Microfabricated therapeutic actuators are fabricated using a shape memory polymer (SMP), a polyurethane-based material that undergoes a phase transformation at a specified temperature (Tg). At a temperature above temperature Tg material is soft and can be easily reshaped into another configuration. As...http://www.google.com.au/patents/US6059815?utm_source=gb-gplus-sharePatent US6059815 - Microfabricated therapeutic actuators and release mechanisms therefor
