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Synthesis and characterization of quaternized poly(phthalazinone ether sulfone ketone)for anion-exchange membrane 被引量:9
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作者 Xi Gao Jian Chun Yan +3 位作者 Hua Min Zhang Shou Hai Zhang Cheng Liu Ping Zhao 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第10期1269-1272,共4页
Chloromethylated poly(phthalazinone ether sulfone ketone) (CMPPESK) was prepared from poly(phthalazinone ether sulfone ketone) (PPESK) using chloromethyl octyl ethers (CMOE) with lower toxicity as chlorometh... Chloromethylated poly(phthalazinone ether sulfone ketone) (CMPPESK) was prepared from poly(phthalazinone ether sulfone ketone) (PPESK) using chloromethyl octyl ethers (CMOE) with lower toxicity as chloromethylated regent. CMPPESK was soluble in N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMAc) and chloroform. Quaternized poly(phthalazinone ether sulfone ketone) (QAPPESK) was prepared from CMPPESK by quaternization. QAPPESK had excellent solvent resistance, which was only partly soluble in sulfuric acid (98%) and swollen in N,N-dimethylformamide (DMF). The vanadium redox flow battery (V-RFB) using QAPPESK anion-exchange membrane had better performance with 88.3% of overall energy efficiency. 展开更多
关键词 CHLOROMETHYLATION QUATERNIZATION poly(phthalazinone ether sulfone ketone) Anion-exchange membrane Vanadium redox flowbattery
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INFLUENCE OF TRACES OF WATER ON THE SYNTHESIS AND ELECTROLUMINESCENCE PROPERTIES OF POLY(2-METHOXY, 5- (2' -ETHYLHEXYL OXY)- 1, 4-PHENYLENE VINYLENE) 被引量:5
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作者 Yue-qi Mo Jian Huang +4 位作者 Jia-xin Jiang Xian-yu Deng Yu-hua Niu Yong Cao Institute of Optoelectronic Materials & Devices Colleg of Material Science and Engineering South China University of Technology,Guangzhou 510640,China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2002年第5期461-465,共5页
It was found that traces of water in the reaction medium would result in a great increase of gel and a decrease of Molecular weight of the poly(2-methoxy,5-(2'-ethylhexyloxy)-1,4-phenylene vinylene) during the pol... It was found that traces of water in the reaction medium would result in a great increase of gel and a decrease of Molecular weight of the poly(2-methoxy,5-(2'-ethylhexyloxy)-1,4-phenylene vinylene) during the polymerization, which ultimately led to inferior film qualities and device properties. The device (ITO/PEDOT/MEH-PPV/Ba/Al) with MEH-PPV prepared under dry conditions has an external quantum efficiency of above 2.0%. 展开更多
关键词 poly(phenylene vinylene) light-emitting diodes
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Synthesis and characterization of novel poly(aryl ether sulfone ketone)s containing phthalazinone and biphenyl moieties 被引量:3
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作者 Li Hong Xiao Cheng Liu Xi Gao Jian 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第2期227-229,共3页
A novel series of poly(aryl ether sulfone ketone)s (PPESKs) containing phthalazinone and biphenyl moieties were prepared by two-step nucleophilic polycondensation reaction. The ^-Mw values of these copolymers were... A novel series of poly(aryl ether sulfone ketone)s (PPESKs) containing phthalazinone and biphenyl moieties were prepared by two-step nucleophilic polycondensation reaction. The ^-Mw values of these copolymers were between 38,330 and 67,900. The glass transition temperatures (Tg) and 5% decomposition temperatures were ranged in 253-269 ℃ and 488-500 ℃, respectively, The structures of these copolymers were confirmed by FT-IR and ^1H NMR. Moreover, all the resultant copolymers were amorphous determined by wide angle X-ray diffraction (WAXD). 展开更多
关键词 poly(aryl ether sulfone ketone) PHTHALAZINONE BIPHENYL Thermal property Solubility
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Allyl-containing Poly(aryl ether sulfone): Synthesis and Crosslinking 被引量:3
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作者 YU Yun-wu XING Yan GUO Mei-mei LIU Bai-jun JIANG Zhen-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第3期520-523,共4页
