A series of alkali metal salts doped pluronic block copolymer F127 were used as electron injection/transport layers (ETLs) for polymer light-emitting diodes with poly[2-(4-(3′,7′-dimethyloctyloxy)-phenyl)-p-phenylen...A series of alkali metal salts doped pluronic block copolymer F127 were used as electron injection/transport layers (ETLs) for polymer light-emitting diodes with poly[2-(4-(3′,7′-dimethyloctyloxy)-phenyl)-p-phenylenevinylene] (P-PPV) as the emission layer. It was found that the electron transport capability of F127 can be effectively enhanced by doping with alkali metal salts. By using Li2CO3 (15%) doped F127 as ETL, the resulting device exhibited improved performance with a maximum luminous efficiency (LE) of 13.59 cd/A and a maximum brightness of 5529 cd/m2, while the device with undoped F127 as ETL only showed a maximum LE of 8.78 cd/A and a maximum brightness of 2952 cd/m2. The effects of the doping concentration, cations and anions of the alkali metal salts on the performance of the resulting devices were investigated. It was found that most of the alkali metal salt dopants can dramatically enhance the electron transport capability of F127 ETL and the performance of the resulting devices was greatly improved.展开更多
The hydrogel wound dressing based on polyvinyl alcohol （PVA） was prepared by the freezing-thawing cyclic method. The dehydration kinetics of prepared hydrogels was determined using the experimental method and mathem...The hydrogel wound dressing based on polyvinyl alcohol （PVA） was prepared by the freezing-thawing cyclic method. The dehydration kinetics of prepared hydrogels was determined using the experimental method and mathematical modeling based on diffusion mechanism. The results show that the dehydration rate of PVA hydrogel wound dressing inversely depends on the hydrogel thickness as well as water content of the wound. On the other hand, the initial water content of hydrogel and the atmospheric humidity have little direct effect on the dehydration rate. The good agreement between experimental and mathematical modeling results in early stages of dehydration process shows that the predominate factor determining the dehydration of these wound dressings is diffusion.展开更多
A novel crosslinkable water/alcohol soluble conjugated polymer PFN-C containing oxetane groups and aminoalkyl groups in the side chains has been developed and used as highly efficient electron injection and transporti...A novel crosslinkable water/alcohol soluble conjugated polymer PFN-C containing oxetane groups and aminoalkyl groups in the side chains has been developed and used as highly efficient electron injection and transporting material for polymer light-emitting diodes (PLEDs). The unique solubility in polar solvents and crosslinkable ability of PFN-C render it a good can- didate for solution processed multilayer PLEDs. It was found that PFN-C can greatly enhance the electron injection from high work-function metal cathode, due to its pendant amino groups. As a result, PLEDs with PFN-C/Al cathode exhibited compara- ble device performance to the devices with Ba/Al cathode. The resulting green light-emitting device showed promising perfor- mance with a maximum luminance efficiency of 13.53 cd A-1.展开更多
Polymer functionalization is a powerful tool to prepare polymers with diverse structures without the need of synthesizing monomers or performing polymerization reactions.Polymers that are difficult to be synthesized u...Polymer functionalization is a powerful tool to prepare polymers with diverse structures without the need of synthesizing monomers or performing polymerization reactions.Polymers that are difficult to be synthesized using direct polymerization reactions can be accessed using polymer functionalization.We herein present Mitsunobu derivatization of poly(vinyl alcohol)(PVA)to convert the hydroxyl groups into diverse functional groups.展开更多
A new protein molecularly imprinted polymer (MIP) was prepared with grafting polyvinyl alcohol as assistant recognition polymer chains (ARPCs). The ARPCs and acrylamide monomers were interpenetrated and then polymeriz...A new protein molecularly imprinted polymer (MIP) was prepared with grafting polyvinyl alcohol as assistant recognition polymer chains (ARPCs). The ARPCs and acrylamide monomers were interpenetrated and then polymerized on the surface of macroporous acrylate adsorbent spheres. The template BSA was removed by treatment with 2.00 mol L-1 potassium chloride (KCl) solution and the adsorbed proteins were detected with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). 0.150, 0.500, and 2.00 mol L-1 KCl solutions were used as eluent to wash the adsorbed proteins. The SDS-PAGE results show that proteins washed out with 2.00 mol L-1KCl solution were from nonspecific adsorption of macroporous acrylate adsorbent spheres, and proteins washed out with 0.500 mol L-1KC1 solution were specific proteins imprinted by MIP resins. MIP resins with ARPCs had better recognition to the target proteins than that without ARPCs. The adsorption capacity of MIP resins immobilized ARPCs to the template BSA was about 80-100 μg g-1 when it was used for the adsorption of proteins mixture, and the specific adsorption of the target protein was obviously increased.展开更多
