最新刊期
卷 ， 期 1 ， 1993
- 摘要：A new kinetic equation of non-isothermal crystallization was derived by combining Av-rami and Ozawa equations. More crystallizatic informations can be obtained from the new equation. The kinetics of non-isothermal crystallization of poly(ethylene oxide) (PEO)/poly (hydroxy ether) of bisphenol A (PBHE) blends have been investigated by using differential scanning calorimetry, and the experimental results analysed showed agreements with the new kinetic equation.
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发布时间：2021-03-19 - 摘要：The effect of micelles on nucleation in the crystallization process of dilute poly(tetrahy-drofuran-b-methyl methacrylate) diblock copolymer/tetrahydrofuran homopolymer, dilute po-ly(ethylene oxide-styrene-ethylene oxide) triblock copolymer/ethylene oxide homopolymer solutions has been studied. The results show that nucleation behavior in these solutions is mainly dependent on the relative crystalline ability of the block copolymer and homopolymer, and the compatibility of the blends.
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发布时间：2021-03-19 - 摘要：The interlaminar fatigue crack growth behavior in a continuous carbon fiber reinforced poly(phenylene ether ketone) composite is studied. Experiments are conducted on double cantilever beam(DCB) specimens under mode I lo d controlled cyclic loading with a ratio of maximum to minimum load of 0.5. The delamina ion growth rate data are correlated with the corresponding maximum strain energy release rate by a power law. The resistance curve phenomenon is also found in the fatigue tests. The results of present study are discussed.
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发布时间：2021-03-19 - 摘要：The effect of quantenary ammonium salts(QAS) on the reaction speed and structure of the product of dehydrochlorinated PVC (polyvinylchloride) and the relationship of dehydrochlo-rination reaction with temperature and time were studied by means of dehydrochlorination of PVC-QAS film in the solid phase. Butyl-ammonium salts (BAS) is found better than ethyl-ammonium salts (EAS) in catalytic property. As a result of experiments, the catalytic mechanism of the decomposition of QAS into tertiary amine was proposed.
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发布时间：2021-03-19 - 摘要：Polystyrene macromers containing vinylphenylethyl end group have been synthesized by using commercial divinylbenzene (a mixture of p-DVB, m-DVB, p-EVB and m-EVB) as capping reagent reacting with polystyryl lithium in the presence of polar additive THF. The influences of capping reaction time, temperature, MW of PSt , and the amount of capping reagent as well as THF used upon the efficiency of this synthesis were examined and discussed. The characterization of these macromers obtained showed that their MWs approximately equal to the values designed,MWDs were narrow enough,the percentage of dimerization of macro-mers were less than 10% and the average numbers of pendent double bonds per macromer mole-cule were between 0.9 and 1.1.
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发布时间：2021-03-19 - 摘要：Hydrophobically modified (co) poly(alkylmethyldiallylammonium bromides) are novel types of polysoaps. Their structure and the composition of the copolymers were studied quantitatively by NMR techniques. The results indicate that NMR spectroscopy is a useful tool for the structural assignment of those copolymers which possess similar chemical structures and properties of the monomeric units.
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发布时间：2021-03-19 - 摘要：Permeation of SO2, N2 and separation of SO2-N2 mixed gas through functional polymer membrane of poly (vinyl alcohol) modified with propyl vinyl sulfoxide have been studied. The results show that the membrane possess high permselectivity for SO, and the permeability of SO2 increases with the increase of the sulfoxide content in polymer. Through the membrane with 25 mol % sulfoxide content, SO2 in SO2-N2 mixed gas can be enriched from 1.54% to 78.8% by one single pass.