A novel type of crosslinkable poly(aryl ether sulfone)(PAES) bearing an allyl pendant(PES-OAllyl) was synthesized by a grafting reaction of hydrophenyl-containing PAES(PES-OH) and allyl bromide. PES-OH was pre... A novel type of crosslinkable poly(aryl ether sulfone)(PAES) bearing an allyl pendant(PES-OAllyl) was synthesized by a grafting reaction of hydrophenyl-containing PAES(PES-OH) and allyl bromide. PES-OH was prepared by a demethylation reaction of a methoxyphenylated PAES(PES-OCH3) in the presence of pyridine/hydrochlo- ride. The PES-OCH3 was synthesized by an aromatic nucleophilic substitution of bis(4-chlorophenyl)sulfone and (p-methoxy)phenylhydroquinone. Both DSC and solubility investigation were used to study the crosslinking behavior of PES-OAllyl. After heat treatment, the glass transition temperature(Tg) value of PES-OAllyl sharply increased from 165 ℃ to 227 ℃. Meanwhile, PES-OAllyl changed from a soluble polymer to an insoluble thermoset. In addition, TGA(thermogravimetric analysis) result suggests that the thermal stability of the crosslinked product was improved. All the data prove that the crosslinked PES-OAllyl could be a potential solvent-resistance high-performance material. 展开更多
关键词 CROSSLINKABLE Grafting reaction poly(aryl ether sulfone
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THERMAL DEGRADATION OF POLY(ARYLENE SULFIDE SULFONE)/NMETHYLPYRROLIDONE CRYSTAL SOLVATE 被引量:3
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作者 杨杰 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第1期85-91,共7页
The thermal degradation of poly(arylene sulfide sulfone)/N-methylpyrrolidone (PASS/NMP) crystal solvate was studied by thermogravimetric analysis (TGA) and was compared with pure PASS in order to determine the w... The thermal degradation of poly(arylene sulfide sulfone)/N-methylpyrrolidone (PASS/NMP) crystal solvate was studied by thermogravimetric analysis (TGA) and was compared with pure PASS in order to determine the way in which the formation of the crystal solvate affected the thermal properties of the polymer. The activation energy of the solid state process was determined using Kissinger's method, which does not require knowledge of the reaction mechanism (RM), to be 174.18 kJ/mol which was lower than that for pure PASS (E = 214 kJ/mol). The study of master curves together with interpretation of integral methods, allows confirmation that the thermal degradation mechanism for PASS in the crystal solvate system is a decelerated Rn type, which is a solid-state process based on a phase boundary controlled reaction, in the conversion range considered. Whereas, the pure PASS follows a decelerated Dn thermodegradation mechanism in the same conversion range. 展开更多
关键词 poly(arylene sulfide sulfone Crystal solvate Thermal degradation Thermogravimetric analysis (TGA).
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Proton-exchange Sulfonated Poly(ether ether ketone)/Sulfonated Phenolphthalein Poly(ether sulfone) Blend Membranes in DMFCs 被引量:3
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作者 高启君 王宇新 +2 位作者 许莉 王志涛 卫国强 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第6期934-941,共8页
A sulfonated poly(ether ether ketone) (SPEEK) membrane with fairly high degree of sulfonation (DS) swells excessively and even dissolves at high temperature. To solve these problems, sulfonated phenolphthalein p... A sulfonated poly(ether ether ketone) (SPEEK) membrane with fairly high degree of sulfonation (DS) swells excessively and even dissolves at high temperature. To solve these problems, sulfonated phenolphthalein poly(ether sulfone) (SPES-C, DS= 53.7%) is blended with the SPEEK matrix (DS= 55.1%, 61.7%) to prepare SPEEKJSPES-C blend membrane. The decrease in swelling degree and methanol permeability of the membrane is dose-dependent. Pure SPEEK (DS = 61.7%) membrane dissolves completely in water at 70℃, whereas the swelling degree of the SPEEK (DS = 61.7%)/SPES-C (40%, by mass) membrane is 29.7% at 80℃. From room temperature to 80℃, the methanol permeability of all SPEEK (DS = 55.1%)/SPES-C blend membranes is about one order of magnitude lower than that of Nafion 115. At higher temperature, the addition of SPES-C polymer increases the dimensional stability and greater proton conductivity can be achieved. The SPEEK (DS = 55.1%)/SPES-C (40%, by mass) membrane can withstand temperatures up to 150℃. The proton conductivity of SPEEK (DS = 55.1%)/SPES-C (30%, by mass) membrane approaches 0.16 S·cm^-1, matching that of Nafion 115 at 140℃ and 100% RH, while pure SPEEK (DS = 55.1%) membrane dissolves at 90℃. The SPEEK/SPES-C blend membranes are promising for use in direct methanol fuel cells because of their good dimensional stability, high proton conductivity, and low methanol permeability. 展开更多
