最新刊期
卷 ， 期 5 ， 1993
- 摘要：Radical polymerization of 14 kinds of different dialkyl fumarates (DRFs) in the presence of AIBN and BPO were studied. It has been found that all DRFs monomers can undergo ho- mopolymerization in the presence of free radical initiators. The polymerization reactivities of DRFs increase in the following order: DCHF>DtBF>DiPF>MiPF, DEF, DsBF, DsAF> DEHF>DnHF>DiBF, DiAF, DnPF, DnBF, DnAF. This phenomenon was explained on the basis of analysis of DRFs monomers structures. Structures of DRFs polymers as well as their properties were characterized by means of IR,1H-NMR etc.
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发布时间：2021-03-19 - 摘要：It was reported the group transfer block copolymerization of methacrylates and arylates with bifunctional initiators and bibenzoate catalyst. ABA-triblock copolymers of MMA and BA, MMA and BMA, MMA and EMA with predetermined molecular weight and low poly-dispersity were obtained. The copolymers were characterized by 1H-NMR, GPC and DSC. The effects of the block sequence, catalyst concentration, solvent polarity on block copolymerization were studied.
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发布时间：2021-03-19 - 摘要：Polyurethane/methyl methacrylate copolymer interpenetrating polymer networks with opposite charge groups (ionomer IPNs) were synthesized from NPU and PMMA-MAA, NPU was prepared from poly(oxyethylene) glycol, 2,4-tolylene diisocyanate and bis (2-hydroxy ethylene) butylamine, PMMA-MAA was prepared by copolymerization of methyl methacrylate and methacrylic acid. The results of kinetics study showed that the formation rate of ionomer IPNs was slower than that of usual IPNs, the polymerization rate of two networks restrained one another,and increased with concentration of ionic bond. However,the poly-merization mechanisms of two networks were not affected.
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发布时间：2021-03-19 - 摘要：The polymerization of propargyl alcohol catalyzed by triethylamine was carried out for the first time. Some features and the kinetic behavior of the polymerization have been investigated. Poly (propargyl alcohol) obtained is a brown sticky-solid with lustre, and shows semi-conductivity and paramagnetism.
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发布时间：2021-03-19 - 摘要：In the copolymerization of ethylene and propylene with Ziegler-Natta catalyst VOCl3/ Et3Al2Cl3, when CCl4 was used as polymerization solvent, there occurred a sudden color change in the polymerization process. After the color change, low molecular weight polymer was obtained. Structure characterization and mechanism study showed that, after the color change, new active center formed and polymerization changed from coordination to cationic mechanism.
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发布时间：2021-03-19 - 摘要：The preoxidizing process of polyacrylonitrile (PAN) fiber is investigated with in-situ X-ray diffraction techniques in this paper. Through experiment, we determined the curve of wide angles diffractering intensity. From the resolution charts which were gained of different times from the determination of PAN WAXD(wide-angle X-ray diffraction), one can calculate the crystallinity, the microcrystalline sizes, the spacing of lattice and the "aromatization index" values for the samples. And all this, these parameters with transient case of the change of the experimental condition were discussed in detail. Simultaneously. the bethaviour of the cyclizatic kinetics during the processing of PAN fiber to preoxidized fiber was described. The rate constant of cyclization reaction and the activation parameter of cyclization at each temper-ature were calculated. The studies of these structural parameters and kinetics may provide some fundamental information for the optimizing control for the industrial process of the high-performance PAN-based arbon fibers.
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发布时间：2021-03-19 - 摘要：Miscibility of blends of styrene-butadiene-styrene triblock copolymers SBS-48,SBS-30, SBS-28 and poly (vinyl methyl ethyl ether) (PVME) were investigated by clarity ,DSC and FT-IR. From optical clarity and DSC results, the higher the styrene content in SBS and the higher the molecule weight of PS segment were, the better the miscibility of the blends was . From FT-IR results, the relative peak intensity of the 1100 cm-1 region due to COCH3 bond of PVME was sensitive to the miscibility of SBS/PVME, while the peak position of 698 cm-1 re-gion due to C-H out-of-plane bending vibration of phenyl ring in PS was not as sensitive as that in PS/PVME.It can be concluded that the miscibility in SBS/PVME blends is greatly af-fected by the composition of the block copolymers in blends and the composition of styrene in the copolymers. Molecule weight of PS segment in SBS is also important.
