最新刊期
卷 ， 期 5 ， 1985
- 摘要：The acoustic emission event and its distribution in amplitude, broad, ring-down count, and dislocation during continuous and repeated loading of single edge notched PS sheet were measured. It was convinced that the acoustic emission of samples during extension came from the deformation, rupture, and propagation of crack-tip craze. The majority of the total ring-down count during experiment was contributed by the subc-ritical and unstable crack propagation of pre-cut crack. The Kaiser effect of acoustic emission was observed during repeated loading.
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发布时间：2021-03-19 - 摘要：1，1，5，5-tetrachloro-1，5-dimethyl-3，3-diphenyltrisiloxane (A) and 1，1，5，5-tetrame-thyl-1，5-dichloro-3，3-diphenyltrisiloxane (B) Were obtained by the reactions of methylt-richlorosilane and dimethyldichlorosilane with diphenyldichlorosilane，respectively．The wholly methylsilanol-terminated silicone resin (I) was prepared from (A) and (B) in proper pzoportion．Also．two another kinds of methylsilanol-terminated silicone resins (II) and (III) were produced by the reactions of methyltrichIorosilane and methyltria-cetoxyisilane,respectively,with the phenylsilanolterminated silicone resins prepared by the hsual cohydrolysis method．The methylsilanol-terminated silicoffe resins(I，II，III) can be cured more than two times faster than the phenylsilanol-terminated silicone resins prepared by the usual cohydrolysis method．
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发布时间：2021-03-19 - 摘要：The curing characteristics of butyl glyeidyl-4, 5-epoxycyclohexane-1, 2-dicarboxylate with m-PDA have been studied by TBA, DSC, and IR. It is found that the curing process of the curing system proceeds in two stages, and the apparent activation energy is 13.9 kcal/mol in the temperature range from 100 to 160℃ and 16.6 mcal/mol from 160 to 240℃. Owing to the lower reactivity of the cycloaliphatic epoxy ring in the molecule, the sample storage life for about eighty days is predicted based on the extrapolation of the experimental data.
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发布时间：2021-03-19 - 摘要：A methed of Comparative DSC technique is proposed for physical aging study. The essential of the comparative DSC technique consists of comparing the enthalpy relaxation behavior of aged sample with quenched sample as a reference. The accuracy of comparison is improved because of simultaneous measure of the sample and reference which makes noise of the apparatus subtractive. The technique has been applied to study the influence of crosslinking on the enthalpy relaxation behavior of epoxy resins. Effect of cross-linking on the kinetics of enthalpy relaxation of epoxy resins are obta-ined and discussed.
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发布时间：2021-03-19 - 摘要：By means of living anionic polymerization, a series of poly(styrene-ε-caprolactone) block copolymers were synthesized. The block copolymer is confirmed by GPC, column fractionation and infra-red spectra. The ring-opening polymerizations of ε-caprplactone by using living polystyrene, the properties of corresponding block copolymers and their structures were studied. The block copolymers exhibit microphase separation, and present multiphases which consist of amorphous polystyrene segments, amorphous poly-e-caprolactone segments and crystalline poly-ε-caprolactone segments.
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发布时间：2021-03-19 - 摘要：Without chain crosslinking and degradation, polybutadiene (PB) was chlorinated with t-BuOCl to give chlorinated polybutadiene (Cl-PB) with labile halogen atoms on the backbone. Comb-shaped PB was prepared by coupling of Cl-PB with living PB in a mixed solvent of cyclohexane and tetrahydrofuran. Characterization by GPC and os-mometry showed that purified products were well-defined comb-shaped PB of low poly-dispersity, composed of a backbone chain carrying randomly distributed grafts. The ave-rage number of branches was able to be varied in a wide range to meet the needs of stru-cture-properties relationship study.
