The oxides Eu, Ho, Er and Dy were used to prepare the hydroxides of rare earth modified carbon black. Then natural rubber latex (NRL) was added into the reactor. The system reacted at 85 ℃ with stirring for 1 h to ...The oxides Eu, Ho, Er and Dy were used to prepare the hydroxides of rare earth modified carbon black. Then natural rubber latex (NRL) was added into the reactor. The system reacted at 85 ℃ with stirring for 1 h to prepare powdered HAF-Ln(OH)3/NR composites. The effects of the kind and content of Ln on the particle size distribution of P [ NR/HAF-Ln (OH)3 ] and mechanical properties of its vulcanizate were studied respectively. It is found that rare earth can help to get the powder of the composite, the product particle with a diameter less than 0.9mm will be get when the composites containing the compound of Ho, Er and Dy with dosage of 1.0, 1.0, O. 5 percent, respectively. The adding of Ln can improve the tensile strength and tear strength of the vulcanizate effectively, what's more, Er and Dy can decrease the permanent set of vulcanizate significantly. The SEM studies shows that P[ NR/HAF-Dy (OH)3 ] vulcanizate shows superior mechanical properties that depend primarily on the absence of free carbon black, the fine dispersion of carbon black in the rubber matrix and better polymer-filler interaction.展开更多
A series of shape memory polyurethane elastomers(SMPUs) were synthesized by altering the chain extenders.The reaction was proceeding by solution prepolymerization method.Infrared spectra(IR),Differential scanning calo...A series of shape memory polyurethane elastomers(SMPUs) were synthesized by altering the chain extenders.The reaction was proceeding by solution prepolymerization method.Infrared spectra(IR),Differential scanning calorimetry(DSC) and specific viscosity method were carried out to examine the structure,glass transition temperature(Tg) and molecular weight of these SMPUs.The shape memory abilities and tensile properties of the material were investigated simultaneously.The IR results showed that the SMPUs were successfully synthesized and the Tg of the samples were all above 45 ℃ according to the DSC test.All the samples can recover to its original shape completely after bending to 180°.Tensile properties were tested on the samples.The sample MDI/PBAG/BDO with the mole ratio 4/1/3 gets the best tensile strength and highest ultimate elongation.展开更多
The microemulsion polymerization of methyl methacrylate was studied. The effects of feeding modes on the structure and the properties of the obtained polymer microlatex were investigated by measuring the conversion, t...The microemulsion polymerization of methyl methacrylate was studied. The effects of feeding modes on the structure and the properties of the obtained polymer microlatex were investigated by measuring the conversion, the transmittance and the refractive index of the latex, and by measuring the particle size, the molecular weight and the glass transition temperature (T_g) of the polymers. The results show that compared to the batch feeding mode, the semi-continuous feeding mode is more favorable to form a PMMA microlatex with a higher transmittance, a smaller particle size, a higher molecular weight and a higher T_g. And the obtained PMMA microlatex has a 30%—40% (mass fraction) polymer content, a 0. 03 emulsifier/water weight ratio, a 0. 05 emulsifier/monomer weight ratio and a 17 nm average particle diameter, which is very important for the industrialization of the microemulsion polymerization technique.展开更多
It has been proved that introducing isocyanurate into polymer chains could improve the flame retardancy of polymers.We describe in this work the synthesis and the thermal property study of three thermoplastic polyisoc...It has been proved that introducing isocyanurate into polymer chains could improve the flame retardancy of polymers.We describe in this work the synthesis and the thermal property study of three thermoplastic polyisocyanurates,which are polyisocyanuratoamide(PICA-6),polyisocyanurato(ester amide)(PICEA-6)and polyisocyanurato(urea ester)(PICUE-6).These polymers show similar and improved thermal stability with the existence of isocyanurate rings.PICA-6 is more crystalizable than the rest two and the melting temperature is found to be around 240℃ but it still crystalizes slowly.For PICEA-6 and PICUE-6,only glass transition can be observed on the DSC traces.The glass transition temperature follows the order of PICA-6>PICEA-6>PICUE-6(101.9,77.9 and 28.7℃,respectively).展开更多
A novel geminal imidazolium ionic liquid with long hydrocarbon group, 1,4-bis (3-tetradecylimidazolium- 1-yl) butane bromide was synthesized and an efficient synthesized method was introduced detailedly. Its structu...A novel geminal imidazolium ionic liquid with long hydrocarbon group, 1,4-bis (3-tetradecylimidazolium- 1-yl) butane bromide was synthesized and an efficient synthesized method was introduced detailedly. Its structure was determined by FT-IR, ^1H NMR and elemental analysis.展开更多
