最新刊期
卷 34 ， 期 3 ， 2021
- 摘要：Integrated rubber is a new product of rubber, it is mainly used to prepare the tread compound of highperformance tire, because of its characteristics of safety, high performance, long life and economy, it is also an ideal material for preparing green tires. The synthesis of integrated rubber is the frontier project in the field of macromolecular design, anionic polymerization has been successfully used to control the configuration and sequence distribution of the structure unit of integrated rubber. This paper introduces the characteristics, classification and preparation methods, technology research status, industrial background and raw material market status of integrated rubber styrene-isoprenebutadiene terpolymer (SIBR). Combining with the existing research foundation and market situation in China, this paper points out the prospect of its development and utilization in China, and puts forward some suggestions and guidance for its future development.关键词：Integrated rubber;Preparation technology;Research status;Background analysis;Prospect forecast
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发布时间：2022-08-30 - 摘要：Self-healing hydrogels achieve crack closure by reconnecting broken links in the hydrogel matrix. Self-healing hydrogels could restore their original structure and function after physical injury. It has multiple characteristics, such as injectability, conductivity, adhesion. In recent years, more and more attention has been paid. Self-healing hydrogels have been widely used in pharmaceutical engineering, biomedical and other fields. However, the compatibility of its toughness and rapid healing remains to be solved. Its application in the human environment remains to be further studied. In this paper, an innovative synthesis method of hydrogels with rapid self-healing ability and mechanical toughness in recent years is introduced. And its wide application in medicine. It is believed that self-healing hydrogels have long-term development prospects and considerable possibilities in the future.关键词：Self-healing hydrogel;Polymer materials;Application;Synthesis;Development
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发布时间：2022-08-30 - 摘要：As a new hemostatic material, chitosan has been widely studied in recent years based on the characteristics of antibiosis, hemostasis, non-toxic, thromboplastin, biodegradation and biocompatibility. According to the defect of mechanical properties, hydrophobicity and slow hemostasis rate of chitosan, this paper review the research progress of chitosan with different cross-linking agents for increasing the mechanical properties, such as Jingniping, aldehydes and tannic acids. Furthermore, we also report the research progress of modification of chitosan for enhancing or decreasing solubility in water, such as carboxymethyl chitosan, chitosan quaternary ammonium salt and alkylated chitosan. Finally, we review chitosan composites by adding organic and inorganic materials for improving the hemostatic potential, including polyvinyl alcohol, gelatin and collagen.关键词：Chitosan;Hemostatic sponge;Cross-linking agents;Hemostasis
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发布时间：2022-08-30 - 摘要：In this paper, in order to study the polymerization kinetics involving POSS, the polymerization reaction of MMA and Methacrylolsobutyl POSS (MA7iBu-POSS) was carried out. The conversion curves and the influence curves of the monomer amount on the reaction rate were obtained by weighing method. The results showed that the reaction rate of polymerization reaction increased with the increase of temperature and initiator concentration, and decreased with MMA mass increases. The influence of MA7iBu-POSS on the reaction rate firstly increased and then decreased, and there was an inflection point A. In addition, the activation energy of the polymerization reaction Ea=87.297kJ/mol. The reaction order I(Initiator)=0.617, and n (MA7iBu-POSS)=0.217 when CN was bigger than 0.1239mol/L and n (MA7iBu-POSS)= -0.202 when the concentration of CN was bigger than 0.1239mol/L. Meanwhile, the reactivity ratio r1(MMA)=1.212 and r2 (MA7iBu-POSS)=0.567. Thus, the self-polymerization rate of MMA was bigger than its copolymerization, and the copolymerization rate of MA7iBu-POSS was bigger than its self-polymerization. The distribution of the two polymerized monomers in the polymer was random.关键词：Bulk polymerization;MA7iBu-POSS;MMA;Reactivity ratio;Conversion
