双酚A及端羧基丁腈橡胶对环氧树脂的增韧作用

Toughening of bisphenol A and carboxyl-terminated butadiene-acrylonitrile to epoxy resin

以2-乙基-4-甲基咪唑为固化剂,分别以端羧基丁腈橡胶(CTBN)、CTBN/双酚A(BPA)或BPA为增韧剂增韧环氧树脂,研究了环氧树脂增韧体系的微观形貌和力学性能,考察了不同混料方式对CTBN增韧环氧树脂性能的影响。结果表明:CTBN增韧环氧树脂能使其固化物的冲击韧性有所提高,但其他力学性能降低;采用环氧树脂先与其进行预聚反应再经固化剂固化的方法能提高CTBN对环氧树脂的增韧效果;用CTBN/BPA为增韧剂不仅可以大幅度提高材料的冲击强度和扯断伸长率,而且可以提高弯曲强度与模量,克服了CTBN单一增韧导致材料强度下降的不足。BPA的加入可使环氧树脂固化物体系的弯曲强度、冲击强度和扯断伸长率有较大幅度的提高。

The micromorphology and mechanical properties of epoxy resin modified with carboxyl-terminated butadiene-acrylonitrile copolymer （ CTBN ） , CTBN/bisphenol A （BPA） and BPA have been examined respectively. The effect of different CTBN adding modes on the mechanical properties of toughened epoxy resin has been studied. It was found that the toughness of epoxy resin increased toughened by CTBN while other mechanical properties declined. In the case of 120 ℃ pre-reacted with epoxy resin for 2 h, better CTBN toughening result could be achieved. When epoxy resin modified with CTBN/BPA, the impact strength and the elongation at break increased dramatically, as well as other mechanical properties enhanced to a certain extent, and it was overcome the disadvantages of CTBN toughened epoxy resin singly. The toughening agent of BPA could also increased flexural strength, impact strength and elongation at break of epoxy resin.