A hydrogel-forming liquid crystalline elastomer exhibiting soft shape memory

Research in the field of liquid crystalline polymers has recently witnessed the introduction of liquid crystalline hydrogels. Here, we report the synthesis and characterization of a new liquid crystalline network featuring elastomeric softness, water-swelling and shape memory characteristics. By comparing with a nonmesogenic network prepared using the same procedure, we reveal structure-property relationships of the liquid crystalline and crystalline polymer networks. Wide angle and small angle X-ray scattering studies were used to examine the liquid crystalline ordering in both dry and hydrated states. Such ordering was found to be related to the observed shape memory and actuation (two-way shape memory) properties and these phenomena are highlighted with demonstrations of shape change in response to heat and water stimuli. This study provides insight into the mechanisms affecting the shape evolution of water activated anisotropic liquid crystalline hydrogels and enables the future design of materials or devices for a variety of applications such as biomaterials interacting with body fluids in a hydrated state.