玻璃纤维增强乙烯基酯复合材料的层间增韧研究

Study on Interlaminar Toughening of Glass Fiber Reinforced Vinyl Ester Composite

为改善玻璃纤维/乙烯基酯树脂复合材料韧性差的缺点,采用端羧基丁腈橡胶(CTBN)和硫酸钙晶须(CSW)改性乙烯基酯树脂,以固化剂为胶液,无碱玻璃纤维布为增强体,制备了乙烯基酯树脂片状模塑料(VE SMC)。分别测试了CTBN、CSW协同CTBN改性复合材料的力学性能。结果表明:相比CTBN单独增韧VE SMC,CSW协同CTBN能够进一步提高复合材料力学性能。当CSW和CTBN含量分别为20份和9份时,复合材料拉伸强度、GⅡC和层间剪切强度分别为642 MPa、1.774 7 kJ/m2和38.6 MPa。与未增韧的VE SMC材料相比,分别提高了32.4%、43.6%和79.5%。同时复合材料玻璃化温度也从124.8℃上升至128.5℃。通过SEM测试发现,CSW协同CTBN增韧机制,与裂纹扩展过程中的屈服变形以及晶须桥联、裂纹偏转有关。

In order to improve the poor fracture toughness of glass fiber/vinyl ester resin composites,the vinyl ester resin sheet molding compounds(VE SMC) were manufactured using carboxy-terminated nitrile rubber(CTBN) and calcium sulfate whiskers(CSW) modified vinyl resin and E-glass fiber as reinforcement.The mechanical properties of composites modified by CTBN and CSW synergistic CTBN were tested respectively.The results show that compare with the composites modified only by CTBN,the property of composites toughening by CTBW synergistic with CTBN shows increasing tendency.When the content of CSW and CTBN are 20 phr and 9 phr,respectively,the tensile strength,GIICand interlaminar shear strength of VE SMC composites are 642 MPa,1.7747 k J/m2and 38.6 MPa,compared with the nontoughened VE SMC composites,which are increased by 32.4%,43.6% and 79.5% correspondingly.Furthermore,the glass transition temperature increases from 124.8 ℃ to 128.5 ℃.Through the observation of scanning electron microscope(SEM),it can be obtained that the toughening mechanism of CSW synergistically with CTBN is related to the yield deformation,whisker bridging and crack deflection in the process of crack propagation.