最新刊期
卷 24 ， 期 11 ， 2011
- 摘要：Structural characteristics of the basic resin for polyethylene of raised temperature resistance (PE-RT)pipe were introduced. The recent development of PE-RT pipe and basic resin at home and abroad were aslo reviewed detailedly. Moreover, properties of all obtainable PE-RT resins in market were summerized.关键词：Polyethylene of raised temperature resistance;Pipe;Basic resin;Structural characteristic
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发布时间：2022-09-18 - 摘要：At present, one of the most fascinating subjects in areas such as nanoscience and biomimetic chemistry is concerned with the construction of novel complex macromolecular and supramolecular architectures with well defined shapes and functions by using specifically designed organic building blocks. In coil-rod-coil tirblock molecular system, the anisotropic orientation of the rod segments and the repulsion between the covalently connected blocks lead to self-organization into a wide variety of aggregation structures that can be manipulated by variation of coil volume fraction, molecular length, cross-sectional area of coil segment, the side groups in the center of rod segment, as well as the shape of the rod segments. The various parameter influence on self-assembly of coil-rod-coil triblock molecules was summarized in this article, the relationship between these parameters and the construction of the supramolecular structure was discussed, the work was significance of guiding on designing and synthesising the self-assembly molecules in future.关键词：Coil-rod-coil triblock molecules;Self-assembly;Supermolecules;Nano-structures;Xray diffraction
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发布时间：2022-09-18 - 摘要：Electrospun nanofibers with a high surface area to volume ratio have received much attention because of their potential applications for tissue engineering scaffolds and drug delivery carriers. Electrospinning is a simple and effective technique for the preparation of micro-nano fibers. Developed from the traditional electrospinning, the coaxial electrospinning is a new method that can prepare continuous core-shell nanofibers or hollow nanofibers through a one-step process, which further enhance the applications of nanofibers in tissue engineering and drug delivery. With a simple introduction of the principle of drug delivery, this review focuses on the principle and development of coaxial electrospinning and its applications in drug delivery.关键词：Coaxial Electrospinning;Nanofiber;Drug delivery
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发布时间：2022-09-18 - 摘要：Polyvinyl-chloride(PVC) is one kind of general resins with fine performances and low price, but PVC must be modified because of its brittleness, bad thermal stability and poor processability. These problem srestrict its further applications in some high-performance aspects. PVC compo sites with high performances can be obtained by blending with thermoplastic elastomer (TPE) to carry toughening modification. The blending of toughening PVC is the easiest method. In this thesis, the classification, toughening mechanisms and preparation methods were reviewed. The influencing factors of the early strength to PVC/TPE and the compatibilizing methods about immiscible polymer blend were also introduced.关键词：Poly (vinyl chloride);Thermoplastic elastomer;Blending;Toug hening modificatio n
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发布时间：2022-09-18 - 摘要：Infrared dichroism, an important technique in the study of polymer molecular orientation structure, has been applied in the research of polymer/inorganic nanocomposites. The recent research progress of orientation of polymer/inorganic nanocomposites are reviewed here in combination with the authors’work. First, the definition of nanocomposite as well as the basic principle of infrared dichroism technique are introduced. Then, some examples of the application of infrared dichroism in the orientation studies of pure polymer are presented. Finally, the orientation studies of infrared dichroism in polymer/inorganic nanocomposites are mainly reviewed.关键词：Infrared dichroism;Orientation;Polymer;Nanocomposites
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发布时间：2022-09-18 - 摘要：Ordered porous films have important applications in many fields such as separation, catalyze, and biomedical engineering. The breath figure (BF) method, featuring in simple, effectual and environmental, has attracted extensive attentions in the numerous film preparation methods. Scientists have devoted themselves to the performance improvement of the BF method by making porous films with new materials and techniques. According to the latest research developments, the fabrication, modification and application progress of the BF based ordered porous films is reviewed in this article.关键词：Ordered porous film;Breath figure method;Templating method;Micropattern
