Characterization of the electron beam cure process of an epoxy-initiator system

Abstract

For over forty years high energy electrons have been used to change polymer structure and properties. In this thesis we study the potential use of a high energy electron beam (e-beam) to replace the thermal curing method and offset some of it's disadvantages which are: inability to cure large parts, release of harmful volatiles and high manufacturing and tooling costs. Electron beam curing of the Diglycidyl Ether of Bisphenol A (DGEBA) - I⁺SbF₆⁻ resin initiator system was studied with emphasis on the cure rate, initiator concentration, degree of cure and glass transition temperature. Basic models based on previous thermal curing studies are developed to determine the material properties during cure. It was found that the maximum glass transition temperature obtained was below 100 ⁰C for all initiator concentrations used. The cure rate followed typical arrhenius curves for autocatalytic curing behavior, similar to thermal curing. The cure rate increased with increase in initiator concentration. The temperature profile measured in-situ, and the effects of impurities present were also investigated. Finally the models developed indicate the potential to model and program the cure process to develop materials with desired properties.