最新刊期
卷 33 ， 期 10 ， 2020
- 摘要：As a class of high-performance polymers, imide-based porous polymer materials were widely used in many areas such as aerospace, microelectronics, membrane materials, optoelectronic materials, catalysis, biomedicine, sensors, gas storage and seperation. Among them, porous polymers containing imide subunits have attracted much attention in recent years, especially the crystalline porous polyimides. Different from conventional synthesis of porous polyimide by the imidation reaction between aromatic polyamines and polyanhydrides, this review reported the recent progress on the construction of imide-based porous polymer materials via the polymerization on imide monomers, including ring-opening metathesis polymerization, free radical polymerization, aromatic nucleophilic substitution polymerization, metal-catalyzed polymerization and so on. In addition, the post-functionalization on polyimides also provided good opportunity to enhance the diversity of porous polyimides, such as thermal-initiated crosslinking of polyimides, Diels-Alder reaction on polyimides and so on. In summary, the traditional polyimides materials have found new applications by incorporating the novel structures to porous polyimides, especially via the polymerization on imide monomers. The rational design of well-defined porous polyimides with novel structure will catch more attention in the near future. The synthetic polymer chemistry will play more important roles in building up the functionalized porous polyimides materials. All these will contribute to the new development era of polyimides materials in the near future.关键词：Porous polyimide;Porous organic polymer;ROMP;Free radical polymerization;Pre-functionalization strategy
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发布时间：2022-08-31 - 摘要：Nanocellulose (NC) is a new type of nanomaterials with unique structure, excellent mechanical properties, light weight, high specific surface area, renewable, and biodegradable properties. The characteristics and main preparation methods for the three types of nanocellulose, including cellulose nanocrystal (CNC), cellulose nanofibers (CNF), and bacterial nanocellulose (BC), were discussed. At the same time, we introduce recent advances of NC derived materials in the field of electrochemistry, including supercapacitors, lithium-ion batteries, sensor, lithium-sulfur batteries, and sodiumion batteries.The application prospect of new nanocomposites with NC as the main component is prospected.关键词：Nanocellulose;Supercapacitor;Lithium-ion battery;Sensor
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发布时间：2022-08-31 - 摘要：Nano carriers, due to the enhanced osmotic blockade (EPR) effect, can highly enrich in the tumor site, which is conducive to enhancing the internal circulation time and drug stability, and thus become a powerful means to enhance the therapeutic and diagnostic effect of tumor. As a natural biological macromolecule, polysaccharide has good biocompatibility and biological function, which can achieve active targeting. For example, hyaluronic acid has the function of specific targeting to CD44 receptor. Therefore, the nano carrier prepared from polysaccharide is one of the excellent candidate materials for anticancer drug encapsulation and targeted controlled release. At present, dextran, chitosan, hyaluronic acid, alginate and other polysaccharides have been successfully used in the preparation of polysaccharide nano carriers and related biomedical applications. Among the different methods of preparing polysaccharide nano carriers, including emulsification and self-assembly, self-assembly has become the main way of preparing polysaccharide nano carriers because of its wide application and controllable performance. The self-assembly of polysaccharide nano carriers mainly includes polyelectrolyte adsorption self-assembly, two-step self-assembly based on polysaccharide polymer, and onestep polymerization/self-assembly. At present, the preparation of polysaccharide nano carriers is mainly through two steps: first, the modification of polysaccharide or the synthesis of polysaccharide copolymers, and then the self-assembly of polysaccharide copolymers induced by different driving forces. However, the complex modification methods of polysaccharides and the low solid content in the self-assembly of polysaccharide solution result in the low aging rate of the two-step preparation of polysaccharide nano carriers, which is difficult to meet the needs of practical application. In recent years, some research groups including us have proposed the "one-step "preparation of polysaccharide nano carriers by the" polymerization self-assembly" two in one way. From the point of view of polysaccharides, in the process of grafting copolymerization of monomers on the main chain of polysaccharides, the solution phase self-assembly of the copolymers is driven, and then the nano carrier of polysaccharide group is prepared in one step. In the "one-step" approach, the preparation efficiency of nano carriers can be significantly improved, and the nano carriers can be given specific functionality by introducing appropriate functional monomers. This approach provides a new way for the preparation of polysaccharide nano carriers. In this paper, the self-assembly methods for the preparation of polysaccharide nano carriers are introduced. Based on the induction of the driving force for the preparation of polysaccharide nano carriers by "two-step" method, the " one-step" method for the self-assembly induced by graft copolymerization is emphasized. In addition, based on the special biological functions of polysaccharides, such as cell recognition, this paper also introduces the active target drug transport and other biological applications of polysaccharide nano carriers, in order to provide reference for the efficient preparation of polysaccharide nano carriers with biological functions.关键词：Polysaccharide nanocarrier;Self-assembly approach;Two-step method;One-step method;Active targeting
