最新刊期
卷 ， 期 6 ， 1995
- 摘要：ufonic acid-group, phosphoric add-group and amino-group were introduced onto ethylene-vinyl alcohol(EVA) backbone respectively and the corresponding polyionic complexes (PICs) were obtaind. Viscoelastic spectra show that the crystallization and the hydrophobic interactions of the ethylene units and the backbone of EVA main chains have some contribution in maintaining the mechanical strength, especially the formed PIC. In the H2O- DMF-inorganic electrolyte shielding solvent systems, these PICs were more soluble using Ca(SCN)2,ZnCl2 or NaSCN than using NaBr or LiBr.
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发布时间：2021-03-19 - 摘要：Thermal decomposihon processes in poly(β-hydroxybutyrate)(PHB) and Poly (β-hydroxybutyrate-co-β-hydroxyvalerates) [P(HB-co-HV)s] with composihon ratios HB/HV of 96:4 and 82:18 were investigated by direct pyrolysis mass spectrometry (DPMS). It can provide up to hoptelner pyrolynates and estimate the composition and sequence distribution of copolymers. The results indicate that the thermal degradation of PHB and P(HB-co-HV) occurs quite selctively through a β-Hydrogen transfer process, with formation of oligomers bearinng carboxyl and olefin end-groups. Oligomeri groducts corresponding to dehydrated monomer up to heptamer were also identified both in the case of PHB and P(HB-co-HV).
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发布时间：2021-03-19 - 摘要：he main kinetic parameters such as the concentration of active propagating chain ([C*]), the efficiency of catalyst (ELCU) and the rate constant of absolute propagahon (kp) as well as the average lifetime of growing chain (τ). have been determined at 30 ℃, 40 ℃ and 50 ℃. The propagation activation energy of isoprene polymerization has been found to be 57.4 kJ/mol in heptane. The experimental results showed that the catalytic activity for the polymerization of isoprene is dominated by the rate constant of absolute propagation in this system.
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发布时间：2021-03-19 - 摘要：Using FTIR, the relations between the concentration of the gauche conformations and its distribution in the UHMPE gel-films prepared from different conditions and their superdrawabilities have been studied. It has been found that the gauche conformations and the chain entanglements are closely related and the conformation ratios (σ=I1303/I1352) increases with the concentration at which the gel-films were prepared. There exist critical concentrations (0.4- 0.5g/100ml) corresponding to the proper chain entanglements as obtained from ηsp on which maximum draw ratio can be reached (λmax).Annealing also has great influence on σ, but temperature is more important than time. Superdrawability could be attained in the annealing temperature range when σ has the lowest value.
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发布时间：2021-03-19 - 摘要：he mechanism of annealing crystallization for crystalline polymers PET (polyethylene terephthalate) and PEET (Polyethylene-1, 2-diphenoxyethane-p, p'-dicarboxylate) blends was stlldied. The observation and study by DSC, X-ray and polarization microscope show that chemical reaction of ester interchange-copolymerization did not occur in the melt "dxing for PET and PEET. Every component crystallizes independently. Their crystallinity, crystallization rate and spherulitic texture are influenced by two factors, that is, crystallization temperature and blend composition. The data of hindered crystallization factors that express the influence of crystallization temperature and blend composition was proposed.
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发布时间：2021-03-19 - 摘要：The compatibility,miscibility, membrane-formability, structure and LC transition properties of PEECB-4.05(α,ω-polyethylene glycol(DP=4.05)-p-ethoxycarbonyloxybenzoate)/hydrocarbon rubber(SBR,PB)/PDMS(Mw=370×103) composite membrane PDLCM have been charactenAn by IRS DSC, WAXD, cross-polarized microscope and SEM, TEM etc. Results showed that PEECB-4.05'sTk-s(transition temperature from crystal state to LC state) has been downed 37.5 ℃ to ambient temperature in SBR/PEECB-4.05/PDMS system because of the interactions between the components. There exists imperfect micro-phase separation in the system and LC-rich domains have been formed (domain size from 0.2 to 2.2 micron depending on the content of peecb-4.05).These despersed domains gradually changed to continuous phase with the increase of PEECB-4.05's content, resulting in the formation of large number of LC channels upon the action of gas pressure permeated. The mechanism of PEECB-4.05 Tk-s's downing has been investigated.
