最新刊期
卷 ， 期 5 ， 1996
- 摘要：The Avrarra crystallization kinetic equation fitted by weighted least squaresmethod was investigated and the two weight expressions were derived. If the nonlinearAvrami equation was changed into the linear equation and only the transform ofthe vari-ance of error was considered,then the weight could be expressed asW1=[(1-a)ln(1-a)]2If the transform of the variance of error term arld the feature of DSC measurement wereconsidered simultaneously,then W2=[(1-a)ln(1-a)]2(d2a-dt2/da-dt)2The results calculated from poly(ethylene terephthalate)indicate that the weighted leastsquares methods are better than the general least squares method．
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发布时间：2021-03-19 - 摘要：The effect of the dispersion component of surface energy (yds) and the character of acid/base of natural rubber grafted acrylmide polymers on the property of anti-blood condensing was studied．The results showed that aboVe graft polymerwith lower value of yds(29.7 mJ/m2) and expressing a weak basic character possesseda better property of anti-blood condensing (time of contacting with blood：60 min,absorbancy：O.059) and had a very low absorbing character to blood platelet(absorbtion value：14.8±6.4/1000 μm2),Comparatively,the natural rubber was 0.038and 42.6±11.6
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发布时间：2021-03-19 - 摘要：Three diaryliodonium fluoroborates were prepared with an improvedmothed and their structures were characterized by IR,1H-NMR,UV and elemental analysis A photosensitive prepolymer,epoxypolysiloxane(EPS),was pre-pared by reaction of silicon oil containing hydrogen with functional epoxy compoundwith diaryliodonium fluoroborates as photoinitiators,the cationic photocuring processof epoxypolysiloxane(EPS)and the influence of phototinitiator's concentratlon,struc-ture and some promotors on EPS photocuring rates were studied．The results showed that epoxypolysiloxane (EPS) is highly photosensitive prepolymer,diaryliodoniumsare effective photoinitiators for EPS’s cationic photocuring,and Benzoin methvl ethercan promote the cationic photocuring process of epoxypolysiloxane(EPS)．
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发布时间：2021-03-19 - 摘要：Cross-linked polystyrene+supported polyethylene glycol and pyfidinium asbicenwal polymer-supported phase transfer catalyst was prepared by usingchloromethylated DVB-PS resin as supporter,on which PEG-400 and pyridine wereimmobilized successavely．The IR spectra of chloromethylated polystyrene resin,polystyrene-supported PEG-400 resin,polystyrene-supported pyridinium resin and the bicentral resinwere obtained and analyzed The catalytic activity of the three laters aspolymer-supported phase transfer catalyst was tested in the reaction of solid potassiumacetate with benzylbromide by GC analysis．It was found that the bicentral catalyst-Dolystyrene-supported PEG and pyridinium performed higher phase transfer catalytic ac-fivity than the monocentral polystyrene-supported PEG or polystyrene-supported pyfidinium.
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发布时间：2021-03-19 - 摘要：The number of reducing end of carboxymethylcellulose (CMC) produced in thedifferent solvents has been experimentally determined by potentiometry after completeenzymic degradation or acid hydrolysis．Parameters relating to the distribution of substituent along CMC chain,such as the average length of substituted or unsubstitutedanhydroglucose units (AGU),the percentage of monosubstituted or disubstituted units,etchave been calculated,and the resistance to acid of these CMC was studied．It shows thatthe solvents are dosely telated to this distribution of substituent．Also,the effect of differ-ent compositions of i—propanol/water on the distribution of substitufion of CMC hasbeen studied．When the content of i—propanol changed from 75％ to 95％,it was foundthat the degree of substitution of CMC increases,and that the uniformity of the distritufionof substitution iS better with the increasing concentration of i—propanol.
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发布时间：2021-03-19 - 摘要：The structure of P—hydroxybenzoic acid and 2—hyaroxy—6—naphthoic acidcopolyester(HBA/HNA) fiber was studied by means of wide-angle X-ray diffraction and differential scanning calorimetery．Highly oriented HBA／HNA fibers were annealed at100～300℃ for 40h The results showed that the cocrystallization of the comonomerstook place in spite of their random distribution along the molecular chain of the HBA／HNA copolyester fibers．The unit dimensions of the fibers show a change with annealedtemperature,which can be associated with a transformation from an orthorhombic tomonoclinic unit cell．
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发布时间：2021-03-19 - 摘要：X—ray diffraction as well as the transmission technigue have been used to studynine types of poly (ethylene terephthalate) industrial filaments made in various domesticand overseas factories．X—ray diffraction patterns of crystal planes 010,110,100 in equa-tor line and 105 in meridian line ate measured．By means of peak—separating techniquethe average cross-sectional area,the average length and the average volume of the crystalgrains are calculated．The result shows the obvious differences among the various filaments．Primary knowledge,average crystallite size was concerned with shrinkage of fibers.
