最新刊期
卷 29 ， 期 12 ， 2016
- 摘要：Natural polysaccharide nanogels have remarkable research value and a great deal of potential to the treatment of cancer, due to the excellent advantages, including a wide range of sources, low price, good biocompatibility and biodegradability et al. Furthermore, the internal structure of the crosslinked network in it can effectively improve the stability of the drug. It can also be modified with some targeting ligands or environmentally sensitive groups making the deliver drug to reach the target tissues and cells successfully, leading to the controllable release of drugs and thus to improve efficacy and reduce side effects of drugs. Actually, the properties of these natural polysaccharide nanogels are different, so the comprehensive utilization of their advantage should be advocated. In this review, we focus on the natural polysaccharide nanogels served as a drug carrier for cancer treatment, mainly including the environment-responsive studies and targeted drug delivery of chitosan, dextran, pullulan, alginates, hyaluronic acid, heparin et al. Furthermore, the trends of natural polysaccharide nanogels and their application prospect in terms of cancer treatment were summarized at the end of this review. For example, the structure stability and biocompatibility of natural polysaccharide nanogels can be improved by co-polymerizing with synthetic macromolecule. Moreover, it is urgent to develop a size-controllable synthesis protocol to obtain natural polysaccharide nanogels, which may increase the drug loading capacity. Although a great many of studies on the natural polysaccharide nanogels for drug delivery system, some problem, such as how to improve the stimulus response speed, drug loading efficiency as well as targeted drug delivery still need to be solved. In the future, it is necessary to develop more flexible targeting ligands to decorate the natural polysaccharide nanogels for the specific recognition target tumor cells, as well as introduce some functional organic groups which are sensitive to pH or glutathione, such as disulfide bond, to obtain multiple response intelligent nanogels materials, achieving controlled drug release.关键词：Nanogels;Biodegradation;Natural polysaccharides;Drug delivery;Targeted therapy
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发布时间：2022-09-12 - 摘要：With low density, high strength, low cost and recyclable, bamboo fibers is ideal reinforce filler in structural materials in engineering. Production of high performance polypropylene composites reinforced by bamboo fibers has been a pop research field. In order to obtain high performance composites, the interfacial interface between bamboo fibers and polypropylene matrix should be added. The three methods for improvement of compatibility between bamboo fibers and polypropylene matrix were summarized, including surface treatment of bamboo fibers, modification of polypropylene matrix, and loading other polymer matrixs. In addition, the trend of the future research was prospected.关键词：Bamboo fibers;Polypropylene;Compatibility;Composites
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发布时间：2022-09-12 - 摘要：Dynamic and static light scattering (DLS and SLS) are important methods for studying the sizes,shapes and conformation of macromolecules. They have been deeply applied in biochemistry,physics,medical pathology and other fields. In this article,the principles for DLS and SLS were introduced,and in addition,recent researches for application of DLS and SLS on proteins were investigated and reviewed by analysing the hydrodynamic radius,weight-average molecular weight,radius of gyration and second virial coefficient,and future development of application of DLS and SLS was prospected.关键词：Dynamic and static light scattering;Protein;Principle;Application
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发布时间：2022-09-12 - 摘要：In recent years, The output of natural plant fiber reinforced plastic composites showed a trend of increase sharply.However,the increase of products brings a problem of dispose of waste immediately.Efficient degradation of materials can solve the problem and promote the development of this kind of composite materials.In this paper, the main degradation methods of plant fiber reinforced plastics composites are introduced, the research status of degradation property from the aspects of light degradation,thermal degradation, chemical degradation, enzyme degradation and microbial degradation are summarized.and the problems of the materials to be solved are put forward.关键词：Natural plant fiber;Plastic;Composite material;Degradation property;Research progress
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发布时间：2022-09-12 - 摘要：Energy crisis and environment pollution make biodegradable plastics a significant research orientation to substitute for petroleum materials. Starch plastics become one of research emphasis of biodegradable plastics due to the non-toxic, low cost and biodegradable characteristics of starch. The properties of starch plastics will be easily influenced by the moisture, oxygen, ultraviolet light and flame of combustion in the environment. Studying how to reduce and eliminate these effects is assumed as "barrier properties". According to different inorganic substances, we mainly reviewed the effect of inorganic substances including oxide, metal salt etc on the barrier properties, which contain water resistance, flame retardancy, oxygen permeability and anti-ultraviolet properties of starch plastics. The latest research progress, problems are summarized in this paper; the trend in future is also proposed.关键词：Inorganic Substances;Starch plastics;Barrier;Progress
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发布时间：2022-09-12 - 摘要：Two kinds of RH catalysts [Rh(cod)Cl]2 and [Rh(cod)Cl]2 were synthesized with 1,5-cyclooctadiene(cod) and 2,5-norbornadiene(nbd) as ligands, using infrared absorption spectroscopy and nuclear magnetic resonance to characterize them, accurately determined the structure, and [Rh(cod)Cl]2 yielded up to 79.4%. With four kinds of chiral ammonia as cocatalyst and [Rh(cod)Cl]2 or [Rh(cod)Cl]2 formed catalytic system to polymerize the substituted phenylacetylene monomer(1) that containing dodecyl, according to the helical selective polymerization mechanism induced the chain helical structure of polymer and the weight-average molecular weight up to 493.9 thousand; In addition,[Rh(cod)Cl]2 catalyzed substituted phenylacetylene mononer(2,3,4) that contanis L-propane ammonia ether, L-valerian ammonia ether, and L-styrene acrylic ammonia ether for asymmetric polymerization under the action of no cocatalyst for the first time, the yield and molecular weight of three kinds of polymer are both high, in accordance with the helical selective polymerization of the ligand induced helical structure of three macromolecule main chain, and the main chain cis configuration of Poly(2), Poly(3) and Poly(4) is 70%, 77% and 77% respectively, thus achieved ideal catalytic effect.关键词：Rhodium catalyst;Cocatalyst;Substituted phenylacetylene;Catalytic polymerization;Helical structure
