Ionic skin(I-skin)is an emerging skin-inspired sensor that has received increasing interest for the next-generation wearable electronics.However,profound challenges for I-skin remain in achieving multiple signal respo...Ionic skin(I-skin)is an emerging skin-inspired sensor that has received increasing interest for the next-generation wearable electronics.However,profound challenges for I-skin remain in achieving multiple signal responses(e.g.,strain,pressure,and humidity)and self-healability to fully mimic human skin.Herein,a Fe;ion-coordinated poly(acrylic acid)ionogel(PAIFe)with high stretchability,extreme temperature tolerance,and self-healing capability is prepared by a dynamic ionic cross-linking strategy.The ionic coordination in the PAIFe contributes to the formation of a highly dynamic network,achieving its high-efficient and reliable self-healing performance even at a low temperature of-20℃.Using of 1-butyl-3-methylimidazolium tetrafluoroborate([BMIm][BF^(3+)])as the solvent achieves a widetemperature tolerance of the PAIFe under low and high temperatures.More interestingly,a humidity sensing function is realized in the PAIFe by skillfully utilizing the hygroscopic properties of[BMIm][BF_(4)].The resultant PAIFe is proof-ofconcept demonstrated as a deformation-tolerant ionic conductor in a skin-inspired ionic sensor,showing a variety of sensory capabilities towards compression,strain and humidity.展开更多
Eight chiral vinylterphenyl monomers, （＋）-2,5-bis{4＇-[（S）-1＂-methylpropyloxy]phenyl}styrene （Ia）, （＋）-2,5-bis{4＇-[（S）-2＂- methylbutyloxy]phenyl}styrene （Ib）, （＋）-2,5-bis{4＇-[（S）-3＂-methylpenty...Eight chiral vinylterphenyl monomers, （＋）-2,5-bis{4＇-[（S）-1＂-methylpropyloxy]phenyl}styrene （Ia）, （＋）-2,5-bis{4＇-[（S）-2＂- methylbutyloxy]phenyl}styrene （Ib）, （＋）-2,5-bis{4＇-[（S）-3＂-methylpentyloxy]phenyl}styrene （Ic）, （＋）-2,5-bis{4＇-[（S）-4＂- methylhexyloxy]phenyl}styrene （Id）, （-）-2,5-bis{4＇-[（R）-1＂-methylpropyloxy]phenyl}styrene （le）, （＋）-2-/4＇-[（S）-l＂-methyl- propyloxy]phenyl}-5-{4＇-[（R）-1＂-methylpropyloxy]phenyl}styrene （Ⅱa）, （-）-2-{4＇-[（R）-1＂-methylpropyloxy]phenyl}-5-{4＇- [（S）- 1 ＂-methylpropyloxy]phenyl } styrene （lib）, and （＋）-2- { 4＇-[（S）-2＂-methylbutyloxy]phenyl }-5- { 4＇-[（S）- 1＂-methylpropyl- oxy]phenyl}styrene （Ⅲ）, were synthesized and radically polymerized. These molecules were designed to further understand long-range chirality transfer in radical polymerization and to possibly tune the chiroptical properties of the polymers by varying the spatial configuration, position, and various combination of the stereogenic centers at the ends ofp-terphenyl pendants. The resultant polymers adopted helical conformations with a predominant screw sense. When the stereogenic centers ran away from the terphenyl group as in Ⅰb-d, the corresponding polymers changed the direction of optical rotation in an alternative way and showed no obvious stereomutation upon annealing in tetrahydrofuran. The two stereogenic centers of Ⅱa, Ⅱb, and Ⅲ acted concertedly in chiral induction, whereas those of la and Ie played a counteractive role. The five polymers derived from Ⅰa, Ⅰe, Ⅱa, Ⅱb, and Ⅲ underwent stereomutation when annealed in tetrahydrofuran. The polymers PIa-e had good thermal stability and high glass transition temperatures （Tgs）. They generated liquid crystalline phases at above Tgs that could be kept upon cooling, with the exception of Pie. This result was consistent with the extended helical structures.展开更多
