最新刊期
卷 ， 期 1 ， 1989
- 摘要：Effects of vapour of organic solvents on the poly-(ethylene terephthalate) (PET) was studied by the differential scanning calorimetry (DSC). It is shown that solvents may be classified by its effect into the active solvent and unactive solvent, and then, according to change of cold crystal peak area, effects of unactive solvents on the PET may be classified into three types: unchanged, reduced behind time and quickly reduced. Duplex cold crystal peak was also observed in the DSC of PET by vapour of unactive solvents.
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发布时间：2021-03-19 - 摘要：A convenient method for the quantitative determination of terminal hydroxyl microstruc-tures in ethylene-propylene oligomer has been 'developed and evaluated by FT-IR spectroscopy. n-Amyl alcohol or 3-methyl-1-butyl alcohol and 2-butyl alcohol were used as model compounds to assign primary and secondary hydroxyl groups respectiyely. The 3640 cm-1 was selected as key band for measuring the primary hydroxyl group, and the 3623 cm-1 as key band for measuring the secondary hydroxyl group. By using 10 cm-1 path length cells and subtracting spectra to remove interferences of impurity in solution,it is suggested that a reasonalby accurate esti-mate of terminal primary and secondary hydroxyl group would be given by the equation;a=15.8667×103Cp+0.25674.Since the spectral bands of primary and secondary hydroxyl group overlat,the spectral bands were first resolved. By a program of RUN.CAPR in Nicolet FT-IR 170sx,area of repective band was integrated to determine microstructure of terminal hy-droxyl group.
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发布时间：2021-03-19 - 摘要：The polymerization of methyl methacrylate in aqueous solution is initiated by cupric polypropylene-graft polycarboxylate/sodium sulfite system. The overall polymerization rate can be expressed asThe polymerization is proceeded by free radical mechanism. The primary radicals are formed by the process of "complexation - hydrogen transformation" between cupric polycarboxylate/sodium sulfite/methyl methacrylate.
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发布时间：2021-03-19 - 摘要：This paper describes the synthesis and free radical polymerization of a new spiro-o-ester, 7-methylene-2-methyl-1,4,6-trioxaspiro (4, 4) nonane (MMTN). The polymer structure was determined by 1H,13CNMR spectra as well as elemental analysis. Results indicate that the polymer obtained by polymerization in bulk consists of structural unit VII, While a copolymer with unit Ⅶ,Ⅷ and IX was obtained in solution polymerization. Based on the polymer structure, polymerization mechanism was discussed.
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发布时间：2021-03-19 - 摘要：The unperturbed dimensions for a series of poly (methyl methacrylates) with Bernoullian distribution of stereochemical composition has been studied. A technique involving a gel permeation chromatography coupled with capillary viscometer was used for this purpose. The effect of the column dispersion of the GPC columns on the measurement of unperturbed dimension has been discussed. It has been shown that the experimental results are in good agreement with the values predicted by Monte Carlo calculation.A modified equation has been proposed to calculate the unperturbed dimension of the polymers with asymmetric substitutents and independent internal rotations. The parameters,K and a of [n]=KMafor a series of stereoregular PMMA in tetrahy-drofuran at 30℃ has also been determined.
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发布时间：2021-03-19 - 摘要：The ageing of rigid polyvinyl chloride (R-PVC) aggravated by nitric and sulfuric acids was studied by IR, UV Spectroscopy, thermo-analysis and molecular weight determination. It was found that a number of groups, such as -NO2, -ONO2, -ONO were incorporated into the backbone of the PVC chain. These groups cause the fransition reaction of the instable bonding between the stabilizers and the PVC chain. This not only changes the composition of the materials but also changes the physical conformation. The latter deeply influence the duration of P-PVC Products used in chemical environment.
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发布时间：2021-03-19 - 摘要：The photostabilising effect of polymeric hindered amine stabilizer (styrene-2,2,6,6-tetrame-thyl-4-piperidinyl mathacrylate copolymer) have been investigated in rhodamine 6G photosensitized degradation of cis-1,4-poly (butadiene). It have been found that the polymeric hindered amine stabilizer have properties of quenching singlet oxygen, decomposing hydroperoxide and scavenging macro-radicals produced during photooxidation and effectively protects cis-1,4-poly (butadiene) against singlet oxygen oxidation.The mechanism of photostabilization has been discussed.
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发布时间：2021-03-19 - 摘要：Poly (tetraphenylphenyl) methylsilane, polyvinylmethylsilane and their copolymer were investigated by means of X-ray photoelectron spectroscopy (XPS). Existences of (P-P)x,(P-d)x and (d-d)x in polysilanes could be characterized by XPS shake-up satellite peaks of C1s and Si2p. The order of ionization. potentials of various polysilanes have been also given by their XPS valence band spectra in this paper.
