最新刊期
卷 31 ， 期 9 ， 2018
- 摘要：With the continuous development of high performance computers, numerical simulation is used to study the relationship amongst screw geometry,operating parameters and material parameters in the process of reactive extrusion. It has important guiding significance for the synthesis,processing and modification of polymers. However, due to the complexity of reactive extrusion process and the strong coupling among high shear melt flow, heat transfer, and complex rheological properties,accurate numerical simulation is very difficult. The mathematical and physical models used in numerical simulation at the present stage are summarized. They can be divided into one-dimensional reactor model and computational fluid dynamics model. The development of numerical simulation of reactive extrusion process is mainly based on CFD method. The transfer and polymerization kinetics are strictly coupled,and the multi-phase transfer process is considered. By optimizing the algorithm,reactive extrusion processes for polymerization can be accurately predicted.关键词：Polymerization;Reactive extrusion;Numerical simulation;Kinetics;Computational fluid dynamics
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发布时间：2022-09-05 - 摘要：Aerogels is a type of intriguing material prepared by replacing the liquid solvent in a gel with air without substantially altering the network structure or the volume of the gel body. These materials have porous structure with high porosity,low-density, high specific surface area,low dielectric permittivity and extraordinarily low thermal conductivity. Cellulose as a biodegradable polysaccharide is the most abundant biopolymer on plants. Cellulose has gainedinteresting research because it safe, stable,nontoxic,biodegradable,renewable,low cost. Cellulose aerogel as the new generation of materials promise not only a very low density as typical for aerogels but also a comparatively high strength and ductility compared with inorganic or polymeric aerogels. This paper introduced the preparation and drying technologies of cellulose aerogels. More applicationsare evolving as the scientific and engineering community becomes familiar with the unusual and exceptional physicalproperties of cellulose aerogels,focusing on catalysis,electromagnetism, heat insulation, biomedical application and purification. Moreover,the current problems and future development about cellulose-based aerogel were also mentioned.关键词：Cellulose;Aerogels;Construction;Functionalization
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发布时间：2022-09-05 - 摘要：Developing the natural gas resources in the deep sea is an important means for the advancement of clean energy. However, formation of natural gas hydrate brings serious challenges to the drilling operations. Hydrate kinetic inhibitor is a kind of polymer compound which can solve the problem of pipeline blockage. Molecular dynamics (MD) simulation can provide a good theoretical guide for studies of hydrate inhibitors. This paper reviewed the methods of evaluating performance of the inhibitors by using MD in recent years,analyzed possible inhibition modes and mechanism, and studied the factors of the effect of inhibitors and developing of new inhibitors. The prospects for the MD simulation research in the field of gas hydrate inhibitors are also put forward.关键词：Energy polymers;Gas hydrate;Molecular dynamics;Inhibitors;Inhibition mechanism
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发布时间：2022-09-05 - 摘要：Light microspheres have attracted lots of attention of researchers recently,because of high specific surface areas, high loads, excellent stability, high surface permeability and low density. This review focuses on the recent progress of light microspheres including hollow microspheres,and porous microspheres, introduces several new synthesis methods, such as seed swelling polymerization,suspension polymerization,template method,LBL assembly,surface-molecular imprinting method and liquid-liquid phase separation technique,summarizes the applications,including biomedical, wastewater treatment, coating,biosensor and electronic information fields,and give an outlook of some future research directions,including control of inner cavity structures of hollow microspheres,modulation of particular pore structure of porous microspheres and so on.关键词：Light microspheres;Hollow microspheres;Porous microspheres;Template method;LBL assembly
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发布时间：2022-09-05 - 摘要：According to the excellent thermal stability of silicone rubber,it is expected to be applied in the aerospace field,but its application is limited due to its own poor mechanical properties. The application of graphene modified silicone rubber with excellent mechanical properties,electrical properties and thermal stability is reviewed in this paper. The four preparation methods of graphene modified silicone rubber composites were introduced,they are emulsion blending method, solution blending method,melt blending method and mechanical blending method,and emphatically summarized the mechanical blending method. The effects of graphene modified silicone rubber composites and their research status were compared and analyzed,and it was concluded that domestic and international researches of graphene modified silicone rubber are mainly focused on the electrical properties of silicone rubber. Finally,the application of graphene modified silicone rubber composites is also prospected.关键词：Graphene;Silicone Rubber;Composite;Research status
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发布时间：2022-09-05 - 摘要：Nanocapsule technology is a very prospect emerging technology,which have its own uniqueness and superiority in different fields. summarize domestic and foreign literature review of nanocapsule technology in plant essential oils in recent years. Nano-microcapsule technology transforms liquid plant oils to solid and effectively controls aromatic plant oil to slow release propertie to extend the fragrant time. it's widely used in food,cosmetics and textiles industries. The application of nanocapsule technology in plant essential oils shows that plant essential oils have great potential market value. However,a great deal of work needs to be devoted to the research of new preparation methods of plant essential oil nanocapsules,and a complete and practical system is established to evaluate the properties of nanocapsules. The purpose of this study is to find low price environmental friendly and non-toxic wall materials to obtain more application value of nanocapsule material.关键词：Nanocapsule;Plant essential oil;Preparation;Application
