最新刊期
卷 ， 期 2 ， 1990
- 摘要：The graft copolymerization of acrylonitrile onto corn starch was investigated using manganic pyrophosphate [Mn(H2P2O7)3]3- as initiator. The effects of initiator concentration, monomer concentration, starch concentration and temperature on the grafting reaction have been examined. The results obtained are.1. In the range of [Mn3+] value from 2.0 to 2.5×10-3mol/L), the grafting reaction was dominantly terminated by polymer radical combinations, the polymerization rate is expressed as:From Arrhenius equation,with least square method Ko was calculated to be 3.37×102(L/mol·s)and activation energy E to be 25.90(kJ/mol).2. When [Mn3+]was increased to 3.0×10-3mol/L,Mn3+ion may terminate the grafting reaction and the rate equation is described as.
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发布时间：2021-03-19 - 摘要：The IR spectra of styrene-acrylic acid copolymer-supported neodymium complexes were investigated. The complexes possess a structure of bidentate carboxylate groups and the Nd-O bond in the complexes is rich in covalency. The general feature of the butadiene polymerization catalyzed by the supported neodymium complexes as well as the relationship between the nature, constitution of the complexes and the catalytic activity were studied. The copolymers prepared by solution polymerization in THF or dioxane were better supporter for the synthesis of highly active supported catalyst. The polymer-supported neodymium complexes containing about 12wt% functional group-COOH gave optimum catalytic actiity at Nd/-COOH molar ratio=0.20.
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发布时间：2021-03-19 - 摘要：The four new chelating resins of aminoisopropylmercaptan type with a polythioether backbone (PBM1, PBM2, PBM3, PBM4) were synthesized by the reaction between methylthiirane with various polyethylene polyamine resins (PB1, PB2, PB3, PB4) obtained from the treatment of polychloromethylthiirane with ethylenediamine, diethylenetriamine, triethylenetetramine and tetraethylenepentamine, respectively. These resirs exhibit high adsorption capacity and selectivity for noble metal ions. From an aqueous solution containing Au3+,Cr3+,Ni2+,Co2+,Cu2+,Mn2+,Zn2+,and Fe3+ only gold can be quantitatively adsorbed by the resin PBM4.
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发布时间：2021-03-19 - 摘要：Well-defined graft copolymers consisting of butyl acrylate (BA) homopolymer or hydroxyethyl methy acrylate and BA copolymer as backbone and polystyrene (PS) as side chains were synthesized by macromer technique to studied their application as a surface modifier for PS films. The results showed that the surface energies (rsD) of both sides of the PS film surface were changed appreciably by adding these graft copolymers but they gave rise to a constant beyond a scope of about 0.5wt% graft copolymer concentration and the differentcomponents of the graft copolymer used here could be enriched on both sides of PS film respectively,which have been iden-tified by ESCA and were consistent with the calculating results by the Gibbs absor-ption isotherm.
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发布时间：2021-03-19 - 摘要：The highly strong and conducting PA films were synthesized using ether-Ti (OBu)4-AlEt3 catalyst which was, treated by heating and using non-solvent polymerization method. The strength (over 102 MPa for tensile strength), stability and apparent density of PA film obtained in alkyl ethers (dibutyl and di-isopentyl ethers) are higher than that obtained in ring ethers (THF and dioxane), while the polymerization rate of the former is lower than that of the latter. Both PA films have the similar conductivities of 103S/cm and 104S/cm for stretched PA film. The results of SEM,TEM and IR spectra show that the fibre diameter and cis-PA content of PA films obtained by different ether solvents were quite different.