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发布时间：2021-03-19 - 摘要：Poly foligo(oxyethylene) methacrylate] and poly(methacryloyl hexylsulfonic acid lithium) were successfully synthesized, from which the blends with single-Li+-ionic conduction were prepared. The Li+-ionic conductivity was deeply influenced by the compatibility, composition and temperature of the blends. The results show that the better the compatibility of the blends, the higher the conductivity. Li+Monic migration in the blend occurs mainly in amorphour regions and accelerates with increasing segmental motion of the matrix polymers. An optimum Li+-ionic conductivity of 5.3×10-7S/cm at 25℃ was observed for the homogeneous blend PMEO18/P(0.5SHMLi-0.5HEMA) with O/L:=70.
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发布时间：2021-03-19 - 摘要：The analysis method previously proposed has been developed to determine two activation energies and stress relaxation modulus for two-phase polymers by using a parallel model of two thermorheologically simple materials as the viscoelastic model of two-phase polymers. By this method the activation energies of relaxation processes around 150℃ and 70℃ were found to be 71.9 and 117.5 kcal/mol respectively for PET/70 PHB copolymer. The latter value agrees with that reported in literature for PET/60 PHB copolymer for the same relaxation pro-cess. Additionally, the ten-second relaxation m duli at various temperatures for PET/70PHB have been calculated,the result is consistent wih that measured by experiment.
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发布时间：2021-03-19 - 摘要：Effects of physical ageing on glass transition of phenolphthalein polyaryletherketone (PEK-C), phenolphthalein polyarylethersulfone (PES-C) and their blends and composites have been studied by differential scanning calorimetry (DSC). As the ageing time increases, the values of Tg, the peak temperature (Tmax), the peak height (△Cp max) and enthalpy (△H) of the enthalpy relaxation process increase, △H is proportional to 1gt. The ageing behaviour remained unaffected by addition of carbon black and short carbonfiber,but reactive oligomer ace-tylene-terminated sulfone (ATS) restricted the ageing process remarkably. It is easy to deter-mine the compability of multiphase systemsby the physical ageing at temperature below Tg.The results show that PEK-C/PSF blend is a compatible system and PEKC/PES-C is a par tially compatible system.
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发布时间：2021-03-19 - 摘要：A series of segmented polyether polyesters was prepared by solution polycondensation of terephthalic chloride, hydroquinone, 1,6-hexanediol and polytetramethylene glycol (PTMG). The anisotropy of melts was observed through the polarizing microscope, such as the melt of copolyester based on PTMG of molecular weight of 2,000 with a mesogen content of 21.2 wt-%(37.5 mol-%) showed anisotropy in a wide liquid crystalline temperature range of 65° and beyond 350℃, 1H-NMR studies revealed that all the products segmented with long polyether blocks have microsturcture of polyester block sequence distribution.
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发布时间：2021-03-19 - 摘要：The formation of polyisocyanurate-oxazolidone(PISOX) has been systematically studied The influences of the reaction temperature and the ratio of isocynate and epoxy to the gene ration of oxazolidone(OX) and isocyanurate(IS) rings in the formation of PISOX were quanti fatively investigated by means of in-situ infrared spectroscopy. It is found that low tempera ture is suitable to the generation of IS ring and high temperature is favorable to the generatioi of OX ring. At higher temperature IS ring may open and transform into OX ring with epoxy group. The structure of PISOX is mainly deterrined by the ratio of isocynate and epoxy and also the curing technology.
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发布时间：2021-03-19 - 摘要：The orientation behaviour of molecular chains of hard elastic polypropylene(HEPP) film was investigated on the uniaxial stretching by polarized IR Vibration-Mechanical Spectrosco-py. It was found that there are three components in the IR spectrum between 1130 cm-1 and 1190 cm-1. The orientation behaviour was measured using second derivative, deconvolution, curve-fitting programs and IR differencial spectra technology by computer. The bands at 1167 cm-1 and 1152 cm-1 may be related to the crytal conformation of HEPP long and short spi-ral chains respectively. The dichroism change of 1167 cm-1 band to different draw ratio is in agreement with 998 cm-1 crystal band on polarized IR spectra. A new band at 1159 cm-1 can be assigned to the amorphous hand.