A side-chain liquid crystalline ionomer(SLCI) was synthesized by grafting copolymerization of 4-(4-ethoxybenzoyloxy)-4'-allyloxybiphenyl and N-allyl-pyridium bromide on polymethylhydrosiloxane. The SLCI was blend...A side-chain liquid crystalline ionomer(SLCI) was synthesized by grafting copolymerization of 4-(4-ethoxybenzoyloxy)-4'-allyloxybiphenyl and N-allyl-pyridium bromide on polymethylhydrosiloxane. The SLCI was blended with polypropylene(PP) and polybutylene terephthalate(PBT) by melt mixing. The thermal behavior, liquid crystalline properties, morphological structure, and mechanical properties of the blends were investigated by differential scanning calorimetry(DSC), polarizing optical microscopy(POM), scanning electron microscopy(SEM), and tensile measurement. When a proper amount of SLCI was added, fine configurations were formed in the PBT/PP/SLCI blend system, and the mechanical properties were improved due to improved adhesion at the interface. When excess SLCI was added, an inhomogeneous structure resulted, which caused the mechanical properties to deteriorate.展开更多
The structures and properties of benzoxazines were investigated by virtue of molecular modeling at a molecular level. By means of Cerius software(version 4.0) supplied by Molecular Simulations Inc., the molecular mech...The structures and properties of benzoxazines were investigated by virtue of molecular modeling at a molecular level. By means of Cerius software(version 4.0) supplied by Molecular Simulations Inc., the molecular mechanics and the molecular dynamics were performed under a PCFF force field. Five kinds of the polymeric chains of benzoxazines were created by using polymer builder and energy minimization. The relaxation process was conducted with both energy minimization and molecular dynamics.展开更多
Although two-dimensional perovskite devices are highly stable,they also lead to a number of challenges.For instance,the introduction of large organic amines makes crystallization process complicated,causing problems s...Although two-dimensional perovskite devices are highly stable,they also lead to a number of challenges.For instance,the introduction of large organic amines makes crystallization process complicated,causing problems such as generally small grain size and blocked charge transfer.In this work,imprint assisted with methylamine acetate were used to improve the morphology of the film,optimize the internal phase distribution,and enhance the charge transfer of the perovskite film.Specifically,imprint promoted the dispersion of spacer cations in the recrystallization process with the assistance of methylamine acetate,thus inhibited the formation of low-n phase induced by the aggregation of spacer cations and facilitated the formation of 3D-like phase.In this case,the corresponding quasi-2D perovskite solar cells delivered improved efficiency and exhibited superior stability.Our work provides an effective strategy to obtain uniform phase distribution for quasi-2D perovskite.展开更多
Luminescent porous materials have shown various applications such as electronic devices, gas adsorption, energy materials and photocatalysis. Consequently, we designed and prepared a new type borondipyrromethene(BODIP...Luminescent porous materials have shown various applications such as electronic devices, gas adsorption, energy materials and photocatalysis. Consequently, we designed and prepared a new type borondipyrromethene(BODIPY) based porous organic polymer(POP) by using Sonogashira coupling reaction. This POP-1 exhibits high thermal stability with moderate surface area. In addition, POP-1 is highly emissive in a solid state. Due to enrichment of different kinds of heteroatoms in the skeleton of the porous polymer, POP-1 selectively captures carbon dioxide(CO_2) with relative high adsorption selectivity of CO_2/N_2.展开更多
A main-chain liquid crystalline ionomer(MLCI) containing sulfonic group was synthesized by an interfacial condensation reaction.The MLCI was blended with polybutylene terephthalate(PBT) and polypropylene(PP).MLC...A main-chain liquid crystalline ionomer(MLCI) containing sulfonic group was synthesized by an interfacial condensation reaction.The MLCI was blended with polybutylene terephthalate(PBT) and polypropylene(PP).MLCI interacted with both the dispersed(PP) phase and the matrix(PBT) phase to modify the interfacial interaction of PBT and PP.Differential scanning calorimetry(DSC),scanning electron microscopy(SEM) and FTIR imaging system analysis demonstrated the significance of interfacial interaction in the polymer blends.MLCI brought about good adhesion at the interfacial,which reduced the disperse phase size and enabled a fine PP phase at matrix.The mechanical properties of the ternary blends were improved when a proper amount of MLCI was added.This was attributed to enhanced adhesion at the interface,which invoked better mechanical properties in the blends.展开更多
