High-pressure cure kinetics and unexpected cure separation of peroxide-cured silicone rubber under compressed CO2

In this study, high-pressure differential scanning calorimetry (HP-DSC) was used to examine the curing process of a peroxide-cured silicone rubber (SR) system under compressed CO₂ to investigate the influence of pressure and CO₂ on the curing process. We found that the curing reaction occurred in two parts, described as cure separation, because of the dual effect of CO₂ pressure and solvation at 6 MPa CO₂. Consequently, peak fitting was used to calculate the kinetic parameters of the two-part reaction at 6 MPa CO₂. Results indicate that pressure and CO₂ exerted a combined effect on the curing reaction. In particular, pressure and CO₂ solvation effects changed with varying conversion rates and CO₂ pressures. This study provides an effective analysis methodology and an accurate kinetic model for characterizing and predicting high-pressure cure kinetics and unexpected cure separation in a peroxide-cured SR system under compressed CO₂.