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发布时间：2021-03-19 - 摘要：The thermal stability of polydiorganosiloxanes (PDOS) was studied in the presence or absence of silicon-nitrogen compounds (S-N) and/or Ph2Si(OH)z, water in nitrogen. It was found that in the presence of certain S-N the weight loss of PDOS decrease from 18% to 1.5% and the residual molecular weight of PDOS increases from 5.4×105 before heating to 6.7×105 at 350℃ for 24 hr. On the contrary, the residual molecular weight decreases from 5.4±105 to 1.7±105 when in the absence of S-N. Experimental results show that the weight loss of PDOS increases from 18% to 65% in the presence of certain Ph2Si(OH)2 or water at 350℃ for 24hr., however,the weight can be decreased to 2-3% when the Ph2Si(OH)2 or water is added simu-ltaneously with the S-N to the PDOS. This means that the S-N can prevent siloxane chain degrdation caused by SiOH groups or water at high temperature. The S-N may play a role that removes SiOH groups and water in improving thermal stability of PDOS. This gives a simple method to obtain polyorganosiloxanes. resistant to temperature of 350℃.
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发布时间：2021-03-19 - 摘要：Six polysilanes which contain the units in the title were synthesized by sodium condensation of phenylethynyldichlorosilane with several other dichlorosilanes in toluene. The structures of these polymers were characterized by IR, UV and NMR spectra. Some complexes can be formed by the reaction of the polysilanes with strong electron acceptors. The new UV absorbance peaks of these complexes were found. The resistivities of the polymer bulks and the complexes were tested.
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发布时间：2021-03-19 - 摘要：Stereoregular polymerization of butadiene, initiated by catalyst system made up of Mocl2 and (i-Bu)2 AlOAr which are products of reaction of (i-Bu)sAl with various phenols, has been performed in hydroganated gasoline solvent. The effects of phenols structure on polymerization rate of butadiene have been studied. It was found that phenols having the electrondonating group can give a higher rate of butadiene polymerization than those having the electron-withdrow-ing group. The order of polymerization rate of butadiene goes as follows: bisphenol A>m-cresol>β-naphthol>phenol>p-chlorophenol. The overall activation energies Ea,the catalyst efficienceies a,the concentrations of active centers [p*],and the average lifetime of active cen-ters L have been determined at 40℃:Ea=71.2-94.2kJ/mole,a=1.1-3.5%,[p*]=0.8-2.5×10-5mole/1,L=30-63min.
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发布时间：2021-03-19 - 摘要：The effects of the drawing temperature, the drawing ratio and the drawing rate on the crystalline structure of β form polypropylene have been studied by DSC and X-ray diffraction. The results indicate that increasing the drawing temperature and the drawing ratio favor the transition of β-α form and the increasing crystallinity. The mechanism of β-α form transition of β form polypropylene during drawing and the effects of drawing on the microstructure have been discussed.
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发布时间：2021-03-19 - 摘要：The formation, texture and some properties of cyanoethyl cellulose (CEC)/dimethyl aceta-mide (DMA) mesomorphic solutions were studied. The solutions could transform from isotro-pic to anisotropic states through a biphasic range as increasing the concentration. The liquid crystal was cholesteric. Birefringence of the solutions increased with increasing the concentration or dropping of the temperature. The mesomorphic aggregates were composed of many domains whose orientation directions were different when the solutions were in nature. The liquid crystalline solutions which had been sheared could form"band-like"structure in which mole-cular chains oriented nearly along the lines of the shear. The orientatio directions of the molecular chains were different slightly between the neighboring bands.
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发布时间：2021-03-19 - 摘要：In this work, carbon fiber/nylon-1010 interfacial morphologies have been investigated by hot stage microscopy for single fibers embedded in nylon-1010 matrix. Results show that the ability for carbon fiber to cause nucleation of nylon-1010 producing transcrystallinity around fibers depends on the type of carbon fiber used and the highmodulus carbon fiber (M40) is more effective at nucleating nylon-1010 compared with the high-or middle-strength carbon fibers. The interfacial morphologies may be strongly influenced by the temperature and time of crystalliza-tion. The origins of these effects are also discussed.
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发布时间：2021-03-19 - 摘要：Flory's gelation theory and the nonequilibrium thermodynamic fluctuation theory have been used to predict the gelation time tg and the cure behavior after tgt of epoxy-triethanolamine system at various temperatures. The experimental results of the dynamic torsional vibration method showed there was a good agreement between the theoretical predictions and the experiments.
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发布时间：2021-03-19 - 摘要：The applicabilities of Tait and Murnaghan equations of state and Bridgman polynomial to isothermal compressions of 10 polymer solids have been examined up to 3 GPa at room temperature. Tait and Murnaghan equations are equivalent and their linear forms (6) and (7) are very accurately for multisegmentally fitting the isothermal P-V date of amorphous, semi-crystaline polymer solids with the universal values CT= 0.0894 for Tait and CM= 0.1016 for Murnaghan parameter, Bridgman polynomial can also be used but is inconvenient when there are pressure-induced transitions. Equation is also presented for Gruneisen parameter from Tait and Murna-ghan parameters.