关键词 sulfonated poly(ether ether ketone) sulfonated phenolphthalein poly(ether sulfone blend membrane direct methanol fuel cell
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NOVEL HYPERBRANCHED POLY(PHENYLENE OXIDE)S WITH PHENOLIC TERMINAL GROUPS: EFFECTS OF REACTION TIME AND CORE MOLECULES ON THE MOLECULAR WEIGHT AND POLYDISPERSITY 被引量:1
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作者 李效玉 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第4期413-419,共7页
A novel hyperbranched poly(phenylene oxide) (HPPO) with phenolic terminal groups was prepared from 4-bromo-4',4"-dihydroxytriphenylmethane as AB2 monomer in dimethylsulfoxide (DMSO) via a modified Ullmann reac... A novel hyperbranched poly(phenylene oxide) (HPPO) with phenolic terminal groups was prepared from 4-bromo-4',4"-dihydroxytriphenylmethane as AB2 monomer in dimethylsulfoxide (DMSO) via a modified Ullmann reaction. The molecular weight and polydispersity (PD) of the resulting polymers increased with increasing reaction time. In the presence of core molecules (bisphenol A and 1,3,5-trihydroxybenzene), which have the similar molecular backbones to the reactive monomer, the molecular weight could be controlled by varying the core-to-monomer ratio. Incorporation of a very small amount of core molecules could lead to a higher molecular weight as compared with that without the addition of core molecules. However, when the core content reached certain extent, the molecular weight would decrease with the further increase in the core content. A new similar behavior of control over the PD was also obtained. The resulting polymers were characterized by ^1H-NMR, ^13C-NMR, FT-IR, and GPC. 展开更多
关键词 HYPERBRANCHED polyphenylene oxide) Controlled reaction Core molecule.
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Synthesis and Characterization of Ion-exchange Sulfonated Poly (ether sulfone) 被引量:1
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作者 Fan Xiu MENG Chun Qing ZHANG Lian LIU Yuan Yuan ZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第4期447-448,共2页
N,N'-Bis(3-hydroxyphenyl)-1,8,4,5-naphthalenetetracarboxylic bisimide was prepared from the reaction of 1,8,4,5-naphthalenetetrcarboxylic acid dianhydride and 2-aminophenol in N, N-dimethylformamide. Polymerization... N,N'-Bis(3-hydroxyphenyl)-1,8,4,5-naphthalenetetracarboxylic bisimide was prepared from the reaction of 1,8,4,5-naphthalenetetrcarboxylic acid dianhydride and 2-aminophenol in N, N-dimethylformamide. Polymerization of this bisimide with 4,4'-difluorodiphenylsulfone and disodium 3,3'-disulfonate4,4'-difluorodiphenylsulfone gave ion-exchange sulfonated poly(ether sulfone). The structure of the title compound was characterized with H-NMR and its polymer was characterized with FT-IR. 展开更多
关键词 Bisimide ion-exchange polymer sulfonated poly(ether sulfone).
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The Synthesis and Characterization of High Molecular Weight Poly(phenylene sulfide/ether) 被引量:1
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作者 Ai Qun GU Mei Ju XIE Zi Li YU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第10期1373-1376,共4页
Poly(phenylene sulfide/ether) (PPSE) was synthesized from 4,4'-dihydroxydiphenyl sulfide and 4,4'-dichlorodiphenyl sulfide in solution by nucleophilic substitution reaction. The resulting polymer was characteriz... Poly(phenylene sulfide/ether) (PPSE) was synthesized from 4,4'-dihydroxydiphenyl sulfide and 4,4'-dichlorodiphenyl sulfide in solution by nucleophilic substitution reaction. The resulting polymer was characterized by viscosity measurement, elemental analysis, FT-IR, ^1H NMR, X-ray diffraction and thermal analysis. The results showed that the viscosities of the resulting polymer were above 0.68 dL/g, and the linear chain structure of product was confirmed. PPSE had the same reflex indices as poly(p-phenylene sulfide), an orthorhombic crystalline with unit cell a=0.853, b=0.562, c=1.026nm. The melting temperature, glass transition temperature and initial decomposition temperature were found to be 228℃, 85℃ and 325℃, respectively. The product was soluble in common organic solvents such as NMP, N, N'-dimethylformamide, N, N'-dimethylacetamide and 1,2-dichloroethane. 展开更多
关键词 polyphenylene sulfide/ether) (PPSE) SYNTHESIS characterization.