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发布时间：2021-03-19 - 摘要：Macro-porous chelate resins of polyvinylbenzylthiourea (or thiourea resin TUE) with higher adsorption capacity for Au3+ have been prepared. After swelling in 1,4-di-oxane the macro-porous crosslinked chloromethylated polystyrene beads were treated with saturated alcoholic solution of thiourea, the obtained TUR with 98.8% conversion of functional group. The adsorption capacity of TUR, for Au3+ is equal to 819 mg Δu3+/g resin (4.16 mmol Au3+/g resin.) under the best condition, the adsorption capacity reacher to 920mg Au3+/g resin. In polymeric complex the chelate mole ratio of approaches to 1. Theinfluence of pH on the percentage of adsorption for Au3+ was investigated. The adsorption rates of TUR for Au3+ were deter-mined by means of the static state method and the column method. The structure of recovering of gold from the wastewater of gold electroplating industry,with Au reco-very of ≥95.7% and 99.8% Au purity.
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发布时间：2021-03-19 - 摘要：The polymerization kinetics of 4，4'-biphenyldicarbonitrile I catalyzed by complex of 4，4’-biphenyldicarbonitfile with ZnCl2 was studied．The cyano group concentration was measured by infrared spectroscopic analysis using potassium ferricyanide as the internal reference．The results proved：the polymerization of 4，4'-biphenyldicarbonitrile is a second order reaction．The polymerization rate is directly proportional to concentrations of cyano group and complex．The rate Constants of polymerization are 0.808；1.058；1.249；1.632；1.808 1·mol-1.hr-．at 260°；270°；280°；290°；300℃ respectively．The activation energy of the polymerization is 12．4 kcal.mol-1．The polymerization rates of 4，4’-biphenyldicarbonitrile catalyzed by following eight co-mplexes of 4，4'-biphenyldicarbonitrile with chloride at 280℃ were measured The rate．constants are：I. TiCl4 1.42；I. 2ZnCl2 1.25；[FeCl3 0.785；I·2COCl2 0.706；I·SnCl4 0.418；I·AlCl3．0.396；I·2SbCl5 0.169；I·2BCl3 0.0247 1·mol-1·hr-1．The N1s binding energy shifts，measured by xvs(X-Rgy Photoelectron Spectroscopy)，are as follow：I·2ZnCl2 1.6；I·2CoCl2 1.5；I·SnCl4 1.3；I·TiCl4 1.2；[．FeCl3 1.1；I·2SbCl5 1.0；I·AlCl3 0.7；I·2BCl3 0.5 (e.v.) This fait shows tha the nitrogen atom in these complexes possesses less electron density than that in the 4，4'-biphenyldicarbonitrile molecule and then．it induces the carbon atom of the cyano group of these complexes to be more positive．This is favourable for the attack of the cyano group．by other 4，4’-biphenyldicarbonitrile molectfles therefore the rate of the polymerization is accelerated．The polymerization’mechanism may be.
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发布时间：2021-03-19
Research Article
- 摘要：S'Upermolecular Structures and crystallization behaviors of the gamma-radiation induced graft Copolymerization of styrene (St)-acrylic acid (AA) to polytetrafluoroethy-lene were investigated with electron-optical microscope and X-ray diffration.It was shown that the morphology of crystals obtained changes regularly with increasing graft dose.Four kinds of typical structure morphology (they belong to the linear structure.Graft network, ladder type network, cross-linked network) were observed from graft co-polymer layer. It is demonstrated that the grafted chain aligned perpendicular to the surface films. The results obtained from X-ray diffraction showed that the change of structure occurres; The crystallinity of macromolecular decreases;the size of crystal becomes smaller.
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发布时间：2021-03-19 - 摘要：We presented the results of propylene polymerization-kinetics on complex-catalysts obtained from reduced TiCl4, by complexation of AlEt2Cl and. isoamyl ether. The characteristics of reacting kinetic curves of polymerization were measured in the normal pressure. The rate constant, reaction order 'and activation energy were measured and rate equation, r=KGP, was developed. Experimental data of the stereoregularity of polymer was discussed in the light of the kinetic behavior of the catalyst System.