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发布时间：2021-03-19 - 摘要：A series of block-copolymers based on aminopropyl-terminatedpolydimethylsiloxane or polyurea modified polysiloxane oligomers,4,4'-methylenediphenylenediisocyanate and 1,4'-Bis (2-hydroxythyl) piperazine was synthesized．Ionization was accomplished by using iodoethane and γ-propane sultone respectively．All of the samples are transparent and exhibit thermoplastic mechanical properties ina wide range of temperature The morphology of these samples was studied in detailby using FT-IR,DSC and DMTA etc．It Was found that the incorporation of polyurea chain into polydimethylsiloxane soft segments increased the phase mixingand resulted in higher Young’S modules,ultimate tensile strength and elongation thanthe polydimethylsiloxane polyurea-urethane system.
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发布时间：2021-03-19 - 摘要：It is proved clearly by using H-H COSY that there is the three-substitutedbond in the end of polycyclic sequences of cyclized cis-l,4 polybutadiene．On the other hand,a little of trans-l,4 and l,2-units of polybutadiene are comprised in the residue linear chain of cyclized cisl-,4 polybutadiene as shown in its 13C NMRspectrum Based on information provided by H-H COSY,assignment of thehigh-resolution 1H NMR spectrum of cyclized cis-l,4 polybutadiene is obtainedfinally．In order to get the degree of cyclization(X)and the cyclicity(Y) of cyclizedcis-1,4 polybutadiene two parameters P and Q are defined．In the same time．the relationship between X,Y and P,Q are discussed and the fortnulas calculated X and Y are provided．The method proposed in this paper is satisfactory to investigation of its microstructure and physical,physical-chemical properties．
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发布时间：2021-03-19 - 摘要：Because methyl methacrylate (MMA) is of some hydrophilicity,the radicaldesorption must be taken into account in the case of kinetic calculation and modeling of emulsion polymerization. In the present paper,based on kinetic study on emulsionpolymerization of MMA,a multivariate equation for calculating radical desorptionrate constant,κo,was derived. The variation in κo along with the process of emulsionpolymerization of MMA was studied．The effect of various factors on radicaldesorption was analyzed. The calculation results denote that κo is a nlnction of notonly monomer conversion,but also the concentration of initiator,concentmtion of emulsifier reaction temperarure and phase ratio．Besides,the inherent reasons for these factors and variation were discussed．
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发布时间：2021-03-19 - 摘要：The plasma polymerization of aniline in a capacitivity coupled of glow discharge was described and suitable conditions for plasma polymerization were found.The polymer structure was inverstigated by using FTIR,X-ray diffraction,electron diffraction and determination of contact angle.The results of electrical conductivity determination showed that the polymer has semi-conductive prooerty.
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发布时间：2021-03-19 - 摘要：Sequential block copolymerizations of styrene with propylene were carriedout with MgCl2-supported TiCl4 catalyst modified with rare earth compound of NdClx (OR)y (called SN catalyst) which was developed in our laboratory．Afterfractionating by successive solvent extraction with suitable solvents,the remainingcopolymer was subjected to extensive molecular and morphological characterization with 13C-NMR,WAXD,DSC,DMA,TEM．The results of these experiments indi-cate that the purified polymers are a crystalline diblock copolymer of isotacticpolystyrene and isotactic polypropylene,with 15～85 mol％styrene-unit content．The diblock copolymer has superior mechanical and thermal properties to their corre-sponding homopolymers．
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发布时间：2021-03-19 - 摘要：Banded texture was decorated on oriented films of 4-hydroxybenzoic acid-2-hydroxy-6-naphthoic acid copolymer by annealing．The fibrils of three levels,Which were macrofibrils of several tens micron in diameter,fibrils feW micron and microfibrils about 0.3 micron,were observed simultaneously with banded texture usingpolarized microscope．After annealing,fibrils in different levels relaxed to differentmorphology．Macrofibrils still oriented along shear direction,but fibrils relaxed to helical form,and microfibrils relaxed to waveform therefore the banded texture canbe seen．The smaller the diameter of fibrils was,the more easily the fibrils relaxed．Ori the other hand,the banded texture decoration of annealed unoriented filmsrevealed directly the distribution of directors within and out of domains and thevariation of directors on boundaries．The formation of banded texture iS explained byslow effect of constricting elastic force of macromoleeules on relaxation duringannealing．
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发布时间：2021-03-19 - 摘要：The reaction of silicon-nitrogen compounds with hydroxyl-terminatedsilicone oil in the absence of solvent is discussed Studies of reaction kinetics showthat the reaction is of second order and the activation energy (Ea) is about44 kJ／mol．The reaction rate increases with the increase of nitrogen content,the bigratio of N to Si and the large tensility of cyclosiliazane．The introduction of phenyl to silicon results in the decrease in the reaction rate The effect of temperature on thereaction rate iS also discussed．
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发布时间：2021-03-19 - 摘要：Based on surface properties and molecular structure characteristics of polypropylene (PP)／ethylene-propylene-diene monomer rubber (EPDM)／talcpowder three-phase composites,inorganic filler was forced into rubber phase to form elastic interfacial phase between PP matrix and filler during the melt processingby surface treatment of fillers and the addition of reactive components-Effects of the formed elastic interfacial phase on processing properties and performances werestudied by means of scanning electron microscopy (SEM),dynamic mechanicalanalysis (DMA),chemical analysis,etc．The result shows that the formed elasticinterfacial phase can promote filler in three-phase composites to achieve the condition of rigid particle toughening polymer．Above-mentioned three-phasecomposites have high tensile strength (σy) and high flexural modulus (Ey)．
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发布时间：2021-03-19
Research Article
- 摘要：P-N,N-Dimethylaminostyrene (DMAS) was synthesized through Wittigreaction and polymerized using AIBN as an initiator．The charge transfer complexformed between monomeric and polymeric DMAS with electron acceptors such asunsaturated nitriles and acrylates as well as C60 Was verified by fluorescence method．A distinct curvature appearing in the Stern-Volmer plot of P (DMAS) quenched by(C60 proved that the CTC was formed in the ground state．The measurement of oxidation-reduction potential and fluorescence behavior of monomeric and polymeric DMASwould contribute to the conformation of monomer and polymer in solution．
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发布时间：2021-03-19 - 摘要：Polyamides containing pyrazolone in the main chain as chelate resins (PPZ) wereperpared by the condensation polymerization of 1,10-diaminodecane with bispyrazolonecarboxylic ester (PZ) The adsorption ability of PPZ for metal ions were inversfigated.
