writer：Yaxin Qiu, Qianru Wanyan, Wenting Zhang, Suna Yin, Defeng Wu
keywords：crosslinking networks; spatial distribution; shape-memory behavior; multi-material actuator
source：期刊
specific source：Journal of Materials Chemistry A, 2020, 8, 17193-17201
Issue time：2020年

Increasing the spatial localization of the material response is crucial to increase the behavioral complexity of shape-memory polymer (SMP) actuators, which is strongly dependent on the spatial distribution of networks in SMP. An interesting approach is proposed in this work. We used diol crosslinkers with different fatty chain lengths to construct networks in biomass-derived poly(L-malic acid) (PMA), and thus obtained SMPs with different network geometries. The crosslinking followed a two-step route: esterification for pre-crosslinks, and further curing to obtain target sample. Combining different pre-cross-linked pieces together, followed by curing then, is an effective way programming spatial distribution of crosslinks, and by this way to give the behavioral complexity to a SMP bulk. Besides, using as-obtained SMP bulk as compound ‘joint’, the multimaterial systems with step-by-step responding capacities could be fabricated to better complete a series of sophisticated and asynchronous movements. This work enriches approaches of combining polymer architecture and macroscale processing to improve programmable recovery and actuation in SMPs.

https://pubs.rsc.org/en/content/articlelanding/2020/ta/d0ta05660j#!divAbstract