多壁碳纳米管/聚醚砜环氧树脂复合材料的制备及力学性能

环氧树脂具有优异的热性能及力学性能，但本身脆性较大。为制备低成本、高性能的环氧树脂体系，使用聚醚砜（PES）和多壁碳纳米管（MWCNT）对环氧树脂进行增韧，制备了不同PES含量的PES-环氧树脂共混物，讨论了PES含量对环氧树脂力学性能的影响；采用熔融法，并配合使用机械搅拌、高剪切分散和超声分散制备了MWCNT/PES-环氧树脂复合材料，测试了其拉伸性能及断裂韧性，用SEM观察了MWCNT在树脂中的分散状态以及拉伸试样的断口形貌。结果表明：MWCNT的加入能够提高PES-环氧树脂体系的综合力学性能，且当MWCNT含量为0.7wt%时，树脂体系的综合力学性能最好；低PES含量下，小于1.0wt%的MWCNT的加入使材料力学性能超过用20.0wt%PES改性的环氧树脂；PES与MWCNT对环氧树脂具有协同增韧作用。

Preparation and mechanical properties of multi-walled carbon nanotubes/polyethersulphone epoxy composites

Epoxy has excellent thermal and mechanical properties, but is brittle. Polyethersulphone(PES) and multi-walled carbon nanotubes(MWCNT) were used to toughen epoxy for the preparation of low cost and high performance epoxy system. PES-epoxy blends of different PES contents were prepared and the influence of PES content on mechanical properties of epoxy was discussed. MWCNT/PES-epoxy composites were prepared by using melting method with mechanical agitatioin, high-shearing agitation and ultrasonic dispersion. The tensile properties and fracture toughness were tested. Both the dispersion of MWCNT in resin and the fracture surfaces of broken specimens were observed by SEM. The results show that the comprehensive mechanical properties of PES-epoxy composites can be further improved by adding MWCNT and arrive at the highest value when the MWCNT content is 0.7wt%. At low PES content, the mechanical properties of epoxy with MWCNT content less than 1.0wt% can exceed that of epoxy with 20.0wt% PES. PES and MWCNT have synergistic toughening effects on epoxy.