Materials 3,3 ’ ,4,4 ’ -benzophenone tetracarboxylic

The idea of synthesizing imide oligomers which carry acetylenic terminations appeared attractive because homopolymerization through acetylenic endgroups occurs without any volatile evolution and provides materials with good properties. Landis et. al (8,9) published the synthesis of such acetylene terminated imide oligomers from benzophenone tetracarboxylic anhydride, aromatic diamine and 3-ethynylaniline via the classical route. As usual, the amide acid is formed as an intermediate which, after chemical cyclodehydration, provides the polymide. Since ethynyl-terminated polyimide is used as a matrix resin for fiber composites, processing is possible via the amide acid, which is soluble in acetone, or via the fully imidized prepolymer, which is soluble in NMP. The chemical structure of the fully imidized ethynyl-terminated polyimide is provided in Fig. 44. 

Poly(phenylquinoxaline—amide—imides) are thermally stable up to 430°C and are soluble in polar organic solvents (17). Transparent films of these materials exhibit electrical insulating properties. Quinoxaline—imide copolymer films prepared by polycondensation of 6,6,-methylene bis(2-methyl-3,l-benzoxazine-4-one) and 3,3, 4,4 -benzophenone tetracarboxylic dianhydride and 4,4,-oxydianiline exhibit good chemical etching properties (18). The polymers are soluble, but stable only up to 200—300°C. 

Starting materials and solvents were purchased from Aldrich Chemical Co. acetonitrile (ACN), N,N-dimethylformamide (DMF), and N-methyl-2-pyrrolidone (NMP) were obtained anhydrous in Sure/Seal bottles and used as received. The polyamic acid of PMDA-ODA (2545 Pyralin) was supplied by DuPont. The soluble polyimide XU-218, derived from 3,3, 4,4 -benzophenone tetracarboxylic dianhydride (BTDA) and diamino-1,1,3-trimethyl-3-phenylindan isomers (DAPI) was purchased from Ciba-Geigy Corp. The acetylene terminated imide oligomer powder (Thermid MC-600) derived from BTDA, aminophenylacetylene, and 1,3-bis (2-aminophenoxy) benzene (APB) was obtained from National Starch and Chemical Company. Kapton Type II (PMDA-ODA) films were obtained from DuPont Co., Apical polyimide films were obtained from Allied Corp., and Upilex Type-S and Type-R polyimide films derived from 3,3, 4,4 -biphenyl tetracarboxylic dianhydride (BPDA) plus p-phenylenediamine (PDA) and ODA, respectively were obtained from ICI Americas Inc. 

PAA/PAE Blends. PAAs and PAEs were blended and dissolution rate of their films was measured. Some of the mixture films were peeled off from the substrate during the dissolution. The results for two examples of the mixtures are shown in Figure 2. It can be seen from Figure 2 that the dissolution rate of the films for blends increases with the content of PAA as expected. We selected a polymer of blend ratio of PAA/PAE 50/50 for PAA(BTDA/DDE)/PAE(BTD-Me/DDE) as a base polymer with moderate dissolution rate, where BTDA is benzophenone tetracarboxylic acid dianhaydride, DDE is diphenyldiaminoether, and BTD-Me is benzophenone tetracarboxylic acid dimethyl ester. The exposure characteristic for a photosensitive material composed of the blend as a base polymer and TBP-DNQ... 

Co.), dichloromaleic anhydride (Aldrich Chem. Co.), and benzophenone tetracarboxylic dianhydride (Gulf Oil). These are commercially available materials and they were used as supplied by the producers. 

Materials The materials in this work includ< a lyotropic polyamide (PBTA) composed of terephthaloyl dichloride and 2,2 -dimethyI-4,4-diamino-biphenyl two amorphous polyimides respectively con sting of 3,3 4,4-benzophenone tetracarboxylic dianhydride (BTDA) and 2,3,5,6-tetrameth -p-phenylene diamine (TMPD), as well as 4,4 -(hexafluoroisopropylidene)>bis(phthalic anhydride) (6FDA) and 2,2-dimethyl-4,4-diamino-biphenyl (DMDB) and the block copolymers composed of PBTA and those two polyimides with various compositions. Ilie PBTA/PI block copolymers and the corresponding homopolymers were prepared according to our previous work(79). 

STRUCTURES OF RESIN STARTING MATERIALS BTDA = benzophenone tetracarboxylic acid dianhydride... 

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