最新刊期
卷 ， 期 2 ， 1982
- 摘要：Grafting polymerization of aerylamide (AAM) onto polyether urethane (PEU) was investigated in aqueous solution by using eerie ammonium nitrate (CAN) aa initiator．The grafted polymers were synthesized as follows：(i) a variety of PEU from poly (oxytetramethylene) glycol (PTMG)，4，4'-diphenylmethane diisoeyanate (MDI)，and ethyleneamine (E) or butandiol (B) as extender under different reaction conditions were used to east into films；(ii) grafting of PAAM onto PEU film by using CAN and (iii) the grafted PEU substrate was then extracted with boiling distill-ed water．to remove the residues of AAM and PAAM homopolymer．The PEU films of varying thicknesses with either B or E as extender could be easily grafted by A A M．The grafting polymerization was verified from the fact that the grafted substrates be-come opaque and possessing higher percentage of water absorption than the original one，and from the scanning electron microscopy photographs with saHent mierograph showing grafts of maeroehain on the surface of fiIm．In addition，the faetors that in-fluenee the grafting eopolymerization were studied，and the mechanism of grafting polymerization has been proposed．
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发布时间：2021-03-19 - 摘要：The molecular weight distribution functions of the reaction system of Aa1+Aa2+…+Aai (an A group can react with an A group) and of the reaction system of Aa1+Aa2+…+Aa+Bb1+Bb2+…+Bbj，(an AA group can react with a B group)have been derived by using the theory of stochastic cascade process and by using Good’s results of multidimensional Lagrange expansion．These distribution func-tions are identical with those obtained from classical combinational theory which was established by Stockmayer．Ftom the results thus established，two distribution fune-tions may be applied to the range beyond the gel point．
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发布时间：2021-03-19 - 摘要：The polymerization mechanism of various vinyl monomers in the presence of arematie tertiary amines has been studied．It was found that the mechanisms of differ-ent monomers are varied with the structure of monomer．Those monomers，such as Methacrylie esters．containing a一CH3 on the vinyl carbon atom could be polymerized with aromatic tertiary amine in the absence of light．while the monomers without a一CH3 group，such as methyl acrylate，aerylonitrile etc．would polymerize only under light．The mechanism of former case has been proposed that the a一CH3 gronp will be first oxidized by amine-O2 complex to the e orresponding hydroperoxide which then reacts with amine as redox system to produce the free radical species for initiation．Since in the later ease there is no such group to be oxidized，thus the mechanism has been proposed that the excited charge transfer complex (exeiplex) between mono-mer and amine will be formed under irradiation and then decompose to produce free radical species for initiation．The structural effect，both of the monomer and of the amine，on the rate of pho-topolymerization were studied．The activities of monomers and amines may be arranged in the following descending order as： It is revealed that both the electro．negative group on the double bond of monomer which acts as an accepter and the electro-positive group on the nitrogen atom of amine which aets as a donor would effectively in crease the rate of photopolymerization．
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发布时间：2021-03-19 - 摘要：The morphological structure of PE obviously affects irradiated crosslinking. The more irregular in the arrangement of the structure of crystalline morphology is, the lower in crystallity and more interface will be, resulting in the formation of more crosslinkis between molecules.Through observation of spherulite deformation by drawing, etching and melting, We may perceive that crosslinking can occur at all interfaces, preferentially between lamellas.When the amount of gel reaches 92%, with the incresing of the does of irradia-tion the crystallinety decreases and the size of crystal becomes smaller. At the same time,the refractive index and density increase while the segmental orientation of macromolecule decreases.
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发布时间：2021-03-19 - 摘要：This paper deals with interatomic distance function of rareearth cis-1, 4-polybuta-diene by RDF derived from electron diffraction. The RDF obtained from the analysis of the experimental intensity curves of electron diffraction can be used to characterize the short-range order of amorphous systems. Two intramolecular peaks and three in-termolecular peaks have been found RDF. The appearance of such a number of intermolecular maxima on the RDF can be explained by the local parallel packing of long chains molecules of the amorphous polymers.
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发布时间：2021-03-19 - 摘要：From the transmission electron microscopic study, it has been found that in the graft copolymeri/ation, the morphology of graft latex particle, its quantity as well as particle size distribution of free SAN are closely related to the initation systems, the proportion of first monomers feeded, and the way of adding monomers.
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发布时间：2021-03-19 - 摘要：A new poly (N-e-methacrylamidocaproyloxy-5-norbornene-2, 3-dicarboximide) was obtained by radical polymerization of corresponding monomer, in turn prepared by coupling of e-methacrylamidocaproic acid with N-hydroxy-5-norbornene-2, 3-dicarboximide in the presence of dicycl ohexylcarbodiimide. The new polymer proved to be good carrier for the immobilization of trypsin. This immobilized trypsin had rather high enzymatic activity.
