Study On The Fabrication And Properties Of Nano-TiO₂ /epoxy Resin Matrix Composites

In this paper, the properties of epoxy resin were modified by using nano-TiO₂. The nano-TiO₂/epoxy resin casting body and nano-TiO₂/carbon fiber/epoxy resin composite materials were prepared by the ultrasound dispersing technology. The effects of the nano- TiO₂ content, ultrasonic dispersion time and nanoparticle’s surface modifying ways by coupling agent on the properties of composite materials were studied. The dispersion of nano-TiO₂ in the epoxy resin was analyzed by using TEM, and the fracture morphology of resin casting bodies and nano-TiO₂/carbon fiber/epoxy resin composite materials were observed by SEM.The experimental results showed that the bending strength, bending modulus of elasticity, and impact strength of nano-TiO₂/epoxy resin casting body increased firstly and then decreased with the increasing of the content of nano-TiO₂. So did the change of the thermal deformation temperature of casting body. The TEM revealed that the more agglomeration of particles was occurred with the increase loading of nano-TiO₂ .The impact properties of epoxy resin casting body were influenced greatly by the different modifying method of nano-TiO₂ surface using titanate coupling agent. After nano-TiO₂ treated with coupling agent in isopropanol solvent, the best impact strength of casting body was obtained. When the nanoparticles were dealed with coupling agent in ethanol, the impact strength of casting body took the second place. And the worst one was observed by treating the nano-TiO₂ surface directly with the coupling agent. The SEM showed that the impact fracture of the casting body was the typical ductile one by treating the the nanoparticles surfaces with the coupling agent in isopropanol solvent. And the impact fracture of the casting body was smooth when the nano-TiO₂ was modified with coupling agent directly or using ethanol as solvent, the agglomeration of particles became seriously.The analysis results showed that interlaminar shear strength of nano-TiO₂/carbon fiber/epoxy resin composite material increased with the increaseing of the content of nanoparticles. After adding coupling agent, the interlaminar shear strength （ILSS） of composite materials increased apparently. The ILSS of composites increased firstly and then decreased with the increasing of the content of nanoparticles. The fracture morphology showed that interface bonding between the carbon fiber and epoxy resin was improved obviously by adding nanoparticles.