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发布时间：2022-09-18 - 摘要：Fluorinated polymers have received much attention recently because of their excellent physical and chemical properties. According to different monomers, fluorinated polymers with different structures can be synthesized by different method such as controlled/’living' polymerization: atom transfer radical polymerization (ATRP ), atom transfer radical-self-condensing vinyl polymerization (ATR-SCVP), reversible addition-frag mentation transfer (RAFT), nitroxide-mediated polymerization (NMP), living cationic polymerization, living anionic polymerization, oxyanion-initiated polymerization; conventional free radical polymerization, emulsion polymerization and so forth. Living polymerization can provide the narrow molecular weight distribution and high conversion to polymers and polymerization. Polymers with different structures like linear, star-shape even branching can be synthesized through these methods. The recent progress of polymerization have been reviewed in this paper.关键词：Fluorinated polymers;Cont rolled/living polymerization;Conventional free radical polyme rization;Emulsion polymerization
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发布时间：2022-09-18 - 摘要：Pretreatment technology of natural fiber is the key factor which affects biological composites which are reinforced by natural fiber. First of all, form physical properties, chemical composition and moisture absorption of natural fiber, this article reviews properties of natural fiber. For another, in view of these properties, this article in detail reviews domestic and overseas pretreatment methods of natural fiber and mainly introduces chemical methods of alkaline treatment, silane treatment, permanganate treatment and peroxide treatment, compares the results of natural fiber which is treated by ordinary chemical modification methods; and introduces physical methods of mechanical processing, low temperature plasma technology and steam blasting technology and other biological methods. Finally, this article prospects some existing problems and future development direction of modification technology.关键词：Natural fiber;Biological composites;Pretreatment;Modification technology
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发布时间：2022-09-18 - 摘要：The polymeric porphyrin and Co (Ⅱ) 、Mn (Ⅱ) and Zn (Ⅱ) complexes have prepared with meso-5, 10, 15, 20-tetra (hydroxyphenyl ) porphyrin and terephthaloyl chloride by interfacical polycondensation. Their structures were charactered with infrared spectra (IR) , scanning electron microscope (SEM) and X-ray photoelectron spectroscopic (XPS) analysis. It showed that the film of the polymeric porphyrin was synthesis by two-dimensional polymeric method, compared with the typical crystal structure of porphyrin unit. When the metalloporphyrins were synthesis, a pair of proton in which N-H bond is replaced by metal coordination, there N1s orbital electron binding energy changes less than0.2eV. The other two N atom of the porphyrin ring are coordinated to the metal coordination formation σcoordination bond, effect of the M2p3/2 of metal coordination electron binding energy changes more than 0.5eV. The porphyrin ring inner electron density was changed when metal ion coordination to ligand L.关键词：Interfacical polycondensation;Porphyrin;Metal complexes;Film structure
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发布时间：2022-09-18 - 摘要：Styrene-maleic anhydride copolymer is a synthetic copolymer with interesting features from both the chemical and the biological points of view. The proportion of maleic anhydride is an important factor that influences its function. The structure of styrene-maleic anhydride copolymer was determined to be monocarboxyl/monocarboxylic salt by potentiometric and conductometric titration. The titration end point was determined by derivative method. A simple and speed potentiometric titration method was established according to that. This method was proved precise by element analysis.关键词：Styrene-maleic anhydride copolymer;Acid anhydride content;Titration
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发布时间：2022-09-18 - 摘要：This paper studied the effect of the annealing temperature, the content and Mw of PEG on the crystal and melting behavior of PLA. The results indicted that the crystallinity increased and crystal temperature increased with the addition of PEG. All samples showed double melting peak after annealing 120min. The Tm1 and ΔH1 of samples annealing at 100 ℃ is hig her than that annealing at 80 ℃; The Tm1 of samples G was heightened and the ΔH1 of samples was enlarged with the increase of Mw of PEG.关键词：PLA;Double Melting Peak;Cry stallization Behavior;Melting behavior