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发布时间：2021-03-19 - 摘要：onic conductivity of epoxy resin -polyethylene glycol (PEO400) interpenetrating polymer netword(IPN) containing sodium perchlorate salt betWeen 15-70 ℃ under pressure from 0 to 40 MPa were investigated. The conductivity maximum exists near 6 MPa on conductivity versus pressure curve for there amorphous films. Over 6 MPa pressure the conductivities decreased further with increasing pressure. The effect of pressure on the achvation volume is determined. These were compared with those of IPN containing lithium perchlorate. For pressure dependence of conductivity and activation volume, a microscopic explanation was obtained by considering the iondipole interaction and the re-sults indicated the ion micropassage in polymer ion conductor was effected by mobile ion size. The less ion radius is, the more effective on passages is and the greaster conductivity changes are.
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发布时间：2021-03-19 - 摘要：A series of segment polyurethane-ureas from different kind of aromahc diamine chain extenders were prepared by laboratory-scale RIM machine. IR, DSC, DMTA, SEM have been used in comparing with tensile testing results to study the stmcture and properties of PUU. The influences of hard segments consisting of disocyanate and one of the three extenders (MDA, DETDA and CAMDA) on structure and properties of RIM PUU elastomers showed that the interface force index of soft-hard segment domain for the MDA-based material was smaller and its degree of phase separation was greater than that based on either DETDA or CAMDA,while the DETDA-based one had ideal inter-face force index and adequate degree of phase separation resulting in its best properties among the three. Moreover,the RIM material based on DETDA had less dependence of modulus on temperature compared with materials based on either MDA or CAMDA.
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发布时间：2021-03-19 - 摘要：conductive composite film of polyaniline (PAn) and polyvinyl alcohol (PVA) was prepared by in-situ polymerization of aniline on to PVA film. The composite film has high conductivity and good mechanical properties. Its conductivity can reach 5.8s/cm, its tensile strength 13 MPa and ultimate elongation 110%. The conditions of preparation, stability, mechanical properties and conductivity of the composites film were discussed. The composites film were characterics by CV curve. SEM and FTIR.
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发布时间：2021-03-19 - 摘要：n the comparative research, the effect of curing agents on hydrophobicity of hydroxyl terminated polydimethylsiloxane coatings with C6H5-NH-CH2-Si(OC2H5)3, NH2-(CH2)3-Si(OC2H5)3 and Si(OC2H5)4 has been studid respectively. It has been found that the surface hydrophobicity of polydimethylsiloxane coating cured by NH2(CH2)3Si(OC2H5)3 diminishes considerably. By means of ESCA and phase-contrast microscope, it has been demonstrated that the curing of NH2(CH2)3Si(OC2H5)3 itself is the reason of this phenomenon.
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发布时间：2021-03-19 - 摘要：he aromatic-aliphahc copolyamide based on terephthalyl chloride (TPC), p-phenylenediamine (PPD) and 1, 6-hexanediandne (HDA) was synthesis by low temperature solution copolycondensahon in abide-salt solvent system. The effeCts of the add accepters (AA) and each components of the amide-salt solvent system on the sequence structure, random degree (B) and number average sequence length (Ln), were studied. In order to obtain the aromatic-aliphahc copolyandde with higher B and less Ln, the pKa of AA usually has to be similar to the pKa of diamines used as monomers and the ε and DN of solevents used should be higher and the amount of the salt used must be reasonable in polycondensation system.
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发布时间：2021-03-19 - 摘要：The ethyl cellulose (EC)/Nylon-1010 blends of various proponions (5-25wt%) were prepared by using small single screw extruder, and the blends were studied in terms of WAXD, DSC, rheological experiment, mechanical mechanical etc.. The results showed that the morphology and structure of the Nylon-1010 were changed in the blends while the strength and modulus of the EC/Nylon-1010 blends were somewhat increase. In usual injection rate region, the viscosity was significantly decreased. Espedally, when the content of the EC in the blends is 15% and 20%,the improvement of these properties is more dis-tinct.
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发布时间：2021-03-19 - 摘要：he photosensitive polymerization in the types of complex systems comports of water-soluble (PAA-AM) and surfactants (CTAB, SDS, Triton X-100) was studied in this paper. The aggregation process and microenvironmental propelles of these complex systems were monitored by fluorescence probe pyrene. Compared with micelle, the molecular aggregation complex systems showed stronger aggregation ability, better stability, greater local viscosity and polarity, therefore a powerful catalytic effidency on photopolymerization of MMA initiated by benzophenone/triethyl amine was obtaied in these complex systems.
