最新刊期
卷 ， 期 3 ， 1982
- 摘要：9-vinyladenine was synthesized by a 'simple method, and a new polymer was prepared by copolymerization of 9-vinyladenine with maleimide. By comparing the IR, NMR and UV spectra of this polymer, with those of polyvinyladenine and polymalei-mide, it clearly shows that it is a copolymer having hydrogen bonds between molecular chains. This copolymer has the same UV absorption as nucleic acid.
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发布时间：2021-03-19 - 摘要：When poly (ethylene terephthalate) fibers were irradiated by gamma radiation in air, macromolecular peroxides were formed, which could be decomposed into macromole-cular radicals by hydrazine cupric ion catalytic system. These radicals thus formed can initiate in situ graft copolymerization of acrylic acid in its aqueous solution. The oxygen in the reaction medium has no effect on the graft yield. There is a optimal concentration range of the hydazine for the graft reaction pertinent to the graft condition. The graft yield increases with cupric ion concentration within the range of 0---2.5×10-3mole/l.
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发布时间：2021-03-19 - 摘要：The influences of isotacticity on the mechanical properties in four different sizes and piled up of spherulites of polypropylene "were studied under uniaxial stretching. The mechanism of stretching deformation for different spherulite were examined by polarizing microscope.In general, one can find some influences of isotacticity on the mechanical properties of polypropylene, but the influences of size and piled up of spherulltes are even more important. The differences in the mechanical properties of polyproylene with different spherulites are closely related with theri differences in the stretching deformation me-chanism.
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发布时间：2021-03-19 - 摘要：Cis 1,4-polybutadiene synthesized by rare-earth catalyst has high cis content, high degree of molecular reqularity and low degree of branching. The crystallization and morphology of the polymer were studied at low temperature with electron microscope-It was observed that the morphology and growth rate of spherulites are affected by the degree of molecular regularith and conditions of crystallization.
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发布时间：2021-03-19 - 摘要：The heat ageing interaction of silicone rubber with three of fumed silica having different surface property was studied. The rubber compounds and vulcanizates were swelled in toluene and in toluene over ammonia; bound rubber as well as swelling degree of the vulcanizate were determined. It was found that a significant amount of chemical crosslink is formed between filler and rubber chain upon heat treatment, meanwhile the interfacial hydrogen bond is transformed to chemical linkage. The formation of chemical linkage as well as hydrogen bondis greatly reduced by surface modification of the filler before or during compounding.
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发布时间：2021-03-19 - 摘要：This paper introduces the discrimination criteria for the screening of rival models. From among five rival models, an expression describing the X-ray scattering by amorphous component of PET fibers has been established. The computational multi-peak resolution method for X-ray diffraction pattern of PET fibers has been programmed.The multipeaks in several kinds of PET fibers have been resolved and, their structural parameters have been investigated with satisfactory results.
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发布时间：2021-03-19 - 摘要：The polybutadiene (cis-1, 4 and 1, 2) polymerized with iron catalyst was investigated by 18C-NMR. Assignments have been made on the spectra for all peaks of the Aliphatic and olefinic carbons using chemical shift corrective terms together with furukawa parameters. The relative intensities of peaks were calculated from the ber-noulli distribution of cis-1, 4 and 1, 2 units.Quantification of cis-1, 4 and 1, 2 contents, sequence distribution, alternation pattern of cis-1, 4 and 1, 2 units, and the chain propagation mechanism were discussed as a result of the detailed stdy of the spectra.
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发布时间：2021-03-19 - 摘要：Monomer sequence distribution of copolymers of butadiene and isoprene prepared with lanthanide complexes LaCl2-C2H5OH-Al(C2H5)2 was determined by 13C-NMR spec-trometry.The dyad distribution and number-average sequence length of these copolymers were quantitatively determined. The results show that sequence distribution of monomer units in copolymers prepared with Nd, Pr and Ce catalysts follow Bernoullian statistical model, while copolymers prepared with Y, Sm, Dy and Gd catalysts show some deviation from it.
