Study of Applying Naturally Occurring Mineral Materials for Silicone Pressure-Sensitive Adhesives

Materials (Basel). 2023 Mar 3;16(5):2092. doi: 10.3390/ma16052092.

Abstract

Silicones are commonly used as adhesives when high-quality materials are required due to harsh environmental conditions such as high temperature, humidity, etc. To ensure high resistance to environmental conditions, including high temperatures, modifications of silicone adhesives are made using fillers. The characteristics of a modified silicone-based pressure-sensitive adhesive with filler are the focus of this work. Functionalized palygorskite was prepared in this investigation by grafting 3-mercaptopropyltrimethoxysilane (MPTMS) onto palygorskite (palygorskite-MPTMS). The palygorskite was functionalized using MPTMS under dried conditions. FTIR/ATR spectroscopy, thermogravimetric analysis, and elemental analysis were all used to characterize the obtained palygorskite-MPTMS. MPTMS loading onto palygorskite was also proposed. The results demonstrated that palygorskite's initial calcination favors the grafting of functional groups on its surface. New self-adhesive tapes based on palygorskite-modified silicone resins have been obtained. This functionalized filler allows for the improvement of the compatibility of palygorskite with specific resins for application in heat-resistant silicone pressure-sensitive adhesives. The new self-adhesive materials showed increased thermal resistance while maintaining good self-adhesive properties.

Keywords: filler modification; functionalized palygorskite; grafting of 3-mercaptopropyltrimethoxysilane; new self-adhesive tapes.