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发布时间：2021-03-19 - 摘要：A double-chain amphiphilic amino acid,S-[1-carboxy-2-([N-(1,2-bisoctadecyloxycarbonyl)ethyl]carbamoyl) ethyl]cysteine (Asp18-M-Cys) was synthesizedby Michael addition of cysteine with maleic acid derivative．The stable liposome formedfrom Aspl8-M-Cys in buffer solutions of different pH(6.5,7.4,8.5) was confirmed bydectron microscopy．When co-dispersed with water soluble N-Cydohexyl-N’-[β-(N-methyl-morpholino)ethyl]carbodiimide-p-toluenesulfonate (wsD),Aspl8-M-Cyscould be polymerized as stable liposomes and the polymerization was followed by FT-IR．GPC and DSC．
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发布时间：2021-03-19 - 摘要：The inlluence of polymerization time on the selective amomc polymerization of α C=C double bond in 2,3-epoxypropyl methacrylate (EPMA) has been investigated．Meanwhile．the block copolymer of EPMA and methyl methacrylate (MMA)has alsobeen prepared．It is found that with the polymerization proceeding,the conversion of EPMA was going up,Mn becoming larger,but the molecular wdght distribution did notchange．The poly (EPMA)s produced are of very narrow molecular weight distributions(Mn/Mn≤1．02) and carry an epoxy group on their each repeating unit quantitatively．The block copolymers also possess narrow molecular weight distributions and the massratio of MMA to EPMA determined by NMR measurement is in good agreement、withdesigned value．
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发布时间：2021-03-19 - 摘要：Thin films of poly (methyl methacrylate)(PMMA) were prepared by caslang2wt％methvlelle chloride solution．These films were annealed at 70℃ for different timesrespectively．The glass transition,the polymer crazing and the mechanical properlies of annealed PMMA films were studied. The results show that the craze fibril stability,sIrelching stress and extention ratio at break decrease and the entllalpy endo-peak on the DSC curve shiftstoward highel temperature as the annealing time fmcreases. It means that the physical aging time strongly affects the condensed entanglement of macromolecularchains in PMMA films．
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发布时间：2021-03-19 - 摘要：The direct counting method of the chain configurations has been proposedfor calculating the thermodynamic quantities of a single self-avoiding walk chainwith the neighbour interaction on a simple cubic lattice The configurational entropy of the chain lengths 10～18,the energy and the average number of contact betweennonconnective segments VS．the energy of one contact ∧ε have been calculated．It isshown from the results that the maximum of the configurational entropy of the chainoccurs at the athermal case．In the good solution the chain coil becomes loose and the entropy tends to a finite value；in the poor solution the chain coil becomes verydense and the entropy decreases drastically．
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发布时间：2021-03-19 - 摘要：In order tO synthesize telechelic polyisobutylene,the controllable terminationis usually required This paper reported the reaction of 1.1-diphenyl ethylene(DPE)with polyisobutylene(PIB) cation．It was found that DPE can quickly react with PIBcation at low temperature and form more stable 1.1-diphenyl alkyl cation．The lowtemperature is favorable for capping reaction,because the reaction is then reversible．The ratio of DPE to initiator have no great influence on the reaction．Theunsymmetric telechelic PIB with double bond completely at the chain end wasobtained．
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发布时间：2021-03-19 - 摘要：Several rare earth compounds have been investigated as addtive for the methanol carbonylation. The effects of different rare earth compounds, Rh/Mmolarratio,time on carbonylation were investigated.It was found that catalyst activity of different rare earth compounds is as follow:Ce>Nd>La,and the optium Rh/Ndmolar ratio of carbonylation reaction is 1:0.9.
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发布时间：2021-03-19
Research Bulletin
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