BTDA/PMDA-TDI/MDI四元共聚聚酰亚胺的制备和表征

The preparation and characterization on BTDA/PMDA-TDI/MDI quaternary co-polyimide

着重介绍了以N,N-二甲基乙酰胺(DMAc)为溶剂,利用3,3′,4,4′-二苯酮四酸二酐(BTDA)、均苯四甲酸二酐(PMDA)、甲苯二异氰酸酯(TDI)、4,4′-二苯基甲烷二异氰酸酯(MDI)四元体系(其中,TDI和MDI的摩尔比为80:20,BTDA和PMDA的摩尔比分别为95:5、90:10、85:15、80:20)合成聚酰亚胺(PI)的方法;并对聚合得到的产物的特性粘度、傅利叶转换红外光谱(FTIR)、核磁共振氢谱、热失重分析(TGA)等、力学性能等进行测试表征。结果表明:当BTDA:PMDA=95:5时特性粘度最大,为0.937 5 dL/g;在红外光谱中,波数为723 cm^(-1)、1364 cm^(-1)、1723cm^(-1)、1779 cm^(-1)处有酰亚胺的特征吸收峰;核磁共振氢谱图证实加入第四单体PMDA;TGA曲线及力学性能测试表明,聚合产物具有优良的耐热及较好的力学性能。

The preparation and application prospects are also introduced. The polyimide was prepared by benzophenone-3,3＇,4,4＇-tetracarboxylic acid dianhydride（BTDA）, 1,2,4,5-Benzenetetracarboxylic anhydride（PMDA） 4,4＇-methylenebis （phenyl isocyanate）（MDI）, and toluene diisocyanate（TDI） in the solvent of dimethylacetamide（DMAc）. Among it, the mole ratio of BTDA and PMDA were 95 ＂ 5, 90 ： 10, 85 ： 15, 80 ＂ 20, and the mole ratio of TDI and MDI was 80 ＂ 20. Then intrinsic viscosity, Fourier Transform infrared Spectrum（FTIR）, proton NMR spectra （1H NMR）, thermal gravimetric analysis（TGA） and mechanical property were operated. The maximum viscosity value of all samples was reached when the mole ratio was 95 ： 5. The FTIR spectrum showed that the peaks at 1 780 cm-1, 1 720 cm-l, 1 380cm-1, 725 cm-1 wavelength were the characteristic ones of imides. Proton NMR spectra（1H NMR） proves that PMDA was added. The TGA curves and mechanical test indicated that the quaternary co-polyimide has a good thermal stability and mechanical property.