The simple LBL technique was introduced to fabricate green nacre-like chatosan/montmorillonite （CHI/MMT） films. The results of SEM and XRD analysis demonstrate that the produced CHI/MMT composites films stacked dens...The simple LBL technique was introduced to fabricate green nacre-like chatosan/montmorillonite （CHI/MMT） films. The results of SEM and XRD analysis demonstrate that the produced CHI/MMT composites films stacked densely together to bring out well-defined nacre-like brick-mortar structure. The nanoindentation technique is used to characterize the mechanical properties of the layered nanocomposite films, which show enhanced mechanical modulus （up to -6.64 GPa） compared with the pure chitosan.展开更多
The fluorescent probe techniques have been widely applied.When the fluorescence probes are selectively located in nanostructures,the fluorescence properties are highly influenced by the environment.Here,we systematica...The fluorescent probe techniques have been widely applied.When the fluorescence probes are selectively located in nanostructures,the fluorescence properties are highly influenced by the environment.Here,we systematically studied the location-influenced fluorescence of AIEgens in the microphase-separated structures.The AIEgen tetraphenylethene (TPE) was doped into polystyrene-bpolyisoprene (PS-b-Pl).TPE was selectively located in the PS nanodomains.The TPE fluorenscence was affected by the structural relaxation of PS when investigated in a wide range of temperatures,including the glass transiton and secondary transiton.When TPE groups were selectively located in the PI nanodomains,the fluorenscence was affected by the glass transitons of PI and PS blocks.Amphiphilic TPE derivative was located at the interface of the assembly.The fluorescence emission was influenced by the main transition and secondary transiton of PS blocks,as well as the main transition of PI blocks.These results would give new understanding of the interrelation between fluorescence probes and the nanostructures.展开更多
The ionic conductivity and the mechanical strength are two key factors for the performance of poly（ethylene oxide）（PEO） based polyelectrolytes. However, crystallized PEO suppresses ion conductivity at low temperat...The ionic conductivity and the mechanical strength are two key factors for the performance of poly（ethylene oxide）（PEO） based polyelectrolytes. However, crystallized PEO suppresses ion conductivity at low temperature and melted PEO has low mechanical strength at high temperature. Here, random binary brush copolymer composed of PEO-and polystyrene（PS）-based side chains is synthesized. PEO crystallinity is suppressed by the introduction of PS brushes. Doping with lithium trifluoromethanesulfonate（Li Tf） induces microphase separation. Due to a random arrangement of the brushes, the microphase segregation is incomplete even at high salt loading, which provides both high ionic conductivity and high mechanical strength at room temperature. These results provide opportunities for the design of polymeric electrolytes to be used at room temperature.展开更多
基金financially supported by the National Basic Research Program of China(No.2010CB934700)the Doctoral Fund of Innovation of Beijing University of Technology
文摘The simple LBL technique was introduced to fabricate green nacre-like chatosan/montmorillonite （CHI/MMT） films. The results of SEM and XRD analysis demonstrate that the produced CHI/MMT composites films stacked densely together to bring out well-defined nacre-like brick-mortar structure. The nanoindentation technique is used to characterize the mechanical properties of the layered nanocomposite films, which show enhanced mechanical modulus （up to -6.64 GPa） compared with the pure chitosan.
基金financially supported by the National Natural Science Foundation of China (Nos. 21875009 and 51703006)the Fundamental Research Funds for the Central Universities
文摘The fluorescent probe techniques have been widely applied.When the fluorescence probes are selectively located in nanostructures,the fluorescence properties are highly influenced by the environment.Here,we systematically studied the location-influenced fluorescence of AIEgens in the microphase-separated structures.The AIEgen tetraphenylethene (TPE) was doped into polystyrene-bpolyisoprene (PS-b-Pl).TPE was selectively located in the PS nanodomains.The TPE fluorenscence was affected by the structural relaxation of PS when investigated in a wide range of temperatures,including the glass transiton and secondary transiton.When TPE groups were selectively located in the PI nanodomains,the fluorenscence was affected by the glass transitons of PI and PS blocks.Amphiphilic TPE derivative was located at the interface of the assembly.The fluorescence emission was influenced by the main transition and secondary transiton of PS blocks,as well as the main transition of PI blocks.These results would give new understanding of the interrelation between fluorescence probes and the nanostructures.
基金financial support from the National Key Research and Development Program of China(2017YFA0206904,2017YFA0206900)start-up fund of Changchun Institute of Applied Chemistry,Chinese Academy of Sciences
文摘The ionic conductivity and the mechanical strength are two key factors for the performance of poly（ethylene oxide）（PEO） based polyelectrolytes. However, crystallized PEO suppresses ion conductivity at low temperature and melted PEO has low mechanical strength at high temperature. Here, random binary brush copolymer composed of PEO-and polystyrene（PS）-based side chains is synthesized. PEO crystallinity is suppressed by the introduction of PS brushes. Doping with lithium trifluoromethanesulfonate（Li Tf） induces microphase separation. Due to a random arrangement of the brushes, the microphase segregation is incomplete even at high salt loading, which provides both high ionic conductivity and high mechanical strength at room temperature. These results provide opportunities for the design of polymeric electrolytes to be used at room temperature.