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发布时间：2021-03-19 - 摘要：The polysaccharide of pycnorus cinnabarius was prepared, fractionated and characterized. By using the water as solvent and the alcohol as precipitant, six fractions of polysaccharide were obtained. All fractions and the unfractionated sample have been characterized by dynamic osmometry, VPO, ultracentrifugation, light scattering and gel permeation chro-matography. Modified Elias cloud-point titration method with a UV speclrophotometer was used to determine the cloud-point. It was found that water/acetone (89.82:10.18 by volume)is a θ-solvent for the polymer at 25℃. The relationships between molecular weight and intrin-sic viscosity[η],unperturbed chain dimension,Second Virial coefficient A2 of polysaccharide in a θ-solvent at 25℃ were as follws From the result above the unperturbed dimension(h) was found to be 1.21×10-9M1/2(cm).It was found that the polysaccharide has the styomgest inhibition effect on S180 in mice. The relationship between the antitumour activity and their solubilities in water was dis-cussed.
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发布时间：2021-03-19 - 摘要：Using SPAN-OP composite emulsifier and K2S2O8Na2SO3 redox initiator ,the inverse mi-croemulsion copolymerization of (2-methacryloyloxyethyl) trimethyl ammonium chloride (DM. MC) and acrylamide (AM) was developed. The monomer reactivity ratios are rDM.MC= 1.11±0.16 and rAM = 0. 53±0. 08. Under the conditions of total concentration of monomer being 20%-40%(wt), initiator concentration being 0.01%-0. 05%,emulsifier concentration being 10%-18% and polymerization temperature being 299 K,the kinetic equation of copolymerization can be expressed:Rp=k[M]1.07[I]0.52[E]0.90.In this paper,above results were explained.
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发布时间：2021-03-19 - 摘要：A new kind of polythioether type cotton fibers was synthesized by the reaction of cotton with chloromethylthiirane. These fibers had a high adsorption percentage (≥99%) for the Au (Ⅲ) and Pd (Ⅱ) in low concentration (0.1 mg/ml) and moderate sorption capacity for Ag ( I ), Au( Ⅲ) and Pd(Ⅱ) ,but rather low for Pt( IV ) . They adsorbed Cu( Ⅱ ) ,Zn( Ⅱ ) and Pb (Ⅱ) hardly. In the mixture of Au(Ⅲ )-Pd( Ⅱ)-Pt( IV )only Au( Ⅱ ) and Pd(Ⅱ ) were adsorbed.
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发布时间：2021-03-19 - 摘要：The crystalline morphology of a thermotropic aromatic copolyester with flexible spacer has been studied by microscopy techniques. Spherulites morphology under polarizing microscope were observed for solution cast specimens. They were composed of radially growing crystalline lamellae of thickness around 10 nm. It was found that the molecular chains are oriented in the thickness direction . The influence of molecular chain rigidity on crystalline be-hayior of aromatic copolyester has also been studied. Results indicate that the crystallinity of materials increases with increasing the molecular chain rigidity.
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发布时间：2021-03-19
Research Article
- 摘要：The kinetics of non-isothermal crystallization of Nylon-1010 has been investigated by using differential scanning calorimetry (DSC),DSC curves were obtained under cooling rates (R):2. 5, 5.10,20, 40K/min. Applying Mandelkern and Ziabicki Theories, the values of the Zc and Gc-the kinetic crystallizability have been determined. The exponents of Avrami obtained in this work decrease with the increase in cooling rate and then remain at a definite value. The experimental results analysed show disagreements with the increase in cooling rate and then remain at a definite value.The experimental results analysed show disagreements with the Ozawa equation.
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发布时间：2021-03-19 - 摘要：In this paper, the relationship between the copolymerization crosslinking condition for the acrylamide and N,N' -methylene-bis-acrylamide containing a large amount of bentonite in alkaline solution and the water absorption of the partially hydrolysed crosslinked polyacryla-mide was studied. The intensity and the structure of gel were measured.It was found that the intensity of the partially hydrolysed crosslinked polyacrylamide containing bentonite after absorbing water is many times larger than that of one without bentonite.
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发布时间：2021-03-19 - 摘要：HTPB used for propellant contains trace epoxy group which has a great effect on the mechanical properties of the products made from HTPB. By using 13C-NMR method in this paper, chemical shift of the goups in 13C-NMR spectra was first assured and the amount of the epoxy groups and the distribution of the hydroxyl in HTPB were obtained by measuring various samples. For the first time .three -unidentified peaks in 13C-NMR spectra of domestic samples were found. The contributing factors and the structure of these peaks were discussed.
