最新刊期
卷 ， 期 6 ， 1992
- 摘要：Flourimetric emission spectra of monomer and excimer in aqueous solution of sodium poly (styrenesulfonate), with or without added salt has been expermentally measured py fluorescent spectrophotometry. It shows that the ratios (IE/IM) between excimer and monomer emission intansity varies with the kind, concentration and vaiens of added salt. At the same salt concentration the order of IE/IM systems can be described as: KCl > NaCl≥LiCl and CaCl≥MgCl.Also, the fluorescence quenching of molecule of polyelectrolyty ibn aqueous NaCl were-studied. Resuts shows that as the concentration of added salt increase gradually,the polyelec-troyte molecule will turn from rod-like state into random string ball state which makes the for-ming of excimer easily.
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发布时间：2021-03-19 - 摘要：The quotient of swelling ratio of homogeneous network in good solvent Q to that in poor solvent Qv satisfy the relationship Q/Q0 = 1+k(Q-1) in which k is a constant depending on the structure of the solvent and the monomer units of the network. If the constant k is pre-determined, the heteregeneity factor Z of the inhomogeneous real networks could be evaluated fromZ = k(Q -1)(Q0-1)/[(1-k)(Q-1)-(Q0 - 1)]The proposed method was sucessfully applied o the characterization of the inhomogeneous network of divinylbenzene-styrene random copo ymer initiated by free radicals. The variationof the estimated structural parameters are in accord with the prediction made from the me-chanism of random copolymerization and network formation.
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发布时间：2021-03-19 - 摘要：The phase separation and the effect of composition on phase inversion, phase structure and dynamic mechanical properties of PMMA/PEA LIPN have been investigated. A comparison of the structure and damping properties between LIPN and mixture system has also been done. The results suggest that the segregation degree of components is lower and the density is higher in LIPN than that in mixture system due to the interpenetration of one network into the other. A refined structure is revealed in LIPN, but not in mixture system. At low EA content the PEA with cell structure dispersed in the PMMA continuous phase,while as EA content continuously increases,the phase inversion will occur and over the range of EA volu-me fraction from 48% to 86% the PMMA and PEA both form co-cotinuous phase where se-veral properties change very rapidly,the higher damping property appears. The calculated curve by using a combination of upper and lower bounds of Halpin-Tsai-Nielsen equation and logarithmic rule of mixtures fits the eperimental data very well.
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发布时间：2021-03-19 - 摘要：In this paper, we discuss the effect of spherical micelle on the crystallization behaviour in dilute poly (methyl methacrylate-b-tetrahydrofuran) diblock copolymer/tetrahydrofuran ho-mopolymer solutions. The results show that even for very small copolymer volume fractions, micelles may restrict the nucleation of polytetrahydrofuran obviously for which a good explanation can be made according to the micelle theories developed by Leibler, Orland and Wheeler and by Whitmore and Noolandi.
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发布时间：2021-03-19 - 摘要：Studies on two series of segmented polyester polyurethaneurea (PUU) elastomers based on 4,4-diphenylmethane diisocyanate(MDI), ethylene diamine(ED) and polybutylene adipate (PBA)(M. W. 1975 and M. W. 1228) were made by DSC. Further, thermal changes of soft segment crystalline of these materials at different annealing conditions were also investigated. The results showed that in both series, PBA 1975 series had a lower T, of soft segment phase than PBA 1228 series, indicating that the phase segregation of the former was better,Both the soft segment Tgs and the hard segment Tgh were not sensitive to the changes of the hard segment contents in the samples. The results on the annealed samples showed that soft segment crystal-line melting existed in two peaks. The hypothesis of the existence of two types of crystallines (P2 and Ph) in the soft segment phase was proposed,and the reason that these two types of crystallines formed was analyzed theoretically.
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发布时间：2021-03-19 - 摘要：The crystallization kinetics in mixtures of poly (ε-caprolactone) (PCL) and poly(styrene-co-acrylonitrile)(SAN) has been investigated as a function of composition and crystallization temperature. The isothermal growth rates of PCL spherulites decrease with increasing concentration of SAN. The radial growth rates of the spherulites were described by the kinetic equation including the interaction parameter, because of miscible mixtures of PCL/SAN. The interaction parameter obtained from the fitting of kinetic equation with experimental data is in good agreement with that obtained from melting point depression method. The folding sur-face free energies σe decrease with the increase of SAN content. In light of these results,it is suggested that,for these mixtures,the noncrystallizable polymer SAN reduces the mobillty of crystallizable polymer PCL.