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发布时间：2021-03-19 - 摘要：he structures of the Crystalline 3,4-polyisoprene (3,4-PI) was inveshgated by using WAXD, SAXS and Lane photography in various polymerhahon condihons and elongation ratios. The results found that redudng reaction velodty of the catalyhc system is favourable for crystalline capadty. The polymeric structures depended markedly on content of nitrogen donor of the electric agent. The degree of crystailinity and long period inereased with increasing draw raho, but crystailite she decreased. The polymers used in the work belong to non-homogeneous particle system.The particle radiuses are 3.5-16.4nm.
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发布时间：2021-03-19 - 摘要：he reactivity ratios of the radical copolymerhation of tributylhn methacrylate (TBTM) with methyl methacrylate (MMA) in toluene solution at various temperatures have been measured by using FTIR method to analyze the copolymer composihons. The experimental resultS have been calculated by Fineman-Ross (FR) linear equahon, Mayo-Lewis (M-L) curve-fitting, Error-invariables Method (EVM), The eftfch on the reasonability and predsion of r1 and r2 of various calculahon methods have been discussed. The linear relation has been obtained from lnr vs. 1/T. The reasonable values r1 and r2 at various temperature should be on the the lines. These reactivity ratios are the best data input with the smallest statistical error. The results show the copolymerization of TBTM with MMA tend to be the ideal copolymerization with the copolymerization temperature increasing.
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发布时间：2021-03-19 - 摘要：The combined edniques of lamellar decoration and ruthenium tetraoxide staining have been uest to reveal molecular director orientation around the disclination in the frozen nematic state of polymers by transndssion electron microscopy. All six discllnations with strength S=±1/2 and S=±1 in the nematic mesophase of a thermotropic aromatic copolyester have been observed. It is also observed that every disclination, interacts and is connectal with its neighbouring disclination to form in pairs of the disclination.
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发布时间：2021-03-19 - 摘要：Heating press films of alloy of polystyrene with poly (styrene-butadiene) rubber were measured by the thermally stimulated current and small-angle X-ray scattering and the compatibility on alloy was discussed. Small-angle X-ray scattcring was interpreted in terms of the Porod Law which leads to values for interface layer thickness (compatibillity zone). The relation with compositions of alloy was discovered. A correlation distance and invariant Q were calculated by Debye-Bueche theory. A cormlation distance represents the mean-square electron density fluctuation and thermogeneity of alloy was analyzed using invariant Q. Solvent-cast films of alloy were measured by transmission electron microscopy,and the phase distribution of alloy was investigated.
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发布时间：2021-03-19 - 摘要：electing Acrylamide (AM), Acrylamide/Sodium Acrylate (AM/SA) and Acrylamide/(2-methacryloyloxyethyl) trimethylammonium chloride (A M/D M. M C) as the monomers, we inveshgated the inverse ndcroemulsion polymerization under the same condihons and got the kinetic equations. In this paper, the results are discussed.
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发布时间：2021-03-19
Research Article
- 摘要：The α-double bond and ω-carboxylic-tCndnated PEO macromer was synthesize suansfully and based on study of radical copolymendhon between PEO macromer and MMA., A series of reactive poly (methyl methacrylate)-g-tooly (ethylene oxide)-COOH) (PMMA-g-(PEO-COOH)) with different PEO contents was synthsind. The obtained produCts exhibited expected structure as indicated by IR, H-NMR, GPC and so on. The result of reaction betWeen PEO-COOH and amino add demonstrated that PEO-COOH exhibited the expeCted reactivity. The above results provide useful knowledge for the further study of the reaction between PMMA-g-(PEO-COOH) and bioactive materials.The solution behavior of thegraft copolymer was also reported.
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发布时间：2021-03-19 - 摘要：During the initial stage of pyrolysis of polydimethylsilane, larger quanhties of gaseous and liquid products are produced. In this paper, it is proved that the gaseous product contains dimethylsilane and trimethylsilane, whereas liquid products is a future of linear or cyclic silane oligomers by IR and GC-MS analysis. Baed on the idenhfication and analysis to the composition and structure of these pyrolytic products, the pyrolytic process and mechanism of polydAnethysilane are discussed.
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发布时间：2021-03-19
Research Bulletin
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