A series of thermoreversible konjac glucomannan gels crosslinked by organic borate were prepared. Required amount of hydrophilic SiO2 was added into the konjac glucomannan solutions before the crosslinking reaction, T...A series of thermoreversible konjac glucomannan gels crosslinked by organic borate were prepared. Required amount of hydrophilic SiO2 was added into the konjac glucomannan solutions before the crosslinking reaction, The gel network was formed through the crosslinking reaction between borate ions dissociated from organic borate and the cis-diol hydroxyl groups on the mannose units of polysaccharide chains. The rheological properties of the complex gels were studied by dynamic viscoelastic measurement. The gelation kinetics of the complex gels was studied and the critical getation points of the gels were exactly determined by the Winter-Chambon criterion. The effects of temperature and composite ratio on the shear storage modulus (G'), the loss modulus (G") and the sol-gel transition points were investigated.展开更多
The thermal behavior of thermotropic hydroxyethyl cellulose acetate (HECA)/polyethylene (PE) blends has been studied by DSC. It is found that the blends of HECA and PE are immiscible but the crystallization of PE is a...The thermal behavior of thermotropic hydroxyethyl cellulose acetate (HECA)/polyethylene (PE) blends has been studied by DSC. It is found that the blends of HECA and PE are immiscible but the crystallization of PE is affected by HECA chains in the blends with more than 50% HECA, which results in the subordinate crystallization of PE and the formation of imperfect structures in the PE crystals. The imperfection of PE crystals in the blends can be eliminated after annealing at 393K.展开更多
It is of significance to construct continuous multiphase percolation channels with fast lithium-ion pathway in hybrid solid electrolytes.3D ceramic nanostructure frameworks have attracted great attention in this field...It is of significance to construct continuous multiphase percolation channels with fast lithium-ion pathway in hybrid solid electrolytes.3D ceramic nanostructure frameworks have attracted great attention in this field.Herein,the three-dimensional perovskite Li_(0.33)La_(0.557)TiO_(3)nanotubes framework(3D-LLTO-NT)is fabricated via a facile coaxial electro-spinning process followed by a calcination process at 800°C.The hybrid polymer electrolyte of 3DLLTO-NT framework and poly(ethylene carbonate)(3D-LLTO-NT@PEC)shows improved ionic conductivity of 1.73×10^(-4)S cm^(-1)at ambient temperature,higher lithium-ion transference number(t_(Li)^(+))of 0.78 and electrochemical stability window up to 5.0 V vs Li/Li^(+).The all-solid-state cell of LiFePO_(4)/3D-LLTO-NT@PEC/Li delivers a high specific capacity of 140.2 mAh g^(-1)at 0.1 C at ambient temperature.This outstanding performance is attributed to the 3D ceramic nanotubes frameworks which provide fast lithium ion transfer pathway and stable interfaces.展开更多
Pendent groups' functionalization of polyimide is an optimum approach to improve its processability and achieve functionalized polyimide materials. There are two types of modification routes for pendent groups'...Pendent groups' functionalization of polyimide is an optimum approach to improve its processability and achieve functionalized polyimide materials. There are two types of modification routes for pendent groups' functionalization of polyimide: monomer route and macromolecular route. In this paper, various approaches for pendent groups' functionalization of polyimide are introduced. At the same time, a new method to achieve functional polyimide materials without decreasing its thermal stability and mechanical properties is mentioned.展开更多
For nearly thirty years, there has been made great progress in micro-polymer chemistry experiment teaching which has these characteristics that using less reagents, less pollution and more portable in comparison with ...For nearly thirty years, there has been made great progress in micro-polymer chemistry experiment teaching which has these characteristics that using less reagents, less pollution and more portable in comparison with the conventional experiment. In China, Zhou Ninghuai and others began to go on micro-scale experiment research firstly and Professor Li Qingshan who brought this innovation to polymer organic synthesis experiment has done a lot of works in micro-polymer chemistry experiment teaching. To carry out the study of micro-polymer chemistry experiments not only accords with teaching methods and reform, but also conforms to the trend of the times of green chemistry. So the research and application of micro-polymer chemistry experiment have broad prospects.展开更多