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发布时间：2021-03-19 -
STUDIES ON THE THERMAL DECOMPOSITION OF HYDROGEN PEROXIDE AND INITIATED ACRYLONITRILE POLYMERIZATION
摘要：The thermal decomposition of hydrogen peroxide in DMF and the polymerization of acry-lonitrile initiated by hydrogen peroxide were studied. The rate constants and activation energy of thermal decomposition of hydrogen peroxide in DMF were determined. And from the kinetic data measurments of the polymerization of acrylonitrile in DMF at 105℃, the polymerization rate equation of acrylonitrile was presented as Rp=K[H2O2]0.39[AN]1.85.- 2
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发布时间：2021-03-19 - 摘要：By using X-ray photoelectron spectroscopy (XPS), surface contact angle, surface potential and blood compatibility, the relationship between the composition and property of the surface and the blood compatibility of poly (ether-ester) multiblock copolymer and its blend has been studied. Experimental results indicated that the blood compatibility was very bad and bore no relation to the enrichment of PTMO soft segment in the surface phase for hydrophobic PET-PTMO multiblock copolymers. In the mixture of hydrophobic PET-PTMO and hydrophilic PET-PEO,and optimum blended proportion was found. The platelet adhering to the material surface conside-rably decreased at the optimum. △[C-O/[C
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发布时间：2021-03-19 - 摘要：Early stage of phase separation by spinodal decomposition in mixtuer of poly (methyl methacryate) (PMMA) and poly (styrene-co-acrylonitrile) (PSAN) was investigated with time-resolved light sacttering. The results indicate that the spinodal decomposition at early stage follows Cahn's linearized theory. The Maximum growth rate Rmax of phase separation has been revealed for the first time by time resolved light scattering. The theoretical R(q) is in agreement with the experimental one. Therefore, the interficial free energy can not been ignored in expression of R(q).
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发布时间：2021-03-19 - 摘要：Surface grafting of acrylic monomers onto High Strength Polyethylene (HSPE) fibre have been achieved by means of a photoinitiated continuous process, a UV lamp (320-440nm) used as a radiation source and benzophenone a photoinitiator. However it is difficult to measure such a thin layer of grafts by weighing usually used. The degree of surface grafts can be characterized by Electron Spectroscopy for Chemical Application (ESCA). The relative integral intensities of the ESCA core electron lines, oxygen and nitrogen to carbon,O1s/O1s and N1s/C1s,are used to indicate the relative degree of grafting of acrylic acid (AA) and acryla-mide (AM) as monomers,respectively. The determinations of the grafting by Fourier Transform infrared spectroscopy (FTIR) (ATR method) and "dyeability"as well as adhesion to epoxy resin for the grafted HSPE fi-bre are compared with those by ESCA,indicating that the relative integral intensity of ESCA core electron lines,RI%,can be appropriate to characterize relatively the degree of surface grafts of HSPE fiber.
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发布时间：2021-03-19 - 摘要：The morphology of irradiated high density polyethylene (HDPE) was observed with electron microscope and the relationship between morphology and radiation dose is analyzed quantitatively with statistical procedure.It has been found that the lamellar morphology of irradiated polyethylene did not change with changing radiation dose. If the HDPE samples irradiated at room temperature were melted and then recrystallized at 125±0.1℃ for 4 hours, the thickness of crystalline lamellae and the long period are reduced as compared with those without recrystallization. The results mentioned above are in good agreement with those obtained from SAXS exper-iments. They confirmed the "lamellar core damage mechanism" model.
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发布时间：2021-03-19 - 摘要：The copolymer of caprolactam (CL) and octamethyl cyclotetrasiloxane (D4) has been obtained successfully by ring-opening copolymerization under the same anionic catalytic condition, and characterized by H-NMR and IR spectra. When the monomer ratio D4: CL was 15 wt%, the percentage of monomer D4 entered into the copolymer chain may reach 76.3-83.5. The microph-ase separation of two components was observed by SEM. At appropriate proportion of monomer reactants, the copolymerized product had lower water sorption,lower coefficient of kine-tic friction,and higher impact strength than that of polycaprolactam.
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发布时间：2021-03-19 - 摘要：Terpolymerization of ethylene,propylene and 1-butene were carried out with TiCl4, Ti(OBu)4/MgCl2/ethylbenzoate/ 2SiCl2/AlEt3 catalyst which was developed in this laboratory. The influences of various conditions such as monomer composition, temperature, triethylaluminum concentration and catalyst concentration on the catalytic efficiency, decay of polymerization rate and the inh value of resulting products were studied in detail. It was found that the catalytic efficiency was much higher than that of the homopolymerization of the three monomers,i.e. 8.6×104g terpolymer/g-Ti in one hour under the optimum conditions. The decay of polymerization rate with time fulfills the equation:Rt=Rs+(Ro-Rs)e-βt.
