最新刊期
卷 ， 期 4 ， 1985
- 摘要：Four new polyesters containing 5-fluorouracil in the main chain were prepared by reacting potassium salt of 5-fluorouracil with ω-chloroalkyl chloroacetates. The chemical structures of these new polyesters had been confirmed by 1H-NMR, IR and elemental analysis. The antitumor activity of one of these 5-fluorouracil containing polyesters, Ⅱ-4 was tested against sarcoma 180, HSC in mice. It showed good antitumor activity and low toxicity. Blood concentration measurements of PFUE-Ⅱ-4 after oral administration to rabbits demonstrated that 5-fluorouracil containing polyester has a longer duration of action than that of low molecular weight drug FT-207.
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发布时间：2021-03-19 - 摘要：The procedure of treatment of data obtained by coupling GPC with capillary vi-scometer was discussed in detail. Methods and mathematical formulas for correcting the effect of the dead volume of the connecting tube and the residual volume of the syphone tube on the intrinsic viscosity and its correlation with elution volume were given. With the aid of the theoretical relationship between the experimental relation [η] (V) and the calibration function [η] (VR) for the monodisperse species, the separation and the column dispersion of the GPC columns used were calibated simultane-ously with narrow MWD polystyrene samples by coupling technique.
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发布时间：2021-03-19 - 摘要：It was found that the addition of compounds containing one nitrogen atom, such as pyridine, does not raise the catalitic activity in the polymerization of butadiene for the system of FeCls-(i-C4H9)3Al, and that the compounds containing two nitrogen atoms can incease the activity in the following order: 1, 10-phenanthroline>2, 2'-dipyridyl >> ethylenediamine or tetramethyl ethylenediamine. The polymerization of butadiene in the presence of FeCl3-(i-C4H9)3Al-phenanthroline have been studied in more detail. A possible mechanism is proposed.
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发布时间：2021-03-19 - 摘要：The dicationically living chains can he prepared by the hulk polymerization of tetrahydrofuran initiated by sebacoyl or adipoyl chloride-silver perchlorate at 0-50℃ without chain termination and transfer reactions. The initiator efficiency is close to one. The polymerization using succinyl chloride-silver perchlorate as catalyst gives only monocationically living chains.
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发布时间：2021-03-19 - 摘要：The preparation of polyepichlorohydrin substituted by imidazole from polyepiehlo-rohydrin and lithium imidazolide in aprotic dimethyl sulfoxide was proved successful. These polymeric ligands coordinate with CuCl2 in alcoholic solution rapidly and tend to form complexes with Im/Cu molar ratio equaling to 4. All macromolecular complexes obtained are insoluble in coommn solvents, and in the presence of them, the oxidative coupling of 2,6-dimethylphenol in dichlorobenzen-methanol(6.5/1, V/V) shows both "cooperativity"and "substrate inhibition". So, the reaction takes place by a enzyme-like mechanism.
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发布时间：2021-03-19 - 摘要：The wholly aromatic four-component copolyesters were prepared from p-acetoxy-benzoic acid, hydroquinone diacetate, 2,6-naphthalene dicarboxylic acid and isophthalic acid by melting polycondensation. The melted copolyesters exhibit good liquid crystal-linity in some range of the copolyester compositions.The relationship of composition and properties, DSC thermogram characters and mesomorphic behavior were discussed.
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发布时间：2021-03-19 - 摘要：Some organosilane polymers with high molecular weights have been synthesized by cocondensation of organosilicon dihalide monomers with sodium metal in toluene. These polymers are readily soluble in common solvents and can be molded, easted into films or drawn into fibers. Upon exposure of the solid polymers to ultraviolet light the polymers tend leads to produce degradation or crosslinking.
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发布时间：2021-03-19 - 摘要：In this paper technique of Thermally Stimulated Creep is applied to TSC, and simplification has been made. Results show that the wide spectrum of polymethylmetha-crylate observed by common TSC, has been resolved with success into many spectra of relaxation units. This method of resolving spectrum is based on change of interval of poling temperature. Therefore it is called poling temperature scanning method of TSC.
