Effect of Silica on the Nonoxidative Thermal Degradation of an Acrylic Binder

Abstract

The nonoxidative thermal decomposition of a polymer binder containing methacrylate and acrylate functionalities is studied by using pyrolysis‐GC/MS, pyrolysis‐GC/FT‐IR, TGA‐MS, and variable‐temperature diffuse reflectance FT‐IR coupled with mass spectrometry (VT‐DRIFT‐MS). At temperatures ranging from 200° to 300°C, polymer pendant groups react with each other, releasing alcohols and water. At higher temperatures (ca. 350°C), the polymer decomposes, yielding ethylene glycol methacrylate and ethylene glycol dimethacrylate as major products. The presence of silica does not significantly alter the polymer degradation product distribution or the temperatures at which pendant group elimination reactions and thermolysis occur. However, silica that was previously heated to 1000°C catalyzes pendant group reactions. KBr exhibits an even greater catalytic effect on these reactions and also affects the temperature at which the major decomposition step occurs.