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通过分子设计合成了一种含叔丁基、醚键和双酚A单元的二胺单体2,2-二(3’-叔丁基-4’-氨基二苯醚-4-基)丙烷(4),然后将其与4种商品化的芳香二酐单体:联苯四羧酸二酐(BPDA)、二苯醚四酸二酐(OPDA)、二苯六氟异丙基四酸二酐(6FDA)和均苯四酸二酐(PMDA)经高温“一步法”制备了一系列新型聚酰亚胺(PI)树脂,并对它们的结构与性能进行了研究.结果表明,该系列PI在NMP、DMF、DMAc、THF和CHCl3等普通有机溶剂中具有良好的溶解性;玻璃化转变温度Tg(DSC)在265~302℃之间,5%热失重温度(N2氛围)在519℃以上;在400~760 nm可见光波长范围内,具有优异的光学透明性,透光率约等于或大于90%;PI的数均分子量(Mn,GPC)在1.90×10~4~3.90×10~4范围内,分子量分布(PDI)介于2.63~4.63之间,X-射线衍射(XRD)结果表明所得PI为无定形聚合物,吸水率低于0.5%.叔丁基、醚键和双酚A单元同时引入具有协同效应,可提高PI的溶解性和透明性,并保持PI原有良好的热稳定性、机械性能和较低的吸水率.
A kind of diamine monomer 2,2-bis (3’-tert-butyl-4’-aminodiphenyl ether-4-yl) propane containing tert-butyl, ether and bisphenol A units was synthesized by molecular design (4), and then mixed with four commercially available aromatic dianhydride monomers: biphenyl tetracarboxylic dianhydride (BPDA), diphenyl ether tetra acid dianhydride (OPDA), diphenyl hexafluoroisopropyl tetracarboxylic acid A series of new polyimide (PI) resins were prepared by high-temperature “one-step ” method using dianhydride (6FDA) and pyromellitic dianhydride (PMDA), and their structures and properties were studied. , The series of PI has good solubility in common organic solvents such as NMP, DMF, DMAc, THF and CHCl3. The glass transition temperature Tg (DSC) is between 265 ℃ and 302 ℃, and the 5% weight loss temperature (N2 atmosphere) At 519 ℃ or above; excellent optical transparency in the visible light wavelength range of 400-760 nm, the light transmittance is about 90% or more; the number average molecular weight (Mn, GPC) of PI is between 1.90 × 10 -4 ~ 3.90 × 10-4, the molecular weight distribution (PDI) ranged from 2.63 to 4.63. The X-ray diffraction (XRD) results showed that the obtained PI was an amorphous polymer and the water absorption was less than 0.5% The simultaneous introduction of bisphenol A unit has a synergistic effect, which can improve the dissolution of PI And transparency, and to maintain the original PI good thermal stability, mechanical properties and low water absorption.