Synthesis of PCL/clay masterbatches in supercritical carbon dioxide

Pre-exfoliated nanoclays were prepared through a masterbatch process using supercritical carbon dioxide as solvent and poly(ɛ-caprolactone) as organic matrix. In situ polymerization of ɛ-caprolactone in the presence of large amount of clay was conducted to obtain these easily dispersible nanoclays, collected as a dry and fine powder after reaction. Dispersion of these pre-exfoliated nanoclays in chlorinated polyethylene was also investigated. All the results confirm the specific advantages of supercritical CO2 towards conventional solvents for filler modification.