最新刊期
卷 18 ， 期 6 ， 2005
- 摘要：Cyclodextrin polymers (CDPs) not only have the inclusion ability,the controlled release ability,the catalysis ability and the selective ability,like their parent CDs,but also have fine mechanical intensity and the excellent stability.In addition,they exhibit various physical properties that have been impossible to obtain with their parent CDs.These lead CDPs to much attention.In this paper,progress in the preparation methods and the types of CDPs was summarized and application of CDPs in the enantiomer separation of chiral pharmaceuticals,improvement of the drug release,increase of the drug solubility,molecular imprinting technique and the drug delivery system was reviewed.关键词：Cyclodextrin polymers (CDPs);Enantiomer separation;Molecular imprinted polymer;Drug release;Drug delivery system
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发布时间：2022-09-18 - 摘要：Microcellular plastics is a newly-developed material which cell size is less than100μm.In this paper, the development of microcellular foaming mechanism is reviewed.Three critical progresses of microcellular foaming mechanism (the formation of polymer-gas homogeneous phase system,nucleation,bubble growth and shaping) are discussed respectively,and some fundamental models and theories of them are introduced.Lastly,some proposals of mechanism study are put forward and the prospect of microcellular foaming study is proposed also.关键词：Microcellular;Foaming mechanism;Development
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发布时间：2022-09-18 - 摘要：This paper reviews recent developments of the hydrophilic modification of porous polymer membranes by the low temperature plasma method,with46references referred.After a brief description of the plasma principle, three plasma treatment techniques,plasma surface treatment technique by some unreactive and reactive gas,such as Ar,He,O2,N2,CO2,H2O,NH3 and SO2,plasma deposition polymerization by saturated and unsaturated monomers,such as alkyl alcohol,alkyl amine,allyl alcohol,and allyl amine,and plasma induced graft polymerization by the alkene monomer with a polar group,are discussed applying in the membrane surface hydrophilic modification.Their effects on the chemistry structure and morphology structure of both the membrane surface and pore wall,on the degree and permanence of the hydrophilicity,and on the improvement of water flux and the protein antifouling of the modified membrane,are summarized.关键词：Plasma;Porous polymer membrane;Membrane surface;Hydrophilic modification.
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发布时间：2022-09-18 - 摘要：Better understanding the thermal behaviors of polyurethane would give a more practical useful material. In this paper, thermal degradation mechanisms of polyurethane under different environmental conditions are critically reviewed. Recent studies on the kinetics of polyurethane are introduced.关键词：Polyurethane;Thermal degradation mechanism;Thermal degradation kinetics
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发布时间：2022-09-18 - 摘要：In recent years,polymer-supported catalysts developes very rapidly due to their advantages such as easily separating and recycling.In this paper,the applications of polymer-supported cinchona derived chiral catalysts in the synthesis of α-amino acids have been discussed.Moreover,the latest progress and the trend of further development in the field also have been reported.关键词：Asymmetric synthesis;Polymer supported;Chiral catalyst;Phase transfer;Cinchona
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发布时间：2022-09-18 - 摘要：Chitosan has very useful functional groups such as hydroxyl,amine and acetamide groups,so it can interact with transition metal ions.In this part,the review is a closer look at the adsorption mechanism and structures on metal complexes of chitosan and its derivatives.Based on current research,some new and futuristic approaches are thoroughly discussed.关键词：Chitosan;Derivatives;Metal ions;Structure;Adsorption mechanism
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发布时间：2022-09-18 - 摘要：An overview of recent developments of halogen-free flame retardant polymers containing phosphorus is presented in this paper.Two approaches to the achievement of flame retardancy in polymers were generally known as the additive-type and the reactive-type.Some aspects of these polymer systems such as synthesis,structure,property and applications are discussed here in.关键词：Phosphorus;Halogen-free;Flame retardant;Polymer
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发布时间：2022-09-18 - 摘要：This paper reviewed new development of synthesis and surface-modification of polyurethane as biomaterials in details. Their advantages and disadvantages and unique physical and chemical properties of all kinds of polyurethane biomaterials were analyzed, and several critical surface-modifying methods were pointed out.关键词：Polyurethane;Surface-modification;Grafting;Biomaterials;Bioactive macromolecule
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发布时间：2022-09-18 - 摘要：This review highlights synthesis,catalytic properties of polymer-supported organic catalysts in the last 25 years,with emphasizing on some recent developments in the direction.The polymer-supported catalysts were first divided into achiral and chiral catalysts,and then divided into different sections according to the chemical reactions catalyzed.Some examples were included in order to make clear comparison based on the catalytic activity and selectivity.Some comparisons were made for achievability of separation and reuse of the supported catalysts.Different kinds of polymer supports were included,e.g.crosslinked polymers,soluble linear polymers and dendrimers.In this second part chiral organic catalysts were detailed.关键词：Organic catalyst;Polymer support;Chiral catalyst;Aminoacid;Peptide