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发布时间：2022-09-12 - 摘要：At present, degree of polymerization of commercial dissolving wood pulp cellulose fibers is about 500~1800, and their molecular weight has polydispersity. Therefore, dissolving pulp with different characteristics was selected as cellulose fiber raw material, and effect of addition of hydrogen bond acceptor in NaOH aqueous solution on dissolving heterogeneous cellulose material was discussed in this paper, combined with fiber quality analysis. The results showed that dissolving capacity of NaOH/additives aqueous solution to dissolving pulp cellulose fibers is closely related to coarseness of pulp cellulose fibres in aqueous solution, rigid degree of fiber and types of additives, different from dissolving pure cellulose. And dissolution of longer cellulose fibers was improved in solvents with mixed additives, a small amount of sodium sulfamate, and sodium cyclamate.关键词：Dissolving pulp;Cellulose;NaOH aqueous solution;Dissolution;Fiber analysis
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发布时间：2022-09-12 - 摘要：Stereospecific Polyacrylonitrile was prepared via reversible addition fragmentation chain transfer (RAFT) polymerization. The chain transfer agent methyl (ethoxycarbonothioyl) sulfanyl acetate (MESA) was synthesized and characterized with 1H NMR. Polymerizations of acrylonitrile of different feeding ratio with MESA as the chain transfer agent and Ethylene carbonate as solvent were carried out at 60℃, affording polyacrylonitrile with higher molecular weight(Mn=5.60×104g/mol) and narrowerpolydispersity (PDI=1.15). The RAFT polymerizations of acrylonitrile in presence of AlCl3 were further undertaken in order to synthesize PAN with simultaneously controlled molecular weight and tacticity. The influence of the amount of the added Lewis acids and different monomer concentration on the polymerization was studied. The addition of AlCl3 in RAFT of acrylonitrile led to polyacrylonitrile with higher molecular weight (Mn=6.1×104~6.5×104g/mol), narrower polydispersity index(PDI=1.31~1.38)and an improved meso content (mm=32.1%~32.6%) under the optimum reaction condition used.关键词：Living radical polymerization;RAFT;Stereospecific;Polyacrylonitrile
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发布时间：2022-09-12 - 摘要：The safty and degree for the extractable and leachable of polymer material used in storage and transportation of the process liquid in medical, pharmaceutical and food industry have attracted more and more attention by public. For extractalbe test,it is important to determine simulation solvent system based on actual liquid product ingredients. After explaining the principle of solvent selection and theory of solvent classification, the review propose the two solutions for selection simulation solvent in extractable experiment, based on the Induction and summary of reported article and literature. It can provide researchers with ideas and advice for design and evaluation simulation solvent system in extraction experiment in the future.关键词：Extractable;Simulation solvent;Solvent strength;Polar
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发布时间：2022-09-12 - 摘要：As an important teaching part of polymer materials and engineering major, the production practice plays an important role in improving the practical ability, and even comprehensive qualities of the students. In order to solve the current problems of production practice in our college, multimedia simulation training is introduced as the entrance of production practice. Depending on the multimedia simulation, the production practice can be carried out from the unit training, and transformed step by step to large-scale polymerization apparatus. The introducing of multimedia simulation declares the mode of the production practice in our college has transformed from the only plant mode to combined mode, i.e., the plant and digitized simulation mode. In addition, more and more plants have been listed as our practice base. With the strict assessment system, after several years of reform and practice, we have achieved a good effect on production practice.关键词：Polymer material and engineering major;Production practice;Simulative practice;Practical ability
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发布时间：2022-09-12 - 摘要：Polymerization reaction engineering is a specializes course which has a distinct engineering practicality. It is indispensable in polymer science knowledge system which translates theoretical knowledge into Industrial practice application. According to the "professional chemical engineer" teaching guidelines for cultivation objectives, the reform concerning teaching contents and teaching method is advocated by the author. In teaching process, cultivating students’ engineering thinking, paying attention to visualized teaching and practical teaching as well as enhancing the professional emotional education are adopted, which can guide the student to a deeper understanding of the courses.关键词：Polymerization reaction engineering;Engineering and analysis;Visualized teaching and practice teaching;Professional emotional education
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发布时间：2022-09-12 - 摘要：The application oriented personnel training in China is facing the transformation and upgrading, so most colleges and universities are actively promoting bilingual teaching, which could improve students’ ability to adapt to the cross regional and cultural communication of science and technology information. In this paper, based on my last 6 years of polymer chemistry bilingual teaching experience with the aim of application oriented personnel training, the experience and summary about the bilingual teaching of polymer chemistry were introduced in detail, such as teaching in classroom, practice outside the classroom, probation education and practice teaching, communication between teachers and students, and so on. In addition, the progress of polymer chemistry bilingual teaching in the area of college students’ cultivating were also illustrated and summarized, and the results showed that the most college students’ foreign language literature reading professional ability and learning ability were improved prominently.关键词：Polymer chemistry;Bilingual teaching;Application oriented personnel training
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发布时间：2022-09-12
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