迈克尔加成高效制备丙烯酸酯化光敏性聚酰亚胺

Highly Efficient Preparation of Acrylate Photosensitive Polyimide by Michael Addition

为克服传统光敏聚酰亚胺加工温度过高、成本高、介电性不佳、感光效率低、溶解性差等问题,利用多官能酸酐转化为多官能酰亚胺及酰亚胺对多官能丙烯酸酯的迈克尔加成反应,设计制备了10个光敏型丙烯酸酯化聚酰亚胺树脂(PI),并通过加入光引发剂进行自由基紫外光固化成膜。以核磁共振谱(NMR)、傅立叶变换红外光谱仪(FT-IR)对所得树脂PI结构进行了表征,通过FT-IR跟踪表征了PI光固化行为,并考察了活性稀释剂、光固化条件等对树脂固化行为的影响。再通过差示扫描量热仪(DSC)、热重分析仪(TG)以及介电谱和应力-应变测试等表征了聚酰亚胺丙烯酸酯固化膜的基本性能。结果表明:树脂光固化过程双键转化程度可达90%,树脂结构与固化膜性能之间存在一定关联,未添加稀释剂PI固化膜相对介电常数基本低于3.0,显著低于常规光固化丙烯酸酯单体,添加特种N-乙烯基环酰胺活性稀释剂可使PI介电性略有升高。

To overcome the existing problems of traditional photosensitive polyimide,such as high processing temperature,high cost,poor dielectric property,low photosensitive efficiency and poor solubility,ten photosensitive acrylate esterified polyimide resins(PI)were designed and prepared through converting polyfunctional anhydride to polyfunctional imide and the Michael addition reaction of imide to polyfunctional acrylic ester,and photoinitiator was introduced to realize free radical UV curing.The PI structure was characterized by NMR and FT-IR,the photocuring behavior of PI was tracked by FT-IR,and the effects of active diluent and photocuring conditions on the curing behavior were investigated.Then the basic properties of polyimide acrylate film were tested by DSC,TGA,dielectric spectrum and stressstrain test.The results showed that the double bond conversion degree could reach 90%in the photocuring process.The relative dielectric constant of the PI cured film without adding diluent was lower than 3.0,which was significantly lower than that of the conventional photocuring acrylate monomer.The dielectric constant slightly increased by adding specialty N-vinyl cyclamate reactive diluent.