxy such as halogenated alkoxy, aryl, substituted aryl such as halogenated aryls, alkyl ester, and substituted alkyl esters, and combinations thereof, wherein G.sub.3 is selected from a group comprising a covalent bond; a CH.sub.2 group; a C(CH.sub.3).sub.2 group; a C(CF.sub.3).sub.2 group; a C(CX.sub.3).sub.2 group, wherein X is a halogen; a CO group; an O atom; a S atom; a SO.sub.2 group; a Si (CH.sub.3).sub.2 group; 9,9-fluorene group; substituted 9,9-fluorene; and an OZO group, wherein Z is a aryl group or substituted aryl group, such as phenyl group, biphenyl group, perfluorobiphenyl group, 9,9-bisphenylfluorene group, and substituted 9,9-bisphenylfluorene.

24. The transparent film of claim 23, wherein the film thickness is greater than approximately 10 μm.

25. The transparent film of claim 24, wherein the film thickness is between approximately 10 μm and approximately 100 μm.

26. The transparent film of claim 23, wherein the film is adhered to a substrate and wherein the film thickness is greater than approximately 5 μm.

27. The transparent film of claim 26, wherein the substrate is a glass film with a thickness greater than approximately 50 μm.

28. The transparent film of claim 23, wherein the film is cured between approximately 90% and approximately 110% of the glass transition temperature of the film.

29. The transparent film of claim 23, wherein the optical transmittance is greater than approximately 80% between 400 nm and 750 nm.

30. The transparent film of claim 23, wherein the coefficient of thermal expansion is less than approximately 10 ppm/° C.

Description

DETAILED DESCRIPTION

[0039] The present invention is directed toward transparent films prepared from aromatic copolyamides. A polyamide is prepared via a condensation polymerization in a solvent, where the hydrochloric acid generated in the reaction is trapped by a reagent like propylene oxide (PrO). The film can be made directly from the reaction mixture, without the need for isolating and re-dissolving the polyamide. Colorless films can be prepared by casting procedures directly from the polymerization solutions. The product of the reaction of the hydrochloric acid with the PrO is eliminated during the removal of the solvent. These films display low CTEs as cast and do not need to be subjected to stretching. By carefully manipulating the ratio of the monomers used to prepare the copolyamides, the CTEs and T.sub.gs of the resulting copolymers and the optical properties of their solution cast films can be controlled. It is particularly surprising that a film can be cured at an elevated temperature when free carboxylic acid side groups exist along the polymer chains. If the reaction of the reagent with the hydrochloric acid does not form volatile products, the polymer is isolated from the polymerization mixture by precipitation and re-dissolved by a polar solvent (without the need for inorganic salts) and cast in the film. If the reaction of the reagent with the hydrochloric acid does form volatile products, the film can be directly cast. One example, above, of a reagent that forms volatile products is PrO.

[0040] Representative and illustrative examples of the useful aromatic diacid dichlorides in the invention are:

##STR00009##

[0041] Representative and illustrative examples of the useful aromatic diamines in the invention are:

##STR00010## ##STR00011##

EXAMPLES

[0042] Example 1. This example illustrates the general procedure for the preparation of a copolymer from TPC, IPC and PFMB (70%/30%/100% mol) via solution condensation.

[0043] To a 250 ml, three necked, round bottom flask, equipped with a mechanical stirrer, a nitrogen inlet and an outlet, are added PFMB (3.2024 g, 0.01 mol) and dried DMAc (45 ml). After the PFMB dissolves completely, IPC (0.6395 g 0.003 mol) is added to the solution at room temperature under nitrogen, and the flask wall is washed with DMAc (1.5 ml). After 15 minutes, TPC (1.4211 g, 0.007 is added to the solution, and the flask wall is again washed with DMAc (1.5 ml). The viscosity of the solution increases until the mixture forms a gel. After adding PrO (1.4 g, 0.024 mol), the gel is broken up under stirring to form a viscous, homogenous solution. After stirring at room temperature for another 4 hours, the resulting copolymer solution can be directly cast into film.

[0044] Example 2. This example illustrates the general procedure for the preparation of a copolymer from TPC, PFMB, and FDA (100%/80%/20% mol) via solution condensation.

[0045] To a 100 ml, four necked, round bottom flask, equipped with a mechanical stirrer, a nitrogen inlet and outlet, are added PFMB (1.0247g, 3.2 mmol), FDA (0.02788g, 0.8 mmol), and dried DMAc (20 ml) at room temperature under nitrogen. After the PFMB dissolves completely, TPC (0.8201g 4.04 mmol) is added to the solution, and the flask wall is washed with DMAc (5.0 ml). The viscosity of the solution increases until the mixture forms a gel. After adding PrO (0.5 g, 8.5 mmol), the gel is broken up under stirring to form a viscous, homogenous solution. After stirring for another 4 hours at room temperature, the resulting copolymer solution can be directly cast into film.

