最新刊期
卷 25 ， 期 11 ， 2012
- 摘要：Rod-coil systems (copolymers and complexes) have attracted increasing interest because they could self-assemble to a variety of ordering nanometer-scale domains including spherical or cylindrical micelles, lamella, vesicles and so on. This review presents an overview of the sort and the preparation of rod-coil systems, discusses in detail the self-assembly behavior and mechanism of rod-coil systems in solution, and particularly introduces the supramolecular rod-coil complexes. Finally, the outlook for the future of these systems is summarized.关键词：Rod-coil systems;Self-assembly;Solution
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发布时间：2022-09-18 - 摘要：Biomaterials, especially blood-contact materials, to meet antithrombogenic requirement is the first premise for clinical application. Surface modification for blood compatibility improvement is simple and feasible. Surface modification includes two aspects of surface design and method design. In the present paper, several surface design strategies for antithrombogenic polymeric materials including micro-phase separated structure design, surface phase seperation design, negative charge surface design, hydrophilic/hydrophobic surface design, bioactive surface design, endothelialization surface design, and zwitterionic surface design were reviewed. Among them, zwitterionic antithrombogenic surface design was highlighted.关键词：Blood compatibility;antithrombogenic materials;Molecular engineering surface Design;Zwitterionic biomaterials
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发布时间：2022-09-18 - 摘要：With the development of science and technology in genomics, biochemistry, molecular biology and peptide synthesis, protein drugs are becoming very important ones and widely used in clinical. However, the low stability, fast clearance and immunogenicity of protein drugs become the major hindrances in their efficient clinical applications. Thus, the polymer-protein conjugation becomes a more and more vital method to improve the efficiency of protein drug in clinic. In this paper, we discussed the development of the application of poly(ethylene glycol)(PEG) in the polymer-protein conjugation technology in recent years, and the advantages and limitations of this technology. And we also discussed the recent advance in other new polymeric materials and methods for the polymer-protein conjugation.关键词：Protein drugs;PEG;Polyacrylamide;Zwitterionic polymer
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发布时间：2022-09-18 - 摘要：A major field in cancer research is to develop carriers that can deliver drugs into targeted region effectively without side effects. Polymeric micelles (PMs) are core-shell structure with diameters of 10~100nm (suitable size with a narrow distribution could avoid rapid renal excretion and entrapment by the reticuloendothelial system), which are self-assembled with good biodegradable and biocompatible polymer to form hydrophobic core and hydrophilic shell in an aqueous media. The preparation of PMs with stimuli-responsive block copolymers and modification of target molecules on PMs’ surface could significantly improve the performance of the drug-loaded, enhance drug utilization and anti-tumor activity, reduce the normal tissue toxicity and solve the problem of multi-drug resistance, and thus contribute significantly to the development and progress of chemotherapy. Here we review some of the promising analog of targeting strategies that are under development for drug delivery. This review describes the preparation of polymeric micelles and the targeted modification which greatly enhance the effect of chemotherapy.关键词：Polymeric micelles;Drug-loaded;EPR effect;Active targeting
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发布时间：2022-09-18 - 摘要：Polyphenylene oxide, one of the five major universal engineering plastics in the world, was widely used in all walks of life. It has been more than half a century since polyphenylene ether was first synthesized. However, the synthesis mechanism of polyphenylene oxide was still not fully elucidated. In the paper, three possible mechanisms of the oxidative coupling in synthesizing polyphenylene oxide were introduced, including coupling mechanism of phenoxy radicals coordinated to catalyst complex, coupling mechanism of free phenoxy radicals and coupling mechanism of one-step two electron transfer. Of the three mechanism, coupling mechanism of one-step two electron transfer was generally accepted in the academic circles. Also, the chain extension mechanism including redistribution and rearrangement of quinine ketal intermediate was further elaborated.关键词：Synthesis mechanism;Two electron transfer;Quinine ketal intermediate
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发布时间：2022-09-18 - 摘要：Phenomenon of aggregation-induced emission(AIE), discovered in 2001, has been developed rapidly from early small molecules to polymer systems. Compared with traditional small molecules, polymer materials with AIE property can overcome the problems on processing and create favorable conditions for the preparation of highly efficient light-emitting devices. AIE mechanisms with the unchanged core of radiative transition channels caused by aggregation are developing with the discovery of AIE systems. The formation of each AIE phenomenon often requires the synergy of several factors. Continuous improvement of the mechanism on one hand help to explain the AIE phenomenon, on the other hand lay the theoretical foundation for the development of a new AIE system. This paper summarizes several polymer AIE systems which are formed on the basis of small molecules and introduces some relatively new AIE mechanisms based on the existing ones.关键词：Aggregation-induced emission(AIE);Fluorescence;Polymer;Mechanism
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发布时间：2022-09-18 - 摘要：Ultrahigh molecular weight polyethylene would become high performance fibers with high strength and high modulus by ultra-drawing. The temperature and draw ratio are significant spinning parameters. In this article, the effect of drawing temperature on the properties of UHMWPE fibers and the most appropriate temperature were systematically studied on with the help of tensile testing and DSC analysis. The results showed that the drawing temperature impacted on the maximum draw ratio, and ultimately affected the mechanical properties of fibers. In addition, the three draft allowed the mechanical properties of fibers to achieve a higher level, and the strength of the fiber was 32 cN·dtex-1 when the best temperature combination was 137.5℃-147.3℃-147.3℃.关键词：Ultrahigh molecular weight polyethylene fiber;High performance;High strength;High modulus;Drawing temperature
