INJECTION MOLDING OF MICROFEATURES USING THERMOPLASTIC ELASTOMERS

A thermoplastic polyurethane elastomer (TPU) previously demonstrated superior ability to replicate injection molded microscale features abilities in comparison to thermoplastic polymers.  In this work, effects of thermoplastic elastomer properties on the replication of microfeatures were investigated.  Thermoplastic elastomers, including TPUs, copolyesters, polyetheramides and styrenic block copolymers, selected for their type and hardness.  Moldability and ease of ejection were determined during the injection molding of 110-µm wide features.  Replication of the molded parts and tooling was characterized using stereo microscopy, and scanning electron microscopy.  Replication quality was correlated with elastomer properties.