[0046] Example 3. This example illustrates the general procedure for the preparation of a copolymer from TPC, IPC, DADP, and PFMB (70%/30%/3%/97% mol) via solution condensation.

[0047] To a 250 ml, three necked, round bottom flask, equipped with a mechanical stirrer, a nitrogen inlet and outlet, are added PFMB (3.1060 g, 0.0097 mol), DADP (0.0817 g, 0.0003 mol), and dried DMAc (45 ml) at room temperature under nitrogen. After the PFMB dissolves completely, IPC (0.6091 g 0.003 mol) is added to the solution, and the flask wall is washed with DMAc (1.5 ml). After 15 minutes, TPC (1.4211 g, 0.007 mol) is added, and the flask wall is again washed with DMAc (1.5 ml). The viscosity of the solution increases until the mixture forms a gel. After adding PrO (1.4 g, 0.024 mol), the gel is broken up under stirring to form a viscous, homogenous solution. After stirring for another 4 hours at room temperature, the resulting copolymer solution can be directly cast into film.

[0048] Example 4. This example illustrates the general procedure for the preparation of a copolymer from TPC, IPC, DAB, and PFMB (75%/25%/5%/95% mol) via solution condensation.

[0049] To a 250 ml, three necked, round bottom flask, equipped with a mechanical stirrer, a nitrogen inlet and outlet, are added PFMB (3.0423 g, 0.0095 mol), DAB (0.0761 g, 0.0005 mol), and dried DMAc (45 ml) at room temperature under nitrogen. After the PFMB dissolves completely, IPC (0.5076 g 0.0025 mol) is added to the solution, and the flask wall is washed with DMAc (1.5 ml). After 15 minutes, TPC (1.5227 g, 0.0075 mol) is added, and the flask wall is again washed with DMAc (1.5 ml). The viscosity of the solution increases until the mixture forms a gel. After adding PrO (1.4 g, 0.024 mol), the gel is broken up under stirring to form a viscous, homogenous solution. After stirring for another 4 hours at room temperature, the resulting copolymer solution can be directly cast into film.

[0050] It is to be understood, although the temperature provided in the examples is room temperature, the temperature range can be between approximately −20° C. to approximately 50° C., and in some embodiments from approximately 0° C. to approximately 30° C.

Preparation and Characterization of the Polymer Films

[0051] The polymer solution can be used directly for the film casting after polymerization. For the preparation of small films in a batch process, the solution is poured on a flat glass plate or other substrate, and the film thickness is adjusted by a doctor blade. After drying on the substrate, under reduced pressure, at 60° C. for several hours, the film is further dried at 200° C. under protection of dry nitrogen flow for 1 hour. The film is cured by heating at or near the polymer T.sub.g under vacuum or in an inert atmosphere for several minutes. Mechanical removal from the substrate yields a free standing film greater than approximately 10 μm thick. The thickness of the free standing films can be adjusted by adjusting the solids content and viscosity of the polymer solution. It is to be understood that the film can be cured at any temperature between approximately 90% and approximately 110% of the T.sub.g. It is also understood that the batch process can be modified so that it can be carried out continuously by a roll-to-roll process by techniques known to those skilled in the art.

[0052] In one embodiment of this invention, the polymer solution may be solution cast onto a reinforcing substrate like thin glass, silica, or a microelectronic device. In this case, the process is adjusted so that the final polyamide film thickness is greater than approximately 5 μm.

[0053] The CTE and T.sub.g are measured with a thermal mechanical analyzer (TA Q 400 TMA). The sample film has a thickness of approximately 20 μm, and the load strain is 0.05N. In one embodiment, the free standing film thickness is between approximately 20 μm and approximately 125 μm. In one embodiment, the film is adhered to a reinforcing substrate and the film thickness is <20 μm. In one embodiment, the CTE is less than approximately 20 ppm/° C., but it is understood that in other embodiments, the CTE is less than approximately 15 ppm/° C., less than approximately 10 ppm/° C., and less than approximately 5 ppm/° C. It is to be understood that within these embodiments the CTE can be less than approximately 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, or 5 ppm/° C. The experimentally derived CTEs are the average of the CTE obtained from room temperature to about 250° C.

[0054] Film transparency is measured by determining the transmittance of a 10 μm thick film from 400 to 750 nm with a UV-Visible spectrometer (Shimadzu UV 2450).

[0055] The solvent resistance of the film is determined by immersing it in a selected solvent for 30 minutes at room temperature. The film is considered solvent resistant if it is substantially free of surface wrinkles, swelling, or any other visible damage after immersion. The films are useful as substrates for flexible electronic devices.