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发布时间：2021-03-19 - 摘要：The characterization of ethylene-propylene-1-butene terpolymers synthesized by TiCl4, Ti (OBu)4/MgCl2/ethylbenzoate/2SiCl2/AlEt3 catalyst is described. DSC, WAXD analysis and solvent extraction show that the EPB terpolymers in a certain range of composition are elastomers without detectable crystallinity, which demonstrates a rather random structure and makes them promising for quality rubber. The comonomer sequence distributions are, by 13C-NMR analysis of binary copolymers, first-order Markovian for EP and EB copolymers but Bernoul-lian for PB copolymer. Three pairs of monomer reactivity ratios were evaluated. The assign-memts of the chemical shifts in the 13C-NMR spectra of EPB terpolymer was made and a method was proposed to determine the chemical composition of the EPB terpolymers.
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发布时间：2021-03-19 - 摘要：The Kinetics of polymerization of acrylamide (AAM) initiated by eerie ion-alkyl phenylcarbamate and eerie ion-alkyl 4-methylphenylcarbamate redox systems in the temperature rang of 20-40℃ has been investigated. It was found that eeric ion coupled with alkyl 4-methylphenylcarbamate was a very effective initiating system for the polymerization of AAM. The overall activation energy of polymerization and the rate equations of polymerization were determined. A initiation mechanism involving the formation of a complex between Ce4+ and alkyl phenylcarbamate whose decomposition yields the initiating free radical has been sugested.
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发布时间：2021-03-19 - 摘要：In the present paper a new type of polyether polyester block copolymer (MPEE) consisting of two components of polyethers (PTMG and PEG) as soft segment component has been synthesized. And it has been also investigated in comparison with blended polyether polyester block copolymer (BPEE) consisting of the same composition ratio of hard and soft segments and both two polyethers (PTMG and PEG), It was found that: (1) Improvement of blood compatibility of polyether polyester block copolymer can be achieved by in-troducing hydrophilic component PEG into it; (2) Generally the blood compatibility of MPEE type is better than that of BPEE; (3) Under a specific molar ratio of PTMGT-PET to PEGT-PET (60/40) the blended copolymer (BPEE 60/40) shows the best blood compatibility,as well as mechanical property. This might be related to more tiny microphaseseparted structure. The relationship between blood compatibility and structure of copolymer has been discussed.
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发布时间：2021-03-19
Research Article
- 摘要：Referring to C. N. Nicholas and C. Booth's method, modified polyoxyethylene electrolyte was prepared from polyethylene glycol and dichloromethane. The molecular weight MPK of the obtained polymer was measured by GPC that was greater than 105. The chain structure was characterized by C13NMR which indicated that the polymer was oxymethylene-linked polyoxyethylene. The DSC results of the sample showed that the glass transition temperature Tg~-60℃. the melting point Tm= 11℃,the crystallinity at -20℃ was Xc=26%. The sample appeared as elastomer at room temperature. Whenit was dopped with LiCF3SO3 and made into a film,its conductivity at room temperature was measured by method of AC Impedence, that was δ=6×10-5(Ωcm)-1.
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发布时间：2021-03-19 - 摘要：The inhibiting effects of N,N'-diethydroxylamine(DEHA), N,N'-diisopropylhydroxylamine (DIPHA), 2,2,6,6-tetramethyl-4-hydroxyl-piperidinhydroxylarnine (TMHPHA), 4-hydroxyl-morpholine(MPHA), N-phenylhydroxylamine(PHA) and N, N'-diphenylhydroxylamine (DPHA), on the AIBN-initiated, bulk polymerization of styrene(St) have been studied by dilatomatric method. The inductive period of polymerization(ti), the rate of propagating after the ti(Rp), the MW of polystyrene (Mn) the retardating coefficient (K) and the inhibi-ting factor (F) have been obtained. The results reveal that R2NOH have been proved to be very efficient inhibitors and their inhibiting efficiency have been found to depend on the rate and stability of the nitroxide radical formed in reaction. Relative inhibiting reactiveties of several R2NOH have been determined as in the following order; DEHA>TMHPHA>DPHA>DIPHA>MPHA. Other stable nitroxides formed in polymerization of St inthe pre-sence of several R2NOH have also been indentified by ESR and mechanism of inhibition and retardation has been discussed.
