Optimised Polymerization Conditions for Inkjetting of Caprolactam to Produce Polyamide Parts

Rapid Manufacturing (RM) techniques have been developed to shorten the processing cycle, and lead to efficient production of ready-to-use complex items. This project aims to manufacture three dimensional parts, directly from monomer, using a 3D Printing process based on ink-jet printing technology. A fast polymerization and high monomer conversion are essential. This work describes conditions for the rapid anionic polymerization of caprolactam after inkjetting to produce polyamide (nylon 6) parts. The effect of polymerization temperature and different catalyst/initiator types and concentrations on the rate of reaction were studied. Results show that, although increasing polymerization temperature results in quicker polymerization, the highest polymerization rate is achievable with 0.38g of sodium hydride and 320µl of N-acetylcaprolactam.Mechanical Engineerin