最新刊期
卷 ， 期 2 ， 1993
- 摘要：Wholly aromatic polyesters with different composition in main chain have been investigated by several methods such as hot-stage polarized light microscopy, X-ray diffraction, small angle laser scattering techniques, DSG, etc. The results showed that the melted copolyesters exhibit good liquid crystallinity in some range of the copolyester compositions, this report is focus on the relations of molecular composition-transitions-liquid crystallinity and morphologic features of mesophase.
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发布时间：2021-03-19 - 摘要：The structure of synthesized samples have been investigated systematically using IR,MS, NMR and element analytical instruments. In light of the analytical results the synthesized samples were proved to be hydroxy-propyl galactomannan, consisting with main structure of TQ powder. The degree of substitution of HT were determined by means of 1H-NMR.
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发布时间：2021-03-19 - 摘要：The reddish brown resinoid substance was separated out, when 1×10-4kg of FeCl36H2O was added slowly to 1×10-4m3 of 5% PVA basic (pH>13) aqueous solution with stirring. Its composition and forming process was studied by XPS, IR and ESR, etc. It follows that the de-protonic reaction of hydroxide group for PVA had taken place in above solution, and the coordination group for deprotonic oxygen of PVA had produced more. These ligands interact with some Fe3+ of ferric hydroxide while the ferric hydroxide in new emergence is forming,causing the formation of Fe (III)-PVA coordination polymer-the composition of the reddish brown resinoid substance.
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发布时间：2021-03-19 - 摘要：The ethylene-propylene copolymers with various monomer ratio have been synthesized by using titanium catalyst. The composition, monomer sequence distribution, molecular weight and crystallinity for the copolymers were determined. The side group-SO2Cl was introduced to ethylene-propylene backbones through chlorosulfonation with SO2Cl2. Effects pf initiator and sulfuryl chloride agent on sulfonation in chlorosulfonated products were investigated. Structural analysis of the chlorosulfonated copolymer by 13C-NMR has shown that hydrogens on CH3 could be substituted by a -SO2CI group while those on CH2 substituted by either -SO2CI or -Cl group,but those on CH substituted by neither pendant groups.
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发布时间：2021-03-19 - 摘要：In this paper, the hydrophobic cellulose nitrate microporous composite membranes have been obtained by modification of hydrophilic cellulose nitrate microporous membranes by the use of plasma polymerization of octafluorocyclobutane. The obtained hydrophobic microporous composite membranes have been used in membrane distillation (MD) process. The effect of preparation condition of the membranes on their structure and performance has been investigated by SEM, X-ray microscopical analysis and XPS.
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发布时间：2021-03-19 - 摘要：The effects of cooling rate (R) with crystallizing and melting behaviours of nylon 1010 and the melting of its samples which were quenched from melt at room temperature(RT) and liquid N2 (LN) and then annealed have been studied by DSC．The crystalzing temperatures are linearly decreased with R increasingr．If the crystallizations are finished above Tg，the cry-stallinities (C) are the same．When the initial temperature of crystallization >181℃，the cry-stal produced have 3 melting peaks which are about the transformation and melting of ringed and nonringed spherulites．The crystal formed within 181℃ to Tg is without the melting peak of nonringed spherulites．Heating the samples formed below Tg，there is a process of cold cry-stallization before the mehing．RT sample without annealing produces 3 melting peaks．When the annealing temperature Ta≥180℃，the samples have 2 peaks and C∞Ta LN sample without annealing has only l melting peak．When Ta>160℃，the annealed samples have 2 pea- ks．Ta≤160℃．there are 3 peaks．The lowest peak temperatures and C are both proportinal to Ta．
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发布时间：2021-03-19 - 摘要：The chemiluminescence kinetic properties were studied in the different spectral regions during oxidation of polyethylene. It is shown that the chemiluminescence from oxidation of polyethylene belongs to both spectral regions in which there are three peak processes. The processes of the first and the third peak were observed in the 480-725nm region successively. The process of the second peak can only by observed in the 330-400nm region. All of the three processes were observed in the 400-480 nm region.Among the three processes,the first peak process is related to the degree of oxidation of the sample,and the second and the third peak processes correspond to autocatalytic oxidation reaction.
