最新刊期
卷 35 ， 期 10 ， 2022
- 摘要：The applications, evaluations, and funding of projects at Organic Polymer Materials Discipline (division II of materials science) of the National Natural Science Foundation of China in 2021, as well as the research progresses and achievements of the executing and finished projects are reviewed. The specific measures in implementing the science foundation reform task and the prospect of the future work of the discipline are also elaborated.关键词：Organic polymer materials discipline;the National Natural Science Foundation of China;Science foundation reform
- 39
- |
- 29
- |
- 2
发布时间：2022-09-09 - 摘要：Self-repairing gel, as an intelligent material, can self-repair its structure and mechanical properties after being damaged by the outside world, which has far-reaching significance in the development of the interdisciplinary development of polymer materials and petroleum engineering. This paper systematically introduced the research progress of self-healing gels in recent years, based on multiple hydrogen bonding, electrostatic-hydrogen bonding, metal coordinationhydrogen bonding, π-π stacking-hydrogen bonding, and catechol-like supramolecular interactions. The interaction laws and self-healing characteristics of different types of supramolecules have been analyzed, and the potential applications of selfhealing gel materials in oilfield drilling, fracturing, reservoir control has been discussed. Materials designed based on multiple supramolecular interactions will promote the intelligent development of oilfields.关键词：Self-repairing gel;Supramolecular interaction;Smart materials;Oilfield chemistry
- 22
- |
- 22
- |
- 0
发布时间：2022-09-09 - 摘要：With the advantages of high modification efficiency, simple operation, and no waste and by-product generation, low-temperature plasma has been studied and applied in the surface modification of poly(lactic acid) (PLA) materials. This paper mainly reviews the effects of different plasma sources and different modification conditions on the surface properties of PLA materials; the research progress of low-temperature plasma modification technology applied to PLA packaging and medical field in recent years; and the safety issues of low-temperature plasma modification technology applied to food packaging field are discussed. Low-temperature plasma modification technology can improve the surface hydrophilicity, biocompatibility, cell adhesion, adhesion of PLA materials, and increase the surface roughness of the material without changing the overall properties of the material, which is a promising modification method that can be widely used in packaging and medical fields instead of chemical and physical methods. It is hoped that it can provide a reference for the application of low temperature plasma modified PLA materials in the packaging and medical fields.关键词：Low temperature plasma;PLA;Packaging;Medical field
- 25
- |
- 25
- |
- 0
发布时间：2022-09-09 - 摘要：The medical catheters are essential consumables widely used in various surgical operations and intubation operations. The super-lubricant polymer coatings on the surface of medical catheters can reduce the tissue friction of the catheter in clinical applications and avoid tissue damage and inflammation. This review summarizes the research of different polymer super-lubricant coating systems, coating adhesion optimization and antibacterial modification, and introduces the research progress of polymer super-lubricating coating systems such as polyvinylpyrrolidone, polyacrylamide, polyethylene glycol, natural polysaccharide and derivatives, as well as the method of improving the coating adhesion with silane coupling agent and photochemical reaction, and the latest research on the antibacterial modification of hydrophilic coating by inorganic antibacterial agent, organic antibacterial agent and drug loaded coating.关键词：Medical catheter;Polymer coatings;Super-lubricant hydrophilic coatings;Adhesion;Antibacterial modification
- 29
- |
- 22
- |
- 0
发布时间：2022-09-09 - 摘要：Multi-layer co-extrusion, as a one-time molding processing method, avoids the traditional compounding, coating and other post-processing process, which can effectively reduce the production cost; At the same time, the film prepared by multi-layer co-extrusion method can have excellent properties of various polymers, and has been widely used in food, medicine, daily chemicals and other fields. This paper provides an overview of the structure, performance and application fields of multi-layer co-extrusion films, summarizes the application in various fields and focuses on the development of biodegradable multi-layer co-extrusion films. The development trend of multilayer co-extrusion films is prospected.关键词：Multi-layer co-extrusion;Biodegradation;Mechanical Strength;Barrier properties
