摘要
研究了"离位"增韧对RTM聚酰亚胺(PI-9731)树脂基复合材料力学性能的影响。结果表明:当增韧剂的质量分数为15%时,经粉末法和薄膜法"离位"增韧G827/PI-9731复合材料的室温层间剪切强度从增韧前的97.9 MPa分别提高到108 MPa和110 MPa,高温(288℃)层间剪切强度变化不大。G827/PI-9731复合材料经粉末法"离位"增韧后,Ⅰ型断裂能释放率从增韧前的310 J/m2提高到410 J/m2,Ⅱ型断裂能释放率从增韧前的590 J/m2提高到939 J/m2。而经过薄膜法"离位"增韧后,其复合材料的Ⅰ型断裂能释放率提高到459 J/m2,Ⅱ型断裂能释放率提高到1100 J/m2。经电镜分析表明,由于热塑性聚酰亚胺的引入,在复合材料层间区域形成热固/热塑相反转结构,在裂纹扩展的过程中,包覆热塑性聚酰亚胺的PI-9731粒子发生明显取向和变形,从而提高韧性。
The effect of ex-situ method on the mechanical properties and toughness of the RTMable carbon fiber（G827）/polyimide（PI-9731）composites was studied.The results show that the interlaminar shear strength of G827/PI-9731 composites toughened by the ex-situ methods with powder and film increases from 97.9MPa to 108MPa and 110MPa,respectively,when the thermoplastic PI mass fraction is 15% at room temperature.However,the interlaminar shear strength changes slightly at high temperature（288℃）.The mode Ⅰ fracture toughness of G827/PI-9731 composites toughened with powder method is improved from 310J/m2 to 410J/m2.The Mode Ⅱ fracture toughness is improved from 590J/m2 to 939J/m2.However the mode Ⅰ fracture toughness of G827/PI-9731 composites toughened with film method increases to 459J/m2.The mode Ⅱ fracture toughness is improved to 1100J/m2.By SEM analysis,it is found that the toughness improvement results from the introduction of thermoplastic PI and the formation of the TP/TS phase inversion structure in the interlaminar regions,in which the PI-9731 particles wrapped by thermoplastic PI will be orientated and deformed in the process of crack extension.
出处
《复合材料学报》
EI
CAS
CSCD
北大核心
2010年第6期1-8,共8页
Acta Materiae Compositae Sinica
基金
国家973项目(2010CB63110)
重点实验室基金(KZ42092823)