The application of high-performance lithium-sulfur(Li-S)batteries is severely influenced by the“shuttle effect”of polysulfides and the volume change of sulfur cathode.Herein,two different polymeric binders SOT-A and...The application of high-performance lithium-sulfur(Li-S)batteries is severely influenced by the“shuttle effect”of polysulfides and the volume change of sulfur cathode.Herein,two different polymeric binders SOT-A and SOT-C with three-dimensional network structure containing polar groups(sulfhydryl groups,amide groups and amino groups)are synthesized by the nucleophilic ring-opening polymerization(ROP)of thiolactone with amino groups.The network structure formed by hydrogen bonds and functional groups can resist the volume change of the cathode.The sulfhydryl groups and the S-S bond formed by oxidative dehydrogenation of sulfhydryl group participate in the charge and discharge process of the battery as active materials,which improves the discharge specific capacity of the battery.Polar functional groups have strong chemisorption on polysulfides and effectively inhibit the“shuttle effect”.The electrochemical performances of Li-S batteries containing SOT-A and SOT-C binders are significantly enhanced.At 1 C rate,the batteries achieve initial discharge specific capacity of 871 and 837 mAh·g^(-1),respectively,and have 83.9%and 62.5%capacity retention after 500 cycles.展开更多
The spatially controllable shape-shifting behaviors of a planar two-dimensional(2D)film to three-dimensional(3D)shapes upon external stimuli are of paramount significance for the development of smart materials.Herein,...The spatially controllable shape-shifting behaviors of a planar two-dimensional(2D)film to three-dimensional(3D)shapes upon external stimuli are of paramount significance for the development of smart materials.Herein,the present work focuses on fabricating plain film whose shape can be remotely and spatially transformed into various 3D configurations via the formation of a laser-induced temperature gradient;when subjected to laser irradiation,the prestretched hybrid films exhibit out-of-plane bending behavior owing to anisotropic chain relaxation and strain energy release.On this basis,various sophisticated shape transformations can be achieved by site-specific irradiations of laser with a controllable magnitude.Meanwhile,shape morphing involving reversible bending transformations can also be realized by employing the laser on the corresponding opposite side of the hybrid films.Remarkably,under a 160 mW/cm^(2) simulated sunlight illumination,the transformation of flat 2D film into 3D chiral actuators is driven by material anisotropy and geometrical heterogeneity of a bilayer strip design,and it yields right and left-handed helix,the morphologies of the helix shape can be precisely tailored by the strip angles and strain values.展开更多
To improve the dispersibility of carbon nanotubes (CNTs), poly(vinylferrocene-co-styrene) (poly (Vf-co-St)), was grafted onto the surface of CNTs by a ligand-exchange reaction. Poly(Vf-co-St) was obtained by...To improve the dispersibility of carbon nanotubes (CNTs), poly(vinylferrocene-co-styrene) (poly (Vf-co-St)), was grafted onto the surface of CNTs by a ligand-exchange reaction. Poly(Vf-co-St) was obtained by a radical copolymerization reaction using styrene and vinylferrocene as the monomers. The vinylferrocene was synthesized from ferrocene via a Friedel-Crafts acylation. The molecular weight, molecular weight distribution, and amount of Vf in the poly(Vf-co-St) were 1.32 × 104, 1.69 and 17.6% respectively. The degree of grafting of the copolymer onto the CNTs surface was calculated from thermogravimetric analysis and varied from 27.1% to 79.7%. The addition of the poly(Vf-co-St) greatly promoted the dispersibility of the modified CNTs in anhydrous alcohol. The electrical conductivity of compo- sites prepared from the polymer-grafted CNTs and copolymer (acrylonitrile, 1,3-butadiene and styrene, ABS) strongly depended on the degree of grafting. These results show that the amount of polymer grafted onto the surface of CNTs can be controlled and that the electrical properties of composites prepared with these grafted polymers can be tuned.展开更多
Energy-saving glycerol electrolysis with lower potential than water spitting endows a promising way for the concurrent production of value-added formate and high-purity hydrogen. However, there is still lack of effici...Energy-saving glycerol electrolysis with lower potential than water spitting endows a promising way for the concurrent production of value-added formate and high-purity hydrogen. However, there is still lack of efficient electrocatalysts at both anode and cathode for glycerol electrolysis. Herein, we report the activation of Ni site in NiV layered double hydroxide(LDH) by electrochemical and N_(2)/H_(2) plasma regulations for boosting the activity of glycerol oxidation reaction(GOR) and hydrogen evolution reaction(HER), respectively. Specifically, boosted GOR performance with a low overpotential(1.23 V at 10 mA·cm^(-2)) and a high Faradic efficiency(94%) is demonstrated by electrochemically regulated NiV LDH(ENiV LDH) with elevated valence state of Ni site. In situ Raman spectrum reveals the generation of Ni(Ⅲ) species by electrochemical regulation, and the highly active Ni(Ⅲ)can be regenerated with the process of electrochemical oxidation. Additionally, the possible reaction pathway is speculated based on the in situ Fourier transform infrared spectroscopy(FTIR) and high-performance liquid chromatography results. The plasma-regulated NiV LDH(PNiV LDH) with lower valence state of Ni site exhibits outstanding HER activity, displaying a low overpotential of 45 m V to deliver 10 mA·cm^(-2).When employing E-NiV LDH and P-NiV LDH as anode and cathode electrocatalyst, respectively, the assembled electrolyzer merely needs 1.25 V to achieve 10 m A·cm^(-2) for simultaneous production of formate and hydrogen, demonstrating remarkable 320 mV of lower potential than water electrolysis.展开更多
