纳米SiO_2增韧改性环氧乙烯基酯树脂的性能研究

Study on the Properties of Epoxy Vinyl Ester Resin Toughened and Modified by Nano-SiO_2

为了对环氧乙烯基酯树脂(EVER)进行增韧改性,采用KH570硅烷偶联剂对纳米SiO2进行表面处理,考察了纳米SiO2表面改性及其质量分数对EVER力学性能的影响。经过偶联剂处理的纳米SiO2复合材料在树脂基体中具备更好的分散性和相容性,力学性能明显优于纯EVER材料和未经偶联剂处理的复合材料。纳米SiO2质量分数为3%时,纳米SiO2复合材料的拉伸强度、断裂伸长率、冲击强度分别比纯EVER材料提高了42.10%,43.38%和91.91%;纳米SiO2质量分数为4%时,纳米SiO2复合材料的拉伸模量比纯EVER材料提高了34.57%。通过观察冲击断面的SEM照片,分析了纳米SiO2增韧改性的作用机理。结果表明:纳米SiO2增韧改性的关键在于诱发基体产生银纹,使其对裂纹扩展起到钝化、阻碍的作用。

Nano.SiO2 were surface modified with KH570 silane coupling agent in order to toughen the epoxy vinyl ester resin（EVER）,surface modification and contents of nano-SiO2 on the mechanical properties of EVER composites were investigated. Disperse and compatible properties of the nano-SiO2 in EVER are improved after modified with silane coupling agent,mechanics performance obviously surpasses than that of pure EVER and composites without silane coupling agent. At 3% nano-SiO2 content,the tensile strength,elongation at break and impact strength are increased by 42.10%,43.38% and 91.91%,respectively;when the nano-SiO2 is added 4%,the elastic modulus is increased by 34.57%. Scanning electron microscopies（SEM）is applied to analyze the toughening mechanism of nano-SiO2. The results show that the key of toughening modification by nano-SiO2 is induced the matrix production ilver streak and its passivation and blocking to the rack development.