最新刊期
卷 32 ， 期 5 ， 2019
- 摘要：Bacterial cellulose nano-fiber is a kind of natural nano material with excellent biocompatibility and mechanical properties. It also has the advantages of high purity,high degree of polymerization, high crystallinity,good water holding capacity and large aspect ratio. A variety of methods can be used to combine bacterial cellulose nano-fiber and polymers. The key challenge is how to modify it to improve the interfacial compatibility of nano-fiber and polymer and the uniformity of nano-fiber in polymer, thereby improving the properties of composites and expanding its applications. In this paper, the latest research progress on the modification of bacterial cellulose nano-fiber and their composites are briefly reviewed, including modification mechanisms, preparation methods, performance characteristics and potential applications.关键词：Bacterial cellulose;Nano-fiber;Nanocomposites;Modification;Preparation methods;Performance
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发布时间：2022-09-02 - 摘要：This paper first introduces the structure and properties of carbon nanotubes, and then points out the advantages and disadvantages of carbon nanotubes. Carbon nanotubes, as a novel one-dimensional nanomaterial of carbon structure, have excellent optical,electrical, mechanical and thermal properties. However, the surface of the carbon nanotube lacks active groups, poor dispersion, and is difficult to process, which limits its application. Then the types and properties of aramid fiber are introduced, and the mechanism of modification of carbon nanotubes by aramid fiber is introduced. Three physical methods and a chemical method for modifying carbon nanotubes by aramid fiber are reviewed. The performance of the new materials obtained was also analyzed. Finally,the development of fiber and carbon nanotube composites is prospected.关键词：Carbon nanotubes;Aramid fiber;Modification
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发布时间：2022-09-02 - 摘要：Benzophenone photoinitiators are the simplest hydrogen abstraction type photoinitiators with simple structure. They are the cheapest photoinitiators. However, it has the disadvantages of low activity, slow photocuring rate and easy yellowing. In order to solve the shortcomings of benzophenone itself and give full play to its advantages, scientists have developed novel and mature benzophenone photoinitiators for varieties and their properties. This article will introduce the new benzophenone macromolecular photoinitiators, polymerizable photoinitiators, aqueous photoinitiators, and hybrid photoinitiators developed by scientists in recent years, and review their research progress and application value in various fields.关键词：Photocurable coating;Photoinitiator;Benzophenone
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发布时间：2022-09-02 - 摘要：Hyperbranched organic silicon usually have three dimensional structure and no chain entanglement between molecules and molecules,making them exhibit low viscosity,high reactivity,high solubility and so on. Hyperbranched organic silicon has wide-range prospect in the field of functional polymers due to its simple procedures, lower cost as well as scale production and functionalization. The paper reviews the preparation of the functional polymer of hyperbranched organic silicon including the hyperbranched polysiloxane,polycarbosilane,polysilane as well as the organic silicon of hyperbranched with heteroatom. It concludes the implementation of the functional polymer of hyperbranched organic silicon in areas,such as the catalyst carrier, biomedical materials,heat-resistant material,ceramic precursor and photoelectric material, and provides an outlook of the future of the functional polymer of hyperbranched organic silicon.关键词：Hyperbranched;Organic silicon;Functional polymer;Polysiloxane;Polycarbosilane;Polysilane
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发布时间：2022-09-02 - 摘要：Poly 1-butene (PB-1) has good applications in film, sheet, pipes,sealant and so on because of its outstanding properties such as creep resistance,heat resistance,grinding resistance,environment stress crack resistance.,therefore,it is honored as the "golden plastic", However, compared with other polyolefin materials, the cost of PB-1 is higher and the crystalline transition rate is very slow. It need to let stand at room temperature for 7 ~10 days to complete from thermodynamic unstable crystal form Ⅱ crystal to thermodynamic stable crystal form I morphology transformation,this will increase the difficulty of processing. In recent years, researchers have been trying to make physical modification of PB-1 and have made some achievements in order to reduce the production cost of PB-1 and improve its performance. In this paper, the development progress of poly(1-butene) (PB-1) physical modification was introduced. The blending modification and filling modification are introduced,and the development prospect of PB-1 is prospected.关键词：Poly(1-butene);Physical modification;Blending modification;Filing modification
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发布时间：2022-09-02 - 摘要：Chitosan is a kind of new low cost and environmental friendly natural polymer material,which has no toxicity, biocompatibility and biodegradability, so it has better application prospect in water treatment field. However,the chitosan has the disadvantages of acid solubility, low mechanical strength, limited number of functional groups, poor water treatment effect,etc.,chitosan generally needs to be modified. In this paper, the latest research progress of cross-linking and grafting in chitosan chemical modification is introduced. Crosslinking can improve the acid solubility of chitosan,the commonly used crosslinked agents include glutaraldehyde, epichlorohydrin, ethylene glycol diglycidyl ether, tripolyphosphate, etc. The graft methods can be used for the poor treatment of chitosan. The functional groups of grafting include amino group, carboxyl group, alkyl group, etc., but the number of functional groups of grafted small monomers is limited,polymer grafting can be used to improve the performance of water treatment. Polymer grafting is a relatively new, low cost,modification method that can introduce a large number of functional groups and has a broad research perspective.关键词：Chitosan;Modification;Cross-linking;Grafting;Glutaraldehyde;Polymer grafting