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Sulfonation of Poly(phthalazinone ether sulfone ketone) and Its Application to Isobutene Oligomerization 被引量:1
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作者 ANZengjian ZHOUPeng 《催化学报》 SCIE CAS CSCD 北大核心 2003年第1期1-2,共2页
关键词 聚醚砜酮 磺化 异丁烯 低聚反应 催化剂 聚异丁烯
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CRYSTAL STRUCTURE AND MORPHOLOGY OF NASCENT SAMPLES OF SYMMETRIC AROMATIC POLYESTERS——Ⅰ.POLY(P-PHENYLENE TEREPHTHALATE) 被引量:2
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作者 J.Yang J.Wang +4 位作者 G.Sidoti J.Liu F.Rybnikar M.Kaszonyiova P.H.Geil 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第2期189-204,共16页
The morphology and crytal structure of poly(p-phenylene terephthalate) (PPT), prepared by confined thin filmmelt (CTFMP) and solution (CTFSP) and bulk solution polymerization, were characterized by transmission electr... The morphology and crytal structure of poly(p-phenylene terephthalate) (PPT), prepared by confined thin filmmelt (CTFMP) and solution (CTFSP) and bulk solution polymerization, were characterized by transmission electronmicroscopy, electron dimaction and molecular modeling. The unit cell is monoclinic (P2_1/a space group) with parameters a =7.89, b = 5.49, c = 12.65 A, α=γ= 90°, β=100.33°, density = 1.48 g/cm^3, the a, b and β values differing slightly from thosereported previously in the literature. A degree of variation in relative intensities of hk0 reflections in, apparently, untilted[001] ED patterns was observed from a given sample, suggesting some variation in molecular packing. ED evidence wasfound for a second phase, with [001] appearing the same as for phase Ⅱ of the related poly(p-oxybenzoate) (PpOBA)polymer. CTFMP crystals polymerized above 220℃ (up to 370℃) and CTFSP crystals polymerized at 300℃ consisted oflamellae 100-200 A thick. 展开更多
关键词 poly(p-phenylene terephthalate) Electron diffiaction Crystal structure Confined thin film melt polymerization EPITAXY Morphology
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Synthesis and properties of soluble poly(aryl ether sulfone ether ketone)s copolymers containing pendant methyl groups 被引量:1
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作者 ZHONG Ming YU Wen-wen SONG Cheng LIU Yong-jun SONG Cai-sheng 《Journal of Chemistry and Chemical Engineering》 2009年第4期26-31,38,共7页
A series of Poly(arly ether sulfone ether ketone)s containing pendant methyl groups were synthesized by the reaction of 4,4'-[sulfonylbis (1,4-phenylene)dioxy] dibenzoyl chloride (SODBC) with 4,4'- diphenoxy d... A series of Poly(arly ether sulfone ether ketone)s containing pendant methyl groups were synthesized by the reaction of 4,4'-[sulfonylbis (1,4-phenylene)dioxy] dibenzoyl chloride (SODBC) with 4,4'- diphenoxy diphenylsulfone (DPODPS), 4,4'- di(2-methylphenoxy) diphenylsulfone (o-Me-DPODPS), 4,4'- di(3-methylphenoxy) diphenylsulfone (m-Me-DPODPS), 4,4'- di (2,6-bimethylphenoxy) biphenylsulfone(o-Me2-DPODPS) respectively, in a mixture of 1,2-dichloroethane (DCE) and N-methylpyrrolidone (NMP). These reactions were catalyzed by anhydrous aluminum chloride (AlCl). The characteristic of copolymers were studied by means of advanced analytical techniques such as FT-IR,1H-NMR, DSC, TGA and WAXD. The results show glass transition temperature (Tg) in the range of 193-206℃, thermally stable in excess of 434℃ and excellent solubility in polar solvents. Methyl-substituted Poly(aryl ether sulfone ketone)s had higher glass transition temperatures, lower initial decomposition temperatures than the unsubstituted ones. 展开更多
关键词 poly (aryl ether sulfone ether ketone)s characterization SOLUBLE pendent methyl groups
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The Insulator-to-Conductor Transition in Sulphonated Poly(Phenylene Oxide)Polymer membranes:Percolation Theory Approach
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作者 徐铜文 杨伟华 何炳林 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1998年第4期5-11,共7页
