Conductive ionic hydrogels(CIH)have been widely studied for the development of stretchable electronic devices,such as sensors,electrodes,and actuators.Most of these CIH are made into 3D or 2D shape,while 1D CIH(hydrog...Conductive ionic hydrogels(CIH)have been widely studied for the development of stretchable electronic devices,such as sensors,electrodes,and actuators.Most of these CIH are made into 3D or 2D shape,while 1D CIH(hydrogel fibers)is often difficult to make because of the low mechanical robustness of common CIH.Herein,we use gel spinning method to prepare a robust CIH fiber with high strength,large stretchability,and good conductivity.The robust CIH fiber is drawn from the composite gel of sodium polyacrylate(PAAS)and sodium carboxymethyl cellulose(CMC).In the composite CIH fiber,the soft PAAS presents good conductivity and stretchability,while the rigid CMC significantly enhances the strength and toughness of the PAAS/CMC fiber.To protect the conductive PAAS/CMC fiber from damage by water,a thin layer of hydrophobic polymethyl acrylate(PMA)or polybutyl acrylate(PBA)is coated on the PAAS/CMC fiber as a water-resistant and insulating cover.The obtained PAAS/CMC-PMA and PAAS/CMC-PBA CIH fibers present high tensile strength(up to 28 MPa),high tensile toughness(up to 43 MJ/m~3),and good electrical conductivity(up to 0.35 S/m),which are useful for textile-based stretchable electronic devices.展开更多
A series of carboxylated long chain polyethylene glycols(abbreviated as PEGCOOH) has been synthesized and used to support chloroplatinic acid.These supported catalysts were then tested for their efficiency in the hydr...A series of carboxylated long chain polyethylene glycols(abbreviated as PEGCOOH) has been synthesized and used to support chloroplatinic acid.These supported catalysts were then tested for their efficiency in the hydrosilylation of alkenes.The factors affecting their catalytic properties,e.g.relative molecular mass of polyethylene glycol,reaction temperature,platinum content,and type of alkenes,have been studied.It was found that the activity of the platinum catalyst decreased with increasing length of the polyethylene glycol chain,and increased with reaction temperature.Moreover,these catalysts could be reused several times without a noticeable decrease in activity or selectivity.The reaction pathway leading to excellent selectivity for the β-adduct of hydrosilylation of alkenes with triethoxysilane catalyzed by this catalysis system was discussed.展开更多
基金supported by the National Natural Science Foundation of China(No.21778052 and No.21975240)by the Natural Science Foundation of Anhui Province(No.1908085J19)the Talent Research Foundation of Hefei University(No.18-19RC08)。
文摘Conductive ionic hydrogels(CIH)have been widely studied for the development of stretchable electronic devices,such as sensors,electrodes,and actuators.Most of these CIH are made into 3D or 2D shape,while 1D CIH(hydrogel fibers)is often difficult to make because of the low mechanical robustness of common CIH.Herein,we use gel spinning method to prepare a robust CIH fiber with high strength,large stretchability,and good conductivity.The robust CIH fiber is drawn from the composite gel of sodium polyacrylate(PAAS)and sodium carboxymethyl cellulose(CMC).In the composite CIH fiber,the soft PAAS presents good conductivity and stretchability,while the rigid CMC significantly enhances the strength and toughness of the PAAS/CMC fiber.To protect the conductive PAAS/CMC fiber from damage by water,a thin layer of hydrophobic polymethyl acrylate(PMA)or polybutyl acrylate(PBA)is coated on the PAAS/CMC fiber as a water-resistant and insulating cover.The obtained PAAS/CMC-PMA and PAAS/CMC-PBA CIH fibers present high tensile strength(up to 28 MPa),high tensile toughness(up to 43 MJ/m~3),and good electrical conductivity(up to 0.35 S/m),which are useful for textile-based stretchable electronic devices.
基金Supported by the Educational Commission of Zhejiang Province of China (Y201017419)Zhejiang Province Program(2008C14041)
文摘A series of carboxylated long chain polyethylene glycols(abbreviated as PEGCOOH) has been synthesized and used to support chloroplatinic acid.These supported catalysts were then tested for their efficiency in the hydrosilylation of alkenes.The factors affecting their catalytic properties,e.g.relative molecular mass of polyethylene glycol,reaction temperature,platinum content,and type of alkenes,have been studied.It was found that the activity of the platinum catalyst decreased with increasing length of the polyethylene glycol chain,and increased with reaction temperature.Moreover,these catalysts could be reused several times without a noticeable decrease in activity or selectivity.The reaction pathway leading to excellent selectivity for the β-adduct of hydrosilylation of alkenes with triethoxysilane catalyzed by this catalysis system was discussed.