纳米SiO_(2)@MWCNT增强氰酸酯基形状记忆复合材料的制备及性能

Preparation and Properties of Nano-SiO_(2)@MWCNT Reinforced Cyanate-Based Shape Memory Composites

形状记忆聚合物由于刚度、强度、回复驱动力等方面的限制,无法直接作为结构材料应用于航天航空。文中利用纳米二氧化硅包覆碳纳米管(SiO_(2)@MWCNT)改性的氰酸酯/聚丁二烯环氧树脂形状记忆树脂基体与T300碳纤维平纹织物通过热压成型法制备了一种形状记忆复合材料,系统表征和分析了形状记忆复合材料的力学性能、耐温性能和形状恢复能力。结果表明,在保证复合材料优异形状记忆效果的同时,以SiO_(2)@MWCNT作为增强纳米粒子显著提高了复合材料的玻璃化转变温度与力学性能。复合材料在玻璃化转变温度(212℃)附近仍保有1 GPa左右的储能模量,经过10次循环测试后,形状固定率和形状回复率都分别保持在96%和97%以上,并在35 s内完成由临时形状到初始形状的转变,展现出优异的回复速度与更大的形状回复力。

Shape memory polymers cannot be directly used as structural material in aerospace applications due to limitations in stiffness,strength and response drive.In this study,a shape memory composite was prepared by hot pressing method using nano-silica coated carbon nanotubes(SiO_(2)@MWCNT)modified cyanate ester/polybutadiene epoxy resin shape memory resin matrix and T300 carbon fiber plain fabric.The mechanical properties,temperature resistance and shape recovery ability of the shape memory composite were systematically characterized and analyzed.It is shown that the glass transition temperature and mechanical properties of the composite are significantly improved by using SiO_(2)@MWCNT as reinforced nanoparticles while ensuring the excellent shape memory effect of the composite.The composite still maintains a storage modulus of about 1 GPa near the glass transition temperature(212℃).After ten cycles of testing,the shape fixation rate and shape recovery rate are both maintained above 96%and 97%.Respectively,the transition from temporary shape to initial shape is completed within 35 s,showing excellent recovery speed and greater shape recovery force.