In this paper the percolation theory is employed to study the insulator-to-conductortransition in sulphonated poly(phenylene oxide)(SPPO) polymer membranes.The membranes withdifferent sulphonation degree were prep... In this paper the percolation theory is employed to study the insulator-to-conductortransition in sulphonated poly(phenylene oxide)(SPPO) polymer membranes.The membranes withdifferent sulphonation degree were prepared and infrared characterized.The transition thresholdwas calculated by the experimental data of membrane conductivities and the coordination numberwas thus estimated.The functional group-SO<sub>3</sub>H distribution in the membrane was evaluated inaccordance with the calculations and showed a non-random dispersion on the microscopic scale. 展开更多
关键词 poly(phenylene oxide) polymer ion exchange membrane PERCOLATION THRESHOLD
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EFFECT OF SOLVENT COMPOSITION ON THE SULFONATION DEGREE OF POLY(PHENYLENE OXIDE) (PPO)
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作者 徐铜文 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2002年第1期53-57,共5页
This paper investigates the possibility of attaining sulphonated poly(phenylene oxide) (SPPO) with a relativelyhigher sulfonation degree. To achieve this aim, the approach we adopt is to improve the solubility of the ... This paper investigates the possibility of attaining sulphonated poly(phenylene oxide) (SPPO) with a relativelyhigher sulfonation degree. To achieve this aim, the approach we adopt is to improve the solubility of the final product in themixed solvent so that the sulfonation may take place between the bulk solutions and PPO powders even at higher sulfonationdegree. It is shown that the addition of a proper amount of dimethyl formide (DMF) to the conventional PPO-chloroformsystem can actually enhance the sulfonation effect. The solvent composition is then correlated with the sulfonation degreebased on the solubility parameters. It is interesting to find that solubility parameters between the mixed solvent and theprecipitated products keep an approximately unchanged value at about 4.9, which is just equal to that when pure chloroformis used, though the solubility parameters of both solvents increase with the content of DMF in solution. This may be the mainreason why the addition of DMF can reduce the precipitation and improve the ion exchange capacity (IEC) of SPPOpolymer. 展开更多
关键词 poly(phenylene oxide) SULFONATION Solubility parameter
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SYNTHESIS AND MORPHOLOGICAL STRUCTURE OF POLY (PHENYLENE SULFIDE AMIDE)
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作者 伍齐贤 陈永荣 周祚万 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1995年第2期136-143,共8页
Poly(phenylene sulfide amide) (PPSA) has been synthesized by using sulfur as S source which reacts with dichlorobenzamide (DCBA) and alkali in polar organic solvent at the atmospheric pressure. The polymer structures ... Poly(phenylene sulfide amide) (PPSA) has been synthesized by using sulfur as S source which reacts with dichlorobenzamide (DCBA) and alkali in polar organic solvent at the atmospheric pressure. The polymer structures were determined by elemental analysis, FT-IR and H-1-NMR. It is shown that the yielded polymer has linear structure and its structure unit is -p-C6H4-CONH -p-C6H4-S-. The polymer morphology was studied by X-ray diffraction and polarized microscopy. The results show that PPSA is a crystalline polymer and its spherulites are the aggregation of nontwisting lamella or micro-thread structure. Under shearing force, these crystals are dispersed to form micro-fibrillar structure. The decomposition kinetics of PPSA was also studied at different heating rates. The decomposition energy of PPSA is higher than that of PPS. 展开更多
关键词 polyARYLENE SULFIDE poly (phenylene SULFIDE AMIDE) SYNTHESIS MORPHOLOGICAL STRUCTURE
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GAS SORPTION AND TRANSPORT IN POLY (PHENYLENE OXIDE)(PPO)AND ARYL-BROMINATED PPO MEMBRANES
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作者 贾连达 F. R. SHEU +1 位作者 R.T.CHERN H.B.HOPFENBERG 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1989年第4期306-314,共9页
