最新刊期
卷 ， 期 6 ， 1982
- 摘要：Styrene-co-maleie anhydride，vinyl acetate-co-maleic anhydride，methyl methacry-late-co-maleic anhydride eopolymers were deposited Oil the surface of carbon fibers by an electrodeposition technique．The anion-free radical mechanism of this process and the physical adhesion te the surface were P reliminarily confirmed．The adhesion at fiber-resin matrix interface in earban fiber reinforeed plastics was improved by the electrodeposited polymer interlayer and the shear failure occurred mainly in the matrix．Interlaminar shear strength of the unidirectional carbon fiber reinforced epoxy com-posite is increased from about 600 kg／cm2 to 1,000 kg／cm2 by electrodeposition of poly-mers and the strength loss of the composite which has been immersed in boiling water for 100 hrs．is decreased．
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发布时间：2021-03-19 - 摘要：Pole figures of crystal planes (020) and (110) for uniaxially stretched polyvinyli-dene fluoride were measured by X-ray diffraction. Samples were drawn at 100℃ and 160℃, with extension ratio from 250% to 420%.Numerical values of the mean-square cosines of the crystal planes are calculated from fully corrected intensity distribution.The mean-square cosines with respect to drawing direction were obtained by coordinate transformation with the use of Wilchinsky method.When T = 100℃, during the drawing process the crystal was transformed from a-form to β-form,and the diffraction intensity and position of diffraction peak changed.
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发布时间：2021-03-19 - 摘要：Condensation polymer of salicylic acid, formaldehyde and methyl amine (SFMA) was prepared by Mannich's condensation. The Catalytic kinetics of hydrolysis of p-nitrophenyl acetate (PNPA) by SFMA was investigated. The results indicated that SFMA shows greater rate enhancement than salicylic acid and its polycondensate with formaldehyde for hydrolysis of PNPA in aqueous solution. Effects of pH values of solution, polycondensate's component and conformation in solution on the catalytic activity of SFMA were also studied.
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发布时间：2021-03-19 - 摘要：As a model of Serine hydrolase, the p olycondensates of salicylic acid, formaldehyde and methyl, n-propyl, n-hexyl, or n-lauryl amine were prepared by Mannich's condensation. The catalytic activities of the above polymers for hydrolysis, of p-nitrophenyl acetate (PNPA), were investigated. It was found kinetically that the rate of hydrolysis of PNPA increases with increasing length of the alkyl groups in the side-chain of the polymers. Hydrolysis of PNPA catalyzed by the polycondensate of salicylic acid, formaldehyde and n-laurylamine proceeded by the simple Michaelis-Menten type mechanism. The kinetics parameters were obtained as: Km=6.7×10-5M,and Vmax=2.07×10-7M·min-1.
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发布时间：2021-03-19 - 摘要：The UV-photolysis of vinylidene chloride/methyl acrylate copolymer (VDC-Co-MA) has been studied by using X-ray photoelectron spectroscopy(ESCA) under atmosphere and inert environment. Several possible photochemical reactions, such as cleavage of C-C1 bond and photo-oxidationetc, have been discussed from the variation of ESCA informations with different irradiative time.
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发布时间：2021-03-19 - 摘要：The effects of a series of eompooinds having varied structure and polarity on the polymerization of butadiene with the rare-earth catalytic system were studied. It was found that for most of these compounds the catalytic activity is lowered and the molecular weight of the polymers is increased, with the exception of allyl derivatives both the catalytic activity and the molecular weight are lowered. In view of its relative long lifetime and the insensitiveness towards modifiers usually used in Ziegler-Natta cataly-tic systems,the rare-earth catalytic system is assumed to have its special nature,lead-ing to somewhat different polymerization mechanism.
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发布时间：2021-03-19 - 摘要：The morphology of segmented copolyether-esters with low hard segment content has been studied by TEM. It has been found that the size and shape of these domain structures are determined by two competitive factors: the rate of phase separation of the components and the rate of crystal growth. The fine struture in domain is related to the nucleating rate, and crystal growth rate. In case of samples with PET as hard segment the ratios of Va/Vc and Va/Vn are larger than those of samples with PBT as hard segment.
