The preparation and properties study of polydimethylsiloxane-based coatings modified by epoxy resin

In this research, a hydroxyl-terminated polydimethylsiloxane (HTPDMS) was modified by the incorporation of siliconized epoxy resin (SER) containing a segment of siloxane on the side chain of epoxy resin. The chemical structure of the SER was studied by FT-IR, GPC and NMR techniques. Adhesion test showed that the adhesion strength of silicone rubber systems improved markedly after modification. Contact angle (CA) measurements showed the presence of the epoxy block at the surface, which improved adhesion properties of the modified HTPDMS. Morphology studies (SEM) displayed that enhancement in the mechanical properties of the silicone rubber systems due to good compatibility between SER and silicone rubber matrix. Thermogravimetric analysis (TGA) indicated that the residual yield at 800 °C of modified HTPDMS increased compared with that of the neat HTPDMS, but the onset decomposition temperature was reduced with the increase in SER content. These observations highlight the significant role of SER in the modification of HTPDMS.