最新刊期
卷 27 ， 期 10 ， 2014
- 摘要：As a very important kind of novel organic functional materials, micro- and nano-structured conducting polymers have become a hot research topic of organic material science field in recent years. This article mainly reviews the chemical and electrochemical methods for the controllable synthesis of conducting polymers with micro- and nano-structured morphology. The two synthesis methods are further divided into three main aspects: hard-template, soft-template, template-free self-assembly synthesis. In addition, the formation mechanism of conducting polymer micro- and nanostructures, obtained by these methods in previous publications, is discussed.关键词：Conducting polymer;Micro- and nano-structures;Synthesis methods
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发布时间：2022-09-18 - 摘要：This paper reviewed the development of protein-based multilayer assemblies. The assembling mechanisms, building blocks and physical morphologies such as coating,microcapsule and nanotubes of the protein assemblies were introduced in detail. Their biomedical applications such as antibacteriality,anticoagulation,bioactive coatings, controlled drug delivery and bioseparation were summarized as well. The advantages as well as the future developments of the protein multilayer assemblies were also addressed.关键词：Protein;Layer-by-Layer self assembly;Biomedical application
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发布时间：2022-09-18 - 摘要：The doped polyaniline (PANi) exhibits favorable conductivity as an excellent structural conductive polymer due to its high degree of delocalization on the main chain. The large specific surface area of PANi nanofibers make it easier to obtain higher conductivity. This paper introduces the research and development of PANi composite nanofibers prepared by electrospinning method in recent years at home and abroad, focusing on the PANi /PEO composite nanofibers, PANi / PAN composite nanofibers, PANi /PMMA composite nanofibers and PANi /PLA composite nanofibers and so on as well as theirs potential applications fields such as battery separator, sensors, electromagnetic shielding materials, absorbing materials, etc.关键词：Electrospinning;PANi;Conductive polymer;Nanofibers
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发布时间：2022-09-18 - 摘要：The reversible addition-fragmentation chain transfer (RAFT) polymerization was a new living/controlled radical polymerization. The application of RAFT polymerization of synthesize polymers with narrow molecular weight has unique advantage,The mechanism, characteristics and the choices of RAFT reagents were introduced in the paper. RAFT polymerization has exhibited wide applications in molecular structure design,such as random, block, gradient, graft, star, dendritic and comb copolymer. In addition, the development and research trend of RAFT were also presented.关键词：Reversible addition-fragmentation chain transfer;RAFT polymerization;Molecular design
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发布时间：2022-09-18 - 摘要：Metallized modification on the surface of polymer materials is a widely used technology. Some special characteristics , such as high mechanical strength, abrasion performance and electrical conductivity,can be achieved through the metallized modification; sometimes, it is an important means for fine processing on polymer surface. Besides, doing the metallized modification doesn't change the basic properties of polymer materials,such as the low density, easy to be processed and other superiorities. Polymer materials after being surface metallized have a high additional values and with great prospective market potential in various application fields. So it gained a significant progress in recent years. In this paper,some methods of preparation and characterization for metallized modification on the surface of polymer materials were described and the applications of metallization polymer were also introduced.关键词：Polymer;Surface modification;Metallization;Progress
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发布时间：2022-09-18 - 摘要：The poor chlorine-resistant performance of the aromatic polyamide nanofiltration/reverse osmosis (NF/RO) membrane leads to short service life of the membrane and increased operation cost of the membrane system. Therefore, significant amount of work has been devoted to improving NF/RO membrane chlorine resistance. This paper reviews the reports on novel NF/RO membranes having superior chlorine resistance in recent years. The chlorination and degradation mechanism of aromatic polyamides was elaborated and the methods of preparing chlorine resistant composite membranes, including developing of new membrane fabrication process, exploring of new membrane materials, modification of traditional monomers, grafting and coating of current membrane surface,were summarized. By comparing the four different methods, the reports on chlorine resistant composite membranes were introduced and analyzed and the challenges and future prospects of the chlorine resistant NF/RO composite membranes were discussed as well.关键词：Polyamide composite membrane;Chlorine-resistant;Nanofiltration;Reverse osmosis