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发布时间：2021-03-19 - 摘要：The pyrolytic process of polyehlorotrifluoroethylene (PCTFE) in air was studied by using TG-DTG methos. The kinetic parameters were obtained by using the various kinetic approaches and the results were applied in order to evaluate the various kinetic theories and explain the variation of the activation energy during the pyrolytie process in the extent of 5-95% pyrolytie degree. The random pyrolytic mechanism was proposed according to the relations between the pyrolytie extent and rate of pyrolysis. We seccessfully explained the structures of pyrolytic products of PCTFE which ap-peared in recent literatures,and we also verified the experienced equation of bond dissociation energy proposed by Errede is inappropriate to PCTFE at least.
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发布时间：2021-03-19 - 摘要：The 13C-NMR, spectra of alternating copolymers of conjugated dienes, e.g. butadi-ene(BD), isoprene(IP) and chloroprene(CP), with methyl acrylate(MA) were studied. It was proved that they are all alternating copolymers. The BD units in poly(BD-a-Ma) are mainly in the form of trans-1,4-structure. The contents of trans-1,4-, cis-1,4- and 1, 2-structure are 88, 7 and 5%, respectively. The IP and OP units in poly(IP-a-MA) and poly(CP-a-MA) are present essentially in trans-1, 4-configuration and link with MA units predominantly in the "head to head"arrangement while CP-CP units pre-sent in the latter with a small quantity.
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发布时间：2021-03-19 - 摘要：Spinodal has been derived from the chemical potential of the Flory equation of state theory. Also given are the temperature and pressure dependences of the equation of state parameters. Calculations show that the Flory theory describes the compatibility behaviour of polymer mixtures as well as McMaster's modified treatment did.It is pointed out that previous work exaggerated the influence of molecular weight and the equation of state parameters upon phase diagram and predicted a narrow concentration region for phase separation on the assumption that X12=O and Q12=O,where X12 and Q12 are interaction energy and entropy parameters,respectively. For practical systems X12=O and Q12=O,the influence of these factors upon phase diagram and the shape of phase diagram will be predicated to be reasonable as compared with experi-ment.
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发布时间：2021-03-19 - 摘要：Two high molecular weight samples of poly(2-vinylpyridine) (P2VP) designated as 1 and 2 were spontaneously polymerized in diluted or concerntrated sulfuric acid. Their 13C-NMR spectra show that they are atatic polymer. Their intrinsic viscosity (shear rate D=0) molecular weight relationship has been obtained:[η]D=0 = 1.27×10-2 Mw0.70(in DMF, at 25℃, Mw: 2.66 ×10s-10.0× 106). Their highest intrinsic viscosity (in DMF, at 25℃), which is independent of shear rate, is 260ml/g, and M is about 1.74 × 106. The unperturbed dimension (R2>o/M) of P2VP is 6.08×10-18cm-2g.In DMF parameter B is 1.91×10-27cm-3.
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发布时间：2021-03-19
Research Article
- 摘要：The dinitriles Ⅰ-Ⅲ with benzofuran, benzothiophene andquinoline ring were synthesized. The polymerization rates of these dinitriles with 4 mole percent of zine chloride as catalyst at 300℃ were measured by infrared spectroscopy. The rate constants are 1.61, 2.63 and 3.09 l·mol-1sec-1, respectively. The TGA and isothermal weight loss at 371℃ in air of these three polymers were also measured, and the results indicated that the oxidative thermal stability of these polymers is not as good as that of the polymer of the dinitrile containing benzothiazole ring.
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发布时间：2021-03-19 - 摘要：Aliphatie tertiary amino-group N-substituted aerylamides．N-acrylyLN’-methylpipe-rasine (AMP) and N-methaerylyl-N'-methyl piperazine(MAMP) were synthesized dire-ctly．from N-methylpiperasine with corresponding acryl chlorides and characterized bly the elementary analysis of their picrates，1H-NMR,IRand MS. AMP did not poly-merize with benzoyl peroxide．but could polymerize with LPO．The rate equation of the polymerization was given as Rp=Kp [AMP]0.5 [LPO]0.5 and the overall activation energy of this polymerization system was determined as low as 10.8 keal／mol．The redox nature of LPO with the monomer itself had been suggested．The polymers of these N-substituted aerylamides display good antithrombogeneeity tested by reaeleifieation me-thod.
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发布时间：2021-03-19
Research Bulletin
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