最新刊期
卷 ， 期 3 ， 1998
- 摘要：The effects of physical aging on the structure and solvent induced crystallization(SINC) rate of PET fibers were studied by density measurement,d.s.c.and mechanical property test.Furthermore the effect of orientation on the crystallization rate of annealed PET fibers was studied.At a certain physical aging temperature below Tg,the SINC rate of PET showed an initial decrease but a later increase with the increasing of physical aging time.The effect of physical aging on crystallization has an obvious relation with different orientation states in PET fibers.Samples with higher orientation would show an increase in crystallization are after annealing time.These phenomena were explained by cohesional entanglement viewpoint.
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发布时间：2021-03-19 - 摘要：Single component and multi component of iron system colloidal catalyst Fe(naph)2 Al(i- Bu)3 CH2 CHCH2Cl were mixed by different ratios in hydrogenated gasoline medium at 25℃.This paper studied the relationship between the nonaqueous systematic electroconductivity and the concentration of catalyst components.In combination with Tyndall effect,polymerization experimental results,Al(i-Bu)3 existed in associated state and dissociated into ionpair.The reaction between Al(i-Bu)3 and Fe(naph)2 was the main reaction which formed colloidal core.Al(i-Bi)3 reacted on CH2=CHCH2Cl and Al(i-BU)2Cl was yielded which joined the formation of active center on the surface of colloidal core.The excessive Al(i-Bu)3 was dissociated into ionpair which formed double electrode layer,and the double electrode layer kept the colloidal particles relatively stable.The optimal components ratio of the catalyst formed stable colloidal particles which were tiny,uniform and with high catalytic activity.When butadiene was added into the catalytic system the decline of the electroconductivity showed that the active center was the positive ionicity.
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发布时间：2021-03-19 - 摘要：The solution cyclocopolymerization of 1,3 divinyl 1,1,3,3-tetramethyldisiloxane(DVDS) with styrene(St) at 130℃ was investigated.The overall conversions for all copolymerization runs were controlled less than 10%.The copolymer compositions and percentages of DVDS forming the ring structures in the copolymers were determined by1H and 29Si NMR,respectively.Using the nonlinear parameter estimation,the cyclization coefficients and reactivity ratios were calculated as r1=0. 102,r2=34.8,rc=0.0210,Kc=3.81mol/L, and K'c=0.389mol/L.The 95% reliability intervals for the estimated kinetic constants were given also.The experimental results indicate that DVDS was less active than St,and the DVDS uncyclized radicals were easy to form the cyclic structures via the intramolecular cyclization. Due to the steric hindrance,the activities of DVDS cyclized radicals were lower than its uncyclized ones.
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发布时间：2021-03-19 - 摘要：Presents the FTIR spectra and spectral manipulatioins of liquid crystalline polymer (LCP) blends with polystyrene (PS) and modified polystyrene,lightly sulfonated polystyrene (HSPS).Earlier DSC and SEM studies have demonstrated that HSPS is completely miscible with LCP,although their molecular structure differs greatly from each other,whereas PS is immiscible with LCP.FTIR study now elucidates the origin of miscibility enhancing is the presence of specific interactions involving the carbonyl groups and C —O groups in the LCP and sulfonate groups in the HSPS molecular chains,resulting in very intimate mixin of the HSPS with the LCP's segment.
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发布时间：2021-03-19 - 摘要：O butyryl chitosan which was prepared from chitosan demonstrated lyotropic liquid crystalline behavior in various solvents,for example,water,methanol,formic acid,acetic acid,dichloroacetic acid(DCA),trifluoroacetic acid,dimethyl sulfoxide,acrylic acid,m cresol,foramide,N,N-dimethyl acetamide.The typical fingerprint texture of cholesteric phase can be observed.Critical concentrations of butyryl chitosan in four acidic solvents were determined using polarized microscopy.All critical concentration values(calculated by v/v%) were 16～17%,independent of the acdity of solvent.This result was similar to that of chitosan.Since the protonation of amine with acid is easy even though the acid is weak,the rigidity of chain(Therefore the critical concentration)did not depend on acidity of solvents.Critical temperature of butyryl chitosan/DCA system was measured by DSC.The phase diagram was drawn.Critical temperature reached maximum values of 39℃ when concentration was 60% (w/w%).Because butyryl chitosan would degrade in DCA,the enthapy of transition calculated from DSC traces started to decrease at 48h after the solution was prepared.So the best staying time of solution before DSC determination is 48h.The dependence of butyrylation degree on critical concentration was studied.Two butyryl chitosan samples with relatively differnt degree of butyrylation which was measured by IR had the same critical concentration values in DCA.