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发布时间：2022-09-18 - 摘要：Polyhedral oligomeric silsesquioxane (POSS) shows some of the important features, including the Si-O cage size and the distribution of the eight pendant arms from the cube in a three-dimensional arrangement. These cubic Si-O cages have thus become very popular as nanometer-scale building blocks in a wide range of polymeric materials. In this contribution, the recent development in the synthesis of POSS was reviewed, and in particular the synthesis method of T8R8, T8R7R', T8RnR'8-n and partially condensed POSS (T7) was described. Meanwhile, the synthesis ways and experiences about many POSS compounds were also summarized. Finally, the potential development in the synthesis of POSS was also discussed.关键词：Polyhedral oligomeric silsesquioxane;POSS;Synthesis;Preparation
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发布时间：2022-09-18 - 摘要：Polyhedral oligomeric silsesquioxanes (POSS) as a new kind of organic-inorganic hybrid materials with special cage-like structure, has an effect on the crystallization behavior, degree of micro-phase separation and crosslinking density of the polyurethane system. It has been demonstrated that incorporation of small amounts of POSS into PU can significantly enhance the water resistance, thermal stability and mechanical properties. This article reviews some new insights into the relationship between the performance of POSS/PU nanocomposites and the structure of different POSS such as pendants, starburst,beaded and physical blend.关键词：Polyhedral oligomeric silsesquioxanes;Polyurethane;Nanocomposites;Structural modification
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发布时间：2022-09-18 - 摘要：During offshore gas drilling, methane can form gas hydrates with seawater at specific temperature and pressure and block the pipelines. This article provides a brief overview of the history of the development of polymers used for gas hydrate inhibition. The performance, mechanism and main factors of the low dosage hydrate inhibitors are discussed from structure-property relationships. Recent studies have found that antifreeze proteins from certain arctic fish and insects can not only depress the freezing point of water, but also inhibit the gas hydrate formation. Synthesis of polymers that mimic such antifreeze protein structures can be a new approach for development of gas hydrate inhibitors. Finally, a number of issues worthy of future research and applications are raised in the article.关键词：Water-soluble polymers;Natural gas clathrates;Antifreeze proteins;Kinetic hydrate inhibitors
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发布时间：2022-09-18 - 摘要：Methyltrimethoxysilane(MTMS) was used to modify novolac resin (Novolac) to improve the thermal stability of Novolac. Siloxane-modified novolac resin (SN) was prepared by ester exchange reaction at the molecular level. The influence of catalysts,reaction time and reaction temperature on the molecular weight of SN was investigated,the results showed that, the best catalyst was acetic acid,the most appropriate reaction time was 4 to 6 hours,and the optimum vacuum distillation temperature was 110℃. The results of structural characterization of SN showed that the reaction of one methoxy group of MTMS and phenolic hydroxyl groups of Novolac occupied the dominant position. The results of thermal stability of cured SN showed that,compared to cured Novolac, under nitrogen atmosphere, the maximum decomposition rate temperature of cured SN100 increased by 80℃,the maximum decomposition rate decreased by 42. 94 %,and the char yield at 1000℃ increased by 8. 97% , meaning that the introduction of siloxane could greatly enhance the thermal stability of Novolac.关键词：Siloxane;Novolac resin;Thermal stability
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发布时间：2022-09-18 - 摘要：Crosslinking of ultra-high molecular weight polyethylene fibers (UHMWPE fibers) is investigated by means of electron beam irradiation. The dose of irradiation is from 20kGy to 1000kGy. The structure and mechanical properties of the fibers with different irradiation dose are discussed. The results show that the gel content of the fibers increases with the increasing irradiation dose. There are two effects of electron beam irradiation on fibers, crosslinking and chain scission. Melting point and melting enthalpy of fibers decrease with the increasing irradiation dose. The average size of crystal of normal direction is also decrease with the increasing irradiation dose. The thermal dimensional stability of fibers increases with the increasing irradiation dose.关键词：Ultra-high molecular weight polyethylene fiber (UHMWPE fiber);Electron beam irradiation;Crosslinking;Thermal dimensional stability
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发布时间：2022-09-18 - 摘要：The surface of polymer solar cells is soft and sticky, which affect the scan of AFM tip seriously and influence AFM observation. In this study, tapping mode, ScanAsyst mode and FastScan mode were used to analyze the morphology and phase separation of polymer solar cells. And the effects of scanning parameters, such as types of tips, control of interaction force between sample and tip and scan rate were discussed. Results demonstrate that AFM tips with low elastic coefficient and reflective coating are good for the detection of polymer solar cells. And it is very helpful to control low interaction force. In addition, high scanning rate is not favorable for getting good morphologic image,thus the scanning rate should be controlled. It is important to select appropriate parameters and imaging mode in characterization of polymer solar cells.关键词：Atomic force microscopy;Polymer solar cells;Morphology characterization
