Surface modification of talc powder by silane functionalized polycarboxylates and its effect on the performance of polyvinyl chloride composite

In this work, modified polycarboxylates were prepared by copolymerizing γ-Methacryloxy propyl trimethoxyl silane (KH-570) with acrylic acid and allyl polyoxyethylene ether. Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) indicate that silane copolymerized polycarboxylates have been successfully synthesized. The talc powder (TP) modified with synthesized polycarboxylate and modified polycarboxylates was blended with polyvinyl chloride (PVC) to prepare composite films. FTIR and x-ray photoelectron spectroscopy (XPS) were used to determine changes in the surface properties of unmodified and modified TP. The effects of TP and polycarboxylate-modified TP on the tensile properties, light transmission and moisture transmission of the PVC composite films were investigated. Compared with untreated TP filled PVC film, the PVC composite films filled with organosilicon polycarboxylate-modified TP exhibit enhanced tensile strength, light transmittance, barrier, and other properties. Especially, the tensile strength of PVC composite film filled with 7 wt% Si_0.5-PCE modified TP is increased by 19.5% and the elongation at break is increased by 21.6%. In addition, the moisture permeability of the composite film is reduced by a maximum of 80.6% compared with the pure PVC film.