聚酰亚胺改性C/C复合材料的制备及性能  

Preparation and properties of polyimide modified C/C composites

作　　者：耿真真 李红[1] 杨敏[1] 任慕苏[1] 孙晋良[1] GENG Zhenzhen;LI Hong;YANG Min;REN Musu;SUN Jinliang(Research Center for Composite Materials,Shanghai University,Shanghai 200072,China)

机构地区：[1]上海大学复合材料研究中心,上海200072

出　　处：《复合材料学报》2019年第1期186-191,共6页Acta Materiae Compositae Sinica

基　　金：国家重点研发计划(2016YFE0111200)

摘　　要：采用针刺成型、化学气相渗透(CVI)、真空浸渍及固化成型工艺制备了C/C-聚酰亚胺(C/C-PI)复合材料,研究了这种新型防热结构材料的弯曲性能、导热性能及热膨胀性能。结果表明:C/C-PI复合材料XY向和Z向弯曲强度分别为120.75MPa和40.33MPa,较C/C复合材料分别提高了17.92%和20.57%,表现出更优异的弯曲性能;C/C-PI复合材料热导率随温度变化不显著,XY向和Z向热导率均在150℃达到最大值,分别为29.88W(m·℃)-1和9.93W(m·℃)-1,较C/C复合材料分别降低了47.02%和56.12%;随温度升高,C/C-PI复合材料的线膨胀系数呈线性缓慢增长,数值保持低于4×10-6 K-1,尤其XY向较Z向具有更低的线膨胀系数,可满足热结构件尺寸稳定性的使用需求。Polyimide modified C/C(C/C-PI)composites were fabricated by needling technology,chemical vapor infiltration(CVI),vacuum impregnation and curing process.The flexural properties,heat conducting properties and thermal expansion properties of C/C-PI composites were investigated.The results indicate that C/C-PI composites show a better flexural strength of 120.75 MPa in XYdirection and 40.33 MPa in Zdirection which are17.92% and 20.57% higher than C/C composite.The thermal conductivities of C/C-PI composites do not change significantly with temperature,and reach the maximum values of 29.88 W(m·℃)-1 in XY direction and9.93 W(m·℃)-1 in Zdirection,which are 47.02% and 56.12%lower than C/C composites,respectively.As the test temperature continues to rise,the thermal conductivities of C/C-PI and C/C composites are decreasing gradually.The coefficients of linear expansion of C/C-PI composites increase linearly with the increase of temperature and the values maintain under 4×10-6 K-1.In particularly,C/C-PI composites have a lower linear expansion coefficient in XYdirection in comparison with Zdirection,which can meet the requirement of dimension stability of thermal structure parts.

关 键 词：聚酰亚胺 C/C 弯曲强度 热导率 线膨胀系数 

分 类 号：TB332[一般工业技术—材料科学与工程]