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发布时间：2022-08-31 - 摘要：With the development of coated fertilizers and its coated materials, the environmental response coated fertilizers have attracted extensive attention of researchers in order to meet the needs of more agricultural production environments. With the characteristics of intelligent response and slow and controlled release, the environmental responsive coated fertilizers can respond to specific stimulation signals such as pH, temperature, light and magnetic field in the fertilization environment, so as to change the physical or chemical structure of coated materials, and control the release rate of fertilizer nutrients. Therefore, the research and development of environmental responsive fertilizers has certain practical significance. Based on the practical application of fertilizers, this article reviews the preparation and effects of pH responsive coated fertilizers, temperature responsive coated fertilizers and magnetic responsive coated fertilizers.关键词：Environment response;pH;Temperature;Magnetic induction;Coated fertilizers
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发布时间：2022-08-31 - 摘要：Because of their good biocompatibility, gelatin-based adhesives are widely used in the field of tissue engineering, but their adhesive ability still needs to be improved. In this paper, the oxidized dextran and gelatin formed one cross-linking network through Schiff base reaction, while enzymatic cross-linking reaction between transglutaminase and gelatin formed another cross-linking network. The formation of the double cross-linking network can enhance the bulk strength of gelatin adhesive. The properties of the adhesive were characterized by vial inversion, swelling, compression, lap shear, etc. The modified gelatin-based adhesive’s gelation time was suitable for injection, and the obtained gel showed a lower swelling ratio. The adhesive’s compression modulus was up to 33.6kPa, which is 4 times that of unmodified gelatin. And the bonding strength of adhesive was up to 25.9kPa, it is 12 times that of unmodified gelatin. The performance of gelatin-based adhesives has been improved.关键词：Gelatin;Hydrogel adhesive;Transglutaminase;Oxidized dextran;Double crosslinked network
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发布时间：2022-08-31 - 摘要：A kind of naphthalenesulfonic acid type sulfonated polysulfones was obtained by post-sulfonation method with polysulfones as basic materials. After characterizing their chemical structure by FT-IR and 1H-NMR spectrum. The corresponding proton exchange membranes(PEMs) were fabricated by solution casting method. The effect of temperature on properties of sulfonated polysulfones PEMs including water uptake, swelling ration and proton conductivity was mainly explored. The result show that the water uptake, swelling ratio and proton conductivity of sulfonated polysulfones PEMs increased with the addition of temperature because the movement ability of sulfonic acid group at the end of side chain enhanced. Compared with sulfonated aromatic polymers PEMs, the APS-NS PEMs shows excellent dimensional stability at high water sorption since the APS-NS could form obvious phase-separation structure by locating the sulfonic acid group far away from main chains of polysulfone. The water uptake of APS-NS-4 PEMs whose bonding amount of sulfonic group 1.55mmol/g were up to 29.2% at 25℃ and 42.8% at 85℃, but the corresponding swelling ratio were only 23.6% at 25℃ and 53.3% at 85℃, much lower than Nafion115 PEM at the same condition. The proton conductivity of APS-NS-4 PEMs was up to 0.084 S/cm at 25℃, meeting the practical requirement of proton exchange membrane fuel cells for PEMs.关键词：Polysulfones;Naphthalenesulfonic acid;Water uptake;Proton conductivity;Dimensional stability
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发布时间：2022-08-31 - 摘要：In this paper, g-C3N4 was prepared by calcining melamine at high temperature, and g-C3N4/AOCF monolithic composite catalytic material was prepared with amidoxime fiber as carrier and water bath method, which is cheap, easy to get, high catalytic activity, non-toxic, harmless and easy to recover. The samples were characterized by XRD, SEM, FT-IR, XPS, UV-Vis DRS, etc. the SEM results showed that g-C3N4 was uniformly distributed on the surface of the fiber, showing an amorphous morphology. The XPS and FT-IR results confirmed that there was a certain chemical bond between g-C3N4 and aocf. Under UV irradiation, the catalytic activity of the catalytic material was investigated by degradation of Rhodamine B dye. The results showed that when the addition of g-C3N4 was 3 g/L, the reaction was carried out at 30℃ in water bath The g-C3N4/AOCF composite catalyst prepared by H has the best photocatalytic activity. The repeatability experiment shows that the catalyst has good stability and the photocatalytic reaction process conforms to the first-order reaction kinetics.关键词：g-C3N4/Amidoxime fiber;High temperature calcination-water bath method;Photocatalytic degradation;Rhodamine B