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发布时间：2021-03-19 - 摘要：The contents of diferent structural deftects of five PVC samples，obtained by polymeri-zation at monomer unsaturation vapor pressure，and five commercial PVC samples were deter-mined．The total number of double bonds(C=CT) and labile chlorine atoms (ClL) were deter mined by bromine addition and phenolysis methods，respectively．The determination of inter-nal double bonds (C=Cint) and isolated doubl bonds(C=Ciso) was carried out by means of ozonlysis and FTIR methods．It was found tha：the dehvdrochlorination rates of PVC samples depended linearly on the contentof ClL，C=CT and (C=C)lso，respectively．In addition，the con-tents of these three structural defects were all correlated linearly with 1／Mn，so most parts of them would be the same defect——terminal allyl chlorine．Therefore，the main source of thermal dehydrochlorination of PVC could be attributed to the presence of terminal allyl chlorine groups．A mechanism．that in the presence of HCl as eatalyst the terminal allyl chlorine can be isomerized into internal allyl chlorine．was proposed to explain the main role of terminal allyl chlorine in the thermal dehvdrochlorination of PVC．
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发布时间：2021-03-19 - 摘要：The surface properties of untreated, silane-treated and titamate-treated Al(OH)3 filler were determined by Inverse Gas Chromatography (IGC). The rheological behavior and dispersion of A1(OH)3 in polypropylene matrix war investigated by Brabender plasticorder and Scanning Electronic Microscopy, respectively. The results show that the surface properties of Al(OH)s have important in fluence on the dispersion of Al(OH)3 in polypropylene matrix.
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发布时间：2021-03-19
Research Article
- 摘要：The effect of composition on the dynamic and macroscopic mechanical properties of EVA/PVC blends have been investigated. The results suggest that a semicompatibility exists between EVA (48 Wt% VAc) and PVC in the polyblend. The phase inversion occurs and over the range of EVA volume fractions from 18% to 80% both phase are co-continuous and where several properties will change very rapidly withcomposition. The calculated curve by using a combination of upper and lower bounds of Halpin-Tsai-Nielsen equation and logarithmic rule of mixtures fits the experimental data very well. The strengths reduce only slightly,the im-pact strength,however,can be improved greatly at about 6-8% of EVA.
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发布时间：2021-03-19 - 摘要：The derivatives of natural polymer chitin and chitosan：sodium salt of carboxymethyl-chitin and chitosan acetate，were examined as the protective polymers for the formation of the precious metal colloids．In the presence of carboxymethylchitin or chkosan acetate，stable me-tallic colloids of palladium，rhodium，ruthenium，platinum silver and gold were formed in a methanol-water solvent system．Particularly，TEM measurements illustrate that the narrowly dis-persed metallic colloids with fine particle size can be formed in the case of palladium，rhodium or ruthenium carboxymethylchitin or chitosan acetate systems．That is in carboxymethylchitin protective system，palladium sol is mostly dis,ributed in the range of 4.0—5.0 nm with an ave-rage diameter of 4.6 nm and rhodium sol or ruthenium sol is in 3.5—4.5 nm wkh an average diameter of 4.0 nm or in 3.0--3.5 nm with an average diameter of 3.2 nm， respectively；in chitosan acetate protective system，rhodium sol is in 4.0—5.0 am with an average diameter of 4.6 nm．Palladium，rhodium and platinum sols were tested as catalysts for the partial hydro-genation of 1，3-cyclooctadiene and showed quite a good activity as well as selectivity．
