可紫外光固化聚酰亚胺的设计制备及性能研究

以含酚羟基的2,2-双(3-氨基-4-羟基苯基)六氟丙烷(6FAP)作为接枝光敏单元的载体,以刚性苯并咪唑单元赋予材料良好的力学性能,设计合成了一种具有紫外光固化能力的可溶性聚酰亚胺.系统探究了光源距离、光源电流通量、光引发剂种类和含量、活性稀释剂种类等对固化成型过程的影响,确定了光固化聚酰亚胺的组成配方及工艺条件(光源距离为10 cm、电流通量为100%、双(2,4,6-三甲基苯甲酰基)-苯基氧化膦(Irgacure 819)含量为3 wt%、活性稀释剂1-乙烯基-2-吡咯烷酮(NVP)为20 wt%),并对光固化薄膜的基本性能进行了分析.光固化薄膜的拉伸强度达到123 MPa,固化树脂在5%(Td5)和10%(Td10)热失重时的温度分别为410和487℃,且具有较低的润湿性和吸水性.研究结果可为开发新型光敏性聚酰亚胺提供研究基础.

Chemical Structure Design,Preparation and Properties of UV Curable Polyimide

There is little literature on the development of photocurable polyimide materials and their curing process.Therefore,this paper focuses on the design and preparation of molecular structure of photocurable polyimides(PSPIs)and their composition formula and curing conditions.A soluble polyimide with a high UV curing ability was designed and synthesized by using 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane(6FAP)containing phenolic hydroxyl as the carrier of photosensitive unit and a rigid diamine with a benzimidazole unit to endow the material with good mechanical properties.FTIR and 1H-NMR tests proved the successful preparation of photosensitive polyimides with a maximum GMA content(photosensitive unit)of 51%.The solubility test results showed that the designed PSPIs had an excellent solubility in conventional polar solvents,which is beneficial to the processing of materials.The influences of light source distance,irradiation intensity,type and content of photoinitiator,and type of active diluent on the curing process were systematically investigated,and the composition and curing conditions were summarized(e.g.,the distance of the light source was 10 cm,the electric current was 100%,the Irgacure 819 content was 3 wt%,and the active diluent NVP was 20 wt%).The overall properties of photocured polyimide films were analyzed.The tensile strength of the film was up to 123 MPa,and the Td5 and Td10 reached 410 and 487℃,respectively.The mass residual rate at 800℃ is above 55%.Water contact angle of the cured PI film was up to 90.7°,and the water absorption rate was as low as 0.40 wt%,which indicated the excellent hydrophobicity of the cured PSPI film.Accordingly,the novel photocurable polyimides with excellent overall property developed in present work show great potential in microelectronics application.