摘要:Carbon dioxide is an ideal synthetic feedstock for its non-flammability,relative non-toxicity,inexpensiveness, and abundance in nature. Also,aliphatic polycarbonates made from CO2 and epoxides are biodegradable polymeric materials. Therefore,much attention has been paid to the copolymerization of carbon dioxide with epoxides to produce aliphatic polycarbonate. A significant amount of research has been directed toward the development of catalysts with improved activity and selectivity. The present paper gives an overview on the recent progress in the research of catalysts for such a copolymerization process.
摘要:In this paper are reviewed the researches of copolyanhydrides, including their preparation, structure and properties, pharmecautical artwork, applications in sustained and controlled release system .The future applications of these copolymer materials are also prospected.
摘要:In this paper,the synthesis methods,particular photo-electronic properties,and characterization of unsymmetrical phthalocyanines were briefly introduced. Their recent studies in organic non-linear optics,molecular rectifiers,and gas-sensitive sensor were reviewed. Several effective suggestions to synthesis of unsymmetrical phthalocyanines were presented as well.
摘要:As drug release carriers,chitosan has played an important role in the less administration frequency, low toxicity,and cure efficiency enhancement. In this article,the recent progress in the preparation and properties of chitosan-based release carriers has been reviewed,including nanoparticle,microsphere,tablet,film,and gel. Furthermore, their advance in the future was also introduced briefly.
摘要:The oxidative polymerizationmethods of aromatic polyfuran are summarized in this review .The influence of several vital polymerization conditions on the properties of the polyfuran is discussed systematically .Chain structure of polyfuran is deduced .Several improvement methods and effects on the polyfuran are introduced .It is pointed out that the polyfuran and its copolymer are organic semi conductors with a widely variable conductivity from 10-11 to 10-1 S·cm-1.The polymer films deposited by an electrochemically oxidative polymerization exhibit unique electrical activity, excellent thermo forming ability and special surface morphology .The polyfuran could be potentially used in adsorption, enrichment and sensor for the metal or organic materials .
关键词:Polyfuran;Conducting polymer;Electrically active polymer
摘要:Ionic liquids are organic salts that are liquid at ambient temperature .They have attracted much attention in both academia and industry as nonvolatile, recyclable media for a wide range of chemical processes including extraction, electro-chemistry and organic reaction .As a reaction media, their ion structure, high polar and viscosity properties have leaded to significant improvements in rate and yield in many polymerizations .These also have a influence in molecular weight and polymer structure .In this work, the free radical polymerization and the atom transfer radical polymerization ( ATRP) in which ionic liquids were used as solvents are discussed mainly on the basis of the kinetics, mechanism and the polymer structure as well as the recycle of the ionic liquids according to the results published in recent years .
摘要:The formation and characterization of the interphase in multi-phase polymers were summarized in this paper. The interphase characteristics and their influences on properties of multi-phase polymers were reviewed as well. Emphasis was placed on discussing the effects of different compatibilizers on the interphase behavior. The influences of molecular weight and concentration of block copolymer based compatibilizers on the interphase behavior have been extensively investigated and quantitative relationships have been made. However,few investigations have been made on the effects of compatibilizers based on graft and random copolymers on the interphase behavior. It is anticipated that a quantitative correlation among interfacial tension,interphase thickness,and properties,particularly mechanical ones,of multi-phase polymers is a promising aspect in the field of polymer physics.
摘要:Frontal polymerization is a mode of converting monomer into polymer via a localized exothermic reaction zone that propagates through the coupling of thermal diffusion and the Arrhenius reaction kinetics of an polymerization. The definition,reaction mechanism and prominent characteristics of the frontal polymerization are reviewed in this article. The conditions for the existence of free-radical thermal frontal polymerization are considered.
摘要:The progresses in the kinetic and mechanistic study on living/controlled carbocationic polymerization of isobutylene by in-situ attenuated total reflectance Fourier Transform Infrared spectroscopy (ATR-FTIR) were reviewed with 26 references.
摘要:Surpercritical CO2 is an environmentally benign medium. In this paper,some recent work on the application of supercritical CO2 in polymerization and polymer processing is introduced,including some of our results.
摘要:For the blends systems with two components including crystal polymer,the crystallization behaviors of the crystal polymer will be influenced by other component,the structure and properties of the materials will be changed finally. During improving the properties of the polymer blends including crystal polymer,the influence of blends on the crystallization behaviors,such as the crystallization rate,crystalline style and crystalline size,are reviewed in present article.
摘要:Fluorosilcone polymer has many excellent properties,such as high and low temperature-resistant,climate- resistant,corrosion-resistant,water-and-oil-resistant,and chemical stability. Therefore,it attracts increasing attention from many scientists in recent years. In this paper,the preparation and application of the fluorosilicone polymer are introduced.
摘要:Three main crystal phases of poly(vinylidene fluoride):α, β and γ phases were reviewed in this paper .The article focused on the effects of different conditions on PVDF crystal phases and the transition in three crystal phases .The other crystal phases were also introduced .It is necessary to develop the application of PVDF materials by its' crystal polymorphism.
摘要:In this paper the progress of plastic and its composite tribo-materials is reviewed. Polymer alloys of PTFE,PEEK and UHMWPE and their composites are considered the key research areas in future. Considering plastic characteristics,plastic element design will be helpful to heat dispersion and the thermal resistance of plastics and ambient media resistance are also improved for tribological applications. Interfaces between plastic matrices and additives are still momentous. The future directions are tribo-polymer design based on modern material design,the creep and long-term stabilization,gradient function polymers and green tribo-polymers.
摘要:According to the characteristics of polymer physics, the author created the multimedia courseware with Authorware 6.5, Powerpoint 2000 and Flash MX, and got perfect teaching result .