最新刊期
卷 ， 期 3 ， 1991
- 摘要：The error analysis of the method for estimation of weight average molecular weight ofpolymer sample from the intrinsic viscosity, and GPC chromatogram of normal distributionshape was discussed in this paper. The error analysis and experiment result showed that the ralative error of weight avarge molecular weight of polymer sample was not more than 10% by the method proposed in refrence (3), when 0.6
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发布时间：2021-03-19 - 摘要：An additional humidity-induced TSE peak appears in medium temperature region, the LD-PE specimens were exposed to humid air for certain time, before or after poling, even then kept in vacuum of about 0% RH for 72h after poling. This peak can be associated with thermal release of trapped ions in amorphous-crystalline interface.An analysis on TSC spectma of LDPE specimens with inorganic filler, dried or wetted before poling suggests that the inorganic filler (kaolin with surface treatment) and absorbed water molecule in LDPE could be considered as electron accepter,the former as shallow trap of electron,the latter as deep trap of electron.
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发布时间：2021-03-19 - 摘要：A series of new polymeric pseudo crown ethers contained many oxyethylenes have been synthesized by polycondensation of polyethylenglycol diphenyl ethers which was prepared by phenol and chlorides of polyethylenglycol with formaldehyde in the formic acid and in the presence of inorganic acid. The new monomers and polymers have been determined by IR, UV,1H-NMR, MS and element analysis.The complexing capacity, enrichment efficiemcy for metallic ions and thermostability of the polymeric crown ethers have also bbeen investigated. The results of the experiments indicated that all of the polymers can be used under 160℃ and that enrichment efficiemcy of the polymer-6 for K+,Pb2+,Ag+,Fe3+(10-6-10-4mmol/ml) is approximate to 100%. These polymeric false crown ethers can also be used in organic reactions as a phase transfer catalyst or absorption of NaBH4.
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发布时间：2021-03-19 - 摘要：Azo coupling method is employed in the synthesis of polystyrene copolymer with high second order nonlinear optical activity azo dye side chains which contain dicyanovinyl as electronic acceptor and alkylamino group as donor. The characterizations of copolymer show that the chromophore contents are over 40 mol%. Copolymer is soluble easily in organic solvents such as acetone, THF,and uniform film is obtaind.
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发布时间：2021-03-19 - 摘要：Urushiol-aluminium chelate polymers were synthesized by reaction of urushiol and aluminium chloride. Polymers with different aluminium content were obtained through different urushiol-AlCl3 molar ratios. IR spectra showed that new peaks appeared at 580-660 cm-1, and peake at 3200-3500 cm-1 greatly weakened, We can conclude new compound was formed after, reaction. The weakness and disappearance of double bond absorption indicated the urush-iol-aluminium chelate converted to polymer during reaction. MS results showed urushiol and AlCl3 formed chelate compound initially. Coatings made from these chelate polymers possess-ing excellent physico-mechanical properties and good heat-stability.
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发布时间：2021-03-19 - 摘要：The polystyrene (PS) substrates were treated by the plasma at different time (0.5, 1,3,6,15, 30 and 60 minutes) and power (10,20,60,100,150 W) in the Ar, N2, O2, H2 and air.The surface compositions, structure and states of the polystyrene are characterized by X-ray photoelectron spectroscopy (XPS)We have found that large amounts of O and N atoms as new structure are incorporated into the polymer surface by the plasma treatment.We have observed that functional groups, such as C-O, C-NH2 C=O, COOH and O- C - O-O were introduced to surface of polystyrene under these conditions. The depth profiling can be accomplished by controlled erosion of the surface Ar+ sputtering. The shake-up stallite peak (291.7eV) for the polystyrene can again be present after Ar+ sputtering 60 A.
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发布时间：2021-03-19 - 摘要：In this paper a process for the preparation of maleic anhydride-containing polyethylene is stated, When the reaction of maleic anhydride with molten polyethylene in the presence of radical catalyst is in progress, the crosslinking reaction beween the polyethylene molecules is simultaneusly produced. This crosslinking reaction will increase the viscosity of the melts and give rise to bed rheological property.The addition of some special additive can effectively prevent the crosslinking reaction, but not affect evidently the graft rate of maleic anhydride on the polyethylene,it can amelirate the rheological property and the processing property of the system. The maleic anhydride-containing polyethylene not only can be compatible with the polye-thylene,but also can be coupled with nylon, as a excellemt interfface compatibilizer. It can make notched Izod impact strength at 0℃ of the nylon 6-polyethylene blend incease 4 times over the blend without the additive.
