Preparation and Surface Properties of Siloxane-Acrylate Copolymer with High Siloxane Content

Abstract

A copolymer of acrylate and 3-(methacryloxypropyl)-trimethoxysilane (MPS) with high MPS content was prepared by emulsion copolymerisation and characterised by FT-IR, surface tension analysis and the static contact angle method. After Soxhlet extraction, there was scarcely any monomer or homopolymer left in the solvent and the weight losses in all the samples appeared to be negligible, which indicated that almost all the MPS and acrylate monomers had been copolymerised in the reaction. The FT-IR results also supported the same conclusion because there was no C=C peak in the spectrum. The surface tension also was investigated, and the outcome showed that the surface tension decreased with increasing MPS content in the copolymer. The surface properties of the copolymer films were studied by the static contact angle method too. Compared with the acrylate homopolymer, the copolymer containing MPS was more effective in creating a hydrophobic surface and the introduction of MPS was capable of making an obvious increase in water repellency. All the measurements were consistent with the conclusion that a copolymer of siloxane and acrylate with a high siloxane content has been prepared successfully. The siloxane content reached 30%, which was much higher than other reported values.