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发布时间：2022-09-18 - 摘要：The nickel catalysts for ethylene oligomerization and polymerization are of special relevance to catalysis, because of the easy synthesis and various catalytic properties influenced by the characteristics of the attached ligands. Recent progress of late transition metal complexes as catalysts has led to a renaissance in designing novel catalysts for polyolefins beyond the famous SHOP process. The nickel catalysts are interested of the varieties of complexes containing different ligands, which are coordinated with nickel center as the bidentate and tridentate ligands. In contract to the important set of hetereogeneous catalysts, the homogeneous catalyst is a small share for polyolefins, however, the well_defined complexes affect the microstructure of their products. The properties of polyethylene can be affected with adaptation of ligands coordinating to nickel center, so do the oligomers obtained with nickel complexes. Attracted to chemists, auxiliary ligand can improve the catalytic activity in one order of magnitude. In addition to the fast catalytic reaction, the active center can be confirmed through isolating the intermediate which produce the reliable catalytic activity. In the chapter, the development and progress of nickel complexes as catalysts for ethylene oligomerization and polymerization are discussed, and their advantage and disadvantage are also listed with future potentials in academic research and industrial applications.关键词：Nickel complexes;Ethylene;Oligomerization
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发布时间：2022-09-18 - 摘要：The implants were prepared by biodegradable polymers and drugs with physical packing or chemical connection ways.The drug in the polymer can diffuse from the channel of polymer with constant speed.It can affect only in the local site rather than in systemic tissues.The development of polymer matrix,preparation method,release mechanism of drug for biodegradable implants were also reviewed.关键词：Biodegradation;Sustained release;Implant
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发布时间：2022-09-18 - 摘要：In recent years,more and more attention has been paid to supercritical carbon dioxide.This paper mainly reviewed the preparation of polymers that has been carried out in supercritical carbon dioxide.A number of polymerization reactions,such as free-radical polymerization,cationic polymerization,transition metal-catalyzed polymerization,thermal ring-opening polymerization,sol-gel polymerization and oxidative coupling polymerization are described in details.It indicates that supercritical carbon dioxide will have a great impact on the field of polymer synthesis in future.关键词：Supercritical carbon dioxide;Polymers;Polymerization;Synthesis
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发布时间：2022-09-18 - 摘要：Structure characterization of aromatic cyclic oligomers including its developing process and latest progress is reviewed in this article. HPLC, FAB-MS(FIB-MS), MALDI-TOF-MS, ESI-MS combined with other assistant methods are introduced respectively.Characteristics and application range of each kind of characterization method are compared.关键词：Aromatic cyclic oligomers;Characterization;HPLC;FAB-MS(FIB-MS);MALDI-TOF-MS;ESIMS
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发布时间：2022-09-18 - 摘要：Chitosan microspheres were prepared by ionically cross-linked chitosan with amphoteric N,O-carboxymethyl chitosan(CM-chitosan).CM-chitosan with a isoelectric point (IEP)2.86 was synthesized by chemical reacting chitosan with monochloroacetic acid,and the chemical structure was analyzed by IR and 13C NMR.By adding CM-chitosan into chitosan solution,microspheres were formed instantaneously,and the structure of microspheres was characterized by IR and microscopy.The observation of optical microscopy,scanning electron microscopy and transmission electron microscopy showed that the ratio of chitosan to CM-chitosan had more influence on morphology and size of the microspheres than ultrasonic power,indicating that the charge action between this two polyelectrolytes were the mechanism of microsphere formation.This mechanism was also confirmed by measurement the change of absorbance and conductivity with pHvalue of chitosan/CM-chitosan solution,the result also showed that the pH range for microsphere formation is IEP(CM-chitosan) <pH<pKa(chitosan).关键词：Chitosan;N,O-carboxymethyl chitosan;Ionically cross-link;Microsphere
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发布时间：2022-09-18 - 摘要：5-FU-loaded PLA ultramicron were prepared by a w/o/w emulsion evaporation method,and were characterized by transmission electron microscopy (TEM),particle size analyzer and UV spectrometer.The release performances of 5-FU loaded PLA ultramicron in vitro were studied.The VEGF/5-FU loaded PLA ultramicron labeled technetium-99m were injected in nude mice by tail vein to observe targerting effect and therapeutic effect.TEM observation showed ultramicron were spherical,The mean diameter was 195.2nm,and the index of polydispersity was 0.148, the drug content was 8.23%, and the encapsulation efficiency was 24.71%.There was a linear relationship between the amount of accumulative release Q and time square root t1/2.After targeted 5-FU loaded PLA ultramicron injection 2 hours,the majority of ultramicron centralized at tumor site.In all the treatment groups, 5-FU/VEGF loaded PLA ultramicron group had best result.That demonstrated 5-FU/VEGF loaded PLA ultramicron had multiple function with inhibition of growth of blood vessel of tumor and controlled release drug in the tumor site.关键词：Targeted ultramicron;Controlled release;VEGF monoclonal antibody;5-Fluorouracil