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发布时间：2021-03-19 - 摘要：The poly(cyanoarylether) was a new thermoplast being used as the basis of resin and engineering material in high property composite material.It exhibited high temperature stability,and resistance to radiation and to solvent attack.Crystalline ploy(cyanoarylether) could be prepared by the polycondensation of 2,6 difluorobenzonitrile with resorcinol at 200℃ in N methylpyrrolidone (with less water) in the presence of sodium carbonate.The reaction was affected by some conditions like temperature,polymer concentration and reaction time. A reaction temperature of at least 200℃ was necessary to attain high molecular weight polymer.Less water that was added in reaction mixture could improve reaction rate,and enhance molecular weight of the polymer.Spectral data indicated that the polymer had the structure of a poly(meta-phenylene ether) with pendent nitrile.The glass transition temperature and the melting temperature of the polymer were examined to be 148℃ and 335℃ bu turn.A cool crystalline exothermal peak appeared at 214.4℃.The decomposition temperature(loss weight 5%)and all weight loss by 900℃ of polymer were speculated from TG curve.The results showed the polymer had a fire-resistance and aging resistance properties.The glass temperature and the melting temperature of the polymer were almost the same as the poly(ether ether ketone)(PEEK).The crystalline behaviour of the polymer was studied bu X-ray diffraction method.The degree of crystallization was 30.7%.The polymer had five evident diffraction peak,which indicated the polymer had better crystalline behaviour.The poly(cyanoarylether) exhibited also excellent solvent resistance compared with the corresponding phenolphthalein polymer.This showed the molecular structure would affect on the solubility of the polymers.The crystal structune of the polymer was discussed by comparing with that of the poly(ether ether ketone).The poly(cyanoarylether) was the same as poly(ether ether ketone) to be attributed to orthorhombic system.The space unit parameter were computed.
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发布时间：2021-03-19 - 摘要：A series of diblock copolymers of styrene and 2 vinylpyridine have been synthesized successfully via sequential anionic polymerization.The results of GPC,FTIR,1H-NMR and 13C-NMR show that the products are diblock copolymers with high molecular weight 4.15×104 to 10.6×104 and narrow molecular weight distribution 1.19～1.66.The two phase structure of the copolymers is proved by the information obtained from DMA and DTA.
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发布时间：2021-03-19 - 摘要：Many new solvents were investigated for the copolymerization of CO with ethylene to prepare polyketones with small reactor experiments.The backbone and the end groups of the polyketones prepared in different solvents were analyzed with high resolution 1H NMR and 13C NMR techniques.The experimental results showed that,besides in methanol,in acetone,propionaldehyde,N,N dimethylformamide,N,N dimethylacetamide,glacial acetic acid,dimethylsulfoxide,palladium(Ⅱ)-bisphosphine catalyst also had high reactivity,especially in glacial acetic acid,the copolymerization could be performed without anions of strong acid.The experimental results also showed that suitable solvent should have suitable stability on central metal palladium(II) besides acting as diluent.End groups analysis showed that the copolymerization was initiated by insertion of ethylene into Pd-H bond in non-alcohol solvents,was mainly initiated bu insertion of CO into Pd-OR bond in alcohol solvents.
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发布时间：2021-03-19 - 摘要：The Nylon 6/montorillonite nanocomposites are successfully prepared through melt intercalation process.The crystallization behavior of nanocomposites is studied by means of WAXD and DSC.The results show that the nanocomposites have a crystal structure and crystallization behavior different from that of Nylon 6.The presence of clay in the nanocomposites increases the crystallization temperature of Nylon 6,narrows the width of the crystalline peak and induces γ crystalline form.Mechanical property testing shows that the nanocomposites is superior to Nylon 6 in terms of heat distortion temperature,tensile strength and modulus without sacrificing its impact strength.The performance improvemnt of the composite at low filler content is superior to that of conventional counterpart composites.This is due to the nanoscale effect and the strong interaction between Nylon 6 matrix and montmorillonite interface as revealing in X-ray diffraction,transmission electron microscopy and Molau testing.