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发布时间：2021-03-19 - 摘要：The β-relaxadon of PEN in Thermally Stimulated Current (TSC) is firstly reported in the present paper. The effects of the variation of electrode materials and polarization field strength on TSC peaks indicate that the β-relaxation is due to the dipolar contribution. The effects of the crystallinity variation on the 3 peak current and on the activation energy of the β-relaxation further indicate that the molecular origin of the β-relaxation is the local segmental motion of PEN chain in the amorphous region.
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发布时间：2021-03-19 - 摘要：The influence of various promoters such as silicon compounds and C6H5MgCl on the co-polymerization of ethylene with butene has been described. The kinetics of copolymerization with MgCl2-supported TiCl4 catalyst has been investigated. The results show that rate of the copolymerization can be expressed asMonomer reactivity ratio, sequence distribution and composition of the copolymer were determined by 13C-NMR spectra.
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发布时间：2021-03-19 - 摘要：The crystallinity of ethylene/a-olefin copolymers, which was prepared by copolymerization of ethylene and a-olefins with heterogeneous Ziegler-Natta catalyst made by chemical reaction, was studied by WAXD, DSC, and PLM methods.The results of WAXD showed that the crystallite size and degree of crystallinity decrease and the parameters of unit cell increase with increase content of a-olefin in copolymers. On the other hand, the crystallite size and degree of crystallinity of the copolymers after heat treatment obviously increase,while parameters of unit cell decrease. Both the critical crystalline sequence lengthes and the value of k obtained increase in the order of EPe
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发布时间：2021-03-19 - 摘要：The exponent of concentration in viscosity-concentration power law, =K.ca have been studied for the concentrated solutions of the sulfonated polysulfones with different degree of sulfonation (IEC = 0~0.93 mmol/g) in 3 dimethylformamide/toluene (3/1 volume ratio) mixed solvents without and with added salt (0.07 mol NaNO3) at 30℃.The exponent decreases with increasing degree of sulfonation in salt solution (a = 4.29 ~ 3.52), and was consistently higher in salt-free solution (a = 4.09~3.03). And the results were discussed with a scaling approach.
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发布时间：2021-03-19 - 摘要：The monodisperse copolystyrene-divinylbenzene crosslinked microsphere with diameter more than 3μm has been synthesized by improved seed polymerization. The monodisperse polystyrene seeds with diameter 1-2μm were obtained by emulsifier-free polymerization. And the effects of swelling conditions such as the swelling temperature, the volume ratio of swelling agent to seed emulsion, swelling time and the crosslinking agent, the small molecular compound, the emulsifier on the particle size and the particle size distribution have been studied.
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发布时间：2021-03-19 - 摘要：The copolymerization of propylene with 1-octene over TiCl4/MgCl2-Al(i-Bu)3 system has been studied. It was found that the catalytic activity is higher in the case of copolymerization than that of homopolymerization. As the 1-octene concentration increased in copolymerization, the hrxane-insoluble fraction decreased and crystallinity of copolymer decreased to 1%. The monomer reactivity ratios were determined as rp=5.63 and r0=0.32. The monomer composition and sequence distribution of the copolymers were determined by IR and 13C-NMR.
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发布时间：2021-03-19 - 摘要：The aggregation structure of carboxylated poly(2,6-dimethyl 1,4-phenylene oxide) (CPPO) ionomer has been studied with DSC, dynamic mechanical thermal analysis (DMTA), WAXD and SAXS techniques. The results of DSC predict that there exist a critical concentration for CPPO ionomer, and Tg increases dramatically up to cation concentration of 5mol%. A relaxation peak corresponding to the relaxation of ionic microphase structure appears beyond the Tg region by DMTA measurement. SAXS provided a powerful evidence that there exists ionic clu-sters in CPPO ionomer,and the dimension of these ionic microphase domains are about 30A which is independent of the cation concentration.
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发布时间：2021-03-19
Research Article
- 摘要：The polysaccharide of lentinus edodes and polytictus versicolor has been fractionated by repeated precipitation method.All fractions and the unfractionated samples have been characterized by rapid dynamic membrane osmometry. For its aqueous solution, the second virial coefficient A2 decreases as the molecular weight increases. The relationship is A2= 2 slope (MnRT)-1/2.Determination of the distribution curve by means of fractional precipitation. Separation of a polysaccharide into six fractiona by a fractional precipitation carried out. The distribu-tion-curve of integral and differential is obtained. After according to the modified Elias'cloud-point titration method and using an Abbe's refractometer to define the clou-point,[6-]8it was found that water/acetone (89:11 by vo-lume) is a θ solvent for the polymer at 25±0.05 C. For θ conditions,the intrinsic viscosities were determined by capillary viscometry. Thus a monodispersed [n]-M relationship has been obtained: [n]θ=2.59×10-2M0.509 From the result above the unperturbed dimensi on(r2θ)1/2 was found to be 4.7×10-9M1/2.
