剑麻纤维/纳米酚醛树脂复合材料的动态力学性能和热性能

Dynamic Mechanical and Thermal Properties of Sisal Fiber/Nanometer-Particles Phenol Formaldehyde Resin Composites

分别采用碱、硅烷偶联剂(KH-550)对剑麻纤维(SF)进行表面处理,选用无机纳米SiO2改性的酚醛树脂(PF)作为基体树脂,通过模压成型工艺制备剑麻纤维/纳米酚醛树脂复合材料。分别采用动态力学分析(DMA)、热重分析(TG)研究纳米SiO2的加入及剑麻纤维处理方式对SF/PF复合材料动态力学、蠕变、应力松弛性和热性能的影响。结果表明,与未添加纳米SiO2的SF/PF复合材料相比,SF/纳米PF复合材料的储能模量达到4783MPa,提高了46.8%;与未改性SF/纳米PF复合材料相比,经过碱处理的SF/纳米PF复合材料玻璃化转变温度(Tg)达到261℃,提高了14℃;热失重研究结果表明,纳米SiO2的加入及剑麻纤维改性均能显著提高SF/PF复合材料的热分解温度。

In this work,sisal fiber（SF） was pretreated by alkali,silane coupling agent KH-550 respectively. The phenol formaldehyde（PF） resin modified by nano-particles was used to prepared the composites through compression molding. The dynamic mechanical properties,creep and stress relaxation behavior were studied by DMA. The thermal properties of the SF/PF composites were studied by thermo gravimetric analysis （TG）. Results indicate that the storage modulus of the SF/PF composites modified by nano-particles reaches 4783 MPa,which increases by 46.8% compared to the pure SF/PF composites,the glass transition temperature of SF/PF composites treated with alkali is 261 ℃,which is 14 ℃ higher than the untreated fiber composites. The behaviors of the stress relaxation and creep are improved significantly due to the addition of nano-paticles and the treatment of sisal fiber. The result of the TG also shows that the nano-paticles can improve thermal stability of the composites. Furthermore,the treated sisal fiber shows better fiber–matrix bonding,so the thermal stability of the SF/PF can be increased.