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发布时间：2021-03-19 - 摘要：It was reported that living radical polymerization of styrene,methyl methacrylate,methyl acrylate was initiated at lower temperature using ethyl α bromobutyrate as an initiator and CuBr/2,2' bipyridine as a catalyst.MMA could undergo living free radical polymerization at 20℃.The “living” characteristics of the polymerization were studied.LowMw/Mn of the polymers (1.15～1.45) was obtained.The kinetic data of the three systems were calculated and the factors affecting the “living” characteristic of the polymerization were studied.Low Mw/Mn of the polymers (1.15～1.45) was obtained.The kinetic data of the three systems were calculayted and the factors affecting the "living" characteristic of the polymerization were discussed.
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发布时间：2021-03-19 - 摘要：The work disscussed the effect of structure of spherulite on properties of pure nylon 6 and Nylon 6/TPAE/Compatibilizer alloy by the experiment of changing the cooling velocity when shaping.First,melts of pure nylon 6 and Nylon 6/TPAE/Compatibilizer alloy were cooled rapidly and slowly on the condition of 4℃ water and 23℃ air respectively.Second,they were made into specimens.Then,specimens were carried on observation of structure of spherulite and dispersioin morphology and analyses of absorbing heat,meanwhile by PLM,SEM and DSC,carried on the experiment of tensile fracture and interface tearing. The results show;(1) Dispersion particles are well-distributed between interface and interior of spherulite or between lameller crystals.(2)The size of spherulit is greatly is greatly different when pure nylong 6 is cooled rapidly in 4℃ water.But that of spherulite is well-distributed when it is cooled slowly in 23℃ air.The comparison of them shows the latter speciment's size of spherulite is large and fracture strength is high,with decreasing deformation and energy of tensile fracture.(3) The size of spherulite is small but differs greatly when Nylon6/TPAE/A8200 alloy was cooled rapidly in 4℃ water,but that of spherulite is large and well-distributed in 23℃ air.The comparison of them shows the latter specimen's size of spherulite is large and fracture strength is high,with increasing the deformation and energy and energy of tensile fracture.(4) On the same cooling condition,the change trend of size of soherulite of pure nylon 6 and nylon 6/TPAE/Compatibilizer alloy is same,but that of properties of tensile freacture is oppsite.This a because slow cooling contributes to not only the formation of large spherulite but also the enhancement of adhesion strength of interface between the dispersed phase TPAE and successive phase nylon 6.On the other hand,the dispersion of tiny TPAE particle in the interface and interior of nylon 6 spherulite strengthens the deformation ability of spherulite,and enhances the strength deformation and energy of tenssile fracture. Pure nylon 6 has not these specific properties.Therefore,though the size of spherulite is one of factors which influence fracture properties of nylon6, the interface of spherulite,non-crystal stucture between lamellar crysrals,voiding of tiny elastic and adhesion strength of phase interface are main factors which influence fracture properties of nylon 6.
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发布时间：2021-03-19 - 摘要：Plastic materials for optical products are strongly required to exhibit high refractive index and low dispersion (with less chromatic aberration),and the most convenient and effective way is to introduce sulfur element into polymer structures.Therefor,2,2' mercaptoethyl sulfide (MES) dimethacrylate (MESDMA) and p phenylthioethyl thiolmethacrylate (MEPSMA) were synthesized by normal phase transfer catalysis (PTC) and special PTC reaction (dropping caustic solution),respectively.The double-bond containing monomers(MESDMA and MEPSMA) and their precursor thiols (MES and p-phenylthioethanethiol(MEPS) were characterized and corroborated by 1H-NMR and FTIR spectra.According to the analysis of 1H-NMR,the foreign substance in MES was caused by thiodiglycol (TDG),and it can not be eliminated by distillation of MES or TDG.Due to the results of monomer synthesis and polymerization,the little amount of foreign substance in MES has no disadvantageous affect,through quality control,the MES can be used directly.It was proved by 1H-NMR and FTIR spectra that the addition reaction between the mercapto of MEPS and the double bond in normal PTC condition leads to the failure of double-bond containing monomer (MEPSMA) synthesis.In the condition of special PTC reaction,the thiolate(RS-anion)of MEPS is just appeared following with the dropping of caustic solution,its amount in the organic layer maintains lower and it is more easily to react with MC,which is large amount and freely to move,not with MEPSMA,which is big volume and difficult to move,so MEPSMA can be successfully synthesized by this way.The special PTC reaction,i.e.dropping caustic solution not MC,is the best way to prepare double-bond containing monomers from thiols and MC in characterizations of light color,high purity and high yield,especially for those double-bond containing monomers with higher molecular weight and difficult to refine.MESDMA/MEPSMA transparent copolymer resins with refractive index higher than 1.625 were obtained bu casting the monomers and initiator into glass molds,polymerized in an oven according to a definite curing program.Some basic properties of the resins,e.g.refractive index,Abbe number,density and impact strength etc.are measured finally.
