Castor Oil-Based Polyurethane/Silica Nanocomposites: Morphology, Thermal and Mechanical Properties

As a reinforcing filler, nano-silica was modified using silane coupling agents (KH560 and KH570). The effects of nano-silica loadings on the morphology, mechanical and thermal properties of castor oil-based PU nanocomposites were studied. Scanning electron microscopy demonstrated the relatively homogeneous dispersion of nano-silica in the PU matrix. After the addition of different nano-silica, a significant nano-silica reinforcement effect on castor oil-based PU matrix was found. The tensile strength and Young's modulus of the PU nanocomposites were increased with the increment of different nano-silica content. When compared with neat PU, PU/silica nanocomposites with 12 wt% SiO2, KH560-SiO2 and KH570-SiO2 loading exhibited 222, 230, and 87% improvement in tensile strength, and 182, 182, and 88% increment in Young's modulus, respectively. Furthermore, the thermal stability of PU nanocomposites was slightly improved with the incorporation of KH570-SiO2. At 12% SiO2, KH560-SiO2, and KH570-SiO2 loading, the residue of PU nanocomposites at 600 C were increased from 3.4 to 12.7, 13.1, and 10.6%, respectively. (C) 2018 Society of Plastics Engineers