Preparation and mechanical properties of nano-silica/UPR polymer composite

Abstract

Abstract This article mainly aims at experiments used for modifying unsaturated polyester resin (UPR), and trying to enhance the strengthening and toughening performance of nano-silica/UPR polymer composite in order to improve its integrated mechanical properties and to expand its field of application. Experiments were initially used to get high dispersibility nano-silica powder by adding silane coupling agent KH570 as a dispersant into commonly and commercially available nano-silica powder. Then, high dispersibility nano-silica powder was added as a filling with different mass fraction ratios into UPR and nano-silica/UPR polymer composite samples were fabricated. Infrared spectroscopy analysis, X-ray diffraction analysis, and scanning electron microscopy (SEM) analysis were conducted for high dispersibility nano-silica powder. Mechanical properties test and SEM observation of fracture morphology were investigated for nano-silica/UPR polymer composite samples. The results revealed that adding silane coupling agent KH570 with a mass fraction ratio 3% into nano-silica powder made nano-silica best dispersed after the modification reaction at a temperature of 80°C for 2 h. When the high dispersibility nano-silica powder was added into UPR with a mass fraction ratio 1.5%, the impact strength of nano-silica/UPR polymer composite improved greatly by 9.6%. However, when the high dispersibility nano-silica powder was added into UPR with a mass fraction ratio 2%, the tensile strength, bending strength and extension rate of nano-silica/UPR polymer composite improved greatly by 152%, 102%, and 167%, respectively.