The apparent solubility (S), concentration-average diffusivity (D), and permeability (P), for C0_2, CH_4 and N_2 through PPO and aryl-brominated PPO at 35℃ for pressure ranging from 1 to 26 atm are reported. It is fo... The apparent solubility (S), concentration-average diffusivity (D), and permeability (P), for C0_2, CH_4 and N_2 through PPO and aryl-brominated PPO at 35℃ for pressure ranging from 1 to 26 atm are reported. It is found that P, D, and S of the membranes to all the three gases vary with the extent of bromination. S increases with the increase of the percent of bromine in each case, but D to CO_2 increases remarkably only at higher degree of brominafion, and therefore, P to CO_2 is increased by more than 100% over a wide range ofpressure in the case. The solubility data are well described by the dual mode sorption model. It is found that the gas molecules sorbed by the Langmuir mode are relatively more immobilized and the contribution of the nonequilibrinm character of the polymer to gas permeation increases obviously for CO_2 and is hardly changed for CH_4 with increasing bromine content. These observations are interpreted in terms of changes in specific free volume (SFV)and the cohesive energy density (CED) of the polymers. 展开更多
关键词 poly (phenylene Oxide) (PPO) BROMINATION Membrane Permeability.
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Poly(meta-phenylene) Derivative with Rigid Twisted Biphenyl Units in Backbone:Synthesis,Structural Characterization,Photophysical Properties and Electroluminescence
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作者 ZHENG Yan YANG Bing ZHANG Hai-quan LU Ping SHEN Fang-zhong LIU Lin-lin XU Hai YANG Guang-di MA Yu-guang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第6期720-725,共6页
A soluble poly(meta-phenylene) derivative with rigid twisted biphenyl unit was synthesized by the Yamamoto coupling reaction. The polymer is soluble in common organic solvents, and the number-average molecular weigh... A soluble poly(meta-phenylene) derivative with rigid twisted biphenyl unit was synthesized by the Yamamoto coupling reaction. The polymer is soluble in common organic solvents, and the number-average molecular weight is about 6500. The UV-Vis and quantum chemical calculation indicate that the different conformation segments named "conformers" exist in the polymer backbones; it was also further confirmed by the single crystal X-ray diffraction study of the dimeric model compound. The π-π^* transition of biphenyl segments of twisted and planar conformations made the polymer exhibit a strong absorption around 256 nm and a weak absorption at about 300 nm. Furthermore, the polymer exhibits a strong UV photoluminescence at 372 nm when the excitation wavelengths are longer than 300 run. The ultraviolet-emitting electroluminescence(EL) device with the single layer structure shows EL λmax of the derivative at 370 nm. 展开更多
关键词 polyphenylene CONFORMATION UV light-emitting
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The Rheological and Extrusion Behaviour of Blends Based on Phenolphthalein Poly(ether-ether-sulfone)and Thermotropic Liquid Crystalline Polymer
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作者 DI Ying-wei D'AMORE Alberto +3 位作者 NICOLAIS Luigi ACIERNO Domenico NOBILE Rossella LI Bin-yao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1998年第3期93-101,共9页
A novel engineering thermoplastic, phenolphthalein poly(ether ether sulfone)(PES C) was blended with a commercial thermotropic liquid crystalline polymer(TLCP), Vectra A950, up to 30 weight percent of TLCP. A rheom... A novel engineering thermoplastic, phenolphthalein poly(ether ether sulfone)(PES C) was blended with a commercial thermotropic liquid crystalline polymer(TLCP), Vectra A950, up to 30 weight percent of TLCP. A rheometrics dynamic spectrometer (RDS Ⅱ) and a CEAST capillary rheometer, a rheoscope 1000 were employed to investigate the melt rheology and extrusion behaviour at both the low and high shearing rates. The morphologies of the blends under different shearing were observed with a scanning electron microscope(SEM) and correlated to the observed rheology. The principal normal stress differences measured with cone and plate geometry give a temperature independent correlation for both blend and PES C when they are plotted against shear stress. But the extrudate swell of the blends showed a strong temperature dependence at each shear stress. The concentration dependence of extrudate swell shows a contrary behaviour to that of the inorganic filled system. A reasonable hypothesis based on the relaxation and disorientation of TLCP during flowing in the capillary and exiting was given to explain it. The melt fracture was checked after extrusion from capillary and was discussed. 展开更多