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发布时间：2021-03-19 - 摘要：The monomer-solubility and polymer-transparency phase diagram of the three tri-component system were determined. It was found that in system of Pb(MA)2-MA-St, monomer solubility is good and the copolymer has a large transparent region ; In system of Pb(MA)2-MA-MMA,monomer solubility is good but the transparent region is very small;In system of Pb(MA)2-MMA-St, monomer solubility is bad and the copolymer is also opaque. In the transparent region ,the nD and vD of the copolymer was determined, the refractive index of polymer component nDP[Pb(MA)]=1.626,nD(PMA)=1.499 was obtained indirectly and the refractive index in whole transparent region was estimated.
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发布时间：2021-03-19 - 摘要：The macromolecular reaction is one of the important basic methods for synthesis of functional polymers. Being used for resolution of a-amino acid enantiomers, ten different poly (ethyl o-methacrylate) containing chiral a-amino acid ligands were prepared and the SN2 reaction mechanism was discussed in detail. The effects of the property and amount of solvent, the types and concentration of a-amino acid, the temperature and time of reaction and the base catalysts on the SN2 reaction were also discussed.
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发布时间：2021-03-19 - 摘要：Two new vinyl monomers, N-(p-hydroxymethyl phenyl) carbazole acrylate and N-(p-by-droxymethyl-phenyl )-carbasole methacylate, were synthesized. The polymerizations of two monomers have been studied by different conditions. The structures of monomers and polymers were examined by Elemental analysis, IR, 1HNMR and UV spectroscopys. The molecular weights of polymers were determined by dynamic osmometry.
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发布时间：2021-03-19 - 摘要：A new biodegradable Poly (e-caprolactone)-Poly (ethylene glycol) block copolymer (PCL-b-PEG) has been synthesized by co-polycondensation reaction of e-caprolactone (e-CL) and poly (ethylene glycol) (PEG) in the presence of Ti(OBu)4 catalyst. The composition,hy-drophilicity and crystallinity of the copolymer can be controlled by changing the feeding dose of reaction system. The degradation rate of the PCL-b-PEG copolymer is improved by introducing the PEG segment, and the more the PEG content in the copolymers,the faster the degradation rate of the copolymer.
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发布时间：2021-03-19 - 摘要：A liquid crystalline polysiloxane has been prepared by a hydrosilation reaction of poly (methylhydrosiloxane) with (p-((4-allyloxy)benzoxy)benzoxy)-4-methoxyphenyl. The chemical structure of the monomer and polymer was confirmed by IR and 1H-NMR analysis, and as many as 13% α-addition isomeric side chains were found from the NMR spectrum of the polymer. In addition ,the phase behavior of the monomer and polymer were studied by optical polarized microscopy and DSC measurements.
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发布时间：2021-03-19 - 摘要：The relationship between the microstructure developed during injection molding of a PES/TLCP blend and its properties was investigated . The resulting injection molded structure had a distinct skin-core morphology, where TLCP fibres composed the skin layer and sherical and ellipsoidal particles or "stalamite"ones comprised the core section . The blend exhibits excellent mechanical properties due to in situ formed fibers of the disperse TLCP phase in PES matrix. The blend tensile strength reduces with increasing the melt temperature and the shear rate.
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发布时间：2021-03-19 - 摘要：Copolymerization of ethylene with linear 1-alkenes in the presence of different Ziegler-Natta catalysts, TiCl3-AlEt2Cl,VOCl3-Al2Et3Cl3and Ti(VMgCl2-AlR3 ,at 30℃ were investigated, and reactivity ratios for all pairs ethylene-1-alkene were determined . It was found that, for heterogeneous catalysts, the copolymerization reactivity of linear 1-alkenes was greatly improved when a small amount of propylene was present in the polymerization, while for homogeneous catalyst VOCl3, no change was observed. It seems that a synergistic effect exizted in the reactivities of propylene,linear l-alkene and active site in the polymerization with ethylene.
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发布时间：2021-03-19 - 摘要：Two N-acrylic monomers having phenothiazine moieties , N-acrylyl-2-chlorophe-nothiazine ( I ) , N-acrylyl-2-acetylphenothiazine ( I ) were synthesized and their polymers were obtained by free radical polymerization . The fluorescence study showed that at the same molar concentration of the chromophores, the fluorescence intensities of the polymers were much stronger than that of the monomers. This would be explained by what we called "Structural Self-quenching Effect. " The Stern-Volmer constants of the polmers quenched by several electron defecient vinyl monomers were obtained. The results indicated that their quenching efficiencies were relevant to the degree of the electron deficiency of the double bond.
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发布时间：2021-03-19
Research Bulletin
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