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发布时间：2021-03-19 - 摘要：The N-substituted polyacrylamide containing aclicyclic amino rings，such as：poly-N-acryloyl-N’-methylpiperazine，poly-N-acryloyl-morpholine，poly-N-acryloyl-pyrrolidone，poly-N-acryloyl-piperidine，were examined as the protective polymers for the formation of the pre-cious metal colloids．It was found that in the presence of poly-N-acryloyl-morpholine stable metallic colloids with fine particle size and narrow dispersion of palladium，rhodium，plati-num，ruthenium and silver were formed by means of alcohol reduction in a methanol-water mixed solvent system．TEM measurements illustrated that in poly-N-acryloyl-N’-methylpipe-razine protective system，palladium colloid was mostly distributed in the range of 1.5—2.0 nm wkh an average diameter of 1.6 nm；in poly-N-acryloyl-morpholine protective system，palla-dium colloid was in the range of 2.0—3.0 nm with an average diameter of 2.5 nm，rhodium colloid was in the range of 1.6—2.5 nm with an average diameter of 2.3 am．Palladium，pla-tinum and rhodium colloids formed were also surveyed as catalysts for hydrogenation of cy-clooctadiene．
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发布时间：2021-03-19 - 摘要：2-N-Pyrrolidonoethyl acrylate(PyEA) and 2-N-pyrrolidonoethyl methacrylate (PyEMA) were synthesized by reaction of N-2-hydroxyechyl pyrrolidone with corresponding acryloyl chlorides in the presence of triethylamine. The polymerization of PyEA, PyEMA were carried out at 40℃, using N,N-dimethylaminoethyl methacrylate(DMAEMA)-potassium persulfate (KPS) system as an initiator. Kinetic study showed that the rate equation of polymerization (Rp) could be expressed:Rp = Kp[DMAEMA]0.5[KPS]0.5[PyEA] orRp= Kp[DMAEMA]0.5[KPS]0.5[PyEMA] The overall activation energy for the polymerization was estimated to be 44.9 KJ/MOL,52.7 KJ/mol for PyEA or Py EMA respectively.
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发布时间：2021-03-19 - 摘要：With the addition of a thermotropic liquid crystalline polymer (TLCP), PHB/PET (60/ 40), glass fiber/polypropylene was melt blended and extruded. The decrease of apparent viscosity of melts , the preferred orientation of glass fibers in polypropylene matrix and the enhanced tensile properties of extrudates indicate that processability, structure and properties of glass fiber reinforced polypropylene have been improved by the matched TLCP.
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发布时间：2021-03-19 - 摘要：Four halogen-containing compounds，decatbromodiphenyloxide (DBDPO)， chlorinated paraffin-70(Cl-70)，polyvinylchloride(PVC) and chlorinated polyethylene(CPE) were conbi-ned with antimony trioxide(Sb2O3,) to constitu e flame-retardents of polyethylene．DSC and TG investigations show that conbustion of PE is thermal oxygenolysis process through free ra-dical reaction．Halogen-containing compounds decompose and release HX，which reacts with Sb2O3 to give SbX3，before PE burning．These sabstances can retard the conbustion by catching free radicals．△Td，temperature difference betw．en thermal oxygenolysis of PE and decompo-sition of halogen-containing compound，is defined to evaluate the efficiency of the flame-re-tardent．Retardents with proper values of △Td have higher efficiency than those wizh too large or minus values．Among four compounds used in this paper，DBDPO and Cl-70 are effective flame-retardents, while PVC and CPE are of lover efficiency．
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发布时间：2021-03-19 - 摘要：N-(p-methylphenyl) maleimide (PMPMI) was synthesized from the reaction of maleic anhydride with p-methylaniline via two steps processes. Radical polymerization of PMPMI using AIBN as an initiator or initiated with N,N-dimethyl-p-toluidine (DMT) under UV light irradiation have been investigated. Copolymerizations of methyl acrylate (MA), methyl me-thacrylate (MMA) with PMPMI were carried out in THF and cyclohexanone respectively. It was found that the molecular weights of the polymers and copolymers obtained from the cyclo hexanone were always greater than that of from THF. The monomer reactivity ratios were cal-culated.
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发布时间：2021-03-19
Research Bulletin
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