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发布时间：2021-03-19 - 摘要：The polymerization of methyl methacrylate(MMA) in the presence of N-hydroxyethyl-N-methyl-para-toluidine(HMT) initiated with organic peroxide, such as benzoyl peroxide (BPO), lauroyl peroxide(LPO), has been studied. It was found that HMT can increase the rate of polymerization Rp and decrease the overall activation energy of polymerization E,. The values of E0 reduced from 85.8 KJ/mol using BPO alone to 41.3 KJ/mol using BPO/HMT as initiator. The rate equations of MMA polymerization were determined as follows: Rp=K[BPO]0.48[HMT]0.48[MMA]1.02 Rp=K[LPO]0.47[HMT]0.46[MMA]0.98 It fits well to the equation of polymerization with redox initiation system. UV spectrum end group analysis of polymer obtained revealed the presenceof HMT moiety in the end group. Accordingly, the radicals derived from aromatic amine will initiate monomer to polymerize.
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发布时间：2021-03-19 - 摘要：X-ray diffraction line profiles of low density polyethylene (LDPE)/(ethylene-propylene-octene-1) copolymer(EPO) blends have been analyzed with variance range function method. Theories for determining the microparacrystallite size and the distortion parameter from single reflection have been described, and the values of these two parameters at (110) and (200) directions have been determined.
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发布时间：2021-03-19 - 摘要：When the blends containing PHB/PET liquid crystal copolyester and PET were annealed near 280癈, it was found that the melting point of the blends decreased with the annealing time. If the annealing time was kept constant, the higher annealing temperature resulted in lower melting point. However, the melting point of the pure PET which had the same annealing history was almost not changed. It was demonstrated by NMR that the melting point decrease of the blends during annealing process was due to the transesterification between PHB/PET and PET. Therefore,the extentof transesterification of the blends can be estimated ac-cording to the thermal-properties of the blends and the change of the PHB/PET sequence structure.
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发布时间：2021-03-19 - 摘要：The morphology of quenched poly(ethylene terephthalate) "PET" films crystallized by several kinds of organic solvents or it's saturated vapors axe studied by tre SEM, SALS and PLM. It has been shown that the spherulite ball like structure is formed only in the surface-layer, and the structure of fracture can be divided into three layers according to difference of morphology. Depth of diffusion (A) dependson the time of solvent treatment (t). The plot of h vs t1/2 is linear.
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发布时间：2021-03-19 - 摘要：The solution properties for Poly(styrene-divinylbenzene) (PSt-DVB) in toluene and cyclo-hexane have been studied by photon correlation spectroscopy. The time correlation function of concentration fluctuation for PSt-DVB having wave vector q is proved to have the form of an exponential decay. The average decay rate is given by г= q2D. The variant rate of decay rate is zero within thhe accuracy errors. The first time correlation function of scattering field was analyzed by the method of cumulant. We obtained the diffusion coefficient of PSt-DVB particle as a function of theconcentration and tempera ure. The hydrodynamic radii for the particle in the good solvent,and the theta solvent,were calculated by means of Stokes-Einstein equa-tion. The molecular morphology for PSt-DVB particle in solution was also studied.
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发布时间：2021-03-19 -
STUDIES ON THE PREPARATION, STRUCTURE AND PROP- ERTIES OF AMIDOXIME GROUP CONTAINING CHELATING FIBER
摘要：One kind of amidoxime group containing chelating fiber with high adsorption．capacity to Au3+ ion (up to 626.7mg／g，when nitrile group conversion reaches 53.7％) was prepared by treating polyacrylonitrile fiber with hydroxylamine．The relationship between reaction condt-lions，fiber structure and properties was investigated．It is revealed that the decreases in tight-ness and regularity of PAN supermolecular structure are of advantage to raising nitrile group conversion．In the treatment process, the paracrystallite in the fiber begins to be fused at 70℃．The content of amidoxime group in the fiher increases at first then tends to steady value with the increase of hydroxylamine concentration lor reaction time，and does not increase quickly until reaction temperature reaches 70℃．The fiber strength decreases with the increase of reac-tion time，while does not decrease until the temperature is up to 70℃．It is suggested that，in order to prepare a chelating fiber with high amidoxime group content and reasonable mechani-cal property，the reaction should be immediately carried out slightly below 70℃．- 3
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发布时间：2021-03-19 - 摘要：The effect of AIR3 on the catalytical activity in Ziegler-Natta type polymerization of α-olefine with ASED-MO method was studied. Changes in energy and related activation energies in the process of chain growths with and without the presence of AlR3 were obtained. It ii shown that AlR3 enhances the activity of the catalyst remarkably. The function of AlR3 was discussed theoretically in terms of ASED-MO method.
