最新刊期
卷 24 ， 期 6 ， 2011
- 摘要：This article review show polymer science in China opened to the world during the past 30 years of reform and opening-up. Analysis and discussions are made on three main aspects: the rise of publications in international journals; the developments in organizing international symposia from small bilateral ones to IUPAC World Polymer Congress and the role of sending visiting scholars and students to abroad.关键词：Polymer science;Reform and opening-up;Polymer publications;International symposia;Sending visiting scholars to abroad
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发布时间：2022-09-18 - 摘要：Block copolymer (bcp) templates have been intensively studied to fabricate a variety of nanostructures.Creating nanocellular and porous polymeric materials using bcp templates is a branch of objectives of the bcp template techniques.Conventional methodologies to fabricate porous polymeric materials are based on decomposition of particular bcp domains using ozone,biodegradation,and ultraviolet light.In this review,we report a novel,environmentally benign method using CO2 to fabricate nanocellular polymeric materials using a fluorinated bcp as the template.关键词：Supercritical fluids;Block copolymers;Microphase separation;Nanoporous materials
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发布时间：2022-09-18 - 摘要：The microfibers generated in immiscible polymer blends can usually improve the mechanical properties of blends significantly.This paper reviews the formation mechanism and stability of microfibrillar morphology in immiscible polymer blends.The influence of material properties and processing parameters,such as viscosity ratio,capillary number,flow properties,coalescence,elasticity, crystallization,confined condition,on the microfibrillar morphology are discussed.关键词：Microfibrillar;Immiscible polymer blends;Stability;Deformation;Formation mechanism
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发布时间：2022-09-18 - 摘要：5-fluorouracil is one of the most widely used cytotoxic antitumor agents.It has been used in the carcinomas of colon,breast,gastrointestinal tract and liver.But its activity is also accompanied by strong side effects that had greatly limited its clinical applications.Polymeric prodrugs of5-fluorouracil can reduce its toxicity,increase duration of antitumor activity and additionally,an affinity for tumor cells.In this review the research on polymeric prodrug of 5-fluorouracil and their targeting antitumor activities were reported.关键词：5-Fluorouracil;Polymer;Prodrug;Targeting drug delivery
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发布时间：2022-09-18 - 摘要：Cellulose is the most abundant renew able resources. Cellulose is insoluble and refractory because of hydrogen bonds, consequently, the molding process is relatively difficult. Electrospinning is a processing technology to prepare polymer ultrafine fibers by driven polymer solution or melt flying in the electrostatic field through the jet. Micron- or nano-fibers of cellulose and its derivatives fabricated by electrostatic spinning hold unique functions and wide application prospects. This paper briefly described the principle of electrospinning and research background, summarized the progress of research work of researchers in recent years, made a brief summary of elect ro spinning cellulose solvent system, focused on preparation methods and applications of cellulose and cellulose derivatives fibers with different shapes and different functions.关键词：Cellulose and its derivatives;Electrospinning;Shapes and functions;Applications
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发布时间：2022-09-18 - 摘要：The effects of thermal ageing of rubber on its stability, structure and mechanical properties are summarized. The methods of prediction the service life of rubber are introduced. Relative suggestions are given through analyzing the research results.关键词：Rubber;Thermal ageing;Suggestion
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发布时间：2022-09-18 - 摘要：In the paper,the main methods and results of the hemicellulose structure study are viewed.The advantages and disadvantages of each method are compared.The application of the methylation method,periodate oxidation,fourier transform infrared technique (FTIR) ,nuclear magnetic resonance (NMR) and atomic force microscopy (AFM) in structure analysis are presented.The studies of hemicellulose structure are summarized,including summary structure and advanced structure.Several important hemicellulose modified products and their applications are also introduced.关键词：Hemicellulose;Primary structure;Advanced structure;Modification
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发布时间：2022-09-18 - 摘要：Covalently cross-linking is a feasible and effective method to modify proton exchange membranes,which can not only suppress water swelling and methanol permeability but also enhance mechanical properties and chemical stability of membranes.The methods of covalent cross-linking and the properties of cross-linked membranes are discussed in details.The latest development of covalently cross-linked proton exchange membranes is also reviewed.关键词：Covalently Cross-linking;Proton exchange membranes;Direct Methanol Fuel Cells
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发布时间：2022-09-18 - 摘要：We studied the mechanical properties of ethylene vinyl acetate toughened PLA/TPS,the influences of nano-CaCO3 on the shrinkage,thermal stability of the composite.The results show that EVA toughened system have good toughness,nano-CaCO3 improved the shrinkage and thermal stability of the composite materials.关键词：PLA;Thermoplastic starch;Ethylene vinyl acetate;CaCO3;Toughening shrinkage;Thermal stability
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发布时间：2022-09-18 - 摘要：Marble powder was modified by stearic acid coupling agent after marble scraps were grinded. Natural rubber/marble powder composites were prepared by direct blending technology.The results showed that the average particle size of marble powder was 24.18μm.The best mechanical properties of composites were obtained after modified marble powder content were 10 percent in the natural rubber,and the tensile strength was 20.11Mpa.The heat resistance of composites was higher than unmodified marble powder/NR composites. Activated marble powder has excellent reinforcement effect and ideal processing characteristics,and can replace carbon black in rubber to achieve its application.关键词：Marble stone powder;Natural rubber;Tensile property;Thermal stability
