In this study,a zwitterionic polymer/liquid crystals composite film with programming shape-morphing behavior and humidityresponsive self-healing performance was prepared by blending a zwitterionic polymer and liquid c...In this study,a zwitterionic polymer/liquid crystals composite film with programming shape-morphing behavior and humidityresponsive self-healing performance was prepared by blending a zwitterionic polymer and liquid crystalline azobenzene compound in solution,followed by film-forming in a mold without tedious or multistep synthetic route.The as-obtained zwitterionic polymer/liquid crystal composite film exhibited programming shape-morphing behavior under different stimuli.In this process,the temporary shape of the composite film was memorized after the removal of the stimuli.Such characteristics would fit the requirements of intelligence and energy-saving for stimuliresponsive shape-changing materials.Moreover,the composite film showed humidity-responsive self-healing performances under wet conditions at room temperature.In summary,the simple design and preparation route of the zwitterionic polymer/liquid crystal composite film with programming shape-morphing behavior and mild condition-responsive self-healing performance look promising for the fabrication and practical application of novel photo-driven devices and soft robotics.展开更多
Cellulose macrofibers (MFs) are gaining increasing interest as natural and biodegradable alternatives to fossil-derived polymers for both structural and functional applications. However, simultaneously achieving their...Cellulose macrofibers (MFs) are gaining increasing interest as natural and biodegradable alternatives to fossil-derived polymers for both structural and functional applications. However, simultaneously achieving their exceptional mechanical performance and desired functionality is challenging and requires complex processing. Here, we reported a one-step approach using a tension-assisted twisting (TAT) technique for MF fabrication from bacterial cellulose (BC). The TAT stretches and aligns BC nanofibers pre-arranged in hydrogel tubes to form MFs with compactly assembled structures and enhanced hydrogen bonding among neighboring nanofibers. The as-prepared BC MFs exhibited a very high tensile strength of 1 057 MPa and exceptional lifting capacity (over 340 000 when normalized by their own weight). Moreover, due to the volume expansion of BC nanofibers upon water exposure, BC MFs quickly harvested energy from environmental moisture to untwist the bundled networks, thus generating a torsional spinning with a peak rotation speed of 884 r/(min·m). The demonstrated rapid and intense actuation response makes the MFs ideal candidates for diverse humidity-response-based applications beyond advanced actuators, remote rain indicators, intelligent switches, and smart curtains.展开更多
Developing smart iontronic materials is highly desired for eradicating the widely occurring potential short-circuit hazard and subsequent safety problems caused by high ambient humidity.In this work,a humidity-respons...Developing smart iontronic materials is highly desired for eradicating the widely occurring potential short-circuit hazard and subsequent safety problems caused by high ambient humidity.In this work,a humidity-responsive ionogel(HRIG)based on a poly(benzyl methacrylate)matrix swollen by hydrophobic ionic liquid and hygroscopic lithium salt is reported.The HRIG exhibits an anomalous decrease in ionic conductivity upon hydration by increased humidity,totally differing from traditional ionic conductors,which are usually more conductive due to the plasticizing effect of water molecules.This unique ionogel shows a dramatic decrease in ionic conductivity(as much as 10^(2))when exposed to humidity.The conductive pathway within the HRIG would be shut down spontaneously above a critical relative humidity due to water-induced phase separation.Moreover,this transition can be perfectly reversed when the ambient humidity drops.A humidity-responsive smart supercapacitor that can be switched on and off by capturing humidity changes is designed for demonstration.It is believed that such unusual HRIG material will provide new insights into the development and applications of smart iontronics.展开更多
基金the National Natural Science Foundation of China(Nos.51773120 and 51802201)the Guangdong Basic and Applied Basic Research Foundation(No.2022A1515011985)+1 种基金the Shenzhen Science and Technology Planning Project(Nos.JCYJ20190808115609663 and JCYJ20190808123207674)the Scientific Research Project of Guangdong Provincial Department of Education(No.2020ZDZX2040).
