含硫醚结构均苯型聚酰亚胺的合成及表征

以4,4′-二氨基二苯硫醚(SDA)和均苯四酸酐(PMDA)为原料,通过溶液缩聚法-热酰亚胺/化学酰亚胺化的方法制备了一种含硫醚结构均苯型聚酰亚胺.利用高级旋转流变仪建立了在线跟踪反应进程的方法,采用热失重分析仪研究反应条件对热酰亚胺化及化学酰亚胺化法的影响,这些方法的建立为进一步制备高性能的聚酰亚胺提供有效的实验手段.采用小角激光光散射法、红外光谱、元素分析、接触角仪、DSC等方法对聚合物的结构与性能进行表征.结果显示,硫醚结构的引入,可有效改善聚合物薄膜的表面性能,其与铜箔之间的粘附功明显大于传统聚酰亚胺,在无胶挠性线路板应用方面显示出较好的应用前景.所获聚合物的Mw为(6.7±1.6)×104,分解温度均高于560℃;DSC的结果显示所制备的两种酰亚胺化聚合物均具有较高的玻璃化转变温度,相比之下,化学酰亚胺化更有利于获得高酰亚胺化程度的聚合物,产物的玻璃化转变温度也更高.

SYNTHESIS AND CHARACTERIZATION OF POLYIMIDE WITH ARYLENE SULFIDE STRUCTURE

A polyimide with arylene sulphide structure units was synthesized via polycondensation of 4,4′- diamino diphenyl sulphide (SDA) and pyromellitic dianhydrid (PMDA) followed by thermal imidization and chemical imidization. A real-time online tracing method was built up by using the advanced rheology expanded systems (ARES) to monitor the polycondensation,and the effects of reaction conditions on the thermal and chemical imidization were studied by thermogravimetic analysis. The structures and properties of the polyimide were characterized by fourier transform infrared spectroscopy ( FTIR ),small angle laser light scattering (SALS),contact angle analysis and differential scanning calorimetry (DSC) etc. Results show that the surface properties of polyimide films are great improved by introducing the arylene sulphide structure into the main chain of polyimide,and the adhesion work between the new polyimide and copper foil is higher than the traditional one. The weight-average molecular weight of the polyimide is (6. 7 ± 1. 6) × 104; the decomposition temperature is higher than 560℃ ; DSC results show that the polyimides prepared by both thermal and chemical imidization have high glass transition temperature,and in comparison,chemical imidization gives rise to a higher degree of imidization and a higher glass transition temperature.