文摘The oxides Eu, Ho, Er and Dy were used to prepare the hydroxides of rare earth modified carbon black. Then natural rubber latex (NRL) was added into the reactor. The system reacted at 85 ℃ with stirring for 1 h to prepare powdered HAF-Ln(OH)3/NR composites. The effects of the kind and content of Ln on the particle size distribution of P [ NR/HAF-Ln (OH)3 ] and mechanical properties of its vulcanizate were studied respectively. It is found that rare earth can help to get the powder of the composite, the product particle with a diameter less than 0.9mm will be get when the composites containing the compound of Ho, Er and Dy with dosage of 1.0, 1.0, O. 5 percent, respectively. The adding of Ln can improve the tensile strength and tear strength of the vulcanizate effectively, what's more, Er and Dy can decrease the permanent set of vulcanizate significantly. The SEM studies shows that P[ NR/HAF-Dy (OH)3 ] vulcanizate shows superior mechanical properties that depend primarily on the absence of free carbon black, the fine dispersion of carbon black in the rubber matrix and better polymer-filler interaction.
基金Funded by Program for New Century Excellent Talents in University
文摘A series of shape memory polyurethane elastomers(SMPUs) were synthesized by altering the chain extenders.The reaction was proceeding by solution prepolymerization method.Infrared spectra(IR),Differential scanning calorimetry(DSC) and specific viscosity method were carried out to examine the structure,glass transition temperature(Tg) and molecular weight of these SMPUs.The shape memory abilities and tensile properties of the material were investigated simultaneously.The IR results showed that the SMPUs were successfully synthesized and the Tg of the samples were all above 45 ℃ according to the DSC test.All the samples can recover to its original shape completely after bending to 180°.Tensile properties were tested on the samples.The sample MDI/PBAG/BDO with the mole ratio 4/1/3 gets the best tensile strength and highest ultimate elongation.
基金Supported by the National Natural Science Foundation of China(No. 29974021) and the Educational Ministry of China.
文摘The microemulsion polymerization of methyl methacrylate was studied. The effects of feeding modes on the structure and the properties of the obtained polymer microlatex were investigated by measuring the conversion, the transmittance and the refractive index of the latex, and by measuring the particle size, the molecular weight and the glass transition temperature (T_g) of the polymers. The results show that compared to the batch feeding mode, the semi-continuous feeding mode is more favorable to form a PMMA microlatex with a higher transmittance, a smaller particle size, a higher molecular weight and a higher T_g. And the obtained PMMA microlatex has a 30%—40% (mass fraction) polymer content, a 0. 03 emulsifier/water weight ratio, a 0. 05 emulsifier/monomer weight ratio and a 17 nm average particle diameter, which is very important for the industrialization of the microemulsion polymerization technique.
基金the financial supports to this work by the National Natural Science Foundation of China(Nos.21404040,21734004,51573061)the Fund of the Key Laboratory of Luminescence from Molecular Aggregates of Guangdong Province,Guangzhou 510640,China(South China University of Technology,No.2019B030301003)the Opening Project Funding of Key Laboratory of Polymer Processing Engineering(South China University of Technology),Ministry of Education,China(No.KFKT1702).
文摘It has been proved that introducing isocyanurate into polymer chains could improve the flame retardancy of polymers.We describe in this work the synthesis and the thermal property study of three thermoplastic polyisocyanurates,which are polyisocyanuratoamide(PICA-6),polyisocyanurato(ester amide)(PICEA-6)and polyisocyanurato(urea ester)(PICUE-6).These polymers show similar and improved thermal stability with the existence of isocyanurate rings.PICA-6 is more crystalizable than the rest two and the melting temperature is found to be around 240℃ but it still crystalizes slowly.For PICEA-6 and PICUE-6,only glass transition can be observed on the DSC traces.The glass transition temperature follows the order of PICA-6>PICEA-6>PICUE-6(101.9,77.9 and 28.7℃,respectively).