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发布时间：2022-09-02 - 摘要：Thin photo-thermal sensitive hydrogel film on elastic substrate has been widely used in the fields of micromechanics system (MEMS), biosensors and actuators. Due to the confinement of the elastic substrate, when the photo-thermally sensitive hydrogel swelling with the change of external temperature or light intensity, the existence of the compressive stress in the hydrogel film makes the film wrinkle. Based on the finite deformation theory of the photo-thermally sensitive hydrogel and von Karman nonlinear plate theory, this paper studied the wrinkling mechanism of the photo-thermally sensitive hydrogel film and analyzed the effects of light intensity, temperature, chemical potential of the solvent and the stiffness coefficient of the substrate on the critical wavelength and critical stress of wrinkling of photo-thermally sensitive hydrogel film. The results show that: when the temperature and light intensity keep the same,the critical stress decreases with increasing chemical potential of the solution; when the chemical potential keeps the same, the higher the light intensity and temperature, the greater the critical stress; when the light intensity and the temperature keep the same,the smaller the stiffness coefficient, the greater the critical wavelength; for the same stiffness coefficient, the lower light intensity and the temperature, the smaller the critical wavelength.关键词：Photo-thermal sensitive hydrogel;Film-substrate structure;Wrinkling;Critical wavelength;Critical stress
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发布时间：2022-09-02 - 摘要：Graphene has a unique structure and excellent properties. The performance of the polymer can be greatly improved by adding only a small amount of graphene. The crystallographic forms and non-isothermal crystallization kinetics of polyamide 6(PA6)and polyamide 6/Amino graphene(PA6/AG) composite were investigated by X-ray diffraction(XRD)and differential scanning calorimetry(DSC).The results show that,the addition of AG couldn't lead to a distinct change to crystallographic form of PA6.The Avrami equation could successfully discribe the isothermal cryatallization behavior of PA6 and PA6/AG composite.AG in PA6/AG composite could serve as effective heterogeneous nucleating agent,which made the crystallization temperature increased and crystallization rate accelerated.关键词：In situ polymerization;Polyamide 6;Amino graphene;Non-isothermal crystallization
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发布时间：2022-09-02 - 摘要：Molecularly imprinted polymer was prepared by reversible addition fragmentation chain transfer polymerization with diniconol as template molecule. The results showed that the maximum adsorption capacity of the imprinted polymer was 39.3mg/g, the maximum adsorption capacity of non-imprinted polymers is 14.5mg/g. The adsorption performance was studied and its morphology was characterized by electron microscopy. The results showed that Imprinted Polymer uniform particle size and good dispersibility. It was used as a solid phase extraction filler and combined with high performance liquid chromatography to analyze the residual diniconazole in apples. Under optimized conditions,the detection limit of diniconazole was 1.64×10-3 mg/kg; the recovery was 93.2~100.3%. The column could enrich and purify the diniconazole with better effect than the common C18 column.关键词：Molecular imprinting;Diniconazole;Solid phase extraction;High performance liquid chromatography
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发布时间：2022-09-02 - 摘要：With the guidance of the competency-based training of engineering education accreditation,a set of innovative and comprehensive experiments, which was named the fabrication of poly (lactic acid)/ferriferous oxide (PLA/Fe3O4)nanocomposites and its microwave-assisted foaming ability, were proposed. On the bases of students' understanding of the topic, consulting the literature and preparing the essential principles, the optimized experimental routes were drawn properly. The PLA/Fe3O4 nanocomposites characterized by uniform dispersed particles and well-bonded interfaces were fabricated successfully, and then investigations on interface structure, molecular weight as well as microwave-assisted foamability of the composites were carried out. To promote the subjective activity of students participating in the experimental courses, a novel evaluation system, which is combined by process management and result assessment and concerning every step of the whole experiments, has been established. On the other hand, the proper corrective actions could also be made according to feedback from the students, finally improving the qualities of experimental teaching and achieving the expected training targets.关键词：Competence oriented;Experimental teaching;Poly (lactic acid);In-situ polymerization;Microwave-assisted foaming
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发布时间：2022-09-02 - 摘要：The molecular weight and molecular weight distribution of polymers is one of the important parameters affecting the properties of polymers, so it is an important knowledge point in Polymer Physics. Analogy teaching method which takes this knowledge point as the example is used in the teaching experience. Firstly, the students are guided to comprehensively grasp the characterization methods and principles of molecular weight and molecular weight distribution of polymers by the method of summarizing to "give one". Then three examples are carefully prepared from easy to difficult, which are resolved correctly by comparison, analogy, and association of the summarized knowledge points. Through the training,the analogical thinking and flexible using ability of students are trained,so the purpose of training is achieved. In order to further deepen students' understanding of knowledge points,students are required to adopt the "anti-three" mode in the homework. There are many types of highly quality questions proposed by students self-questioning and self-answering. It is shown from the students' homework that the teaching method proves a good effect.关键词：Analogy teaching method;Polymer Physics;Analogical thinking ability
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发布时间：2022-09-02
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