Anionic polymerisation of caprolactam at the small-scale via DSC investigations

This work was part of a major project aiming to produce polyamide 6 parts using an additive manufacturing process. This is by manufacturing 3D parts layer by layer. The influence of heating strategy (heating rate, cooling rate and maximum temperature) on anionic polymerisation of caprolactam in a small-scale was investigated by means of differential scanning calorimetry (DSC). The relationship between heating rate and the polymerisation–crystallisation processes was determined. Two different catalyst/activator compositions were used to study the influence of a di-functional activator on polymerisation. Results showed that unlike cooling rate, the heating rate and maximum heating temperature had a major effect on the final properties of polymer such as crystallinity, monomer conversion and polymer chains regularity. Using a di-functional activator resulted in slowing down the crystallisation process due to the enhanced rate of branching.