The diffusion coefficients(Dapp) and the heterogeneous electron transfer rate constants(ks)for ferrocene in several polymer solvents were determined by using steady-stae voltammetry. Thetemperature dependence of the t...The diffusion coefficients(Dapp) and the heterogeneous electron transfer rate constants(ks)for ferrocene in several polymer solvents were determined by using steady-stae voltammetry. Thetemperature dependence of the two parameters indicates Arrhenius behavior. The polymer solventeffects on diffusion and electron transfer dynamics of ferrocene were discussed展开更多
Styrene was polymerized in supercritical （sc） CO2 with benzoyl peroxide （BPO） as initiator. It was found that the polymerization was accelerated by the external magnetic field.
In this paper,the functional polymeric active materials were prepared by the grafting copolymerization and their structure and properties were studied.The results show that the structure and properties of these ac- ti...In this paper,the functional polymeric active materials were prepared by the grafting copolymerization and their structure and properties were studied.The results show that the structure and properties of these ac- tive materials have the relative large effects on the properties of gadolinium ion selective electrodes.展开更多
Within a Su-Schriffer-Heeger model modified to include electron-electron interaction and an external electric field, we investigate the dynamics of oppositely charged polarons in a polymer chain in the presence of bot...Within a Su-Schriffer-Heeger model modified to include electron-electron interaction and an external electric field, we investigate the dynamics of oppositely charged polarons in a polymer chain in the presence of both electron-phonon and electron-electron interactions under the influence of an external electric field. We adopt a multi-configurational time-dependent Hartree-Fock method for the time-dependent Schrodinger equation and the Newtonian equation of motion for a lattice. Our results show that the on-site Coulomb interaction is of fundamental importance and favors the recombination between the pairs of polarons, and the yield of excitons depends crucially on the strength of the on-site Coulomb interaction U. Furthermore, the influence of the nearest neighbor interaction V is also discussed.展开更多
Three series of polythiophenes containing fluoroalkoxy and fluoroether substituents were prepared by electrochemical polymerization. The effect of substituents with fluoroalkoxy or ether functional groups on the elect...Three series of polythiophenes containing fluoroalkoxy and fluoroether substituents were prepared by electrochemical polymerization. The effect of substituents with fluoroalkoxy or ether functional groups on the electrochemical polymerization of thiophene monomers and properties of the obtained polymers were analyzed. The introduction of a fluoroether functional group at the 3-position of the thiophene ring leads to an increase of the oxidation potential of the monomer and to a decrease of the conductivity of the resulting polymers, even with the use of a CH2 group as spacer. Conversely, the presence of an oxygen atom directly at the 3-position of the thiophene ring, which offsets the negative withdrawing effect of fluoroalkyl groups, facilitates the synthesis of highly conducting polythiophenes.展开更多
Adsorption behaviors of phenol from aqueous solutions have been investigated in batch systems at 303 K and 318 K respectively, using hypercrosslinked polymeric adsorbent （CHA111）, aminated hypercrosslinked polymeric...Adsorption behaviors of phenol from aqueous solutions have been investigated in batch systems at 303 K and 318 K respectively, using hypercrosslinked polymeric adsorbent （CHA111）, aminated hypercrosslinked polymeric adsorbents （NDA101, NDA103, NDA105） and weakly basic polymeric adsorbent （D301） with a view to studying the effect of hydrogen bonding and Van der Waals interactions between adsorbate and the adsorbent. All adsorption isotherms can be well fitted by Langmuir and Freundlich equations. Compared with D301 driven by hydrogen bonding interaction only and CHA111 driven by Van der Waals interaction only, phenol adsorption on aminated adsorbents driven by both hydrogen bonding and Van der Waals interactions were apparently different, i.e., negative effect for NDA105, positive effect for NDA101 and synergistic effect for NDA103. In this synergistic action, some weak interactions would contribute more or less to the adsorption than they work individually.展开更多
Slow-release polymeric fertilizer containing multiple nutrients was synthesized through condensation polymerization from raw materials of homemade low-molecular urea-formaldehyde and the compounds of potassium dihydro...Slow-release polymeric fertilizer containing multiple nutrients was synthesized through condensation polymerization from raw materials of homemade low-molecular urea-formaldehyde and the compounds of potassium dihydrogen phosphate and phosphoric acid. Adjustment of the proportion of raw materials makes the ingredients of the fertilizer are N:P_2O_5:K_2O =1:0.75:0.13, which satisfy the nutritional requirement for maize growth. Field-experiment results prove that the yield of maize increases by 16.56% when using the polymeric fertilizer special for maize alone, by 56.51% when applying the polymeric fertilizer special for maize plus farmyard manure, and by 49.11% when applying the SV fertilizer special for maize plus manure.展开更多
