摘要
从分子结构出发,设计合成了含酞/芴Cardo环结构、1,3,4-噁二唑不对称结构共计3类10种新型链延长型双马来酰亚胺(BMI),采用核磁共振(NMR)、红外光谱(IR)、示差扫描量热仪(DSC)、热失重分析仪(TGA)、动态力学分析仪(DMA)等技术表征了BMI树脂的化学结构、固化行为以及固化物的热稳定性和动态力学性能,探讨了分子结构与性能关系.研究结果表明含酞(芴)Cardo结构BMI在普通低沸点有机溶剂中具有良好的溶解性能;含1,3,4-噁二唑结构BMI由于具有不对称分子结构导致两端官能团反应活性存在明显差异;3类BMI的固化物均具有优异耐热性和热稳定性.
Three types of chain-extended bismaleimides with aromatic hetero-cycle structure（PBMI, FBMI, ZBMI） were synthesized, and their chemical structure and thermal properties were characterized by nuclear magnetic resonance（NMR） spectroscopy, infrared（IR） spectroscopy, differential scanning calorimeter（DSC）, thermo-gravimetric analyzer（TGA） and dynamic mechanical analyzer（DMA）, respectively. PBMI, a phthalide-containing bismaleimide, was prepared with phenolphthalein, o-cresolphthaleine and thymolphthalein as initial raw materials. With increasing number and volume of substituent groups, the solubility of PBMIs in common organic solvents was enhanced while their reactivity reduced. Three cured PBMI resins showed excellent thermal stability and heat resistance. Their glass transition temperatures（Tg） and the temperatures of 10% weight loss, both decreased with the number of alkyl chain substituents to aromatic rings, were in the range of 324 ？364 ℃ and 454 ？ 495 ℃, respectively. The cured PBMI with only methyl groups demonstrated an optimal moisture resistance. FBMI, a fluorene-containing bismaleimide, was subdivided into ether-type FBMI and ester-type FBMI. The melting point of the ether-type FBMI was lower than that of the ester-type FBMI, and the reactivity of the two resins were comparable with each other. The heat resistance and moisture resistance of the cured products of the former were superior to those of the latter. In addition, the incorporation of methyl groups into the molecular skeleton of the two types of FBMI resulted in a decrease of above-mentioned properties. The Tgvalues of the four FBMI cured products were all above 350 ℃ and the maximal Tg value reached above 400 ℃. ZBMI, a 1,3,4-oxadiazole-containing bismaleimide with asymmetric molecular structure, was designed and synthesized based on the characteristics of synthetic process of 1,3,4-oxadiazole moiety. Three ZBMI monomers exhibited good solubility and different reactivity of two end-capped unsaturated double bonds. Their cured products with fully aromatic heterocyclic structure were characterized by higher thermal stability and the initial decomposition temperature of 500 ℃.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
2017年第3期399-410,共12页
Acta Polymerica Sinica
基金
国防基础科研重点项目(项目号A3520110001)
国家自然科学基金(基金号51303107)
辽宁省重点科技攻关项目(项目号2007403009)
辽宁省高等学校优秀人才支持计划项目(项目号LR2013002)
辽宁省教育厅基础研究项目(项目号LZ2015057
LZ2015058)资助