[0056] To determine the ratio of reactants necessary to obtain a soluble copolyamide that can be solution cast into a colorless film with a T.sub.g>300 C, a CTE <20 ppm, and a transmittance >80% from 400 to 750 nm, a preliminary study can be conducted where the amount of reactants that do not contain free carboxyl groups are varied in a systematic manner. The properties of the films of the copolymers obtained are measured in order to determine suitable copolymer candidates (base polymers) for the incorporation of free carboxyl groups. Such studies are well understood by those skilled in the art. The following tables show comparative examples of such studies used to determine some on the base polymers utilized in the present invention.

TABLE-US-00001 TABLE 1 Properties of films based on TPC/IPC/PFMB TPC/IPC/PFMB CTE ppm/° C. T.sub.g ° C. Film Transparency 100/0/100 — — Opaque 90/10/100 — — Opaque 80/20/100 — — Opaque 75/25/100 — — Opaque 70/30/100 7.4 336 Clear (Example 1) 60/40/100 8.0 323 Clear 50/50/100 12.2 330 Clear 40/60/100 22.4 336 Clear 30/70/100 32.6 319 Clear 20/80/100 27.9 326 Clear 10/90/100 30.1 325 Clear 0/100/100 34.2 327 Clear

TABLE-US-00002 TABLE 2 Properties of films based on TPC/FDA/PFMB TPC/FDA/PFMB CTE ppm/° C. T.sub.g ° C. Film Transparency 100/0/100 — — Opaque 100/10/90 — — Opaque 100/20/80 5.8 365 Clear (Example 2) 100/30/70 5.1 370 Clear 100/50/50 13.1 391 Clear 100/70/30 18.3 406 Clear 100/80/20 26.7 404 Clear 100/90/10 33.2 410 Clear 100/100/0 >40 >410 Clear

[0057] To determine the minimum amount of carboxyl groups necessary to thermally crosslink the copolymer without significantly changing the properties, a second preliminary study can be conducted where various amounts of a reactant containing free carboxyl groups are copolymerized with the mixture of reactants used to prepare the base polymer. Films of the copolymers obtained and their properties determined. For example, various amounts of DADP were copolymerized with the reactants used in the preparation of the base polymer made from a mixture of TPC, IPC and PFMB in a 70/30/100 ratio (Example 1). The films of the copolymers obtained containing DADP were thermally treated at 330° C. for 5 minutes. After curing, the film resistance to NMP was evaluated. The results are shown in Table 3.

TABLE-US-00003 TABLE 3 NMP resistance test for TPC/IPC/PFMB/DADP polymer films TPC/IPC/PFMB/DADP NMP resistance 70/30/99/1 No 70/30/97/3 (Example 3) Yes 70/30/95/5 Yes

[0058] The properties of polymer films based on Example 3 after curing are shown in Table 4. The composition of a copolymer containing DAB (Example 4), which was determined in an analogous manner, is also shown in Table 4 along with the properties of cured films of this polymer.

TABLE-US-00004 TABLE 4 Properties of films after curing Example 3 Example 4 TPC 70 75 IPC 30 25 PFMB 97 95 DADP 3 0 DAB 0 5 Curing Conditions 330° C. × 5 minutes 330° C. × 10 minutes T.sub.g (° C.) 334 350 CTE (ppm/° C.) 7 12 T % at 400 nm 80 81 DMAc resistance Yes Yes NMP resistance Yes Yes DMSO resistance Yes Yes

[0059] The cured films of this invention are resistant to both inorganic and organic solvents. The film solvent resistance can be evaluated quickly by analyzing the resistance to NMP, a commonly used strong solvent. It has been found that films resistant to this solvent are also resistant to other polar solvents.

[0060] The following are exemplary polymers that can be used in this invention—1) about 50 to about 70 mol % TPC, about 30 to about 50 mol % IPC, about 90 to about 99 mol % PFMB, and about 1 to about 10 mol % 4,4′-Diaminodiphenic acid (DADP); 2) about 50 to about 70 mol % TPC, about 25 to about 50 mol % IPC, about 90 to about 96 mol % PFMB, and about 4 to about 10 mol % 3,5-diaminobenzoic acid (DAB); 3) about 100 mol % TPC, about 25 to about 85 mol % PFMB, about 15 to about 50 mol % 9,9-Bis(4-aminophenyl)fluorine (FDA), and about 1 to about 10 mol % DADP; and 4) about 100 mol % TPC, about 50 to about 85 mol % PFMB, about 15 to about 50 mol % FDA, and about 4 to about 10 mol % DAB.

[0061] The embodiments have been described, hereinabove. It will be apparent to those skilled in the art that the above methods and apparatuses may incorporate changes and modifications without departing from the general scope of this invention. It is intended to include all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof. Although the description above contains much specificity, this should not be construed as limiting the scope of the invention, but as merely providing illustrations of some of the embodiments of this invention. Various other embodiments and ramifications are possible within its scope.

[0062] Furthermore, notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.