This paper describes the synthesis and free radical ring-opening polymerization of 2-methyl-and 2-methyl-9-n-butyl (-7-methylene-1, 4, 6-trioxaspiro (4, 4) nonane). The structures of the two polymers were verified by ...This paper describes the synthesis and free radical ring-opening polymerization of 2-methyl-and 2-methyl-9-n-butyl (-7-methylene-1, 4, 6-trioxaspiro (4, 4) nonane). The structures of the two polymers were verified by IR, 'H and ^(13)C NMR spectra. The substituent on 9-position of 7-methylene-trioxaspiro (4, 4) nonane affects the structure of polymer and polymerization activity. The polymerization mechanism is discussed.展开更多
Adsorption equilibrium isotherms of phenolic compounds, phenol, p cresol, p chlorophenol and p nitrophenol, from aqueous solutions by Amberlite XAD 4 polymeric adsorbent and its acetylized derivative M...Adsorption equilibrium isotherms of phenolic compounds, phenol, p cresol, p chlorophenol and p nitrophenol, from aqueous solutions by Amberlite XAD 4 polymeric adsorbent and its acetylized derivative MX 4 within temperature range of 283 323K were obtained and fitted to the Freundlich isotherms. The capacities of equilibrium adsorption for all four phenolic compounds from their aqueous solutions increased around 20% on the acetylized resin, which may be contributed to the specific surface area and the partial polarity on the network. Estimations of the isosteric enthalpy, free energy, and entropy for the adsorption process were reported.展开更多
Divinylbenzene-80 （DVB-80） and polar monomer acrylic acid （AA） having hydrogen bonding at a total monomer loading of 5 vol% were precipitated-copolymerized in a variety of organic solvents with 2,2＇-azobis（isobu...Divinylbenzene-80 （DVB-80） and polar monomer acrylic acid （AA） having hydrogen bonding at a total monomer loading of 5 vol% were precipitated-copolymerized in a variety of organic solvents with 2,2＇-azobis（isobutyronitrile） （AIBN） as initiator. The experiments were investigated from a two-dimensional matrix, i.e., the actual crosslinking degree of DVB varying from 0 to 80% and the solvent composition varying from 0 to 100% of toluene mixture with acetonitrile, when the mixture of acetonitrile and toluene was used as the reaction solvent. Under various reaction conditions, six distinct morphologies including soluble polymers, swellable microgels, coagulum, irregular microparticles, and nano-/micrometer microspheres were formed and the structures of these polymer architectures were described. A morphological map was utilized to discuss the effects of both crosslinking degree of DVB and composition of solvent on the transitions between morphology domains. The results demonstrated that the microspheres are formed by an internal contraction due to the marginal solvency of the continuous phase and the crosslinking of the polymer network through the covalent bonding from DVB as well as the interchain hydrogen-bonding between the carboxylic acid units.展开更多
Three unbridged metallocenes, bis(2,4,7-Me3-indenyl)zirconium dichloride(1) , bis(2-Me-4, 7-Et2-indenyl)zirconium dichloride (2) and bis (2, 4, 6-Me3-indenyl) zirconium dichloride (3) were synthesized. The effect of s...Three unbridged metallocenes, bis(2,4,7-Me3-indenyl)zirconium dichloride(1) , bis(2-Me-4, 7-Et2-indenyl)zirconium dichloride (2) and bis (2, 4, 6-Me3-indenyl) zirconium dichloride (3) were synthesized. The effect of solvent polarity on propylene polymerization catalyzed by the metallocenes in the presence of methylaluminoxane(MAO) and triisobutylaluminum(TIBA) was investigated in the toluene/CH2Cl2 mixed solvent. Changing the solvent polarity was found to influence the catalytic activity, polymer molecular weight and stereospecificity of the catalysts. The changes in the position of the substituents on the ligand caused the different responses of the catalyst to the changes in solvent polarity. The isotactic stereosequence of polypropylene was found to increase with the increase in the polarity of the reaction medium.展开更多
文摘The diffusion coefficients(Dapp) and the heterogeneous electron transfer rate constants(ks)for ferrocene in several polymer solvents were determined by using steady-stae voltammetry. Thetemperature dependence of the two parameters indicates Arrhenius behavior. The polymer solventeffects on diffusion and electron transfer dynamics of ferrocene were discussed
基金This work is financially supported by National Key Basic Research Project(G2000048010)the National Natural Science Foundation of China for financial support(29725308).
