Effect of Silane-Functionalized Acrylate-Based Copolymer Additive on the Adhesion Properties of Polyolefin Elastomers for Photovoltaic Modules

In this study, an acrylate-based copolymer additive was developed to improve the interfacial adhesion of polyolefin elastomer (POE) encapsulants to glass substrates for photovoltaic (PV) module applications. Two types of copolymers, poly(butyl acrylate-co-octyl acrylate) [Poly(BA-co-OA)] and poly(butyl acrylate-co-octyl acrylate-co-3-(trimethoxysilyl)propyl acrylate) [Poly(BA-co-OA-co-TMSPA)], were synthesized via free-radical polymerization. The incorporation of these copolymers into POE compounds was found to have minimal influence on the thermal and mechanical properties of the neat POE. However, peel adhesion tests revealed that Poly(BA-co-OA-co-TMSPA) significantly enhanced the adhesion strength to glass due to silane-mediated interfacial bonding. Scanning electron microscopy/energy-dispersive X-ray spectroscopy analysis confirmed the homogeneous dispersion of the copolymer additive in the POE matrix. Furthermore, PV modules encapsulated by POE compounds containing the Poly(BA-co-OA-co-TMSPA) exhibited superior durability during a 1000 h damp-heat test, maintaining over 99% of their initial power conversion efficiency. These results demonstrate the potential of silane-functionalized acrylate copolymers as effective adhesion promotors for enhancing the environmental stability of POE-based encapsulants in PV modules.