关键词 Phenolphthalein poly(ether ether sulfone) Thermotropic liquid crystalline polymer BLEND Rheology
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SYNTHESIS AND CHARACTERIZATION OF PHTHALAZINONE POLY(ARYL ETHER SULFONE KETONE)WITH CARBONYL GROUP
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作者 Ying-nan Xuan Yan Gao +1 位作者 Yong Huang Xi-gao Jian Laboratory of Cellulose and Lignocellulosics Chemistry Guangzhou Institute of Chemistry Chinese Academy of Sciences, Guangzhou 510650 China Institute of Chemistry Chinese Academy of Sciences, Beijing 100080 China Department of Polymer Science, College of Chemical Engineering Dalian University of Technology, Dalian 116012, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2002年第3期225-229,共5页
A kind of novel heat-resistant, high performance engineering thermoplastic phthalazinone poly(aryl ether sulfone ketone) (PPESK) containing a carboxyl group in its side chain was prepared by the nucleophilic displacem... A kind of novel heat-resistant, high performance engineering thermoplastic phthalazinone poly(aryl ether sulfone ketone) (PPESK) containing a carboxyl group in its side chain was prepared by the nucleophilic displacement reaction of 4-(4-hydroxylphenyl)- 1 (2H)-phthalazinone with di(4-chlorophenyl) sulfone, 4,4'-difluoro-benzophenone and phenolphthalin in sulfolane in the presence of K2CO3 to produce high molecular weight polymers which can be dissolved in some polar solvents such as chloroform and nitrobenzene at room temperature and can be easily cast into flexible, yellowish and transparent films. PPESK is an amorphous polymer having a decomposition temperature above 400degreesC, which indicates that it has high thermal stability. At the same time, the thermal properties of PPESKs with dicyandiamide (DICY) as curing agent indicated that the heat-resistance properties of the PPESKs are improved after curing. The apparent activation energy (A-E) of the cross-linking reaction and the reaction order (n) of PPESK/DICY were found to be 52.2 kJ/mol and ca. 1.0, respectively. Therefore, the cross-linking reaction is approximately a first order reaction. 展开更多
关键词 poly(aryl ether sulfone ketone) synthesis active pendant group
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Effect of Curing Poly(<i>p</i>-Phenylene Sulfide) on Thermal Properties and Crystalline Morphologies 被引量:1
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作者 Sungho Lee Do-Hwan Kim +3 位作者 Jae-Ha Park Min Park Han-Ik Joh Bon-Cheol Ku 《Advances in Chemical Engineering and Science》 2013年第2期145-149,共5页
Commercial poly(p-phenylene sulfide) (PPS) was thermally cured, which resulted in an increase of molecular weight due to cross-linking. Non-isothermal crystallization studies of samples cured for up to 7 days at 250?C... Commercial poly(p-phenylene sulfide) (PPS) was thermally cured, which resulted in an increase of molecular weight due to cross-linking. Non-isothermal crystallization studies of samples cured for up to 7 days at 250?C showed a monotonous increase of crystallization temperature compared to pure PPS. However, a further increase of curing time decreased the crystallization temperature. The change in the half-crystallization time (t1/2) was similar to the crystallization temperature. Thus, the cross-linking of PPS affected crystallization behaviors significantly. To a certain extent, crosslinks acted as nucleation agents, but excessive cross-linking hindered the crystallization. Morphologies observed by polarized optical microscopy suggested that thermal curing for as little as 1 day contributed to the spherulitic structure having a smaller size, that was not observed with pure PPS. 展开更多
关键词 poly(p-phenylene Sulfide) Thermal CURING Non-Isothermal Crystallization Cross-Linking CRYSTALLINE MORPHOLOGIES
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