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发布时间：2022-08-31 - 摘要：The Glass Transition Temperature (Tg) of amorphous Polystyrene (PS) was systematically studied by differential scanning calorimetry (DSC) and Molecular Dynamics simulation with the COMPASS II force field, which is more consistent with the experimental data. It was found that the average Tg values remained unchanged after the model size reaches 38.6Å by studying the models of different size cells. The simulated Tg values increased with the increase of the polymerization degree. And the increasing trend was almost consistent with the trend of increasing the Tg values of the DSC test, which demonstrated validation of the force field on Tg study of Molecular Dynamics simulations for PS. Through gradually lowering the rate of temperature rise, the model with 50 degree of polymerization and 4 chains can accurately simulate the testing Tg value of PS, 351K. Additionally, the glass transition point of the model during the temperature rise and fall process is reproducible.关键词：Molecular dynamics;Polystyrene;Glass transition temperature;DSC
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发布时间：2022-08-31 - 摘要：In view of the shortage of innovative talents training in practical teaching of polymer materials and engineering, investigation of practical teaching model based on the integration of "Micro-challenge Cup" and practical teaching was carried creatively, after researching the model of practical small-project courses for undergraduates of Aalborg University in Denmark. The new model aims at cultivating students' innovation ability, takes the new practical teaching concept as the guidance, takes the practical teaching activities as the main content, and takes the corresponding environmental resources as the guarantee condition. The application of the new model in the practical teaching of polymer materials and engineering realizes the organic combination of professional education and innovative education, solves the problems of generality and individuality in the practical teaching, forms the characteristics of professional practical teaching, and is beneficial to the cultivation of innovative talents in professional application.关键词：Innovative talents;Practical teaching;Innovation education
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发布时间：2022-08-31 - 摘要：Comprehensive and innovative practice plays an important role in cultivating talents with comprehensive engineering ability. In this paper, the structure and performance analysis of modified nano SiO2 and its effect on the performance of natural rubber (NR) were designed according to the requirements of comprehensive and innovative practice. By contacting and summarizing the knowledge of basic courses and professional courses, students searched literature, understood the experimental connotation and designed a feasible experimental scheme, and the modification effect of different coupling agents and their influence on the properties of NR were systematically analyzed. Through the implementation of comprehensive and innovative practice, it can enable students to cross and systematically integrate knowledge points of many courses for polymer material major, and the students' experimental skills and ability to solve complex engineering problems were improved by mutual assistance.关键词：Professional certification;Comprehensive and innovative practice;Nano SiO2;Natural rubber
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发布时间：2022-08-31 - 摘要：Polymer chemistry is a core course of the major of polymer materials and engineering in our university. Polymer chemistry experiment is an experimental course established on the basis of polymer chemistry course. The teaching content of polymer chemistry course determines that polymer chemistry experiment is mainly composed of synthetic experiment. Based on the design of experimental teaching content and the actual teaching situation in our university, this paper analyzes the necessity of realizing the green teaching of polymer chemistry experiment in detail, and summarizes the concrete measures and methods of realizing the green teaching. Using these measures and methods, on the premise of achieving the required teaching effect, the harm caused by synthetic experiment to teachers and students' bodies is minimized, and the pollution caused to the environment is reduced.关键词：Green chemistry;Environmental protection;Polymer chemistry;Experimental teaching
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发布时间：2022-08-31 - 摘要：The curriculum of Rubber Forming and Processing is a core curriculum for polymer material processing technology specialty. Incorporating innovation and entrepreneurship education into the curriculum teaching has a very important role in training talents with innovative and entrepreneurial capabilities. Driven by the integration of production and education, the curriculum deepens the cooperation between schools and enterprises and collaborates in educating students. This paper summarizes from the following aspects: establishing a dual-teaching teaching team, constructing the curriculum system, integrating the curriculum content, reforming the teaching methods, and the evaluating methods,etc. The practice and experience of integrating innovation and entrepreneurship education into couse teaching reform is also introduced. The practice has proved that taking typical work tasks of enterprises as the project teaching content, and integrating school-enterprise cooperation research projects into curriculum teaching, can effectively achieved the effective combination of innovation and entrepreneurship education and professional curriculum education, and has achieved remarkable results in talent cultivation.关键词：Innovation and entrepreneurship;Rubber Forming and Processing;Curriculum reformation
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发布时间：2022-08-31
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