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发布时间：2021-03-19 - 摘要：Poly-N-(vinylbenzyl)ethylenediamine is a functional polymer of scientific and economic significance．Owing to the disubstitution of ethylenediamine(EDA)during the direct amination of crosslinked chloromethylated polystyrene with EDA，predo-minant secondary crosslinlrlng usually oceurs，resulting with a low content of the ex-pected primary amino group．The disubstitution has been diminished to 13．3％by some improvements done in this laboratory，and SO the content of the primary amine has been raised to as high as 43.3％．In another method．to avoid the EDA disubstitution one of the two primary amino groups in EDA was acetylated prior to the amination procedure，and the primary amino group was regenerated through a hydrolysis procedure．The two investigated methods resulted mainly in the desired monosubstituted products．The products obtained from these two different methods were applied to the separa-tion and purification of streptomycin，of sh owed the desirable properties．
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发布时间：2021-03-19 - 摘要：In order to get the title compound the functionalization of ehloromethylated PS were carried out in the following two ways：(1)The poly-N-(vinylbenzyl)amine resin prepared was reacted with N-(β-bromoethyl) phthalimied，followed by the bydrazinolysis．It has been verified that the two reactions proceed as anticipated．(2) Chloromethylated PS was aminated with ethanolamine，after which the hy- droxyl group of the amine was replaced by a halogen and then followed by reacting with hexamethylenetetramine．Each reaction involved，was studied，and the anomalous phenomena exhibited in the final stage were dmcussed．To avoid the probable side reactions，the secondary amine of the intermediate was successfully blocked．However the side-reaction persisted because of the cleavage of the amine bond during the haloge-nation with phosphorus trihalide．
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发布时间：2021-03-19 - 摘要：The a-amino acid functionalized asymmetric resins were prepared by the reaction of the aniliniuin resins with a-amino acids，or by the amination of chloromethylated styrene-divinylbenzene copolymers with a-amino acids in the presence of phase-transfer catalysts for chromatographic separation of racemic compound．The structures of the asrmmetric resins were confimed by infrared spectroscopic analysis．The factors affecting the properties of the asymmetric resins，such as the pro-perties of solvents，amount of catalysts，the temperature and time of the reaction etc.，were．investigated．The L-proline functionalized asymmetric resin was prepared by the two aforesaid procedures．The copper (II) complex of the L-proline functionalized asymmetric resin was utilized for ligand-exchange chromatography of the resolution of DL-proline，thus，we resolved the racemic mixture into the D-and L-proline．
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发布时间：2021-03-19 - 摘要：The long chain branching in polybutadienes and their hydrogenated samples were studied by 13C-NME spectrometry.Two kinds of branching structures are suggested. For samples polymerized from Ni and Co catalysts systems the branching point is on the a-methylene group of the Cis-1,4 double bond. For samples polymerized from Ni+Mo catalysts systems, branching point is formed through the opening of the double bond of 1,2 vinyl group.
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发布时间：2021-03-19
Research Article
- 摘要：In the synthesis of butyl rubber using transition metal halide and alkylaluminum halide catalyst in alkane solvents, the molecular weight distribution (MWD) of the copolymers can be controlled by adding certain amount (30-40%) of solvents of higher polarity, such as alkyl halides, into the alkane. The butyl rubbers thus obtained have approximately the same MWD, processing behavior and physical and mechanical properties as those of polysar 301.
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发布时间：2021-03-19 - 摘要：The structure of poly-r-mercaptopropylsiloxane-Pt complex catalyst was studied by X-ray photoelectron spectroscopy (XPS).Our results show that the complex is formed by coordination of the lone-pair electron of the sulfur atoms on two poly-r-mercaptopropylsiloxane molecules to one platinum atom in H2PtCl6. The catalytic activity is lost with destruction of the complex and PtIV is reduced to Pt11 simultaneously. This fact is in accordance with the deactivition of H2PtCl6.
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发布时间：2021-03-19 - 摘要：2,3-dimethylbutadiene-l,3 was polymerized in heptane with tercomponent catalyst Nd(naph),-Al(i-Bu),-AlEt,Cl at 50℃. It is evidenced by IR, X-ray and .13C-NME that poly-2,3-dimethylbutadiene thus obtained is constituted mainly of Cis-1,4 units.
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发布时间：2021-03-19
Research Bulletin
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