The physical properties of polyurethane (PU) reinforced with surface modified halloysite nanotubes (HNTs) were investigated. The HNTs were modified with two different surface modifiers: n-octadecyltrimethoxysilane (OTMS) and N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAPS). The external surface modifiers were introduced through a chemical vapor adsorption (CVA) process. The dynamic light scattering of HNTs dispersed solution indicates that the OTMS-modified HNTs (O-HNTs) are dispersed in THF better than unmodified one. The modified HNTs were mixed with PU resin by solution blending. The PU/O-HNTs nanocomposites show significant improvements in tensile and thermal properties. At 0.5 wt% O-HNTs, the nanocomposite shows large increase in tensile strength and modulus, and 30% increase in elongation at break with respect to the unfilled PU. The simultaneous improvement in modulus, strength, and ductility is attributed to the interaction between the welldispersed O-HNTs and the PU matrix. The application of modified HNTs for flame retardant nanocomposite was done by loading bisphenol-A bis(diphenyl phosphate) (BDP) into the hydrophobically modified lumen of HNTs. The exterior surface was subsequently modified with AEAPS using a CVA process. The AEAPS-modified HNTs containing BDP show improved flame retardant performance without sacrificing the mechanical properties.
All Science Journal Classification (ASJC) codes
- Materials Science(all)