【摘要】 以改进的PMR方法由联苯四甲酸二甲酯(BPDE),二氨基二苯甲烷(MDA)及降冰片烯二酸单甲酯(NE)合成的树脂为基体制备了AS4碳纤维增强的超高温聚酰亚胺复合材料。研究了树脂预聚物的高温流变行为。制得的复合材料在室温的弯曲强度为1190MPa,弯曲模量为121GPa,层间剪切强度为42MPa;在371℃的力学性能分别是763MPa、116GPa、26MPa;在371℃时的力学强度保持率可达50%以上;玻璃化温度为472℃;该基体树脂和复合材料在空气中371℃下100h老化后,热失重分别为1.9%和2%。更多还原

【Abstract】 The ultrahigh temperature composite was fabricated based on polyimide containing biphenyl structure as the matrix resin and carbon fiber AS4. The rheology of polyimide precursor prepared by a modified polymerization of monomeric reactants approach (MPMR) was studied. The flexural strength and flexural modulus of the composite at RT and 371℃ are 1190 MPa,763 MPa and 121 GPa, 116 GPa, respectively. The shear strength of the composite at RT and 371℃ are 42 MPa and 26 MPa. The mechanical property of the composite can reach half of its mechanical property at room temperature. The glass transition temperature is up to 472℃ by DMA. The weight losses of the resin and composite at 371℃ for 100 h are 1.9 % and 2.0 %.更多还原