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发布时间：2021-03-19 - 摘要：Rheological behavior and thermostability of aqueous solution of carboxymethyl hydroxy-propyl cellulose ether(CMHPC) in the temperature range from 25 to 80℃ were studied by rotatory viscometer. The energy of ac'ivation of viscous flow, related with Arrhenius equation is between those of HEC and PAC. The research results showed that CMHPC was similar to PAC at higher CM content and corresponded to Ostwad-Der Waele model perfectly. A higher HP content the flow curve didn't follow the model. After adding small molecule electro-lytes into CMHPC aqueous solution COO-ions were shielded by counter ions. Thus the hydro-xypropyl group became major effect and influenced the rheological behavior.The salt tole-rance of CMHPC in solutions was also studied with different type of ions and concentration.
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发布时间：2021-03-19 - 摘要：Chelate compound di(isopropyl phthalate-oyloxyl)-acryloyloxyl aluminium(DIAA) and its polymer were synthesized. Their structure were characterized by elemental analysis, VPO, MS, IR, 1H-NMR and 27Al-NMR. Their hydnlytic stability in the air, heat-stability and fluorescent property in solution were reported.
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发布时间：2021-03-19 - 摘要：This work investigates the influence of the chemical composition and molecular weipht distribution on heatresistant and physical properties for methyl methacrylate-styrene-N-phenyl-maleimide terpolymer generated by free radical terpolymerization. The experimental results indicate that under the given conditions, a proper mole ratio among the monomer mixture will possibly give rise to a terpolymer with comprehensive physical properties.
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发布时间：2021-03-19 - 摘要：A series of poly(ethvlene terephfhalate) (PET) films with different degrees of planar orien-tation [△(xy)z] , crystallinity and molecular weight were obtained by biaxial stretching, annealing and γ-irradiation on respectively. In oriented PET electrets, the mean depth of trap level was increased with increasing of △(xy)z and the ability to trap charge carriers was raised in the structural traps formed from orientation. 60Co γ-iiradiation of a large dose (0.5-5 MGy) led to the breaking of macromolecular chain and the increasing of group density of benzyl with oxygen. Though the mean depth of trap level was deepened,the ability of detrapp-ing change carriers was increased for γ-irradiated PET electrets. Crystallization by annealing made the depth of trap level deep too,but the ability to trap charge carriers showed a maximum at crystallinity of 20%. The three kinds of trap models were proposed corresponing to the three methods of sample treatment on the basis of the depth of trap level,the current maximum of detrapping charge carriers and the initial density of charge carriers.
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发布时间：2021-03-19 - 摘要：A handy, reliable and efficient etching method used to characterize the morphology of nylon-6, i.e. CCl3COOH solution, was established. It was the first time that the crystal morphology of monomer casting nylon-6 and its modified samples was directly observed by means of SEM. Their spherulites of tens micron were three-dimensionally clear. The crystalline structure of modified MC nylons can be successfully studied by means of the physical or chemical effect of CCl3COOH and its solvent on the modifying agents.
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发布时间：2021-03-19 - 摘要：In this paper the aromatic-aliphatic copolyamides were synthesized from terep-hthalyl chloride (TPC), p-phenyldiamine (PPD) and aliphatic diamines (ADA. H2N-(CH2-)nNH2, n=2,6,8,10, 12) by low temperature solution polycondensation. The effects of the amount of the aliphatic diamine chain unit in copolyamides, inherent viscosity of copolyamides and temperature on the critical concentration of liquid crystalline copolyamides obtained were studied. It was confirmed that the sulfuric acid solution of these copolyamides was smectic if the aliphatic diamine unit in copolyamides was more than 16.7 mol%.
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发布时间：2021-03-19 - 摘要：Michael addition reaction between poly (vinyl alcohol) (PVA) and propyl vinyl sulfoxide (PrVSO) was studied in sodium hydroxide aqueous solution. The functional polymer with various sulfoxide contents were synthesized and characterized by means of IR, 1H-NMR, X-ray diffraction and thermal analysis, etc. The results showed that crystallinity of the functional polymer decreased with increasing content of sulfoxide group in the polymer, and its solubility in cold water, dimethylsulfoxide, methanol, ethanol and dichloromethane was enhanced.