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发布时间：2022-09-18 - 摘要：Acoustic velocity method was applied to study the molecular chain orientation factor of PAN nascent fiber obtained by dry-wet spinning and wet-spinning processes, respectively. The results indicated that with the increasing of shear rate and drawing ratio, the molecular orientation factor of the nascent fiber gradually improved. In the case of dry-wet spinning,the elastic recovery process of PAN molecular occurred during the air gap, the pre-orientation structure obtained by shearing was disordered. In addition, the drawing stress was needed to overcome the internal stress generated by the viscous motion, the molecular orientation was lower than that of the nascent fiber obtained by wet-spinning. When the shearing force was increased, the orientation factor of the nascent fiber produced by wet spinning changed more obviously. On the other hand, the stretching force is benefit to the formation of orientation structure during dry-wet spinning compare to wet-spinning process.关键词：PAN nascent fiber;Dry-wet spinning;Wet-spinning;Orientation structure
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发布时间：2022-09-18 - 摘要：Aligned nanofibers could be prepared by magnetic-field-assisted electrospinning(MFAES) of which matching relations between the parameters was rarely studied. In this paper, based on the orthogonal design, four main technological parameters which influence the preparation of PAN fibers through MFAES was optimized and screened at three levels, including solution concentration, the distance between two magnets, spinning voltage and flow rate. Taking fiber diameter size、distribution and degree of fiber alignment as study objects, by means of range analysis and variance analysis, the effect of the interaction between any two factors of solution concentration, the distance between two magnets and spinning voltage have also been studied. The effect of above parameters are as follows : solution Concentration is a highly significant affecting factor on fiber diameters and uniformity, the interaction effect between solution concentration and spinning voltage is a significant affecting factor on fiber uniformity, spinning voltage is a significant affecting factor on fiber ordering.关键词：Magnetic-field-assisted electrospinning;Orthogonal design;The size and distribution of fiber diameter;The degree of fiber aligment
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发布时间：2022-09-18 - 摘要：Traditional therapeutics for tissue defection suffer fromimmune rejection and shortage of donor organs, thus much attention has been paid to bionic scaffolds with excellent performances for tissue engineering recently. It has been proven that the nanotopography of tissue engineering scaffold has a great impact on cell behaviors. This article mainly reviews the influence of scaffold nanotopography, including the different structures,fiber diameters, fiber orientations and porous sizes, on cell adherence, proliferation, migration, protein secretion, and differentiation direction. The possible mechanisms of interaction between nanotopography of tissue engineering scaffolds and cells are summarized. Meanwhile, the prospect is also presented from two aspects : research on systematic theory for the impact of scaffold nanotopography on cells and construction of porous-fiber-formed scaffold.关键词：Tissue engineering;Scaffolds;Nanotopography;Cells;Interaction
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发布时间：2022-09-18 - 摘要：Most of the polymer-supported metal catalysts have obvious advantages such as high catalytic activity, easy separation and purification of product after reaction and easy recovery and reuse several times without any remarkable loss in catalytic activity. Cellulose is one of the most abundant natural polymer on earth. It is stable in most organic solvents, has high surface area and hydroxyl functional groups that are capable of chelating to metal ions and particles thereby providing required stability. In addition, it is biodegradable, non-toxic and available at low price. In this paper, synthesis of cellulose- based metal catalysts and their applications in organic transformation were summarized.关键词：Cellulose-supported catalyst;Organic reaction;Metal;Heterogeneous catalysis
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发布时间：2022-09-18 - 摘要：Polymer Physics is a science to describe the motions of long-chain polymer molecules and their relationship with the properties of polymer materials. It has many important fundamental concepts in the polymer physics. As a result, this paper introduced the meaning and role of the important fundamental concepts relating to the chain structure, the condensation states structure,polymer solution,viscoelasticity,molecular motion and transition,and ultimate mechanical properties of the polymer by focusing on the particularity of polymer long chain to understand the equations and important fundamental theories in polymer physics.关键词：Polymer physics;Fundamental concepts;Polymer;Structure;Motion
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发布时间：2022-09-18
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