Dual and Triple Shape Capability of AB Polymer Networks Based on Poly(ε-caprolactone)dimethacrylates

Shape-Memory polymers are an emerging class of functionalized materials, which are able to change their change in a predefined way upon appropriate stimulation. In the past research has mostly focused on the implementation of new ways to trigger the shape-memory effect. Although the stimuli were differing, these systems were dual-shape materials. Recently, multi-phase shape-memory polymers with an additional switching phase were introduced. These materials allow the selection of the switching segment according to the requirements of the specific application. The dual shape-capability and the underlying molecular mechanisms are discussed for such multiphase polymer networks. Furthermore, these materials display triple-shape capability after appropriate programming, which enables them to change from a first shape (A) to a second shape (B) and from there to a third shape (C). Two different polymer network archilectures for triple-shape polymer networks are described and investigated towards their dual and triple shape-properties. The programming of these materials can be fairly complex, therefore we will show finally an one-step programming to reach triple-shape capability.