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发布时间：2022-09-18 - 摘要：The effect of the C/N mixed external donors on the crystallization behavior and the isotactic sequence distribution of polypropylene prepared by a MgCl2-supported TiCl4 Ziegler-Natta catalyst were studied through the SSA and 13C-NMR techniques. When the ratio of the mixed external donors/Ti (Si/Ti) is kept in a constant, the different relative amount of the mixed external donors has an important effect on the isotactic sequence length distribution of polypropylene. The SSA results show that the crystallization ability and the relative contents of highest isotactic component gradually increase with the rise of the relative component of Donor-C in the mixed external donors, and the thickness distribution of lamellar becomes broader, indicating the isotactic sequence length distribution of polypropylene gets broader. In addition, the 13C-NMR results show that the average isotactic sequence length and the average meso isotactic sequence length (MSL) of polypropylene gradually increase with the rise of the relative component of Donor-C in the mixed external donors, which shows a good correspondence between the SSA and 13C-NMR techniques.关键词：Polypropylene;Mixed external donors;SSA;13C-NMR;Isotactic sequence length
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发布时间：2022-09-18 - 摘要：Poly(N,N-dimethylacrylamide-co-acrylamide)hydrogel was prepared by aqueous solution polymerization in redox initiator system,and α-amylase was immobilized by this hydrogel. Effects of the amount of crosslinking agent and initiator, monomer concentration, as well as monomer ratio on the characteristic of hydrogel were studied. Maximum equilibrium swelling ratio as the index obtaine the optimizing condition of preparing Poly(N,N-dimethylacrylamide-co-acrylamide) hydrogel: the amount of crosslinking agent is 0.3%, the amount of initiator is 0.6%, monomer concentration is 20% and n(DMAA):n(AM) is 2:1.With this condition immobilize α-amylase in situ polymerization and study the activity of immobilized enzyme.关键词：Hydrogel;Equilibrium swelling;α-Amylase;Immobilized α-amylase
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发布时间：2022-09-18 - 摘要：Isoprene rubber without antioxidant was carried out in 150℃ for the thermal oxygen aging. Molecular weight, molecular weight distribution and changes of chemical structure have been investigated by GPC and 1H-NMR. It is shows that degradation reaction of isoprene rubber happened but no significant chemical structure changed at the beginning of ageing,but molecular weight decreased gradually, molecular weight distribution becomes wider. However, in later stage, crosslinking reaction happened, but the extent of the crosslinking reaction is lower than the degradation reaction, and aldehydes, carboxylic acid, olefin and alchole were generated. Thermogravimetric kinetics to isoprene rubbers without antioxidant has been investigated by TG under N2. It suggested that with the increase of proportion of weightlessness, the activation energy increased.关键词：Isoprene rubber;Thermal oxygen aging;Chemical structure;Thermogravimetric kinetics
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发布时间：2022-09-18 - 摘要：With 3-chloro-1,2-epoxypropane,cyanuric acid and piece of alkali as raw material to produce triglycidyl lsocyanurate (i.e. TGIC), the production process have two step synthesis: in the role of catalyst, 3-chloro-1,2-epoxypropane happened open-loop reaction with cyanuric acid.Then happened closed-loop reaction to produce TGIC during joining in the piece of alkalito.And after the suction filtering, distillation, refining, granulation could get the production of TGIC.关键词：TGIC;Ring agent;3-Chloro-1;2-epoxypropane;Open-loop reaction
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发布时间：2022-09-18 - 摘要：Xanthan gum is a biological polysaccharide with great development potential, which plays important role of thicking, emulsifying, stabilizing owing to the unique molecular structure and has been widely used in daily chemical industry, petroleum exploitation, textile printing and dyeing, food, pharmaceuticals, coating, pesticide and other industry fields. This article summarized the structure, characteristics and production technology and main application areas of xanthan gum, introduced the application research status about using xanthan gum in pesticide formulation processing, and pointed out that the superior rheological properties of xanthan gum was of great significance to the improvement of suspension stability of pesticide formulations such as suspension concentrate, emulsion in water, suspo-emulsion, finally looked into the future prospects for the development of xanthan gum.关键词：Xanthan gum;Pesticide formulation processing;Applications
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发布时间：2022-09-18 - 摘要：Porogen leaching method is most commonly used for fabricating micro- and macro-porous polymer scaffolds. The advantage of this method is that the process is easy to carry out and easy to control the pore size and porosity by selecting suitable particle size and amount of the added salt particles. However, most of the scaffolds prepared by this method are limited to two-dimensional films with 2~3mm, and the scaffolds usually have a poor interconnectivity between macropores. Moreover,the porogen and solvent can remain in polymer scaffolds. The development situation of modified porogen leaching method is reviewed in this paper, and the effects and deficiencies of the modification are discussed.关键词：Porogen leaching;Porous scaffold;Tissue engineering
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发布时间：2022-09-18 - 摘要：《Polymer Chemistry》course is the required course for the most materials type specialty. The learning interest of students and the mastery extent on this course are very important for the learning of succedent professional course. Contraposing the common problems in the teaching of 《Polymer Chemistry》course, such as the key points and teaching arrange, main line and aims, essence of controllable/"living" radical polymerization and its meaning for the development of polymer science, connotation of coordination polymerization and its teaching key points, relationship of classical polymer chemistry and new development in the area of polymer chemistry, the own viewpoints were advanced. And the teaching experience and method to arouse the learning enthusiasm of students and enhance teaching quality were discussed.关键词：Polymer chemistry;Teaching;Realization
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发布时间：2022-09-18 - 摘要：A new understanding about the knowledge system of polymer physics was proposed here: the behavior of a polymer was the reflection of the change or movement of variety of structures ranging from atoms to the whole bulk of polymer. A comprehensive classification of polymer structure is necessary to explan the change as well as the behavior of polymer.关键词：Polymer physics;Knowledge system;Structure;Teaching research
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发布时间：2022-09-18
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