最新刊期
卷 29 ， 期 8 ， 2016
- 摘要：Enzyme is a green, safe,efficient and specific biocatalyst with advantages of low energy consumption, recyclability and high selectivity. It is more important that enzyme-catalyzed polymerization may lead to polymers which cannot be (easily) prepared by conventional chemical catalysis. Therefore, enzymatic polymerization possesses definite potential for industrialization. This review describes the development of enzyme catalyst, its catalytic mechanism as well as its character of preparation for polymeric materials with special structure and functionality. The lipase-catalyzed ring-opening polymerization is especially advantageous to condensation polymerization with the aspects of mid reaction condition and good control over molecular weight and structure. Therefore,lipase-catalyzed ring-opening polymerization to synthesize polymers of different topologies (linear,branched,crosslinked) is emphasized.关键词：Enzyme;Lipase-catalyzed;Ring-opening polymerization;Topologies
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发布时间：2022-09-12 - 摘要：Researches on the factors enhancing and toughening rigid PVC were descried. The latest progress in enhancing and toughening rigid PVC were reviewed. The methods and mechanism of modifying interfacial compatibility between the matrix and filler or other polymers were discussed, the mechanism including multiple crazings,shear yielding, shear yielding-crazings, percolation theory, holes. The methods contain PVC/modified inorganic filler, such as micron particles,nanoparticles, core-shell structure particles and other inorganic particles; polymers, inorganic/polymers and graft modification.关键词：PVC;Enhancing;Toughening
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发布时间：2022-09-12 - 摘要：Collagen represents the major structural protein found in the human body, self-assembling into the fiber with a repeating D-periodic gap/overlap spacing, is the main organic building block of many biological tissues in vivo. Collagen has been widely applied and researched in many scientific fields, such as materials science,biomedical,tissue engineering, biosensors and so on,mainly due to its characteristic biodegradability,high biocompatibility,non-toxic,low immunity compared with other biopolymers. In the last few years, collagen was found to self-assemble into the ordered supramolecular structures at appropriate conditions in vitro, which has received great attention of researchers, has been becoming a hot research. This review will focus on the self-assembly mechanism of collagen,the influence of external environmental conditions on the self-assembly of collagen and the self-assembly of collagen-based composite materials.关键词：Collagen;Self-assemble;Supramolecular structure
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发布时间：2022-09-12 - 摘要：As one of the most important aliphatic polycarbonates,poly (trimethylene carbonate) (PTMC) has been widely studied because of its well-documented biocompatibility,biodegradability and rubber-like properties. This paper summarized the synthesis methods of PTMC,such as cationic,anionic,enzymatic ring-opening polymerization,microwave radiation polymerization and coordination polymerization, and discussed the effect of molecular weight on the physical properties of PTMC. Furthermore,the degradation behavior of PTMC in vitro and in vivo was especially discussed with the description of the role of molecular weight as well as enzymes on the degradation behavior of PTMC. At last,this paper summarized the potential applications of PTMC in biomedical fields.关键词：Poly (trimethylene carbonate);Ring-opening polymerization;Physical properties;Degradation behavior;Biomedical materials
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发布时间：2022-09-12 - 摘要：Due to their excellent electrical,thermal,optical,mechanical properties and high aspect ratio,carbon nanotubes (CNTs) have great application potentials in energy storage,biomedicine,catalyst supports, air and water filtration, and composites, among others. Precise and controllable positioning of CNTs between a pair of electrical conductors is the prerequisite for many of their applications. As a promising way, dielectrophoresis (DEP) has been frequently used for this purpose. This paper introduces the theory of DEP and analyzes the effect of DEP parameters on the results of CNT assembly. The research progress on DEP control with respect to the position and quantity of assembled CNTs has been reviewed.关键词：Carbon nanotube;Dielectrophoresis;Assembly;Control
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发布时间：2022-09-12 - 摘要：Polymer/surfactant mixtures are widely used in medicine, biochemistry, petrochemical industry, etc. The understanding on the interaction of polymer and surfactant is significant to guide their application, which therefore attracts many attentions from researchers in this field. With the recent advances in molecular simulations,the interaction of polymer and surfactant has been extensively studied at the molecular level. This article reviews the researches on the interaction of polymer and surfactant in the solution or at the interface based on dissipative particle dynamics (DPD) and coarse-grained molecular dynamics (CG-MD) methods. This review is mainly focused on the neutral polymer/ionic surfactant system and the opposite charged polymer/surfactant system in order to reveal the aggregation behavior of different polymer/surfactant mixtures.关键词：Polymer/surfactant mixtures;Dissipative particle dynamics;Coarse-grained molecular dynamics;Aggregation behavior;Interaction
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发布时间：2022-09-12 - 摘要：Dye-sensitized solar cells (DSSCs) are attractive candidates for the next generation of solar energy conversion. Owing to their low-cost materials, simple fabrication process and high energy conversion efficiencies and so on, dye-sensitized solar cells possess broad research interests and great potentially commercial applications. A DSSC typically consists of a dye-adsorbed photoelectrode layer, a counter electrode, and electrolyte. The electrolyte, as one of the key component in DSSCs, would have a significant influence on ions diffusion,charge transport and dye regeneration, thus affecting photovoltaic performance of DSSCs. In this review,we mainly focus on recent research developments of quasi-solid-state dye sensitized solar cells. Three aspects including polymer gel electrolytes, low molecular mass organic gelator and inorganic nano-particle gel electrolytes are highlighted. Finally,the future research trend of quasi-solid-state electrolyte for enhanced DSSCs is also prospected.关键词：Dye sensitized solar cell;Quasi-solid-state;Electrolyte;Power conversion efficiency