文摘A novel geminal imidazolium ionic liquid with long hydrocarbon group, 1,4-bis (3-tetradecylimidazolium- 1-yl) butane bromide was synthesized and an efficient synthesized method was introduced detailedly. Its structure was determined by FT-IR, ^1H NMR and elemental analysis.
基金Supported by the National Natural Science Foundation of China(No50673105)
文摘A side-chain liquid crystalline ionomer(SLCI) was synthesized by grafting copolymerization of 4-(4-ethoxybenzoyloxy)-4'-allyloxybiphenyl and N-allyl-pyridium bromide on polymethylhydrosiloxane. The SLCI was blended with polypropylene(PP) and polybutylene terephthalate(PBT) by melt mixing. The thermal behavior, liquid crystalline properties, morphological structure, and mechanical properties of the blends were investigated by differential scanning calorimetry(DSC), polarizing optical microscopy(POM), scanning electron microscopy(SEM), and tensile measurement. When a proper amount of SLCI was added, fine configurations were formed in the PBT/PP/SLCI blend system, and the mechanical properties were improved due to improved adhesion at the interface. When excess SLCI was added, an inhomogeneous structure resulted, which caused the mechanical properties to deteriorate.
基金Supported by the National Natural Science Foundation of China(No. 5 95 730 0 8) .
文摘The structures and properties of benzoxazines were investigated by virtue of molecular modeling at a molecular level. By means of Cerius software(version 4.0) supplied by Molecular Simulations Inc., the molecular mechanics and the molecular dynamics were performed under a PCFF force field. Five kinds of the polymeric chains of benzoxazines were created by using polymer builder and energy minimization. The relaxation process was conducted with both energy minimization and molecular dynamics.
基金support from the National Natural Science Foundation of China(NSFC)(52163019,22005131,52173169 and U20A20128)support from the Natural Science Foundation of Jiangxi Province(20224ACB214006)。
文摘Although two-dimensional perovskite devices are highly stable,they also lead to a number of challenges.For instance,the introduction of large organic amines makes crystallization process complicated,causing problems such as generally small grain size and blocked charge transfer.In this work,imprint assisted with methylamine acetate were used to improve the morphology of the film,optimize the internal phase distribution,and enhance the charge transfer of the perovskite film.Specifically,imprint promoted the dispersion of spacer cations in the recrystallization process with the assistance of methylamine acetate,thus inhibited the formation of low-n phase induced by the aggregation of spacer cations and facilitated the formation of 3D-like phase.In this case,the corresponding quasi-2D perovskite solar cells delivered improved efficiency and exhibited superior stability.Our work provides an effective strategy to obtain uniform phase distribution for quasi-2D perovskite.
基金Funded by the Natural Science Foundation of China(Nos.21674129 and 21376272)the Post-doctor Foundation of Central South University(No.140050292)
文摘Luminescent porous materials have shown various applications such as electronic devices, gas adsorption, energy materials and photocatalysis. Consequently, we designed and prepared a new type borondipyrromethene(BODIPY) based porous organic polymer(POP) by using Sonogashira coupling reaction. This POP-1 exhibits high thermal stability with moderate surface area. In addition, POP-1 is highly emissive in a solid state. Due to enrichment of different kinds of heteroatoms in the skeleton of the porous polymer, POP-1 selectively captures carbon dioxide(CO_2) with relative high adsorption selectivity of CO_2/N_2.
基金Supported by the High-Tech Research and Development Program of China(No.2006AA02Z291)the National Natural Science Foundation of China(No.50673105)
文摘A main-chain liquid crystalline ionomer(MLCI) containing sulfonic group was synthesized by an interfacial condensation reaction.The MLCI was blended with polybutylene terephthalate(PBT) and polypropylene(PP).MLCI interacted with both the dispersed(PP) phase and the matrix(PBT) phase to modify the interfacial interaction of PBT and PP.Differential scanning calorimetry(DSC),scanning electron microscopy(SEM) and FTIR imaging system analysis demonstrated the significance of interfacial interaction in the polymer blends.MLCI brought about good adhesion at the interfacial,which reduced the disperse phase size and enabled a fine PP phase at matrix.The mechanical properties of the ternary blends were improved when a proper amount of MLCI was added.This was attributed to enhanced adhesion at the interface,which invoked better mechanical properties in the blends.