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发布时间：2021-03-19 - 摘要：The title resins (DTC resins) with high adsorption capacity were prepared. The influences of various reaction conditions of amination and dithiocarboxylatiom were examined. The adsorption capacities of the produced DTC resin for Hg2+, Cu2+, Zn2+, Cd2+ are 4.40, 2.44, 1.77, 1.36 mmol ion/g respectively. It is highly effective in collecting traces of heavy metal ions in water over a wide pH range. The conversion of functional groups were confirmed by IR-spectra and elemental analysis.
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发布时间：2021-03-19
Research Article
- 摘要：The adverse effect of PVA on the rate of polymerization of AM was studied. The decrease in the rate of polymerization of AM and the amount of PVA was quantitated. At 40℃ the ratio of concentration of hydroxyl group to the concentration of "dead" AM is just 2 to 1. The effect of PVA on the polymerization of AM was reduced as the temperature of polymerization was increased.A analogous effect for 1,3-propylenediol on the rate of polymerization of AM was also observed. The mechanism of above effect was discussed.
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发布时间：2021-03-19 - 摘要：The homopolymerization of MTMP and the copodymerization of this monomer with styrene were investigated. Homopolymerizations of styrene and methyl meth-acrylate were performed separately in the presence of model compound, 4-hydroxy-2,2,6,6-tetramethyl piperidine, under identical conditions. In the above polymerization with AIBN as initiator, the inhibition effect of compounds bearing piperidinyl imino group, is not obvious. The influence of solvents on the copolymerization of MTMP with styrene was discussed.
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发布时间：2021-03-19 - 摘要：The quenching of singlet state styrene by triethyl amine (TEA) and polymer amine (P-TEA) has been studied. The results show that there is a linear relationship between relative fluorescence intensity I0/I and concentration of amine over a wide range, and it can therefore be used to determine the amounts of the terminal amine group in polymer.
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发布时间：2021-03-19 - 摘要：The chemiluminescence from the high density polyethylene was studied. The effects of thermal history in processing, Addition of antioxidant, thermooxidation and photooxidation on chemiluminescence were discussed.
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发布时间：2021-03-19 - 摘要：The interface bonding of graphite fiber/epcxy resin has been investigated. The acidic groups on the graphite fiber surface were determined by flow microcalorime-try after oxidation treatment with nitric acid. There is a good correlation beween the concentration of the acidic groups and the interlaminar shear strength of the composites, which decreases as the acidic groups are reduced by heating in a hydrogen stream.Prom these experimental results, it was justified that the chemical reaction oc-cured between the epoxy resin and the acidic groups of the surface of the graphite fiber is responsible for the interface bonding.
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发布时间：2021-03-19 - 摘要：The change in the intensity of infrared absorption bands of Nylon 1010 with its density has been observed for film samples annealled at dfferent temperatures after quenching from the melt.It has been found that the absorbance of 1007 cm-1 band increases linearly with the density. The density of amorphous Nylon 1010 is obtained by extrapolation to zero absorbance. The intensity of 940 cm-1 band does not vary linearly with the density, as reported for other polyamides in the literatures.
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发布时间：2021-03-19 - 摘要：The plasma homo polymerization of ethylene and propylene was carried out in a capacitive coupling external electrode apparatus.The structure of the polymers was found to be highly cross linked through characterization by using elementary analysis, IR and X-ray diffraction methods.
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发布时间：2021-03-19 - 摘要：The process of hydrolysis of both aspirin and the title copolymer was studied by fluorescence spectra. Our results showed that a large variation of rate of hydrolysis may occur when aspirin is immobilized to a polymer support.By comparing the fluorescence spectra and hydrolysis rate of both aspirin and methyl salicylate, it can be concluded that in a sequence of reactions from copolymer to salicylic acid, the acetyl group of the copolymer is first cleaved, and then followed by the cleavage ester link with the formation of salicylic acid.
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发布时间：2021-03-19
Research Bulletin
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