文摘Styrene was polymerized in supercritical （sc） CO2 with benzoyl peroxide （BPO） as initiator. It was found that the polymerization was accelerated by the external magnetic field.
文摘In this paper,the functional polymeric active materials were prepared by the grafting copolymerization and their structure and properties were studied.The results show that the structure and properties of these ac- tive materials have the relative large effects on the properties of gadolinium ion selective electrodes.
基金Supported by the National Natural Science Foundation of China under Grant No 11474218
文摘Within a Su-Schriffer-Heeger model modified to include electron-electron interaction and an external electric field, we investigate the dynamics of oppositely charged polarons in a polymer chain in the presence of both electron-phonon and electron-electron interactions under the influence of an external electric field. We adopt a multi-configurational time-dependent Hartree-Fock method for the time-dependent Schrodinger equation and the Newtonian equation of motion for a lattice. Our results show that the on-site Coulomb interaction is of fundamental importance and favors the recombination between the pairs of polarons, and the yield of excitons depends crucially on the strength of the on-site Coulomb interaction U. Furthermore, the influence of the nearest neighbor interaction V is also discussed.
基金This work was supported by the National Natural Science Foundation of China.
文摘Three series of polythiophenes containing fluoroalkoxy and fluoroether substituents were prepared by electrochemical polymerization. The effect of substituents with fluoroalkoxy or ether functional groups on the electrochemical polymerization of thiophene monomers and properties of the obtained polymers were analyzed. The introduction of a fluoroether functional group at the 3-position of the thiophene ring leads to an increase of the oxidation potential of the monomer and to a decrease of the conductivity of the resulting polymers, even with the use of a CH2 group as spacer. Conversely, the presence of an oxygen atom directly at the 3-position of the thiophene ring, which offsets the negative withdrawing effect of fluoroalkyl groups, facilitates the synthesis of highly conducting polythiophenes.
基金This study was funded by the National Natural Science Foundation of China(No.20274017)the Natural Science Foundation of Jiangsu Province(No.BK2004415).
文摘Adsorption behaviors of phenol from aqueous solutions have been investigated in batch systems at 303 K and 318 K respectively, using hypercrosslinked polymeric adsorbent （CHA111）, aminated hypercrosslinked polymeric adsorbents （NDA101, NDA103, NDA105） and weakly basic polymeric adsorbent （D301） with a view to studying the effect of hydrogen bonding and Van der Waals interactions between adsorbate and the adsorbent. All adsorption isotherms can be well fitted by Langmuir and Freundlich equations. Compared with D301 driven by hydrogen bonding interaction only and CHA111 driven by Van der Waals interaction only, phenol adsorption on aminated adsorbents driven by both hydrogen bonding and Van der Waals interactions were apparently different, i.e., negative effect for NDA105, positive effect for NDA101 and synergistic effect for NDA103. In this synergistic action, some weak interactions would contribute more or less to the adsorption than they work individually.