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发布时间：2021-03-19 - 摘要：The copolymerization of MTMP(2，2，6，6-tetramethyl-4-piperidinylmethacrylate，M1) with St(styrene，M2)，MVK(Methylvinylketone，M2)，AN(acrylonitrile，2)and VAe (vinyl acetate，M2) was conducted in benzene at 60±0.1℃ by using ABVN (or AIBN) as initiator．The composition curves of the eopolymers and the monomer reac-tivity ratios of four pairs of monomers have been determined(MTMP．St：γ1=0.30士0.05，γ2=0.63±0.05；MTMP-MVK；γ1=0.53土0.05，γ2＝0.41±0.05；MTMP．VAc：γ1=14土0.5，γ2=0.02±0.01；MTMP—AN：γ1=13.7±0.5，γ2=0.20士0.05)．The Q(0.56) and e(0.49)values of MTMP have been calculated and the microstructure of the copolymer has been described．
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发布时间：2021-03-19 - 摘要：A computer program which is used to correct the peak spreading of GPC chroma-togram has been proposed for calculation the various average molecular weight and MWD of polymer.In this program, the method to smooth the curve is especially suitable for narrow peak.The effect of the product (h.△V) of resolution factor h and computational interval △V on the relation between precision Rf and iterative number L is also discussed.
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发布时间：2021-03-19 - 摘要：Vinylidene bromide (VDBr，M1) was copolymerized with different comonomers (M2)，including methyl acrylate (MA)，methyl methacrylate (MMA) and styrene (St)．The influences of properties and sequence distributions of the resulting eopolymers on the UV sensitivity of the recording materials have been investigated．It has been shown that UV sensitivity is the highest for eopolymer cotaining St and lowest for that con-taining MA．For recording materials prepared from same eopolymer，their UV sensi-tivity are related to the sequence distribution of the copolymer，especially P2(M1M2)．The reactivity ratios (r) of different monomers in the free radical copolymerization of VDBr with MA，MMA and St at 55土0.2℃，by using AIBN as initiator，were deter-mined, i.e. for VDBr-MA，r=0.72土0.05，r2=0.72士0.05；VDBr-MMA，r1=0.50±0.04．r2=1.74土0.04；VDBr．St，r1=0.4±0.04，r2=1.12士0.04．
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发布时间：2021-03-19 - 摘要：The separation ability and zone broadening effect in mobile phase have been studied by using GPC columns packed with nonporous glass beads．Polymer samples of different molecular weight could be separated to some extent on these colunlns．Kelley and Billmeyer indicated that the theoretical plate height describing zone broadening effect in mobile phase depends on the’molecular weight of solute only．However．the width of peak was found to be different in samples of the same molecular weight but of different molecular weight distribution in the present inves-tigation．The reverse flow zone broadening factor，h，of benzene is somewhat larger than the straight through flow zone broadening factor，h’．This may bd explaned by the fact that the velocity profile of flow was disturbed during reverse flowing．In GPC columns packed with porous silica beads the dependence of reverse flow zone broadening factor，h，on elution volume，Ve，has been examined for a series of samples of different chemical structure，different molecular weight and different mole-eular weight distribution． Experimental results showed that the relation between h and Ve is universal，independent of chemic al structure of polymer samples in agreement with Tung’s．h>h’was also found for benzene in columns with porous packing．This indicates that the use of h value obtained from the reverse flow method mny lead to slight underestimation of the zone broadening effect in GPC．The shape of reverse flow elution curve was found to be very close to Ganssian only for polymer samples with narrow molecular weight distrihIution within the pre-meation limit of the column used．
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发布时间：2021-03-19
Research Article
- 摘要：This paper describes a new series of polyphenylquinozaline (PPQ). The starting material, para-bis(p-chlorophenylg!yoxaloyl)benzene(CPGB) was prepared via Grignard reaction. Chlorinated polyphenylquinoxaline was then obtained through cyclocondensa-tion reaction of 3, 3'-diaminotenzidine(DAB) and 3,3', 4,4'-tetramino-diphenyl ether (TAPE) with CPGB. They have higher T, than that of PPQ itself. Block and random copolymers of PPQ were prepared by the reaction of DAB and TAPE with 1,4-bis(phenylgloxaloyl) benzene (PGB) in m-cresol at room temperature. These poly-mers and copolymers exhibit higher thermoxidative stability, and excellent high-temperature resistance even in the presenceof water.
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发布时间：2021-03-19 - 摘要：A method for determining the content of cyclosiloxanes in silicone emulsion by gas choromatography was established. The rates of diffusion and polymerization of hexa-methylcyclotrisiloxane (D3), octamethylcyclotetra-siloxane (D4) and decamethylcyclopen-tasiloxane (D5) in the presence of dodecyldimethylbenzylammonium bromide were investigated. As the amount of polymer produced increases, D4 increases accordingly in the water layer. It can be assumed that the OH-ended polydimethylsiloxane may serve as a sort of co-emulsifier.
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发布时间：2021-03-19 - 摘要：l-(Acetylsalicylyl) benzotriazole, a new active amide of acetylsalicylic acid has been synthesized either from acetylsalicylic acid and benzotriazole using DCCI as condensation agent or via acetylsalicylyl chloride and benzotriazole in the presence of triethyla-mine. The obtained active amide reacted readily with the hydroxyl group of PVA to produce the acetylsalicylyl ester of PVA.
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发布时间：2021-03-19
Research Bulletin
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