基金Funded by Chinese Natural Science Foundation Committee(No.50673080)
文摘A series of thermoreversible konjac glucomannan gels crosslinked by organic borate were prepared. Required amount of hydrophilic SiO2 was added into the konjac glucomannan solutions before the crosslinking reaction, The gel network was formed through the crosslinking reaction between borate ions dissociated from organic borate and the cis-diol hydroxyl groups on the mannose units of polysaccharide chains. The rheological properties of the complex gels were studied by dynamic viscoelastic measurement. The gelation kinetics of the complex gels was studied and the critical getation points of the gels were exactly determined by the Winter-Chambon criterion. The effects of temperature and composite ratio on the shear storage modulus (G'), the loss modulus (G") and the sol-gel transition points were investigated.
文摘The thermal behavior of thermotropic hydroxyethyl cellulose acetate (HECA)/polyethylene (PE) blends has been studied by DSC. It is found that the blends of HECA and PE are immiscible but the crystallization of PE is affected by HECA chains in the blends with more than 50% HECA, which results in the subordinate crystallization of PE and the formation of imperfect structures in the PE crystals. The imperfection of PE crystals in the blends can be eliminated after annealing at 393K.
基金financial support from Key Scientific and Technological Project of Wuhan City(Grant no.2018010401011279)Team Innovation Foundation of Hubei province(Grant no.T201935)National Natural Science Foundation of China(Grant nos.51872127,22209059 and 22139001)
文摘It is of significance to construct continuous multiphase percolation channels with fast lithium-ion pathway in hybrid solid electrolytes.3D ceramic nanostructure frameworks have attracted great attention in this field.Herein,the three-dimensional perovskite Li_(0.33)La_(0.557)TiO_(3)nanotubes framework(3D-LLTO-NT)is fabricated via a facile coaxial electro-spinning process followed by a calcination process at 800°C.The hybrid polymer electrolyte of 3DLLTO-NT framework and poly(ethylene carbonate)(3D-LLTO-NT@PEC)shows improved ionic conductivity of 1.73×10^(-4)S cm^(-1)at ambient temperature,higher lithium-ion transference number(t_(Li)^(+))of 0.78 and electrochemical stability window up to 5.0 V vs Li/Li^(+).The all-solid-state cell of LiFePO_(4)/3D-LLTO-NT@PEC/Li delivers a high specific capacity of 140.2 mAh g^(-1)at 0.1 C at ambient temperature.This outstanding performance is attributed to the 3D ceramic nanotubes frameworks which provide fast lithium ion transfer pathway and stable interfaces.
基金Supported by the National Natural Science Foundation of China(No.2 98740 2 1)
文摘Pendent groups' functionalization of polyimide is an optimum approach to improve its processability and achieve functionalized polyimide materials. There are two types of modification routes for pendent groups' functionalization of polyimide: monomer route and macromolecular route. In this paper, various approaches for pendent groups' functionalization of polyimide are introduced. At the same time, a new method to achieve functional polyimide materials without decreasing its thermal stability and mechanical properties is mentioned.
文摘For nearly thirty years, there has been made great progress in micro-polymer chemistry experiment teaching which has these characteristics that using less reagents, less pollution and more portable in comparison with the conventional experiment. In China, Zhou Ninghuai and others began to go on micro-scale experiment research firstly and Professor Li Qingshan who brought this innovation to polymer organic synthesis experiment has done a lot of works in micro-polymer chemistry experiment teaching. To carry out the study of micro-polymer chemistry experiments not only accords with teaching methods and reform, but also conforms to the trend of the times of green chemistry. So the research and application of micro-polymer chemistry experiment have broad prospects.
基金This work was supported by the National Natural Science Foundation of China(Project No.U20A20260)the China Central Government Guide for the Development of Local Science and Technology Special Funds(226Z1202G)the Natural Science Foundation of Hebei Province(Grant Nos.B2020202042,B2020202073 and C20200320).
文摘The application of high-performance lithium-sulfur(Li-S)batteries is severely influenced by the“shuttle effect”of polysulfides and the volume change of sulfur cathode.Herein,two different polymeric binders SOT-A and SOT-C with three-dimensional network structure containing polar groups(sulfhydryl groups,amide groups and amino groups)are synthesized by the nucleophilic ring-opening polymerization(ROP)of thiolactone with amino groups.The network structure formed by hydrogen bonds and functional groups can resist the volume change of the cathode.The sulfhydryl groups and the S-S bond formed by oxidative dehydrogenation of sulfhydryl group participate in the charge and discharge process of the battery as active materials,which improves the discharge specific capacity of the battery.Polar functional groups have strong chemisorption on polysulfides and effectively inhibit the“shuttle effect”.The electrochemical performances of Li-S batteries containing SOT-A and SOT-C binders are significantly enhanced.At 1 C rate,the batteries achieve initial discharge specific capacity of 871 and 837 mAh·g^(-1),respectively,and have 83.9%and 62.5%capacity retention after 500 cycles.
