最新刊期
卷 ， 期 5 ， 1984
- 摘要：The structure and deformation eharacteristics of PS film craze in pregnant．gro-wth．mature and failure process were studied by transmission electron microcopy (TEM)．It is presumed that the fine white lines extended from craze tip along craze propagation direction are resulted from the tearing of PS molecular chain under ten-sile stress field．According to Our experimental results．the authours proposed the cold-drawn mechanism and transverse constraction of craze matter during plastic de-formation．It was observed that the primary craze matter broke in accordance with the“tearing cloth” model and the crack．tip crazes have shape described by the DugdMe model．It was discoverd by TEM that the craze thickness increased in two ways．by the elongation of primary craze matter and by the converting of PS moleculers on craze／matrix polymer interface into craze，proposed by E．J．Kramer．
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发布时间：2021-03-19 - 摘要：The bulk polymerization of methyl methacrylate which were carried out in a metallic dilatometer and DSC have been studied over the complete course of the reaction. An attempt was made to quantitatively express the relation on the onset of gel effect and the final conversion with polymerization conditions such as temperature, kinds and concentration of initiators. It was demonstrated further that the final conversion of polymerization in homogeneous ideal systems is only dependent on reaction temperature.
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发布时间：2021-03-19 - 摘要：Crosslinked aceto polystyrene was obtained by reacting crosslinked polystyrene and acetic anhydride with aluminium trichloride as catalyst. The effects of the solvent, reaction temperature, reaction time, amount of reagents and catalyst on the acetylation were investigated. Reaction of aceto polystyrene with phosphorus trichloride followed by treatment with glacial acetic acld and hydrolysis by water yields α-hydroxy phosphonic resin. Solvents, reaction temperature and time affect the phosphorylation.
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发布时间：2021-03-19 - 摘要：In the presence of iso-octanol or 2-ethyl butanol as a porogenic agent, a series of macroretieular styrene-divinylbenzene copolymers were synthesized. By measuring the porosity, surface area etc. of the copolymers, the main factors which affect the physical structure were discussed. The copolymer after acetylation and phosphonylation can react with dibutyl amine to yield the corresponding dibutylamidophosphate resin. Factors influencing the reaction between the crosslinked polystyrene phosphonic chloride and dibutylamine were studied. The changes in the physical structure of the copolymer after the reaction were investigated.
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发布时间：2021-03-19 - 摘要：The effect of computational interval AV, effective figure of experimental data on accuracy and precision of peak spreading correction is examined by model funtion in this paper. Stable solution ranges corresponding difference AV have been found which provide the base for selecting optimum colculating condition.
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发布时间：2021-03-19 - 摘要：A new type of neodymium complex was synthesized. The analytical results indicated that this compound is (CF3COO)2NdCl-EtOH. A homogeneous catalyst system was obtained from this complex combined with triethylaluminium and gave polybuta-diene containing cis-content from 78 to 98%.
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发布时间：2021-03-19 - 摘要：A new bimetallic crystalline lanthanide complex which is active for polymerization of dienes was isolated from the homogeneous solution prepared by the reaction of (CF3COO)2NdCl·EtOH with Et3Al.A bridged structure of the lanthanide complex was proposed.
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发布时间：2021-03-19 - 摘要：Four γ-substituted-propylcyclotetrasiloxanes have been synthesized. Emulsion co-polymerizations of these cyclosiloxanes with octamethylcyclotetrasiloxane have been carried out in cationic and in anionic emulsion systems. Via these reactions, stable emulsions of organosilicon polymers which contain carbonfuctional groups such as γ-hydroxypropyl,γ-acetoxypropyl, γ-chloropropyl have been obtained.The effects of temperature, catalyst and the amount of γ-substituted-propylcyclo-tetrasiloxanes in the emulsion copolymerizations have been studied.
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发布时间：2021-03-19 - 摘要：The thermodynamic properties of a series of sulfonate resins with interpenetrating polymer networks (SRIPN) were studied and the ΔG0, ΔH0, ΔS0, of ion exchange reactions for SRIPN which have various degree of crosslinking and various weight ratio between two networks of beads were measured. The interrelation between the thermodynamic properties and structure of SBIPN was generalized. Through the study of the relation between water regain and equivalent fraction of the replacing ion on resin phase the concept of integral water regain (IWR) has been put forward. When SRIPN was applied to the ion elution chromatography of KCl, NaCl, CaCl2,MgCl2 mixture,the efficiency of separation was far better than that with SGSR.