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发布时间：2022-09-18 - 摘要：In the present paper, epoxidized natural rubber (ENR) was developed with in-situ formed performic acid. The structure of ENR was characterized by FTIR, and the distribution of the epoxide groups of ENR was studied by 13CNM R spectra and DSC. The results showed that performic acid was able to penetrate the latex droplet and effect epoxidation evenly throughout the droplet. The epoxide groups were random distributed in the molecular chain of epoxidized natural rubber.关键词：Epoxidized natural rubber;Epoxide groups;Distribution
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发布时间：2022-09-18 - 摘要：Copolymerization of vinyl group of hemin and N-vinylpyrrolidone was performed, and the water-soluble porphyrin polymer of hemin-poly (N-vinylpyrrolidone) was obtained. The structure of the polymer was characterized using 1H NMR, IR spectra and GPC chromatography. Meanwhile, the effect of dosage of initiator and ratio of the two monomers on the polymerization reaction was studied. The results showed that the copolymerization between vinyl group of hemin and N-vinylpyrrolidone occurred and a cross-linking copolymer was obtained.关键词：Hemin;Poly(N-vinylpyrrolidone);Copolymerization
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发布时间：2022-09-18 - 摘要：The energy shortage has become a global question, so the use of nuclear power has become an important way to solve energy shortage. The nuclear power development has brought the broad development space for the nuclear power station electric cable material. The study, development and application of the nuclear power cable material is of vital significance for China nuclear power. The classification, performance, preparation methods and research status at home and abroad on the nuclear power cable materials, were reviewed in this paper. In addition, the development trend of nuclear power cable materials was previewed.关键词：Nuclear power cable materials;Research status;Preparation;Progress
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发布时间：2022-09-18 - 摘要：The nature of the glass transition of polymer has been a perplexing problem to the material science researchers, and attracting much research using various kinds of methods. Fourier transform infrared(FTIR)spectroscopy has been widely used to follow the polymer structure changes during glass transition by a lot of researchers for its sensitivity to polymer structures. There were quantities of reports on this, and these reports were introduced in this paper. Most of the research always focused on the conformation changes during glass transition. However, how to make full use of the FTIR spectrum to investigate the glass transition more deeply is supposed to be the new direction in the future research.关键词：Glass transition;FTIR;Conformation
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发布时间：2022-09-18 - 摘要：Based on the explorations conducted in the curriculum construction of the National Key Technical College Project, this paper mainly deals with the specific concept and practices currently adopted in the project-oriented professional curriculum teaching reform of Polymer " Synthesis Technology" in LNPC from such aspects as the integration of curriculum system, the updating of the curriculum criteria, the selection and implementation of the project-oriented curriculum content, the establishment of the evaluation system and the construction of the databank of the instructional resources, which highlight the imprtance of the work-oriented project teaching reform in the cultivation of the students’professional skills. We have intended to optimize the course structure by strengthening the curriculum construction to create a unique curriculum construction mode characterized by the work-oriented projects and further improve the curriculum construction level and the teaching quality to meet the corporate requirements for the skilled talents.关键词：Technical college;Curriculum reform;Project-oriented teaching
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发布时间：2022-09-18 - 摘要：Practice teaching is the most important part in cultivating college students’innovative thinking, the ability of innovation and practice. This paper deals mainly with the current situation and existing problems on practice teaching of Polymer Material and Engineering, summarizing the important role of experimental teaching, productive practice, Graduation Design in the process of personal training. For the existing problems and deficiencies of practice teaching, we will focus on constructing a new training mode and practice teaching environment, increasing the proportion of study-based, exploratory practice teaching contents so as to lay a good foundation for training the professionals with innovative thinking and the ability of practice.关键词：Practice teaching;Reformation;Innovative thinking;The ability of practice
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发布时间：2022-09-18
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