Al<sub>2</sub>O<sub>3</sub>/PVFM/Al<sub>2</sub>O<sub>3</sub> trilayer membranes are prepared by means of simple coating of PVA-Al<sub>2</sub>O<sub>3<...Al<sub>2</sub>O<sub>3</sub>/PVFM/Al<sub>2</sub>O<sub>3</sub> trilayer membranes are prepared by means of simple coating of PVA-Al<sub>2</sub>O<sub>3</sub> solution onto both sides of PVFM thin membranes, which is prepared via phase inversion method. The characteristics of the trilayer membranes and gel polymer electrolytes are investigated using FESEM, tensile testing apparatus, thermal shrinkage test, EIS and charge-discharge test. When inorganic Al<sub>2</sub>O<sub>3</sub> particles are used to coat the PVFM membrane, drawbacks associated with gel-type membranes, namely, poor mechanical strength and thermal stability are greatly improved. Lithium ion cell with the Al<sub>2</sub>O<sub>3</sub>/PVFM/Al<sub>2</sub>O<sub>3</sub> based GPE matched with LiFePO<sub>4</sub> shows excellent electrochemical performance.展开更多
A novel soluble conjugated copolymer (propionic acid)-co-(propargyl alcohol) (PA-co-OHP) has been synthesized for the first time using a new palladium acetylide catalyst Pd(PPh3)(2)(C=CC(CH3)(2)OH)(2)(PPB). Thin film ...A novel soluble conjugated copolymer (propionic acid)-co-(propargyl alcohol) (PA-co-OHP) has been synthesized for the first time using a new palladium acetylide catalyst Pd(PPh3)(2)(C=CC(CH3)(2)OH)(2)(PPB). Thin film resistive humidity sensor based oil the copolymer doped with HClO4 was prepared. The impedance of the sensor changed from 10(3)similar to 10(7) Omega in 95%similar to 30%RH, and the response of that is very quick (<6 sec.). Preliminary results show the copolymer is a promising humidity sensitive material.展开更多
In this paper,morphological structure,thermodynamic compatibility and relationship be-tween porosities and blend ratios of the wet coagulated PU/PVA sheets were studied by meansof observation of scanning electronic mi...In this paper,morphological structure,thermodynamic compatibility and relationship be-tween porosities and blend ratios of the wet coagulated PU/PVA sheets were studied by meansof observation of scanning electronic micrographies,tests of dynamic mechanical properties,moisture regain and vapor permeability.Furthermore,the formation of microvoids at interfacesof separated phases was discussed and a microvoid formation mechanism at phase interfaces ofhydrophobic-hydrophilic blends was suggested and compared with that ofhydrophobic-hydrophobic blends.展开更多
基金supported by the National Natural Science Foundation of China (21125419, 50990065, 51010003, 51073058, and 20904011)National Research Project (2009CB623601 and 2009CB930604)
文摘A series of alkali metal salts doped pluronic block copolymer F127 were used as electron injection/transport layers (ETLs) for polymer light-emitting diodes with poly[2-(4-(3′,7′-dimethyloctyloxy)-phenyl)-p-phenylenevinylene] (P-PPV) as the emission layer. It was found that the electron transport capability of F127 can be effectively enhanced by doping with alkali metal salts. By using Li2CO3 (15%) doped F127 as ETL, the resulting device exhibited improved performance with a maximum luminous efficiency (LE) of 13.59 cd/A and a maximum brightness of 5529 cd/m2, while the device with undoped F127 as ETL only showed a maximum LE of 8.78 cd/A and a maximum brightness of 2952 cd/m2. The effects of the doping concentration, cations and anions of the alkali metal salts on the performance of the resulting devices were investigated. It was found that most of the alkali metal salt dopants can dramatically enhance the electron transport capability of F127 ETL and the performance of the resulting devices was greatly improved.
文摘The hydrogel wound dressing based on polyvinyl alcohol （PVA） was prepared by the freezing-thawing cyclic method. The dehydration kinetics of prepared hydrogels was determined using the experimental method and mathematical modeling based on diffusion mechanism. The results show that the dehydration rate of PVA hydrogel wound dressing inversely depends on the hydrogel thickness as well as water content of the wound. On the other hand, the initial water content of hydrogel and the atmospheric humidity have little direct effect on the dehydration rate. The good agreement between experimental and mathematical modeling results in early stages of dehydration process shows that the predominate factor determining the dehydration of these wound dressings is diffusion.
