聚(苯乙烯-alt-马来酸酐)修饰碳纳米管改性环氧树脂

Poly(styrene-alt-maleic anhydride) decorated carbon nanotube for modifying epoxy resin

通过聚(苯乙烯-alt-马来酸酐)(SMA)上的酸酐与氨基化碳纳米管(CNT)表面的氨基基团进行酰胺化反应修饰碳纳米管,得到SMA/CNT。然后将SMA/CNT作为改性剂加入双酚A型环氧树脂(E51)-甲基六氢苯酐(MHHPA)固化体系。通过红外光谱、热失重分析和扫描电镜对SMA/CNT进行了表征,采用示差扫描量热法(DSC)研究了SMA/CNT对E51-MHHPA体系固化行为的影响,并测试了E51/MHHPA/SMA/CNT体系固化物的力学性能、热机械性能和热稳定性。结果表明,利用SMA修饰CNT,在CNT表面引入了酸酐、羧酸反应基团,可参与环氧固化反应,增强了CNT与树脂基体的界面结合力,提高了固化物的交联密度,从而对固化物起到了同时增韧和增强的效果。此外,SMA/CNT改性的环氧热固化物的玻璃态储能模量、玻璃化转变温度及热稳定性也得到了显著改善。当SMA/CNT的添加质量分数为3%时,固化物的综合性能最优。

The carbon nanotubes were decorated by the amidation reaction of acid anhydride on poly(styrene-alt-maleic anhydride)(SMA)with amino group on the surface of an aminated carbon nanotube(CNT)to obtain SMA/CNT.The SMA/CNT was then added as a modifier to the bisphenol A epoxy resin(E51)-methylhexahydrophthalic anhydride(MHHPA)curing system.The SMA/CNT was characterized by infrared spectroscopy,thermal weight loss analysis,and scanning electron microscopy.The effect of SMA/CNT on the curing behavior of the E51-MHHPA system was studied by differential scanning calorimetry(DSC),and the mechanical properties,thermomechanical properties,and thermal stability of E51/MHHPA/SMA/CNT system were tested.The results showed that the acid anhydride and carboxylic acid reactive groups were introduced on the surface of CNTs by the modification of CNTs with SMA,which could participate in the epoxy curing reaction,enhance the interfacial bonding force between CNTs and the resin matrix,and improve the crosslink density of the cured product.Therefore,it had the effect of simultaneously toughening and strengthening the cured product.In addition,the glassy storage modulus,glass transition temperature and thermal stability of SMA/CNT-modified epoxy thermosets were also significantly improved.When the added mass fraction of SMA/CNT was 3%,the comprehensive properties of the cured product were optimal.