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发布时间：2021-03-19 - 摘要：Two kinds of poly (ethylene oxide) and poly (propylene oxide) diblock and triblock copolymers which have the same compositions but different block architecture have been synthesized in this work.The association properties of them were studied by fluorescence methods in aqueous solution.It was found that the copolymers with different block architecture have different properties.The triblock copolymer is easier to form micelles than the diblock copolymer in aqueous solution.But gelation is easier for the diblock copolymer than for the triblock copolymer.The results were explained and discussed preliminarily.
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发布时间：2021-03-19 - 摘要：In the copolymerization of CO2 and propylene oxide, the copolymers with designed molecular weight and OHfunctionality can be obtained by addition of certain regulators. The copolymerization was found slower than that without regulators. The regulation is recognized to be the chain transfer reaction between the active hydrogen and the active centers of the catalyst. Mechnism for this copolymerization was suggested and a rate equation was accordingly deduced. The transfer constants were determined for regulators such as H2O,1,4-butanediol,1,6-hexanediol,and 1,1,1-trimethanolpropane.Yields of the copolymerization in the presence of such regulators at various reaction time were calculated according to the developed principle.The results were consistent with the experimental data.
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发布时间：2021-03-19 - 摘要：Poly(styrene-co-maleic-anhydride)/titania hybrid material has been successfully prepared from styrene-maleic anhydride copolymer and tetrabutyl titanate(TBT) in the presence of a coupling agent 3-aminopropyltriethoxysilane(APTES) by in situ solgel process. It was observed that the gel time of sol-gel solution was influenced by the amount of APTES, as well as the sol fraction of hybrid materials. The covalent bonds between organic and inorganic phases was introduced by the aminolysis reaction of amino group with maleic anhydride units of copolymer to form a copolymer bearing trimethoxysilyl groups,which undergo hydrolytic polycondensation with TBT.The presence of absorption band at 1850cm-1,1790cm-1and 920cm-1 revealed the formation of carboxy and amide group as well as Si-O-Ti linkage in the resulting hybrid materials.The transmittances of resultant hybrids are about 80%.The thermogravity analysis (TGA) shows that the inital decomposition temperature of samples is affected by the content of TBT due to the condensation between residual Ti-OH and Ti-OBu of inorganic network.
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发布时间：2021-03-19
Research Article
- 摘要：A series of methacrylate monomers, such as 2,2,3,3-tetrafluoropropyl, acetoxyethyl, propionyloxyethy1,buthyloxyethyl,isobuthyloxyethyl,tertpentanoxythy1 and (2-glycidy1-ether) ethy1 methacrylate, were synthesized. Their homopolymers and copolymers with high molecular weight were obtained by radical polymerization. By measuring with light scattering and viscosity, the MarkHouwink equations of those homopolymers were determined. The group contribution method was used to calculate the values of index of refraction,dn/dc and parameters of Mark-Houwink equations of those homopolymers based on cohesive energy,molar volume and molar attraction constant.
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发布时间：2021-03-19 - 摘要：The effect of rubber particle dispersion on the toughnessmodulus relationship of polyvinyl chloride (PVC)/nitrile rubber (NBR) blends is studied. It is demonstrated that the pseudonetwork morphology is much more effective in the rubber toughening of PVC than that of welldispersed rubber particles. However, the rubber particle dispersion does not affect the tensile modulusrubber volume fraction relationship of the blends.The effect of rubber particle dispersion on the toughnessmodulus relationship of PVC/NBR blends are compared.It is concluded that the pseudonetwork morphology is very efficient in generating PVC/rubber blends simulataneously with high toughness and high stiffness.
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发布时间：2021-03-19 - 摘要：Two tetramethyldisiloxanediyl bridged binuclear titanocenes Cl2CpTiCp*(CH3)2SiOSi(CH3)2Cp*TiCpCl2(Cp*=substituted cyclopendienyl, R=H in catalyst A, R=Si(CH3)3 in catalyst B) have been synthesized by the reacting dilithium salts of Cp*(CH3)2SiOSi(CH3)2Cp* with CpTiCl3 in the yields of 42% and 51% respectively. Their catalysis behavior for the polymerization of ethylene under different conditions were investigated, and compared with mononuclear metallocene, cyclopentadienyl- titanium dichloride.The result showed that these two catalysts have a middle activity for ethylene polymerization.The MWD of the polyethylene were rather wide and the highest molecular weight was as high as 5.9×104g/mol.Furthermore,catalyst B exhibited unexpected temperature dependence for ethylene polymerization.