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发布时间：2022-08-30 - 摘要：Thermoresponsive phase transition behaviors of poly(N-vinylcaprolactam) (PNVCL) in water-solvent mixtures were investigated. Several aprotic solvents including dimethyl sulfoxide (DMSO), N , N-dimethylformamide (DMF), tetrahydrofuran (THF), 1, 4-dioxane and protic solvents (low molecular weight alcohols) were selected and phase separation temperatures were determined by turbidity measurements using UV-Vis spectroscopy. The results showed that the low critical solution temperatures (LCSTs) of PNVCL increased monotonically with increasing concentration of added DMF, THF, 1, 4-dioxane and CH3OH to the aqueous solution of PNVCL. The addition of DMF and 1, 4-dioxane had the greatest effect on the LCSTs of PNVCL, followed by THF, while methanol has the least effect on its LCST. The addition of small amounts of ethanol, 1-propanol, and 2-propanol to an aqueous PNVCL solution initially decreases the transition temperature, and a further addition increases it. Unlike these alcohols, the LCST of PNVCL gradually increases up to xDMSO=0.1 and then decreases with increasing concentration of added DMSO.关键词：Poly(N-vinylcaprolactam);Low critical solution temperature;Aprotic solvent;Protic solvent
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发布时间：2022-08-30 - 摘要：The adsorption properties of
from water on D301 and MIEX anion exchange resins were investigated. The results showed that the effects of pH on the adsorption of on the two resins were similar. The two resins exhibited the largest adsorption capacities of at pH 4~9. The adsorption capacities of were significantly weakened by the coexistence anions of Cl- , and . The influence of the coexistence anions followed the order . It took only 4 min for MIEX to reach adsorption equilibrium of , and 180 min for D301 to reach adsorption equilibrium of . MIEX exhibited a larger pseudo-second-order rate constant k2 and a larger intraparticle diffusion rate constant kid than that of D301. The adsorption isotherms of on D301 and MIEX were in accordance with Freundlich equation. Adsorption isotherms and adsorption thermodynamics indicated that the adsorption capacities of on MIEX were higher than those of D301. The adsorption mechanism of on D301 and MIEX was anion exchange. 关键词：D301 resin;MIEX resin;Bromate;Adsorption- 12
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发布时间：2022-08-30 - 摘要：Using nickel (Ⅱ) catalyst 1,3-bis(diphenyl phosphine)propane nickel dichloride (Ⅱ), poly(p-benzoquinone diamine-naphthalene) and poly(p-benzoquinone diamine) were prepared. Imine-anthracene) two new copolymers and their performance comparison studies. It was characterized by FT-IR, UV-Vis, CV, XRD and TG methods. The results show that: the two copolymers synthesized in the trifluoroacetic acid (TFA) solution, the absorption wavelengths of the ultraviolet-visible absorption spectrum are 524nm, 293nm and 502nm, respectively. There are absorption peaks at 295nm. The red shift of polymer P1 is 22nm compared with P2. P1 has a higher degree of conjugation; cyclic voltammetry shows that the peak area of P1 is larger than that of P2, and the larger the peak area, the greater the specific capacitance of the copolymer; iodine doping will increase the telephone activity of the copolymer. This article has high application potential and reference value for the electrochemical research of copolymers.关键词：p-Benzoquinone diamine;Ni(Ⅱ) catalyst;Naphthalene;Anthracene
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发布时间：2022-08-30 - 摘要：Polymerization reaction engineering is study that the science of theory and practices of the preparation of polymer, and the polymerization reaction engineering analysis chapter is the core content of the course. Meanwhile, radical homopolymerization is an important part of this chapter.This paper analyzes and deduces some difficult problems in the teaching of radical homopolymerization reaction.In the knowledge of radical homopolymerization, the problems encountered in the initiator initiation process are mainly solved and discussed in detail. In addition, the problem of the total concentration of radical in chain growth reaction and the coefficient in the chain termination reaction rate equation are also analyzed and discussed.关键词：Radical homopolymerization;Elementary reaction;The difficulty;Coefficient;Choose analysis
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发布时间：2022-08-30 - 摘要：In the new stage of the development of "Internet+education", relying on the first-class professional construction project, we explored and practiced the mode of "Internet+experimental teaching" for this profession. The modern information technology patterns such as virtual simulation experiment, large-scale instrument virtual operation software and micro video are introduced into the experiment course teaching, so as to promote the deep integration of modern information technology means and experiment teaching. This kind of online and offline interactive teaching based on network technology enhances students' interest in learning and thinking, improves the breadth and depth of experimental teaching information, and promotes the improvement of experimental teaching level.关键词：Internet+;Polymer specialty;Virtual simulation experiment