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发布时间：2022-09-05 - 摘要：The chemically modified hyaluronic acid not only retains good biocompatibility and biodegradability, but also obtains unique properties, such as anti-degradation,viscoelasticity and so on. Using this property, cross-linked hyaluronic acid can be used for vascular embolization. In this study,The microspheres was prepared by emulsion cross-linking technique. The effect of the initial reaction concentration,emulsifying shearing speed and the ratio of oil and water on pellet formation and size distribution was investigated,light microscope were used to observe the microspheres,the physical and chemical properties of the microscope were studied. The results show that the surface of the microspheres is smooth, the shape of the spheres is complete,and the microspheres have good compressive deformation resistance. It meets the requirements of microsphere embolization and provides the theoretical basis for the experimental study in vivo.关键词：Hyaluronic acid;Microspheres;Embolization
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发布时间：2022-09-05 - 摘要：A new acylhydrazone bond gel (AB-gel ) using 1,3,5-benzenetricarbohydrazide and 4,4'- biphenyldicarboxaldehyde as organic monomers was well designed and successfully synthesized based on the principle of Schiff-base reaction and the covalent bond as cross-linking point. The synthetic method of AB-gel has the characteristics of simple, mild condition,no catalyst,fast reaction rate and high yield. The structure and properties of the materials were characterized by infrared spectroscopy,13C solid state NMR,scanning electron microscopy,X-ray powder diffraction and thermogravimetric analysis. The results show that the AB-gel material has uniform nanoparticle size,porous three- dimensional net-work structure and excellent physical and chemical properties.关键词：Schiff-base reaction;Acylhydrazone bond;Polymer gel;Preparation;Characterization
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发布时间：2022-09-05 - 摘要：In order to improve the toughness of polyoxymethylene (POM), two elastomers, namely thermoplastic polyurethane (TPU) and polyolefin elastomer (POE, ethylene-octane copolymer),were blended. The influence of crystallization behavior and microstructure evolution on the mechanical properties of pure POM, POM/TPU (85/15) and POM/POE (85/15) blends were examined. Large size spherulites of pure POM was found under polarizing microscope and a large number of micron-scale voids exist on the fracture surface of pure POM, which might be the main contribution to its poor notch impact strength. The voids as the defects of the material tend to form at the edge of the spherulites during the cooling or at the late stage of isothermal crystallization. Blending of the elastomers could significantly accelerate the crystallization rate of POM while reducing the size of the spherulites, which will reduce the number of voids and thus improve the toughness. For POM/TPU 85/15 blend,good compatibility between the two components and the large number of fine crystals coherently determine its significantly improved toughness and better tensile strength. While the poor compatibility between POM and POE with the interface restricted spherulite morphology make it exhibits discounted mechanical properties.关键词：Polyoxymethylene;Elastomers;Toughening;Crystallization behavior;Mechanical properties
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发布时间：2022-09-05 - 摘要：Hybrid teaching model,combining the complementary advantages of traditional teaching and network teaching,is an important aspect of research in teaching reform in universities currently. In this article,the blended teaching model was used in the teaching of chapter II in the course " polymer materials processing technology". During learning "basic theory of polymer materials processing",the teaching methods and content of classroom discussions were redesigned. Finally,the application effects of the designed teaching model were verified and analyzed by surveying the students taking the course. The higher grades were found from the evaluation results occurred to the hybrid teaching model, which indicated the students can get through to the critical knowledge point by hybrid teaching model.关键词：Hybrid teaching model;Teaching reform;Polymer materials processing technology
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发布时间：2022-09-05 - 摘要：As the engineering education accreditation work is comprehensively carried out in China's colleges and universities,we conducted a series of teaching reforms in the course 'Fundamentals of material science and engineering' for polymer materials and engineering major based on the core concepts of engineering education accreditation. The reform exploration of curriculum contents,teaching ideas, teaching methods and evaluation mode was introduced,and the continuous quality improvement of student-centered-outcome-based teaching mode was discussed.关键词：Engineering education accreditation;Fundamentals of material science and engineering;Student-centered;Outcome-based Education;Continuous quality improvement
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发布时间：2022-09-05 - 摘要：The curriculum of Technology of processing rubber"contains the raw materials, formulate design and process technology,it is one of the curriculums for the undergarduate students majoring on polymeric materials and engineering and composites materials engineering. According to the problems in the teaching,some specific reform ideas were provided, such as according to the teaching outline, highlighting key knowledge, using interactive teaching, guiding students to think independently, and combining theory with practice through project teaching. Through the feedback of students after class and the feedback from the employers of rubber industry on the comprehensive performance of the employment students, the reform can effectively improve the teaching effect and the comprehensive quality of students.关键词：Rubber process;Course;Reform
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发布时间：2022-09-05
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