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发布时间：2021-03-19 - 摘要：The effects of the addition of 2.38×10-2 to 2.86×10-2 M AIBN and 8.8×10-2 to 6.1×10-4 M six substituted hydroxylamines, such as, N,N-diethlhydroxylamine (DEHA), N,N'-diisopro-pylhydroxylamine (DIPHA), N-hydroxyl-mofpholine ; (MPHA), 2,2,6,6-tetramethyl-4-hydro xyl-piperidinehydroxylamine (TMHPHA), N-phenylhydroxylamine (PHA) and N,N'-diph-enylhydroxyamine (DPHA) at 60℃ on the bulk polymerization of vinyl acetate (VAC) and .acrylonitrile (AN) has been studied respectively. The results showed that all six hydroxyla-mines exhibited inhibiting properties. The effect is more pronounced for VAC than for AN. At the sametime the chain transfer constants (Cs) of these compounds in bulk polymerization of VAC and AN has been calculated respectively by Mayo equation. The result demonstrated that the Cs value for VAC in bulk polymerization is larger than that of AN under same condition. These differences not only depend on the structure of six hydroxylamines and the nitroxide ra-dical derved from them in reaction,but also on the electron-donating or electronaccepting pro-perties of monomers used and radicals formed.
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发布时间：2021-03-19 - 摘要：Inflences of temperature and composition on the curing mechanism and the glass transition temperature (Tg) of the cured compound in benzyldimethylamine (BDMA) catalyzed-dicyan-diamide (DICY)-epoxy resins (DGEBA) system was studied by IR, DSC, dielectric and dynamic mechanical properties. The results indicated that the curing involved the addition reaction of amino groups with epoxy groups, besides the etherification of epoxy groups. The etherifica-tion as a competitive reaction was not favor both at 100℃ and 170℃.In addition,at 140℃ or 170℃,the reaction of cyano groups with hydroxy groups aor epoxy groups gave rise to im-ino-ether bond,which then rearranged to the compound of acylamide bond. A higher Tg of cu-red compound network could be reached with a amine-to-epoxy ratio(a/e) of 0.6 in the same cured condition.
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发布时间：2021-03-19 - 摘要：The photopolymerization of acrylonitrile (AN) was studied by using 8-acryloyloxyquino-line (AQ) and its polymer (PAQ) as sensitizers under UV irradiation. The photopolymerization rate of AN in DMF by using AQ as sensitizer is proportional to 0.36th power of AQ concentration and 1.10th power of AN concentration. In the case of PAQ as sensitizer for the photopolymerization of AN, the rate is proportional to 0.31th power of PAQ concentration and 0.73 th power of AN concentration. From the recording of fluorescence intensity of PAN sensitized by AQ and PAQ,it is confirmed that AQ and PAQ not only sensitized the photopolymerization of AN but also entered into the PAN chains. The initiation mechanism was tantatively deduced.
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发布时间：2021-03-19 - 摘要：A new series of Interpenetrating polymer networks (IPN) was prepared by using both free radical and cationic photoinitiators simultaneously under ultraviolet radiation. The systems studied were castor oil based ure'thane acrylates (Network I) and epoxy resin (Network II) (UV-IPN). In order to compare the effect of different crosslinking operations, urethane-acrylate/ amine cured epoxy resin (AC-IPN) and urethane-acrylate/epoxy-acrylate conetwork (EA-CPN) systems were also synthesized and their dynamic mechanical and stress-strain properties were examined. The results show that UV-IPN exhibits only one Tan δ peak,while two Tan δ peaks can be seen in AC-IPN systems. This suggests that the former is much more compatible than the later.The stress at break was found to increase as epoxy resincomponent increased in both UV-IPN and AC-IPN,while appeared to decrease in EA-CPN as epoxy-acrylate increased.
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发布时间：2021-03-19
Research Bulletin
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