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发布时间：2022-08-30 - 摘要：In order to improve learning, application and innovation abilities of students, the course of materials physics has been reformed, such as teaching contents and design, teaching methods and assessment methods. Constructing scientific and rational teaching contents, creating and practicing the teaching design based on design idea of functional materials, flipping the classroom, reforming assignments and innovating evaluation methods, thus the teaching mode of materials physics suitable for training creative applying talents is established, the learning, application and innovation abilities as well as the comprehensive quality of students are enhanced and the "knowledge-ability-quality" education pattern of talents is completed.关键词：Innovation ability;Application ability;Materials physics;Teaching design;Teaching mode
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发布时间：2022-08-30 - 摘要：The remarkable characteristic of application-oriented personnel training lies in "putting learning into practice, taking use as the basis". Based on the perspective of application-oriented personnel training, the reconstruction of the new teaching system of instrument analysis course can not only promote students to think and study in learning, but also help to cultivate students' ability to analyze and solve problems. Therefore, it is of great significance to construct a new teaching system of instrumental analysis course and combine it with quality education.关键词：Instrument analysis;New system of course teaching;Training of applied talents
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发布时间：2022-08-30 - 摘要：The "image teaching" is a completely different teaching mode from traditional classroom teaching which is a development direction of teaching reform in the Internet information age. Firstly, the basic concept of the "image teaching" mode is discussed. The mode is based on "Internet+" by means of rich media, and it is not limited by time and region which can provide choices for different educatees. Then the classification of "image teaching" mode is elaborated and the thinking characteristics is analyzed. At the same time, the material preparation and teaching expression on "image teaching" are discussed. In order to adapt to "image teaching", the experience environment similar to traditional classroom teaching and the shooting environment of online open course video of "image teaching" are constructed, and the specific application is carried out.关键词：Image teaching;Teaching mode;Virtual teaching environment
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发布时间：2022-08-30 - 摘要：Based on computational thinking and tooling and concrete problem-solving method, the Gaussian software was used in the teaching of polymer chemistry to present directly, accurately and animatedly the process of back biting in free radical polymerization of ethylene, the propagation in free radical polymerization of vinyl chloride and of ethylene, and the structure of the chain radical in free radical polymerization of ethylene. And this make them visible and vivid, and can be understood easier and more accurately by the students. With UHF/6-31G(d), it is found that all the H atoms in the chain radical in free radical polymerization of ethylene have partial positive charge, while all the C atoms have partial negative charge, and the activation energy of the process of back biting via six-membered ring transition state forming C4 branch is 115.6kJ/mol. It is also found that during the transfer of H atom in the above back biting process, the positive charge of the transferring H atom is decreased, the negative charge of the C atom that the H atom is transferring to is increased, and the negative charge of the C atom that the H atom is transferring from is decreased, and the energy of the 2° radical formed being 9.3kJ/mol less. The calculations also show that back biting via seven-membered ring and fivemembered ring transition state forming C5 and C3 branch, respectively, having activation energy of 99.7kJ/mol and 150.6kJ/mol.关键词：Gaussian software;Polymer Chemistry;Teaching;Ethylene;Free radical polymerization;Back biting;Vinyl chloride;Propagation;Free radical;Structure
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发布时间：2022-08-30
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