Synthesis and characterization of high Tg and colorless polyamide-imide films derived from amide-containing diamines with different trifluoromethyl substitution
substitution position on poly(amide-imide)s (PAIs) properties. High-performance PAIs were prepared from high-temperature polycondensation of these diamines with 6FDA dianhydride. All the PAI films exhibited good heat resistance with glass-transition temperatures (s) of 311–392 °C, good 5% weight loss temperatures (s) of 480–510 °C in nitrogen, and excellent optical transparency with ranging from 52% to 84%. According
成功合成了四种新的二胺(3TFDABA、2TFDABA、22TFDABA 和 TFAPTA),以研究不同三氟甲基 (CF) 取代位置对聚酰胺酰亚胺 (PAI) 性能的影响。通过这些二胺与 6FDA 二酐的高温缩聚反应制备了高性能 PAI。所有 PAI 薄膜都表现出良好的耐热性,玻璃化转变温度 (s) 为 311–392 °C,在氮气中良好的 5% 失重温度 (s) 为 480–510 °C,并且具有优异的光学透明度,范围为 52%至 84%。根据单体结构设计,形成高耐热无色聚酰胺酰亚胺薄膜(PAI-2-6FDA),具有优异的光学性能(82%)、优异的热性能(499℃和392℃) C),并获得了良好的机械性能(拉伸强度为123 MPa,拉伸模量为4.4 GPa)。全面的结构与性能关系研究表明,氨基上的CF有效抑制了酰亚胺环与苯之间的旋转,从而提高了薄膜的耐热性。此外,它还可以通过强吸电子能力