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发布时间：2021-03-19 - 摘要：The surface properties of segmented polyether polyurethanes (SPEU) were studied by contact angle technique in this paper. Surface contact angle is measured by Kealble method and interfacial free energy is studed by the air/octane bubble method. It is revealed that "soft" Polyether PTMG and PEG have different effects on the air-facing surface and water-facing surface. The segment PEG component can decrease SPEU-water interfacial energy effectively and change the friction ratio vp/vd of surface energy of SPEUs.
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发布时间：2021-03-19 - 摘要：A new rare earth catalyst system was found in our laboratory. Not only styrene and iso-prene are copolymerized but also styrene and butadiene are copolymerized with the new catalyst system-4f metal compounds-alkyl aluminium compounds-other components. The copolymers are characterized as the block copolymers containing 4.0-4.5(%) gels, 22.0-97.7(%) cis-l,4-contents and 8.3-79.8 (mol%) styrene contents by means of IR, 1H-NMR,13C-NMR and Dynamic mechanic properties.
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发布时间：2021-03-19 - 摘要：This article describes the photoinitiated cationic copolymerization of 1,6,8,13-tetraoxaspiro [7,7] tridecanes (SOC7), unconstrictive monomer, and 3,4-epoxycyclohexylmethyl 3,4-epoxycyc-lohexane carboxylate (ERL-4221). The test results show that the addtion of a small amount of SOC7 to ERL-4221 system results in suppressing shrinkage without significantly degrading the thermal properties. The proper mol ratio of ERL-4221 to SOC7 is 4:1. A crosslinked copoly-mer having Tg 230℃ and volume shrinkage below 4.4% on photocopolymerization is obtained. The elemental analysis, FT-IR and 1H-NMR spectra were shown respectively for characteri-zation of the photocopolymer.
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发布时间：2021-03-19 - 摘要：The Raman scattering on a novel liquid crystal side chain polymer, poly-2,5-bis (p-meth-oxybenzoyloxy) styrene, has been performed. We observed that the characteristic Raman sp-ctra of the vinyl group in the monomer changed much deeply in the polymer, especially for the Raman line correponding to the C=C of the vinyl group which disappeared completly in the polymer. Contrast with that, the Raman spetra of the rest group did not present any substantial difference between the monomer and the polymer. These experimental facts show-ed that the vinyl group of the monomer was tranfered to the polymeric backbone while the chemical structure of the mesogenic unit in the monomer remained after the polymerization,and also conformed that it was successful in the synthesis of a liquid crystal side chain plymer without a flexible spacer between the mesomorphic unit and the molecular main chain.
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发布时间：2021-03-19 - 摘要：The interaction of mixed polyether polyester blockcopolymer (MPEE) and 1,4-dicarbaz-ylcyclobutane (1, 4-DCC) in the excited state and the ground state has been studied by measurement of fluorescence spectra. The results show that the fluorescence spectrum of 1,4-DCC was quenched by MPEE by formation of exciplex in chloroform solution. The quenching effect is folowing Stern-Volmer equation. Kq is obtained (7.0 ×109mol-1s-1) from S-V plot and r value of 1,4-DCC. Not only the monomer band of 1,4-DCC but also the exciplex hand of 1,4-DCC and MPEE were observed in the film of MPEE in which 1,4-DCC was dispersed. The co-mplexation of 1,4-DCC and MPEE in the ground state was proved by the appearance of long wavelength band in excitation spectrum. Analogously the quenching effect of dimethyl tereph-thalate (DMTP) and ethyleneglycal-p-phthalate (EGP) which is used as a model compound of hard segment of MPEE has been studied too. Furthermore. 1,4-DCC could be used as a flu-orescence probe molecule of MPEE. The structure and morphlogy of MPEE could be studi-ed by fluorescence technique.
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发布时间：2021-03-19 - 摘要：The epitaxial crystallization of highly oriented films of IPP/HDPE blends has been studied in this work by means of trasmission electron microsscopy. When the content of HDPE in the iPP/HDPE blends is below 30%, epitaxial growth of HDPE lamellae on highly oriented IPP lamellae has been observed. The intercrossing angle of the two kinds of epitaxial lamellae is about ±45°,while the contact planes should be (010) of IPP and (100) of HDPE. There is no above relationship epitaxial crystallization in the films when the content of HDPE in the blends is over 40% because of the formation of independent domain of HDPE.
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发布时间：2021-03-19 - 摘要：The effect of irradiation temperature on radiation crosslinking behavior of polyetherketone with cardo group (PEK-C) were studied. A expression calculating the crosslinking parameter (B) of PEK-C.were established.β volue obtained by this expression is in agreement with β experimental value.
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发布时间：2021-03-19
Research Bulletin
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