酸化改性碳纳米管增韧双马树脂复合材料的研究

Research on cabon nanotube toughening bismaleimide resin composite

使用混酸对碳纳米管表面进行酸化改性,研究了酸化改性碳纳米管(MWCNTs-COOH)在丙酮中的分散稳定性。采用长时超声的方法将MWCNTs-COOH分散在双马树脂(BMI)体系中,制备了烯丙基双酚A改性双马树脂/酸化改性碳纳米管复合材料(BMI-DBA/MWCNTs-COOH)。通过场发射扫描电镜(FE-SEM)观察MWCNTsCOOH在复合材料中的分散性,研究了复合材料的机械性能、热机械性能和耐热性能。结果表明:与BMI相比,当加入0.2%(质量分数)MWCNTs-COOH时,复合材料的拉伸强度从61.9MPa提高到87.6MPa,提高了42%;弯曲强度从77.6MPa提高到102.9MPa,提高了33%;抗冲击强度从4.84kJ/cm^2提高到7.04kJ/cm^2,提高了约1.5倍。MWCNTs-COOH的引入可有效改善碳纳米管与树脂基体间的界面作用力,显著提高复合材料的模量和玻璃化转变温度(T_g);与BMI相比,加入MWCNTs-COOH的复合材料在N_2氛围下800℃的残炭率提高了约8%。

Carbon nanotubes were acidified by mixtural acid and the obtained acidified carbon nanotubes（MWCNTs-COOH）were dispersed in acetone which the dispersion stability was investigated.Allyl bisphenol A modified bismaleimide resin/acidified carbon nanotubes composite（BMI-DBA/MWCNTs-COOH）was prepared by dispersing acidified carbon nanotubes in bismaleimide resin（BMI）system which using long time sonication method.The dispersion of acidified carbon nanotubes in the composite was investigated by field emission scanning electronic microscope（FE-SEM）.The mechanical,thermo-mechanical and heat resistant properties of composite were studied.The results indicated that,comparing with the neat resin system,when 0.2 wt% acidified carbon nanotubes were added,the tensile strength of composite was increased by about 42% from around 61.9 MPa to 87.6 MPa.The flexural strength was increased from around 77.6 MPa to 102.9 MPa with an increment of 33%,and the impact strength was elevated up to 7.04 kJ/m2 which was about 1.5 times of 4.84 kJ/cm2 of neat resin.The addition of acidified carbon nanotubes could improve the interface interaction between carbon nanotubes and resin matrix efficiently,then improved the modulus and T_g of composite obviously.Also,comparing with neat resin,the char yield at 800 ℃ in nitrogen of composite with acidified carbon nanotubes was increased by about 8%.