共缩聚型可溶性聚酰亚胺的微波辐射合成

以均苯四甲酸酐(PMDA)、3,3′,4,4′-二苯酮四羧酸二酐(BTDA)和甲苯2,4-二异氰酸酯(TDI)为单体,微波辐射低温溶液聚合生成一种共缩聚聚酰亚胺(PI).通过特性黏度(η])、红外光谱(FT-IR)、热失重分析(TGA)和X衍射分析(XRD)等对聚合物进行了一系列的结构表征和性能测试.结果表明,微波辐射溶液聚合能够提高PI的特性黏数及产率,微波的引入大大缩短了反应时间;FT-IR表明,在1779cm-1和1726cm-1处观察到聚酰亚胺特征峰;TGA表明,PI在氮气中520℃左右开始降解,10%热失重温度为585℃;溶解性测试表明,PI可以溶解在强极性非质子溶剂中,如DMF,DMSO,DMAc及NMP等,甚至部分溶解在THF中.

Synthesis of Soluble co-Condensation Type Polyimide by Microwave Irradiation

The co-polycondensation type polyimide (PI) was synthesized using 2,4-toluylene diisocyanate (TDI), 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BDTA) and pyromellitic acid dianhydride (PMDA) as monomers under microwave irradiation for polycondensation. The structure and performance of the polymer were characterized by inherent viscosity (η]), fourier transform infrared (FT-IR), thermogravimetric curve (TG) analyses, X-ray diffraction (XRD) and solubility tests. The results showed that under microwave irradiaton, the intrinsic viscosity and the yield of PI were raised, and the reaction time was shortened. The FT-IR spectra of the polymer shown that, there were PI′s characteristic peaks around 1 779 cm-1 and 1 726 cm-1. Thermogravimetric curve indicated that the obtained polyimide began to lose weight at 520 ℃ and its 10 % thermal decomposition temperature under N2 was 585 ℃. PI was soluble in most of polar aprotic solvents such as N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidinone (NMP) and even in tetrahydrofuran (THF).