基金supported by the National Natural Science Foundation of China (Grant No.22105152)。
文摘The spatially controllable shape-shifting behaviors of a planar two-dimensional(2D)film to three-dimensional(3D)shapes upon external stimuli are of paramount significance for the development of smart materials.Herein,the present work focuses on fabricating plain film whose shape can be remotely and spatially transformed into various 3D configurations via the formation of a laser-induced temperature gradient;when subjected to laser irradiation,the prestretched hybrid films exhibit out-of-plane bending behavior owing to anisotropic chain relaxation and strain energy release.On this basis,various sophisticated shape transformations can be achieved by site-specific irradiations of laser with a controllable magnitude.Meanwhile,shape morphing involving reversible bending transformations can also be realized by employing the laser on the corresponding opposite side of the hybrid films.Remarkably,under a 160 mW/cm^(2) simulated sunlight illumination,the transformation of flat 2D film into 3D chiral actuators is driven by material anisotropy and geometrical heterogeneity of a bilayer strip design,and it yields right and left-handed helix,the morphologies of the helix shape can be precisely tailored by the strip angles and strain values.
文摘To improve the dispersibility of carbon nanotubes (CNTs), poly(vinylferrocene-co-styrene) (poly (Vf-co-St)), was grafted onto the surface of CNTs by a ligand-exchange reaction. Poly(Vf-co-St) was obtained by a radical copolymerization reaction using styrene and vinylferrocene as the monomers. The vinylferrocene was synthesized from ferrocene via a Friedel-Crafts acylation. The molecular weight, molecular weight distribution, and amount of Vf in the poly(Vf-co-St) were 1.32 × 104, 1.69 and 17.6% respectively. The degree of grafting of the copolymer onto the CNTs surface was calculated from thermogravimetric analysis and varied from 27.1% to 79.7%. The addition of the poly(Vf-co-St) greatly promoted the dispersibility of the modified CNTs in anhydrous alcohol. The electrical conductivity of compo- sites prepared from the polymer-grafted CNTs and copolymer (acrylonitrile, 1,3-butadiene and styrene, ABS) strongly depended on the degree of grafting. These results show that the amount of polymer grafted onto the surface of CNTs can be controlled and that the electrical properties of composites prepared with these grafted polymers can be tuned.
基金the National Science Foundation of China(No.12075002)the Outstanding Youth Fund of Anhui Province(No.2008085J21)+1 种基金Anhui Provincial Supporting Program for Excellent Young Talents in Universities(No.gxyqZD2019005)the Innovation and Entrepreneurship Project of Overseas Returnees in Anhui Province(No.2019LCX018)。
文摘Energy-saving glycerol electrolysis with lower potential than water spitting endows a promising way for the concurrent production of value-added formate and high-purity hydrogen. However, there is still lack of efficient electrocatalysts at both anode and cathode for glycerol electrolysis. Herein, we report the activation of Ni site in NiV layered double hydroxide(LDH) by electrochemical and N_(2)/H_(2) plasma regulations for boosting the activity of glycerol oxidation reaction(GOR) and hydrogen evolution reaction(HER), respectively. Specifically, boosted GOR performance with a low overpotential(1.23 V at 10 mA·cm^(-2)) and a high Faradic efficiency(94%) is demonstrated by electrochemically regulated NiV LDH(ENiV LDH) with elevated valence state of Ni site. In situ Raman spectrum reveals the generation of Ni(Ⅲ) species by electrochemical regulation, and the highly active Ni(Ⅲ)can be regenerated with the process of electrochemical oxidation. Additionally, the possible reaction pathway is speculated based on the in situ Fourier transform infrared spectroscopy(FTIR) and high-performance liquid chromatography results. The plasma-regulated NiV LDH(PNiV LDH) with lower valence state of Ni site exhibits outstanding HER activity, displaying a low overpotential of 45 m V to deliver 10 mA·cm^(-2).When employing E-NiV LDH and P-NiV LDH as anode and cathode electrocatalyst, respectively, the assembled electrolyzer merely needs 1.25 V to achieve 10 m A·cm^(-2) for simultaneous production of formate and hydrogen, demonstrating remarkable 320 mV of lower potential than water electrolysis.