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发布时间：2021-03-19
Research Article
- 摘要：The samples of some typical alkyd resins with various oil lengths and formula-tions，which are the products in different stages of esterification during the manufac-ture of alkyd resin，were characterized by HPGPC，VPO，wet analysis，Gardner’s tube viscosity and high temperature viscosity． It has been shown that the increase of Mw is much faster than that of Mn and the MWD broaben graduately．The Mn Value predicated in theory is larger than that mea-sused by VPO．The nH of the high concentration solution of the alkyd resins at high temp．are correlated to the Mw by the Mark-Houwink equation．For the alkyd resin end-products，which was synthesized by the alcoholysis of vegetable oil，with various oil lengths and formulations, the order of polydispertive index d is as follow：short oil lengthw and d．
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发布时间：2021-03-19 - 摘要：With Friedel-Crafts reagents,, the polymerization of a series of aliphatic nitriles, including acetonitrile, propionitrile, n-valeronitrile, n-oenantionitrile and phenylaceto-nitrile, has been studied. The results show that the polymerization ability of these nitriles decreases with the increase of aliphatic chain-length. Polynitriles are a new type of conjugated polymer with the following chain structure: [(R)C = N]p, R = CH3, C2H5,n-C4H9, n-C6H13, C6H5CH2. The complexes of nitriles with metal halides, such as BF3, TiCl4 ets., play an important role in the polymerization mechanism. The semi-conductivety and heat resistance of polynitriles were determined.
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发布时间：2021-03-19 - 摘要：In order to check the effect of structure of VPO on the instrument calibration factor two kinds of VPO, one with stand-up type thermistor and the other with hang-down type, have been calibrated with a number of identical standard samples. Including nine organic compounds, with molecular weight ranging from 178 to 1089 and six polystyrene samples from 2.82×103 to 4.42×104. The results show that the calibration factor of the instrument with hang-down thermistors is dependent on the molecular weight of solute while that of the instrument of stand-up thermistors is inde-pendent on the molecular weight of solute. Some factors including the concentration and viscosity of the solution the quantity and shape of the liquid on the thermistors have been discussed.
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发布时间：2021-03-19 - 摘要：Allyl halide or benzyl chloride can greatly regulate the molecular weight of polymer during the polymerization of butadiene in hydrogenated gasoline with PeCl3-(i-C4H9)3Al-phen catalyst system. It was found that allyl chloride is the most effective regulator of molecular .weight among them. The [17] of polybutadiene can be lowered from over 1.0 M3/kg to less than 0.4 M3/kg by the addition of allyl chloride, while the polymerization keeps high yield. Polybutadiene rubber with mid-vinyl structure was obtained and it has good properties.
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发布时间：2021-03-19 - 摘要：The copolymer of 1-(acetylsalicylyloxy) ethyl methacrylate (HEMA-ASA) with me-thacrylic acid (MA) has been prepared and the hydrolysis of this copolymer in dio-xane-H2O either in acidic or in alkaline medium, at 60℃ or 37℃ have been investigated. It was found that the chief product of hydrolysis is always aspirin with minor amount of salicylic acid. Due to its neighbouring effect, the hydrolysis rate of (HEMA-ASA)-MA copolymer markedly depends on its composition and the pH value of hydrolysis medium, i.e. the hydrolysis rate increases with increasing the mole frac-tion of MA in copolymer and the pH value of hydrolysis medium.
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发布时间：2021-03-19 - 摘要：In this work the thermal degradetion of poly(styrene sulfone) has been studied by differential scanning calorimeter (DSC) and thermogravimetric analyzer (TGA). Poly-(styrene sulfone) shows a two-step degradation mechanism, the initial degradation occuring in the temperature range 120-200℃ and major degradation taking place at higher temperature. Isothermal degradation of poly(styrene sulfone) .has also been studied. Above 270 ℃ the kinetics of the thermal degradation are first order with an activation energ of 14 KCal/mol.
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发布时间：2021-03-19
Research Bulletin
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