Preparation and characterization of acrylic polymer–nanogold nanocomposites from 3-mercaptopropyltrimethoxysilane encapsulated gold nanoparticles

Abstract

In this study, acrylic polymer–nanogold nanocomposites and their cast films were prepared from an acrylic copolymer and 3-mercaptopropyltrimethoxysilane (MPS) stabilized gold nanoparticles by a sol–gel reaction. The acrylic copolymer was synthesized from methyl methacrylate (MMA) and 3-(trimethoxysilyl)propyl methacrylate (MSMA). The Si–OMe groups of MPS on the surface of gold nanoparticles (MPS–Au) provided the further reaction with the same groups of MSMA, hence the covalent bonds between polymers and MPS–Au nanoparticles were formed. FE-SEM images show MPS–Au nanoparticles are dispersed well in the prepared nanocomposites, and no large aggregation is occurred. TGA results indicate that the decomposed temperatures (Td) of low Au-content (0.1 wt.%) nanocomposites are higher than these of the acrylic copolymer and high Au-content (1.0 wt.%) nanocomposites. The temperature of maximum decomposed rate (Tp) of each prepared nanocomposite is higher than that of the acrylic copolymer. The hardness of the cast film increases with increasing the Au content. The results show the improved thermal stability and application potentials of the prepared acrylic polymer–nanogold nanocomposites.