BTDA-DATA

The incorporation of pyridine or triazole improves the adhesion between poly(imide)s and copper.Poly(3,3, 4,4 -benzophenone tetracarboxylic dianhydride-3,5-diamino-l,2,4-triazole) (BTDA-DATA) contains the triazole moiety as repeating units. Poly(4,4 -oxydiphthalic anhydride-1,3-aminophenoxybenzene-8-azaadenine) (ODPA-APB-8-AA) bears the triazole moieties at the end." BTDA-DATA starts to decompose at 350°C. However, ODPA-APB-8-AA starts to decompose at 400°C. The polymers have been tested as adhesives for copper surfaces. The adhesion is increased by the formation of copper complexes. 

This observation is further dramatized by some rather limited isothermal measurements on selected films (TABLE III). This data is typical of the metal ion filled BTDA + p,p -DABP poly-imides which we have examined. No changes in chemical functionality in the polyimide-metal film were apparent as judged by infrared spectral comparisons of polyimide alone and polyimide plus metal regardless of the metal employed. 

Resistivity Data on BTDA-m,m -DABP Polyimide Films3... 

Figure 3. Comparison of differential scanning calorimetric data (parts A and B) with thermomechanical analysis data (part C) for a cobalt chloride modified BTDA-ODA polyimide film.

The results given above indicate that, despite some variations in rate, anhydride end groups can all be classed as quite readily hydrolyzed. In contrast, the hydrolytic susceptibility of imide linkages varies much more with the polymer examined. BPDA-PDA showed no measurable imide hydrolysis whatsoever. In PMDA-ODA the amount of hydrolysis observed was small enough that we cannot eliminate the possibility that impurities in the anhydride component, rather than PMDA itself, resulted in the formation of hydrolyzable material. Of the polymers studied here, only those that contained BTDA as the anhydride component showed a marked susceptibility to imide hydrolysis. Even in this case, the data suggest that the reaction is limited in that only about 6-7% of the imide linkages appear to be susceptible to hydrolysis. 

The effect of the presence of water in the solvent on the stability of the resin solution is listed in Table I. The degradation rate for BTDA-p,p -DABP increases by a factor of three in the presence of 1.0 vol % water. The BTDA-ra,ra -DABP data indicate that the degradation rate kp0/Mo depends linearly on the water concentration. The slope of the three-point line is 7.5 X 10"6. The intercept kp0/M0(anhydrous) is. 031 X 10 4 days"1 in agreement with the nearly anhydrous kp0/M0(H2O <. 05% ) value of. 032 X 10 4 days"1. 

CBZ-PMDA), carbazole-1,4,5,8-naphthalene tetracar-boxylic dianhydride (CBZ-NTDA) and carbazole-benzophenone tetracarboxyl dianhydride (CBZ-BTDA) were synthesized by a similar method. Poly(N-vinyl-carbazole)-anhydride co-polycondensates such as PNVC-PhAn, PNVC-TMA, PNVC-PMDA, PNVC-NTDA and PNVC-BTDA were also prepared. Thermal stability characteristics of the various polycondensates have been compared in Table 16.18 and it was observed that (i) the initial decomposition temperature and the overall stability of a co-polycondensate of either CBZ or PNVC depends upon the anhydride moiety in the order of NDTA > BTDA > PMDA >TMA > PhAn (ii) initial decomposition temperature and the overall stability of a co-polycondensate with a fixed anhydride, vary in the order PNVC > CBZ and (iii) polycondensation of PNVC by anhydrides improves the thermal stability of the base polymer. It is suggested that the incorporation of thermally stable moieties, cross-links and rigidity is the main reason for enhanced initial decomposition temperature as well as overall thermal stability of these co-polycondensates. Table 16.19 gives the isothermal degradation stability of pairs of polycondensates and data confirm the high thermal stability... 

To improve the thermal stability of these polymers, Biswas and Mitra [349] prepared copolycondensates of carbazole (CBZ) with phthalic anhydride (PtiAn), trimellitic anhydride (TMA), pyromellitic dianhydride (PMDA), 1,4,5,8-naphthalene tetracar-boxylic dianhydride (NTDA), and benzophenone tetracarboxy dianhydride (BTDA) along with similar copolycondensates of PNVC. The thermal stabihty of copolycondensates was observed to depend on anhydride moiety in the order NDTA > BTDA > PMDA > TMA > PhAn for both the types of materials as given in Table IX. Table X shows the isotherm degradation stability of pairs of polycondensates, and the data confirm the high thermal stability of NTDA over the other materials. 

The precursors selected were Kapton, Matrimid, a phenolic resin, PVD-PVDC, PFA, and polyimide P84. Two laboratory-synthesized polyimides were also chosen for comparison, BTDA-ODA and 6FDA BPDA-DAM. Figure 23.7 compares the performance of some of these CMS membranes to that of polymer membranes listed in the literature for O2/N2 separation. The polymer data and the upper bound were obtained from Robeson (1991). The results show that almost all of the CMS membranes discussed here have properties above the polymeric upper bound. The best separation performance, in comparison to the polymer upper bound were from the CMS membranes produced from PFA and the polyimides Kapton, BTDA-ODA, and 6FDA BPDA-DAM. 

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