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发布时间：2022-09-18 - 摘要：Biodegradable aliphatic polyesters synthetic polymer scaffolds have been extensively applied in tissueengineering. Various methods have been explored for fabrication of porous scaffolds using PLLA,PGA as well as its copolymers,their porosity increased and pore structure was improved through modifications and combination of present ways.The methodologies with their modifications development are included in this review.关键词：Biodegradable;Aliphatic polyesters;Tissue-engineering;Porous scaffolds
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发布时间：2022-09-18 - 摘要：Application of inorganic nano-particals in modificating polymer becomes a hot topic due to the superior composite properties of polymer nanocomposites.In this paper,the types of nano-particals utilized in epoxy resin toughening,the preparation methods of epoxy/nanocomposites and their application are reviewed.关键词：Inorganic nano-particals;Epoxy resin;Toughening
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发布时间：2022-09-18 - 摘要：The recent research progresses in magnetic resin matrix composites were reviewed in this article. The magnetic resin matrix composites were classified into three kinds: bonded permanent magnet, magnetic polymer microspheres and magnetic ion exchange resins. These three aspects were related.关键词：Magnetic resin matrix composites;Bonded permanent magnet;Magnetic polymer microspheres;Magnetic ion exchange resins
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发布时间：2022-09-18 - 摘要：First-generation biomedical materials were biocompatible and bioinert materials.Second-generation biomaterials were designed to be either resorbable or bioactive.Third-generation biomaterials are combining these two properties.These new generation biomaterials are designed as the extracellular matrix to activate genes and elicit the specific interactions with cell,and thereby to direct cell proliferation,differentiation,organization,and last to repair or regenerate the living tissues and organs.关键词：Third-generation biomedical materials;Tissue engineering;Cell and gene-activation;Extracellular matrix;Bioactivity
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发布时间：2022-09-18 - 摘要：In this paper,various modified natural polymer such as starch,cellulose,chitosan,guar-gum and so on used as water control agent in oilfield were reviewed.And the tendency for natural polymer as water shutoff agent was also elaborated.关键词：Natural polymer;Profile modification;Water shutoff
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发布时间：2022-09-18 - 摘要：This paper introduces the history and characters of Monte Carlo technology and its wide application in polymer science. The author also made an outlook of its future.关键词：Polymer;Monte Carlo;Computer simulation
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发布时间：2022-09-18 - 摘要：This text introduced the characteristics of " The chemistry and physics of polymers" and of the exercises software,the development of the exercises software is also introduced.关键词：Exercises software;Development;The chemistry and physics of polymers
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发布时间：2022-09-18 - 摘要：CAI (computer assistant instruction) software of polymer viscoelasticity was designed based on Matlab/ Simulink.The computer programs consisted of various functional modules according to the viscoelasticity priciple of polymer.Experimental data and simulation parameters may be input and modified by clicking the corresponding modules.The direct-viewing simulation results will be obtained from the output modules such as oscilloscope,digital display and XY recorder.This software can demonstrate and simulate the viscoelasticity behavior of polymer both in static and dynamic state,such as hysteresis effect,dynamic mechanical loss,Boltzmann superimposition of strain and free vibration decay curve.The software can be used not only for instruction demonstration in polymer physics course, but also for design and study of polymer materials.关键词：Polymer viscoelasticity;Hysteresis;Boltzmann superimposition;Free vibration decay curve;CAI
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发布时间：2022-09-18 - 摘要：Multimedia Teaching System is designed by use of the multimedia technologies, with the multimedia producer Authorware playing the main role aided by the advanced language VB and other leading multimedia producers. It is made up of such eight modules as an introduction, radical polymerization, radical co-polymerization, ionic polymerization, coordination polymerization, the preparation method of chain polymerization, step reaction polymerization and chemical reaction of polymers. Each module is divided into four parts, that is, specific chapters, requirements of each chapter, extension and assignment, interface technologies make it come true to type in contents, delete, modify, search and reading material and so on. It can serve as not only an efficient tool for polymer chemistry teachers to teach in class, but also a helpful approach for students to do exercises and persue references. It is a useful supplementary computer teaching software with advantages of convenience, simplicity and high efficiency.关键词：Polymer chemistry;Multimedia;Teaching software
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发布时间：2022-09-18
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