A Versatile Polymer Co-Network with Broadened Glass Transition Showing Adjustable Multiple-Shape Memory Effect



In this study, a versatile poly(methyl methacrylate)–poly(ϵ-caprolactone) covalently crosslinked polymer co-network (PMMA–PCL CPN) tethering all polymeric chains between netpoints is designed and prepared to develop a novel type of adjustable multiple-shape memory polymers. The CPN is demonstrated to produce a broadening of glass transition and memorize up to four different shapes based on a single thermal transition for the first time, as the whole energy stored in the broad transition can be distributed into several parts for multi-step shape fixation and recovery in one-shape memory cycle. Furthermore, the versatile multiple-shape memory effects from dual to quadruple can be adjusted simply by shifting the corresponding deformation temperatures on demands, without variation of material chemistry.