基金financially supported by the Natural Science Foundation of China (50990065, 51010003, 51073058 & 20904011)the National Basic Research Program of China (973 Program, 2009CB623601)the Fun-damental Research Funds for the Central Universities, South China Uni-versity of Technology
文摘A novel crosslinkable water/alcohol soluble conjugated polymer PFN-C containing oxetane groups and aminoalkyl groups in the side chains has been developed and used as highly efficient electron injection and transporting material for polymer light-emitting diodes (PLEDs). The unique solubility in polar solvents and crosslinkable ability of PFN-C render it a good can- didate for solution processed multilayer PLEDs. It was found that PFN-C can greatly enhance the electron injection from high work-function metal cathode, due to its pendant amino groups. As a result, PLEDs with PFN-C/Al cathode exhibited compara- ble device performance to the devices with Ba/Al cathode. The resulting green light-emitting device showed promising perfor- mance with a maximum luminance efficiency of 13.53 cd A-1.
基金This work was financially supported by the National Natural Science Foundation of China(22075292,22001254)。
文摘Polymer functionalization is a powerful tool to prepare polymers with diverse structures without the need of synthesizing monomers or performing polymerization reactions.Polymers that are difficult to be synthesized using direct polymerization reactions can be accessed using polymer functionalization.We herein present Mitsunobu derivatization of poly(vinyl alcohol)(PVA)to convert the hydroxyl groups into diverse functional groups.
基金supported by the National Natural Science Foundation of China (Grant Nos. 20704031 and 20674040)Science Fund of Tianjin Education Committee (Grant No. 20060515)+1 种基金Natural Science Foundation of Tianjin (Grant No. 09JCYBJC06300)Science Fund of Tianjin University of Science and Technology (Grant No. 20060420)
文摘A new protein molecularly imprinted polymer (MIP) was prepared with grafting polyvinyl alcohol as assistant recognition polymer chains (ARPCs). The ARPCs and acrylamide monomers were interpenetrated and then polymerized on the surface of macroporous acrylate adsorbent spheres. The template BSA was removed by treatment with 2.00 mol L-1 potassium chloride (KCl) solution and the adsorbed proteins were detected with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). 0.150, 0.500, and 2.00 mol L-1 KCl solutions were used as eluent to wash the adsorbed proteins. The SDS-PAGE results show that proteins washed out with 2.00 mol L-1KCl solution were from nonspecific adsorption of macroporous acrylate adsorbent spheres, and proteins washed out with 0.500 mol L-1KC1 solution were specific proteins imprinted by MIP resins. MIP resins with ARPCs had better recognition to the target proteins than that without ARPCs. The adsorption capacity of MIP resins immobilized ARPCs to the template BSA was about 80-100 μg g-1 when it was used for the adsorption of proteins mixture, and the specific adsorption of the target protein was obviously increased.
文摘Al<sub>2</sub>O<sub>3</sub>/PVFM/Al<sub>2</sub>O<sub>3</sub> trilayer membranes are prepared by means of simple coating of PVA-Al<sub>2</sub>O<sub>3</sub> solution onto both sides of PVFM thin membranes, which is prepared via phase inversion method. The characteristics of the trilayer membranes and gel polymer electrolytes are investigated using FESEM, tensile testing apparatus, thermal shrinkage test, EIS and charge-discharge test. When inorganic Al<sub>2</sub>O<sub>3</sub> particles are used to coat the PVFM membrane, drawbacks associated with gel-type membranes, namely, poor mechanical strength and thermal stability are greatly improved. Lithium ion cell with the Al<sub>2</sub>O<sub>3</sub>/PVFM/Al<sub>2</sub>O<sub>3</sub> based GPE matched with LiFePO<sub>4</sub> shows excellent electrochemical performance.
文摘A novel soluble conjugated copolymer (propionic acid)-co-(propargyl alcohol) (PA-co-OHP) has been synthesized for the first time using a new palladium acetylide catalyst Pd(PPh3)(2)(C=CC(CH3)(2)OH)(2)(PPB). Thin film resistive humidity sensor based oil the copolymer doped with HClO4 was prepared. The impedance of the sensor changed from 10(3)similar to 10(7) Omega in 95%similar to 30%RH, and the response of that is very quick (<6 sec.). Preliminary results show the copolymer is a promising humidity sensitive material.
文摘In this paper,morphological structure,thermodynamic compatibility and relationship be-tween porosities and blend ratios of the wet coagulated PU/PVA sheets were studied by meansof observation of scanning electronic micrographies,tests of dynamic mechanical properties,moisture regain and vapor permeability.Furthermore,the formation of microvoids at interfacesof separated phases was discussed and a microvoid formation mechanism at phase interfaces ofhydrophobic-hydrophilic blends was suggested and compared with that ofhydrophobic-hydrophobic blends.