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发布时间：2021-03-19 - 摘要：Crosslinked poly(methyl methacrylate) was first reacted with ethylenediamine or polyethy-lenepolyamine and then reacted with chloroacetic acid to form hydrophilic poly(methyl meth-acrylamide) resins containing α-amino acetic acid groups. The resins coordinated with Cu2+ were used as chromatographic supports to separate the neutral amino acids. The effect of the chromatographic conditions such as composition of the eluent, flow rate and column temperature on the separation was studied.
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发布时间：2021-03-19 - 摘要：The influences of molar ratio of reagent, reaction temperature, and reaction time on the synthesis of 1-(2-aminoethyl) pyrrolidine resin (AEPDR) have been studied. The functional group capacity of AEPDR is 2.74 mmol/g resin. The sorption capacities of AEPDR for Au (III), Os(IV), Pt(IV), Ir(IV), Ru(III), and Pd(II) are as high as 950, 520, 436, 418, 314, and 302 mg ion/g resin, respectively. The structure of AEPDR was confirmed by FT-IR and elementary analysis. The sorption rate curves and complex ratio were determined. The apparent sorption activation energies for Au(III) and Pt(IV) are △EAu=6.3 and △EPt=33.7 kJ/mol,respectively. The sorption mechanism has been nvestigated by XPS.
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发布时间：2021-03-19
Research Article
- 摘要：A novel functional monomer N-(2-Vinyloxyethyl)naphthalimide(VOENl) was synthesized and the photochemical behavior of its polymer was studied. With the electron-donating viny-loxyethyl group and the electron-accepting naphthalyl chromophore moiety coexisting in the same molecule, VOENI would form exciplex intermolecularly upon UV-irradiation and showed much lower fluorescence emission intensity compared with its polymer. Such a phenome-num was also termed as "Structural Self-Quenching Effect" similar to what had been reported previously in those structurally reversed cases of acrylinc monomers bearing oth electron-do-nating chromophore moiety and electron-accepting double bond in one molecule.
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发布时间：2021-03-19 - 摘要：Some acrylates having morpholino-moiety were synthesized and polymerized either in bulk or equeous solution by the initiation of AIBN or potassium persulfate. Studies on the change of transparency at various temperature revealed that, both Poly(morpholinoethyl methacrylate) P(MPEMA) and its slightly crosslinked hydrogel displayed remarkably thermosensitive character, and the thermo-sensitivity relied heavily upon temperature, pH value of medium and the degree of crosslinking. Such change of transparency was attributed to the microphase sepera-tion of polymersor hydrogels.
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发布时间：2021-03-19 - 摘要：β-Hydroxypropyl acrylate (HPA) and styrene (St) were copolymerized with ABIN as initiators. The reactivity ratios of the monomers were determined by several methods and the following data were obtained:γHPA-0.36, rSt = 0.45 (Mayo Lewis method); rHpA = 0-32, rst = 0.48 (FR method); rHPA = 0.34, rst = 0.46 (YBR method); rHpA = 0.33, rst = 0.48 (K-T method). Sequence distribution of HPA-St copolymer were also studied.
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发布时间：2021-03-19 - 摘要：The fluoresence behavior of N (2-methacryloyloxyethyl)-N-methy-p-toluidine (MEMT) monomer and its polymer has been investigated. It was observed that the monomer's fluoresence emission intensity was always lower than that of its polymer. This phenomenon was ascribed to the "structural self-queching effect". From the Stern-Volmer plots, the fluoresence quenching constant of PMEMT by different quenchers, i. e., methacrylonitrile (MAN), acrylo-nitrile (AN) fumadinitrile (FN), tetracyanoethene (TONE), methyl acrylate (MA), methyl methacrylate (MMA) were evaluated respectively. The more the electron-poor of monomers (quenchers) the higher values of fluoresence quenching constants were obtained. MEMT itself would photo-induced AN polymerization. In the presenceof benzophenone (BP) and under UV light irradiation,photo-induced graft copolymerization of AN onto PMEMT and P(ME-MT-co-MA) would take place. The grafted polymers obtained were characterized by FT-IR spectra.
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发布时间：2021-03-19 -
EFFECT OF MOLECULAR WEIGHT OF POLYETHYLENE GLYCOL ON CRYSTALLIZATION RATE OF FIBERFORMED COPOLYESTER
摘要：The effect of molecular weight of polyethylene glycol(PEG) on two kinds of copolysters was investgated. One is polyethylene terephthalate polyethylene glycol(PET-PEG) block copolyester, the other is - SO3Na group contained PET-PEG copolyester. It was shown that the higher the molecular weight of PEG the quicker the crystallization rate of copolyester. The result of difference in dyeability between copolyesters with PEG of different molecular weight was also obtained.- 2
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发布时间：2021-03-19
Research Bulletin
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