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发布时间：2022-09-12 - 摘要：Natural chitin which is widely abundant, biodegradable and biocompatible with nontoxicity and low immunogenicity,is a biopolymer with poor solubility in water and common organic solvents,and thus its direct application is rather limited. Nano chitin (chitin nanocrystals or nanowhiskers and chitin nanofibers) isolated from chitin could disperse stably and homogeneously, which not only had the properties of chitin itself, but also had high aspect ratio,high surface area and low density. Moreover,nanochitins had reactive surface (-OH and -NHCOCH3, and residual -NH2 groups) that facilitated surface fuctionalization. In this context,the methods isolated nanochitins including hydrochloric acid hydrolysis, 2 ,2,6 ,6-tetramethylpiperidinooxy(TEMPO) mediated oxidation,dissolution and regeneration process, partial deacetylation, mechanical techniques and electrospinning were reviewed, also the surface modifications of nanochitins and its applications in reinforcement,adsorption and biological activities were summarized.关键词：Chitin nanocrystals;Chitin nanofibers;Preparation;Chemical modification;Application
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发布时间：2022-09-12 - 摘要：A core-shell structured nanocomposite (CSN) with polystyrene (PSt )/organophilic montmorillonite (OMMT) as core and poly (butyl acrylate) (PBA) as shell were prepared through seed emulsion polymerization. The structure and morphology of CSN particle were examined through infrared spectrometry (FTIR),scanning electron microscopy (SEM) and transmission electron microscopy(TEM). CSN was spherical,with an evident core-shell structure. Through studying of seed dosage,core-shell quality ratio, amount of initiator and total monomers on the properties of emulsion, results showed that when seed dosage,core-shell quality ratio,amount of initiator and total monomers were 20% (wt),2:1,0. 6% (wt) and 45% (wt) respectively, the solid content and conversion rate of emulsion were higher,and water resistance,chemical stability and mechanical stability were better. Thermogravimetric analysis (TGA) showed that thermal stability of CSN was improved.关键词：Styrene;Organic montmorillonite;Seed emulsion;n-Butyl acrylate;Core-shell composite
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发布时间：2022-09-12 - 摘要：Sensitive silica/polymer composite microgel materials not only possess excellent chemical stability, hypotoxicity and easily functionality based on silica (SiO2 ) nanoparticles,but also present the environmental sensitivity to the external environment stimuli (such as temperature, pH,etc. ) inherited from stimuli-responsive polymer microgels. Therefore, this kind of composite materials are widely used in some important fields including drug release, adsorptive separation, carrier,microreactor, etc. According to the structures of sensitive silica/polymer composite materials,this review article will report the progress made in synthesis of three types of composite materials,namely silica/polymer core-shell composite microgels, polymer/silica core-shell composite microgels and hybrid network structure silica/polymer composite microgels.关键词：Silica;Polymer microgels;Sensitivity;Composite materials
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发布时间：2022-09-12 - 摘要：Ideal keratoprosthesis implantation material requires stable physical and chemical properties, excellent biological compatibility, high transparency, good air permeability and has certain refractive power, which make the implanted to reach the corrected visual acuity. Hydrogel has been widely used in the department of Ophthalmology,due to good biocompatibility and high permeability to water soluble metabolites such as glucose,nutrients, oxygen and so on. In this article, We provide a critical review of research and development of hydrogel-based artificial cornea from a materials perspective, including natural polymer hydrogels, synthetic polymer hydrogels, interpenetrating polymer network hydrogels and organic-inorganic composite hydrogels with high refractive index.关键词：Artificial cornea;Hydrogel;High refractive index;IPN
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发布时间：2022-09-12 - 摘要："Polymer physics" is the important discipline in polymer science, which provides a theoretical basis for the synthesis of polymers. The basic theories in "Polymer physics" are abstract. In this paper, the main viewpoints of the rubber elasticity theory, polymer solution theory,glass transition theory, polymer viscoelastic theory and polymer fracture theory were introduced, respectively. In addition, to enable students to better understand the key basic theory of polymer physics,the polymer solution,glass-rubber transition,viscoelastic properties and ultimate mechanical behavior were systematically analyzed.关键词：Polymer physics;Fundamental theory;Polymer
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发布时间：2022-09-12 - 摘要：The teaching status of chemical experiments for polymer major is described in this paper. Taking the synthesis of polyphenylene sulfide (PPS) as an example, the application of the response surface methodology in comprehensive chemistry experiments for polymer major is introduced. The main variables which effect on the results of experiment,the value range of variables and establishment and evaluation of models for fitting are discussed and the optimum condition is selected. Thus preliminary ability in scientific research for the students is trained. Also the ability of statistical analysis in dealing with the experimental data is enhanced and innovative thinking and teamwork spirit are cultivated.关键词：Response surface methodology;Experiment design;Experiment teaching
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发布时间：2022-09-12 - 摘要：In the information society, the analysis and utilization of literature is an essential skill for college students. Document visualization tools can display important elements of literature in visual form, which is helpful for understanding and mastering document. Taking the example of guiding the Innovation Training Program of College Students, the application of literature analysis software HistCite in the issue of torrefaction of biomass polymers was introduced. By using this software, the literature of torrefaction was analyzed. The major research institutes, authors, and key subject words were obtained from the analysis, and the visual literature chronological chart was also produced. This was beneficial for the understanding of the trends of the research field, hot issue and scientific frontier, thus helping the students to quickly master the development situation of the research field.关键词：Biomass polymer;Torrefaction;Literature analysis;Innovation program of college students;Teaching
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发布时间：2022-09-12
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