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发布时间：2022-09-18 - 摘要：HDPE/ nano-magnesium hydroxide ( MH ) surface modified in solvent / microencapsulized red phosphorus ( MRP ) non-halogen flame-retarded composites was prepared by meltblending.The influence of the ratio of material,surface modification on properties of composites was studied.The results showed: the surface modification for MH in solvent makes the modifiers adhere to the surface of MH,the particles size increase slightly.The pictures taken by SEM shows that the surface modification is propitious to the dispersing of flame retardant in resin.Adding MRP to MH bring synergistic effect in improving the flame retardancy,the influence on mechanical properties is unconspicuous.When the ratio of HDPE/MH/MRP is 100/50/7.5,the composites own good flameretardant and mechanical properties.关键词：HDPE;Nano-magnesium hydroxide;Microencapsulized red phosphorus;Surface modification;Flame retardancy
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发布时间：2022-09-18 - 摘要：Due to the strong o xidizing ability, supernormal-valence transitionmetal cations could form redox initiat ing systems with various reducing agents for the radical polymerization. This review covers (1) the electronic config uration and complex structure of commonly used superno rmal-valence transition metal cations; (2) the redox initiatiation mechanism of supernormal-valence transition metal cations with amides and alcohols; (3)the tailor-made synthesis of graft, block, hyperbranched and star-shaped polymers based on the supernormal-valence transition metal cations-catalyzed redox initiation.关键词：Supernormal-valence transition metals;Redox initiation;Radical polymerization
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发布时间：2022-09-18 - 摘要：Catalytic properties of carbon nanotubes are int roduced and the application of CNTs supported metal (M/CN Ts)in the field of hydrogenation cataly sticreactions within recent several years was reviewed. And the develo pment oriention of M/CNTs in the future is also pointed out.关键词：CNTs;Catalyst;Hydrogenation reaction
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发布时间：2022-09-18 - 摘要：The property and function of a polymer was significantly influenced by their stereoregularity. Lewis acids were widely applied in stereocontrol radical polymerization because of their unique reactivities and selectivities,as well as mild reaction conditions.Among the many Lewis acids,rare earth metal,such as Y, Sc,Yb,La,Pr,Lu,Tm,trifluoromethanesulfonates were particularly effective in increasing the isotacticity of various polymethacrylates and poly (meth) acrylamides.In this paper,the application of Lewis acids as catalyst in radical polymerization was introduced,and the progress in stereospecific radical polymerization of methacrylates and (meth) acrylamides catalyzed by rare earth metal trifluoromethanesulfonates was emphatically reviewed.关键词：Lewis acid;Rare earth metal;Trifluoromethanesulfonate;Radical polymerization;Tacticity
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发布时间：2022-09-18 - 摘要：Probability effect is one of the most important factors that influence the chemical reactions of polymers.A case in point is the dechlorination of polyvinyl chloride (PVC) when heated with zinc.Under the assumption that the probability of reaction of each adjacent pair of unreacted substituents is the same,Flory predicted that the theoretic value of the maximum extent of this reaction was86.47% (or1- e-2 ) via recursion method.In this article,under a different assumption that each unreacted substituent reacts with its adjacent substituent on either side with equal possibility,the reaction of one polymer chain was modeled by computer programming.The result indicated that the maximum extent of this reaction was86.06%. In the meanwhile,taking advantage of the fact that the instructions in the program were related to the intramolecular rotation of each freely rotating unit in the polymer chain,the procedure of this reaction was predicted and discussed and the kinetic plot which was in agreement with experiment result was obtained.关键词：Chemical reactions of polymers;Probability effect;Computer Modeling
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发布时间：2022-09-18 - 摘要：Biopolymer,biodegradable polymer and bio-based polymer are important terms about environmental friendly plastics.They are both correlative and distinct.In this paper,the meaning of these terms was clarified.For biopolymer,it must be derived from renewable resource and produced by biotechnology; For biodegradable polymer,it could be made from either bio-based or petroleum-based materials.But for the bio-based polymer is concerned,we only focus on whether it is made from renewable materials or not.It could be biodegradable or non-biodegradable.关键词：Biopolymer;Biodegradable polymer;Bio-based polymer;Environmental friendly plastics
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发布时间：2022-09-18 - 摘要：Learning of equations of polymerization degree is very important in condensation polymerization.However,it is usually difficult for students learning how to use these equations to calculate polymerization degree.To solve this problem,the scope of application of the five equations of polymerization degree was discussed,and how to select proper equation of polymerization degree was illustrated by examples in this article.关键词：Polymer chemistry;Condensation polymerization;Equations of polymerization degree
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发布时间：2022-09-18 - 摘要：Combining of the teaching practice of our own,it has incorporated the ideas of science, economy and environmental protection into the experiment teaching to satisfy a need of the tree experiments teaching reformation of basic experimental system of polymer materials and engineering major.The unitary optimization and reformation of fundamental experimental system of the major content,organization,operation,teaching methods and means were explored,and the education effect of polymeric experiment was raised evidently,meanwhile,the cost,pollutants of experiments were reduced significantly.The maximization of benefits of the fundamental experiments of polymer science teaching comes true.关键词：The fundamental experiments of polymer science;Optimization;Reformation
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发布时间：2022-09-18
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