文摘In this study,a zwitterionic polymer/liquid crystals composite film with programming shape-morphing behavior and humidityresponsive self-healing performance was prepared by blending a zwitterionic polymer and liquid crystalline azobenzene compound in solution,followed by film-forming in a mold without tedious or multistep synthetic route.The as-obtained zwitterionic polymer/liquid crystal composite film exhibited programming shape-morphing behavior under different stimuli.In this process,the temporary shape of the composite film was memorized after the removal of the stimuli.Such characteristics would fit the requirements of intelligence and energy-saving for stimuliresponsive shape-changing materials.Moreover,the composite film showed humidity-responsive self-healing performances under wet conditions at room temperature.In summary,the simple design and preparation route of the zwitterionic polymer/liquid crystal composite film with programming shape-morphing behavior and mild condition-responsive self-healing performance look promising for the fabrication and practical application of novel photo-driven devices and soft robotics.
基金support from the Zhejiang Provincial Natural Science Foundation of China(No.LR23C160001)the National Key Research and Development Program of China(No.2021YFD2100504).
文摘Cellulose macrofibers (MFs) are gaining increasing interest as natural and biodegradable alternatives to fossil-derived polymers for both structural and functional applications. However, simultaneously achieving their exceptional mechanical performance and desired functionality is challenging and requires complex processing. Here, we reported a one-step approach using a tension-assisted twisting (TAT) technique for MF fabrication from bacterial cellulose (BC). The TAT stretches and aligns BC nanofibers pre-arranged in hydrogel tubes to form MFs with compactly assembled structures and enhanced hydrogen bonding among neighboring nanofibers. The as-prepared BC MFs exhibited a very high tensile strength of 1 057 MPa and exceptional lifting capacity (over 340 000 when normalized by their own weight). Moreover, due to the volume expansion of BC nanofibers upon water exposure, BC MFs quickly harvested energy from environmental moisture to untwist the bundled networks, thus generating a torsional spinning with a peak rotation speed of 884 r/(min·m). The demonstrated rapid and intense actuation response makes the MFs ideal candidates for diverse humidity-response-based applications beyond advanced actuators, remote rain indicators, intelligent switches, and smart curtains.
基金Program for Guangdong Introducing Innovative and Entrepreneurial Teams,Grant/Award Number:2017ZT07C291National Natural Science Foundation of China,Grant/Award Numbers:22078276,22005260,22073094+4 种基金Shenzhen Science and Technology Program,Grant/Award Number:KQTD20170810141424366Shenzhen Key Laboratory of Advanced Materials Product Engineering,Grant/Award Number:ZDSYS20190911164401990Science and Technology Development Program of Jilin Province,Grant/Award Number:20210402059GHScience and Technology Plan Projects of Yunnan Province,Grant/Award Number:202101BC070001-007Presidential Fund,Grant/Award Number:PF01000949。
文摘Developing smart iontronic materials is highly desired for eradicating the widely occurring potential short-circuit hazard and subsequent safety problems caused by high ambient humidity.In this work,a humidity-responsive ionogel(HRIG)based on a poly(benzyl methacrylate)matrix swollen by hydrophobic ionic liquid and hygroscopic lithium salt is reported.The HRIG exhibits an anomalous decrease in ionic conductivity upon hydration by increased humidity,totally differing from traditional ionic conductors,which are usually more conductive due to the plasticizing effect of water molecules.This unique ionogel shows a dramatic decrease in ionic conductivity(as much as 10^(2))when exposed to humidity.The conductive pathway within the HRIG would be shut down spontaneously above a critical relative humidity due to water-induced phase separation.Moreover,this transition can be perfectly reversed when the ambient humidity drops.A humidity-responsive smart supercapacitor that can be switched on and off by capturing humidity changes is designed for demonstration.It is believed that such unusual HRIG material will provide new insights into the development and applications of smart iontronics.