基金financially supported by the National Natural Science Foundation of China(21875033 and 52122303)。
文摘Ionic skin(I-skin)is an emerging skin-inspired sensor that has received increasing interest for the next-generation wearable electronics.However,profound challenges for I-skin remain in achieving multiple signal responses(e.g.,strain,pressure,and humidity)and self-healability to fully mimic human skin.Herein,a Fe;ion-coordinated poly(acrylic acid)ionogel(PAIFe)with high stretchability,extreme temperature tolerance,and self-healing capability is prepared by a dynamic ionic cross-linking strategy.The ionic coordination in the PAIFe contributes to the formation of a highly dynamic network,achieving its high-efficient and reliable self-healing performance even at a low temperature of-20℃.Using of 1-butyl-3-methylimidazolium tetrafluoroborate([BMIm][BF^(3+)])as the solvent achieves a widetemperature tolerance of the PAIFe under low and high temperatures.More interestingly,a humidity sensing function is realized in the PAIFe by skillfully utilizing the hygroscopic properties of[BMIm][BF_(4)].The resultant PAIFe is proof-ofconcept demonstrated as a deformation-tolerant ionic conductor in a skin-inspired ionic sensor,showing a variety of sensory capabilities towards compression,strain and humidity.
基金supported by the National Natural Science Foundation of China(21274003)the Research Fund for Doctoral Program of Higher Education of Ministry of Education(20110001110084)
文摘Eight chiral vinylterphenyl monomers, （＋）-2,5-bis{4＇-[（S）-1＂-methylpropyloxy]phenyl}styrene （Ia）, （＋）-2,5-bis{4＇-[（S）-2＂- methylbutyloxy]phenyl}styrene （Ib）, （＋）-2,5-bis{4＇-[（S）-3＂-methylpentyloxy]phenyl}styrene （Ic）, （＋）-2,5-bis{4＇-[（S）-4＂- methylhexyloxy]phenyl}styrene （Id）, （-）-2,5-bis{4＇-[（R）-1＂-methylpropyloxy]phenyl}styrene （le）, （＋）-2-/4＇-[（S）-l＂-methyl- propyloxy]phenyl}-5-{4＇-[（R）-1＂-methylpropyloxy]phenyl}styrene （Ⅱa）, （-）-2-{4＇-[（R）-1＂-methylpropyloxy]phenyl}-5-{4＇- [（S）- 1 ＂-methylpropyloxy]phenyl } styrene （lib）, and （＋）-2- { 4＇-[（S）-2＂-methylbutyloxy]phenyl }-5- { 4＇-[（S）- 1＂-methylpropyl- oxy]phenyl}styrene （Ⅲ）, were synthesized and radically polymerized. These molecules were designed to further understand long-range chirality transfer in radical polymerization and to possibly tune the chiroptical properties of the polymers by varying the spatial configuration, position, and various combination of the stereogenic centers at the ends ofp-terphenyl pendants. The resultant polymers adopted helical conformations with a predominant screw sense. When the stereogenic centers ran away from the terphenyl group as in Ⅰb-d, the corresponding polymers changed the direction of optical rotation in an alternative way and showed no obvious stereomutation upon annealing in tetrahydrofuran. The two stereogenic centers of Ⅱa, Ⅱb, and Ⅲ acted concertedly in chiral induction, whereas those of la and Ie played a counteractive role. The five polymers derived from Ⅰa, Ⅰe, Ⅱa, Ⅱb, and Ⅲ underwent stereomutation when annealed in tetrahydrofuran. The polymers PIa-e had good thermal stability and high glass transition temperatures （Tgs）. They generated liquid crystalline phases at above Tgs that could be kept upon cooling, with the exception of Pie. This result was consistent with the extended helical structures.
