含苯乙炔基的酰亚胺低聚物及其复合材料研究

Study on imide oligomers containing pendent phenylethynyl group and their composite

制备了一种侧链含苯乙炔基的二胺单体2,4-二氨基[4'-(4-苯乙炔基酞酰亚胺基)]二苯醚(DPED),并合成了基于2,3',3,4'-联苯四甲酸二酐(3,4'-BPDA)和DPED的酰亚胺低聚物,通过热重分析,示差扫描量热分析,1H NMR,熔点和力学性能测试研究了DPED的结构及固化行为,低聚物和其固化物及其碳纤维增强复合材料的性能。结果表明:在主链化学结构相同的情况下,将DPED引入到分子质量约为5 000 g/mol的低聚物中,低聚物熔体粘度会有显著降低,侧链苯乙炔基含量越高,其熔体粘度越低,含侧链苯乙炔基的树脂基复合材料的压缩强度高于不含侧链苯乙炔基复合材料,其值分别为570 MPa和415 MPa。

The 2, 4 - diamino [ 4＇ - （4 - phenylethynyl phthalimide） ] diphenyl ether （ DPED）, a diamine containing pendent phenylethynyl group was synthesized and the imide oligomers based on 2, 3＇, 3, 4＇ -biphenyl tetracarboxylic dianhydride （3, 4＇ - BPDA） and DPED were prapared . The structure and curing behavior of DPED and performance of imide oligomers, their cured products and carbon fiber reinforced composites were investigated by thermogravimetric analysis, differential scanning calorimetry thermal analysis, 1H NMR, melting point test and mechanical property testings. The results showed that the melt viscosity would be significantly decreased by the introduction of DPED into the oligomer with molecular weight about 5 000 g/mol in the case of the oligomers with same chemical structure in the main chain, the higher the content of pendent phenylethynyl, the lower melt viscosity. The compressive strength of composite based on imide oligomers with pendent phenylethynyl group was higher than that of without pendent phenylethynyl group ones and the values were 570 MPa and 415 MPa, respectively.