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发布时间：2021-03-19
Research Article
- 摘要：A novel acrylic monomer bearing pyrimidino-moiety, N-methacrylyl-N'-pyrimidinopipe-razine (MPMP) was synthesized by the reaction of N-pyrimidinopiperazine and methacrylyl chloride in the presence of triethylamine. Both absorption and fluorescence spectum for the monomer and its polymer were recorded. It was observed that the fluorescence intensity of monomeric MPMP was slightly lower than that of its polymer. The monomer did not dramatically appear its structural self-quenching effect as we have reported previously. The fluores-cence of the polymer,P(MPMP) culd be quenched by electron-deficient quenchers such as methacrylonitrile,acrylonitrile,fumaronitrile; methyl acrylate and methyl methacrylate. The Stern-Volmer constants of those quenchers for P(MPMP) were determined.
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发布时间：2021-03-19 - 摘要：Most of bioactive species such as enzyme and antibody will be damaged and lose part of their bioactivity when they are irradiated by ionizing radiation at room temperature. Low temperature could somewhat control the effect, so kaetsu and his co-workers developed an entrapping technique at low temperature ( - 78℃). On the other hand, some enzymes such as catalase and house radish peroxidase have so-called radiation-induced post-deactivation effect as well. In order to avoid the trouble in performance and loss of bioactivity, a physical ent-rapping of bioactive species via preirradiation polymerization at room temperature were deve-loped in the Authors'lab. In this work we developed this technique. The glucose oxidase was entrapped in polyacrylamide hydrogel ind uced by pre-irradiation. Experiments under several different conditions such as absorbed dose and concentrations of enzymes,monomer and crosslinking agent were carried out. The results showed that this technique can be used ex-tensively in various enzyme.
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发布时间：2021-03-19 - 摘要：The effects of polymer/filler interaction on the mechanical properties and rheological properties of kaolin filled polyamide 6 composites have been studied by calculating the surface energy and its components of kaolin and polyamide 6 matrix, the equilibrium work of adhesion and interfacial tension between kaolin and polyamide 6. The results show that the mechanical properties and rheological properties of kaolin/polyamide 6 system are determined not only by equilibrium work of adhesion and interfacial tension, but also by chemical reaction between kaolin and polyamide 6.
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发布时间：2021-03-19 - 摘要：An evidence has been found by 1H and 13C NMR techniques for the presence of structural isomerism of side chain in liquid crystalline polysiloxane due to α- and β-additions of alke-ne monomers. A liquid crystalline polysiloxane from poly (methylhydrosiloxane) and 4-(al-lyloxy) benzoyl-4-methoxyphenyl contains as many as 42% α-addition isomeric side chains based on our NMR data. It is thus pointed out that the strength change of Si-H absorption band in IR or NMR spectra can only reflect the extent of completion of hydrosilation,it does not necessarily mean the liquid crystalline polysiloxane produced contains β-addition iso-meric side chains only.
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发布时间：2021-03-19 - 摘要：The irascibility of a poly (ether imide)/phenolphthalein poly (ether ether ketone) blend was determined by viscometry. The results ob ained indicate that the Huggins coefficients of the blends exhibit positive deviation from simple additivity, while the inherent viscosities of the blends exhibit negative deviation. The a values of viscometry, calculated from these parameters are all >0. It is obvious that the blends are miscible within the whole composition range.
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发布时间：2021-03-19 - 摘要：A novel acrylic monomer having acridonechromophore, 2-(N-acridonono)ethyl methacry-late (AEMA) was prepared from methacryloyl chloride and N-hydroxyethyl acridone (HEA), which was obtained by reaction of acridone with ethylene carbonate. Both the monomer and its polymer can initiate the photopolymerization of vinyl monomers, such as AN, MMA etc, but P(AEMA) has higher initiation ability than monomeric AEMA does. The effects of oxygen and aliphatic tertiary amine on the polymerization rate were also revealed. The UV-analysis indicates that AEMA not only initiates photopolymerization of vinyl monomers,but also enters into the polymer chains.
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发布时间：2021-03-19
Research Bulletin
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