共聚与机械共混对PMDA／ODA型聚酰亚胺性能的影响

Effect of copolymerization and mechanical blending on performance of PMDA/ODA-polyimide

针对均苯四甲酸二酐/二氨基二苯醚(PMDA/ODA)型聚酰亚胺(PI)难以溶解或熔融、柔韧性较差,以1,3-双(4氨-基苯氧基)苯(BAPB134)、ODA和PMDA为原料,通过共缩聚和机械共混分别制备了一系列共聚聚酰亚胺(CoPI)和共混聚酰亚胺。采用IR、TGA、DSC、XRD和拉伸等手段,对其结构和性能进行了研究。结果表明,CoPI薄膜为非晶态结构,玻璃化转变温度和起始分解温度分别在322℃和544℃以上,断裂伸长率由12%平均提高到54%,拉伸强度均超过100 MPa,但弹性模量平均降低了29%;共混PI的聚集态结构和性能与PMDA/ODA型PI相近。

PMDA/ODA-polyimide can hardly be soluble or fusing and its flexibility is not good enough. To solve these shortages, a series of copolyimides （CoPI） and polyimide blends were prepared based on 1,3- bis （4-aminophenoxy） benzene （ BAPB 134 ）, 4,4＇ -diaminodephenyl ether （ODA） and pyromellitic dianhydride （PMDA）. Their structures and properties were characterized by means of IR, TGA, DSC, XRD and Tensile Tester. The results showed that CoPI films were amorphous state and their glass-transition temperatures （Ts ） and decomposition temperatures （Td） respectively occurred above 322 ℃ and 544 ℃. At the same time,the tensile strengths of CoPI films reached beyond 100 MPa and breaking elongations were improved from 12% to 54% ,but the average of tensile modulus was reduced by 29%. However, polyimide blends had about the same structures and properties with PMDA/ODA-polyimide.