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发布时间：2021-03-19 - 摘要：Polystyrene, cross-linked with 4% of divinylbenzene, is combined with TiCl in CS2 to form a stable complex containing 20.3% of chlorine. The TiCl4 complexed in polystyrene is resistant to water and can be stored in air at least one year. The complex is a strong solid Lewis acid and can be used to catalyze a lot of organic synthesis reactions in high yield, such as esterications, acetal formations, ketogenesis, and the Friedel-Cra-fts alkylations. The complex is also a good catalyst for polymerization of α-methyl styrene.
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发布时间：2021-03-19 - 摘要：Two new expression functions for the X-ray diffraction profile of both crystalline and amorphous polyphenylene sulfide (PPS) have been proposed:andwhere X is the diffraction angle, Y the diffraction intensity at X, W1,W2 the left width and right width at half height, P the maximum position, A the peak height, and / the shape factor. 5=sinθ/λ,(λ is the wave length of X-ray). Function (1) is suitable for the profiles plotted against diffraction angle X, while function (2) is suitable for the profiles plotted against S.The limitation to the range of applicable diffraction angle,which is inherent to the old expression functions reported in literatures,has been eliminated in these two functions.
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发布时间：2021-03-19 - 摘要：The morphology of films of PDS/PP blends with various content of PDS and with PDS of different molecular weight was examined by scanning electron microscopy and the photostability of these films was studied by infrared spectrometry. Experimental results show that PDS is dispersed in PP matrix as spherical globules being in size of the order of 10-1 μ when content of PDS is in the range of 0.1% to 1%. The phase separation of PDS from PP results in decrease in photostabilizing action of PDS to some extent. It is found that films of PP biended with PDS of different molecular weight show similar morphology and photostabilizing action if the content of PDS is kept the same.
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发布时间：2021-03-19 - 摘要：A poly (vinyl chloride diethyl maleate) copolymer has been fractionated by repeated precipitation method. All fractions and the unfractionated sample have been characterized by viscometry, dynamic osmometry, Zimm static osmometry, light scattering and gel permeation chromatography. After correction for polydispersity, a monodis-persed [η] -M relationship has been obtaind:[η] = 1.99 × 10-3M0.87 (ml/g,at 25℃, in cyclohexanone)For the copolymer solution in THF, the second virial coefficient a decreases as the molecular weight increases. The relationship is.
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发布时间：2021-03-19 - 摘要：Aliphatic tertiary amino-group N'-substituted acrylamides, N-acryl-N'-methylpipe-razine(AMP),N-methacryl-N'-methylpiperazine(MAMP) display better antithromboge necity by the recalcification testing method. Even though AMP and MAMP hardly proceed the polymerization initiated with BPO, but at lower concentration would form redox system with BPO to initiate the polymerization of MMA readily. The rate equation of the polymerization of MMA initiated by MAMP-BPO system was given as Rp= K,(MMA) (MAMP)I/2(BPO)1/2 and the overall activation energy was determined as low as 10.2Kcal/mol. The analysis of the obtained polymers confirmed that MAMP not only initiated the polymerization of MMA by combining with BPO,but also took part in the polymer chains with better antithrombogenecity.
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发布时间：2021-03-19 - 摘要：The yield of copolymerization of tetrahydrofuran(THF) and epichlorohydrin(ECH, 10%, by wt.) using a binary catalyst of fuming sulfuric acid(21% or 28%) and perchloric acid or sodium perchlorate is higher than 60%. The average molecular weight of the product can be controlled in the range of 1000-2000 by varying the catalyst system. The hydroxyl functionality of the product is equal to 2, and the end-groups are predominantly primary hydroxyls(around 70-80%).
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发布时间：2021-03-19
Research Bulletin
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