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发布时间：2021-03-19 - 摘要：A block copolymer containing terephthaloyl bis(4 oxybenzoyl) (triad) mesogen and polyether sulfone (PES)unit was synthesized by polycondensation of PES oligomer. terephthaloyl dichloride and 1.6-hexene bis(-p-hydroxy-benzoate). This obtained block copolymer was added into the blends of PESPoly(ethylene terephthalate)(PET)/Poly(-p- hydroxybenzoic acid)(PHB). Comparing the Tg and phase morphology of the blends with different component of the block copolymer, it was shown that this block copolymer could improve the compatibility of PES-PET/PHB.
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发布时间：2021-03-19 - 摘要：Cellulose is very rich in the world, so it's an important trend to develop new types of chelating cotton with high selectivity. In this paper, Phenylthiourea(PTU) of excellent selectivity for heavy metals has been grafted to the cotton cellulose by using indirect etherified method, Chelating cellulose Phenylthiourea is synthesized at last. The sorption behaviors of CC PTUresin for heavy metal ions were determined.
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发布时间：2021-03-19 - 摘要：Poly(bisphenolA phenylphosphonate)(PBPPP) was synthesized by melt polycondensation using phenylphosphonic dichloride(PPD) and bisphenol A(BPA). The relationships between inherent viscosities of PBPPP and reaction conditions such as temperature, time, ratios of monomers and the ways of addition were shown in the paper. The inherent viscosities of PBPPP increased with the increase of ratios of BPA/PPD, the reaction temperature and time, but they behaviored opposite varrations when the ratio of BPA/PPD, the reaction temperature and time,but they behaviored opposite varrations when the ratio of BPA/PPD, the reation temperature and the reaction time were beyond 1:0.990,280℃ and 4.5h,respectively.PBPPP products with an inherent viscosity of 0.37g/dL were obtained in the optimum conditions in which the ratio of monomers was 1:0.99(-OH/-Cl), the reaction temperature from 160℃ to 280℃ and the time 4.5h.The structures of PBPPP were characterized by FT-IR,1H-NMR,31P-NMR and elemental analysis.The thermal behavior was evaluated by DSC and TG. The thermal analysis indicated that the Tg of PBPPP was at 107℃ and PBPPP's starting loss weight at about 310℃.The LOI of PET containing 10wt% PBPPP was 28.0,which show that PBPPP can be used as flame retardants.
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发布时间：2021-03-19 - 摘要：The interaction of sodium dodecyl sulfate(SDS) with cationic polyelectrolyte derived from poly(4 vinyl- pyridine styrene) hes been investigated. It was found that there has been a narrow molar ratio region of SDS/cation at which the viscosity of aqueous solution rises suddenly due to the aggregation of the SDS attached on cationic polymer, then falls sharply as the SDS/cation ratio is beyond the region because of the deaggregation. At a suitable condition a reversible gelation was observed. A suggestion for explaining the specific phenomena was proposed.
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发布时间：2021-03-19 - 摘要：A series of itaconate monomers, e.g. 4 Methyl 1 (2 pyrrolidinonylethyl) itaconate (PyEMI), 4 i Propyl 1 (2 pyrrolidinonylethyl) itaconate (PyEPrI), 4 n Butyl 1 (2 pyrrolidinonylethyl) itaconate (PyEBuI),4 Benzyl 1 (2 pyrrlolidinonylethyl) itaconate (PyEBzI) and 4 (2 Phenylethyl) 1 (2 pyrrlolidinonylethyl) itaconate (PyEPhEI)) were synthesized by reaction of 1 (2 hydroxyethyl) 2 pyrrolidinone with corresponding itaconic monoester chlorides. They were polymerized by photo initiated free-radical polymerization.The properties of the monomers and polymers were characterized by GPC,DSC,TGA, swelling ratio and refractive indices.The molecular weights of the polymers may reach 1～2×104.The refractive indexes of P(PyEBzI),P(PyEPhEI) are larger then those of P(pYemi),P(PyEPrI) and P(PrEBuI).The EWC values of P(PyEBzI),P(PyEPhEI) are also higher than those of P(PyEPrI) and P(PyEBuI) but The EWC value of P(PyEMI) is up to 89%.The decomposition temperatures of P(PyEPrI) and P(PyEBzI), due to the steric hindrance effect.
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发布时间：2021-03-19
Research Bulletin
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