基金Supported by the Science and Technology Department of Shanxi Province, China(033004).
文摘Slow-release polymeric fertilizer containing multiple nutrients was synthesized through condensation polymerization from raw materials of homemade low-molecular urea-formaldehyde and the compounds of potassium dihydrogen phosphate and phosphoric acid. Adjustment of the proportion of raw materials makes the ingredients of the fertilizer are N:P_2O_5:K_2O =1:0.75:0.13, which satisfy the nutritional requirement for maize growth. Field-experiment results prove that the yield of maize increases by 16.56% when using the polymeric fertilizer special for maize alone, by 56.51% when applying the polymeric fertilizer special for maize plus farmyard manure, and by 49.11% when applying the SV fertilizer special for maize plus manure.
基金Supported by National Natural Science Foundation of China
文摘This paper describes the synthesis and free radical ring-opening polymerization of 2-methyl-and 2-methyl-9-n-butyl (-7-methylene-1, 4, 6-trioxaspiro (4, 4) nonane). The structures of the two polymers were verified by IR, 'H and ^(13)C NMR spectra. The substituent on 9-position of 7-methylene-trioxaspiro (4, 4) nonane affects the structure of polymer and polymerization activity. The polymerization mechanism is discussed.
文摘Adsorption equilibrium isotherms of phenolic compounds, phenol, p cresol, p chlorophenol and p nitrophenol, from aqueous solutions by Amberlite XAD 4 polymeric adsorbent and its acetylized derivative MX 4 within temperature range of 283 323K were obtained and fitted to the Freundlich isotherms. The capacities of equilibrium adsorption for all four phenolic compounds from their aqueous solutions increased around 20% on the acetylized resin, which may be contributed to the specific surface area and the partial polarity on the network. Estimations of the isosteric enthalpy, free energy, and entropy for the adsorption process were reported.
基金The work was supported by the National Natural Science Foundation of China (Nos. 20274018 and 20504015)the starting-up foundation from Nankai University and Ministry of Education, China.
文摘Divinylbenzene-80 （DVB-80） and polar monomer acrylic acid （AA） having hydrogen bonding at a total monomer loading of 5 vol% were precipitated-copolymerized in a variety of organic solvents with 2,2＇-azobis（isobutyronitrile） （AIBN） as initiator. The experiments were investigated from a two-dimensional matrix, i.e., the actual crosslinking degree of DVB varying from 0 to 80% and the solvent composition varying from 0 to 100% of toluene mixture with acetonitrile, when the mixture of acetonitrile and toluene was used as the reaction solvent. Under various reaction conditions, six distinct morphologies including soluble polymers, swellable microgels, coagulum, irregular microparticles, and nano-/micrometer microspheres were formed and the structures of these polymer architectures were described. A morphological map was utilized to discuss the effects of both crosslinking degree of DVB and composition of solvent on the transitions between morphology domains. The results demonstrated that the microspheres are formed by an internal contraction due to the marginal solvency of the continuous phase and the crosslinking of the polymer network through the covalent bonding from DVB as well as the interchain hydrogen-bonding between the carboxylic acid units.
基金National Natural Science Foundation of China and SINOPEC(No.29734144).
文摘Three unbridged metallocenes, bis(2,4,7-Me3-indenyl)zirconium dichloride(1) , bis(2-Me-4, 7-Et2-indenyl)zirconium dichloride (2) and bis (2, 4, 6-Me3-indenyl) zirconium dichloride (3) were synthesized. The effect of solvent polarity on propylene polymerization catalyzed by the metallocenes in the presence of methylaluminoxane(MAO) and triisobutylaluminum(TIBA) was investigated in the toluene/CH2Cl2 mixed solvent. Changing the solvent polarity was found to influence the catalytic activity, polymer molecular weight and stereospecificity of the catalysts. The changes in the position of the substituents on the ligand caused the different responses of the catalyst to the changes in solvent polarity. The isotactic stereosequence of polypropylene was found to increase with the increase in the polarity of the reaction medium.