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发布时间：2021-03-19 - 摘要：The monoclinic form of crystal in the room temperature-drawn high density polyethylene has been examined by Infra-red spectroserny and X-ray diffraction. The results show that the monoclinic form of crystal still exists in the specimens drawn at ligh fate even up 8.5 mm/s. It gives direct support to the peterlin's model for the mechanism of plastic elongation of semicry-stalline polymers.
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发布时间：2021-03-19 - 摘要：A new series of interpenetrating polymer network based on castor oil, toluene diisocyanate and hydroxyethyl methacrylate (HEMA) (Network I) and castor oil, TDI and polypropylene glycol (PPG) (Network II) was prepared. Their structure and properties were studied by solid NMR and dynamic mechanical analysis. Mechanical and dynamic mechanical measurements show that the tensile properties increase and tan 6 peaks broaden. Solid NMR results indicate that the interface ratio increase but it does not vary with relative amount of network I and net-work II whtch reveals that the samples might exhibit a core-shell structure.
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发布时间：2021-03-19 - 摘要：By detecting the contact angle in alkane/water/solid systems, the surface energy (ys) value of Al alloys after the surface treating, (FTIR surface analysis, TEM observation and EDXA element analysis) and the joint strength (t) of epoxy adhesive (EP)/A1 and EVA adhesive/Al systems were determined. The contributions of Ys to were discussed.
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发布时间：2021-03-19 - 摘要：Four new chelate resins (PB1-4) containing a polythioether backbone and dioxymonosulfur polyethylene polyimines in side chain were synthesized by the reaction of poly (2'-chloroethyl-2, 3-epithiopropyl ether) with polyethylene polyamines. The adsorption capacities of resin PB for metal ions such as Au(Ⅲ), Pd(Ⅱ), Pt(IV), Ag+,Hg2+, Zn2+ and Pb2+ were determined and compared with the corresponding resin PC containing polyether backbone. The experimental results showed that the resin PB, especially PB3 and PB4,possessed good adsorption ability for noble metal ions. The maximum adsorption capacities for Au(III),Pd(II) and Pt(IV) were 1.47,0.54 and 0.78g metal/g resin,respectively. But the capacities of the resin PC were much lower than that of the resin PB. It is obvious that polythioether mainchain in the resin PB plays an important role in adsorption of noble metal ions.
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发布时间：2021-03-19
Research Article
- 摘要：The thin film of bis (p-toluene solfonate) of 2,4-hexadiyne-l,6-diol monomer (TS) and its polymer PTS are successfully prepared by the classic Langmuir-Blodgett techniques. The X-ray diffractions reveal highly ordered structures in the films. The five diffracted peaks observed in the tange of 20 =5°-25° coincide well with those of (010) plane in TS single crystal. A trial has been made to prapare a mixed film of TS and arachdic acid, but complete phase separation occurs and TS molecules tend to form films preferentially.
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发布时间：2021-03-19 - 摘要：A series of immobilized cellulase were prepared by using polymethylacrylic acid (PMAA)-polyacrylamide (PAAm), polymethylacrylic acid (PMAA)-polyacrylic hydrazide (PAH) and polymethylacrylic acid (PMAA)-polyvinylamine (PVAm) interpolymer complexes. It was found that these immobilized enzymes have very high activity for transformation of cellulose to glucose. The cellulose conversion by PMAA-E-PAAm was about 40%. And these immobilized enzymes have an excellent stability and can be reused many times without any appreciable loss in catalytic activity. The immobilized enzyme activity was almost unchanged after storage for 30 days at room temperature.
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发布时间：2021-03-19 - 摘要：Acid-base interactions of the surface of MMA-natual rubber graft polymers in some liquids were studied by detecting the adhesion work and it's dispersion components. To the systems of the acidic liquid (phenol/tricresyl phosphate solution)-basic surface of graft polymers, acid-base interaction is present in interface. The contribution of adhesion work of this interaction, which did not take place in basic liquid (formamide)/graft polymer's systems, is increased with the increasing of the MMA content in this polymer. In addition,the adhesive strength of the joints of the graft polymer-glass substrate is also changed apparantly resulting from the difference of the acidic/basic property of the substrate obtained through surface treatment.
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发布时间：2021-03-19 - 摘要：Aniline, pyrrole and their derivatives can initiate photopolymerization of acrylonitrile and form charge transfer complex (CTC) with tetracyanoethylene (TCNE), their initiation rates and abilities to form CTC are related to the twist angle between the n orbit of nitrogen atom and the p orbit of benzene ring or pyrrole ring. The greater the twist angle, the lower the polymerization rate and the more difficult forming CTC. These results are explained with the relation between n-p conjugation and the twist angle.
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发布时间：2021-03-19
Research Bulletin
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