An alicyclic acid anhydride BOTA, containing four stereoisomers, racemic (1S,2R,3R,4R,5R)‐bicyclo[2.2.2]octane‐2,3,5‐tricarboxylic acid‐2,3‐anhydride (7a+7a’) and racemic (1S,2S,3S,4R,5R)‐bicyclo[2.2.2]octane‐2,3,5‐tricarboxylic acid‐2,3‐anhydride (7b+7b’), was synthesized using phthalic anhydride as the starting material. The chemical structures of the products in each step were fully characterized by NMR spectroscopy, GC‐MS, elemental analysis, and single‐crystal X‐ray diffraction. The polycondensation process involving BOTA and several diisocyanates was applied to prepare PAIs. Furthermore, PAI‐Xs were prepared using methylene diphenyl diisocyanate (MDI) and various mole ratios of BOTA and 4,4'‐(hexafluoroisopropylidene)diphthalic anhydride (6FDA). PAI‐Xs exhibited good solubility in organic solvents such as DMSO, NMP, DMAc, GBL, DMF, and m‐cresol at room temperature. They can form flexible films with low coefficients of thermal expansion (CTE) (51‐70 ppm/°C) and high glass transition temperatures (Tg) (222‐272 °C). They also demonstrated high transparency with transmittance at 500 nm (T500nm) ranging from 77.2‐82.5%. BOTA can be a significant building block in PAI synthesis, offering an alternative to trimellitic anhydride (TMA).This article is protected by copyright. All rights reserved

中文翻译：

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含有四种立体异构体的脂环酸酐及其衍生的二异氰酸酯聚酰胺酰亚胺的合成和表征

一种脂环酸酐BOTA，含有四种立体异构体，外消旋（1S,2右,3右,4右,5右)-双环[2.2.2]辛烷-2,3,5-三羧酸-2,3-酸酐(7a+7a')和外消旋(1S,2S,3S,4右,5右以邻苯二甲酸酐为原料合成了)-双环[2.2.2]辛烷-2,3,5-三羧酸-2,3-酸酐(7b+7b')。每个步骤中产物的化学结构均通过核磁共振波谱、GC-MS、元素分析和单晶 X 射线衍射进行了充分表征。采用 BOTA 和几种二异氰酸酯的缩聚工艺来制备 PAI。此外，使用亚甲基二苯基二异氰酸酯（MDI）和不同摩尔比的BOTA和4,4'-（六氟异亚丙基）二邻苯二甲酸酐（6FDA）制备PAI-X。 PAI-Xs 在 DMSO、NMP、DMAc、GBL、DMF 等有机溶剂中表现出良好的溶解度米室温下-甲酚。它们可以形成具有低热膨胀系数 (CTE) (51-70 ppm/°C) 和高玻璃化转变温度 (Tg) (222-272 °C) 的柔性薄膜。它们还表现出高透明度，500 nm (T500nm) 的透射率范围为 77.2‐82.5%。 BOTA 可以成为 PAI 合成中的重要组成部分，提供偏苯三酸酐 (TMA) 的替代品。本文受版权保护。版权所有