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. POLYM. COMPOS., 39:E1800–E1806, 2018. © 2018 Society of Plastics Engineers