A Facile Strategy to Fabricate Multishape Memory Polymers with Controllable Mechanical Properties

A facile blending strategy to fabricate multishape memory polymers (SMPs) with only one sort of phase transition material has been reported. In this work, olefin block copolymer (OBC) and styrene-b-(ethylene-co-butylene)-b-styrene (SEBS), which are both physically crosslinked, are blended with crystalline paraffin together. Due to the different interactions between polymer matrices and paraffin, the paraffin penetrated in OBC and SEBS exhibit separated melting transitions. It is quite interesting that merely paraffin distributed in OBC also shows two distinct melting transitions with enough OBC content in composites. Therefore, excellent quadruple shape memory effect can be achieved with a maximum of three melting transitions. Furthermore, through adjusting the polymer species and content, the mechanical and rheological properties can be conveniently tuned to a great extent. Compared with the reported strategies, this simple and controllable method sheds light on rapid design of multi-SMPs using inexpensive raw materials, which greatly paves the way for multi-SMPs from laboratory to factory.