Function and performance of silicsone copolymers, 3 - Synthesis and properties of a novel siliconized acrylic monomer containing three reactive sites

A novel monomer that contains two secondary crosslinking sites (an active methoxysilane group and an epoxide group) was synthesized from an alkoxy exchange reaction between 2-hydroxyethyl methacrylate (2-HEMA) and 3-glycidoxypropyltrimethoxysilane (Z-6040). This monomer (MSA) was copolymerized with methyl methacrylate using 2,2′-azoisobutyronitrile (AIBN) as an initiator, and its chemical structure was characterized by ¹H NMR. The temperature for 10% weight loss (T₁₀) determined from thermogravimetric analysis (TGA) decreases with increasing MSA content, while the residual weight at 800°C (R₈₀₀) increases with increasing in MSA content. In addition, this monomer can be self-cured via reacting with the moisture in air in the presence of a tin catalyst. The curing reaction is very fast in the first 24 h and almost reaches a plateau value after 7d. Finally, MSA was blended with trimethylolpropane triacrylate (TMPTA) to form a new UV-coating polymer whose critical surface tension is in the range of 24-28 dyn/cm.