- 32
- |
- 23
- |
- 0
发布时间：2022-09-09 - 摘要：This article reviews the influence of the third component in the single-site catalyst system for olefin polymerization. As an unnecessary component for the formation of active centers, the third component has an important influence on the polymer structure and polymerization behavior. This article deals with the influence of the third component of metal alkyls on the structure, composition, molecular weight and polymerization behavior of the polymer, and summarizes the influence of the third component on the polymerization of a single catalyst system, a composite catalyst system, and a single monomer and multiple monomers. The chain transfer mechanism, coordination chain transfer polymerization principle and chain shuttle polymerization technology are presented.关键词：Single-site catalyst;The third component;Chain transfer;Coordination chain transfer polymerization;Chain shuttle polymerization
- 20
- |
- 21
- |
- 0
发布时间：2022-09-09 - 摘要：Ultra high molecular weight polyethylene (UHMWPE) has been widely used as a kind of antifriction and wear-resistant materials because of its excellent mechanical properties and low friction coefficient. However, the low surface hardness and poor abrasive resistance of UHMWPE make it easy to be friction failured, which greatly affects its application in high wear-resistant fields. In this paper, the external and internal factors affecting the abrasion properties of UHMWPE are summarized, the friction and abrasion mechanisms and their research progress are overviewed. The wearresistant modification methods of UHMWPE and their research progress are expounded in details from four aspects of using lubricant, blending modification, cross-linking modification and constructing wear-resistant coating on the surface of UHMWPE products, which provides the experimental and theoretical basis for the preparation of high wear-resistant UHMWPE materials.关键词：Ultra high molecular weight polyethylene;Abrasion mechanism;Wear-resistance modification
- 49
- |
- 38
- |
- 0
发布时间：2022-09-09 - 摘要：Tris(2,3-dichloropropyl) phosphate (TDCPP) and polyphosphoric acid (PPA) are compounded into a new composite flame retardant and used for flame retardant poly(methyl methacrylate) (PMMA). The flame retardancy and combustion behavior of materials were evaluated by limited oxygen index (LOI), UL-94 and cone calorimeter test (CCT). The residue structure of the gas phase products and solidification phases of flame retardant materials during the thermal degradation process were studied by TG-FTIR and FTIR, and the flame retardant mechanism of the compound flame retardant in the PMMA material is speculated. It is found that the LOI of flame retarded PMMA can reach 27.1% and UL- 94 V-0 rating can be achieved at 18 wt% (the mass ratio of TDCPP to PPA is 5∶1) compound flame retardant loading. At the same time, the material has excellent heat resistance and physical properties. The PMMA casting plate material prepared by this method has been industrialized.关键词：PMMA;Phosphate ester;Compound;Flame retardant
- 25
- |
- 23
- |
- 0
发布时间：2022-09-09 - 摘要：In this paper, the pH-responsive hydrogels with self-healing properties were rapidly constructed by introducing dynamic chemical acylhydrazone bonds. Firstly, the cross-linkage(β-CD-(NH2)7) with certain seven reactional points were synthesized by the reaction of iodine, azide and amination of whole 6-OH of β-cyclodextrin. Then, benzaldehyde-terminated polyethylene glycol(PEG-FA) was synthesized by esterification of polyethylene glycol and pcarboxybenzaldehyde. Fourier transform infrared spectroscopy(FT-IR), 1H-NMR, 13C-NMR and matrix-assisted laser desorption ionization time-of-flight mass spectrometry(Maldi-TOF-MS) were used to characterize the products. Secondly, the pH response hydrogels based on reversible dynamic chemical bond were prepared by schiff base reaction of β-CD- (NH2)7 and PEG-FA. The lowest gel concentration, sol-gel transition and self-healing ability of the hydrogel were also studied. Through the response of external pH, the reversible chemical bonds can be broken and recombined, and the dynamic equilibrium relationship between reactants and generators can be established to complete the hydrogel formationbreakage- healing process. Basic cell experiments can also prove the potential application of the synthesized hydrogel.关键词：Dynamic chemical bond;β-Cyclodextrin;Schiff base reaction;Self-healing property
- 18
- |
- 20
- |
- 0
发布时间：2022-09-09 - 摘要：Traditional polymer with network structures possess stable and excellent performance, however, once damaged, they cannot be self-healing and reprocessing. Currently, most of the monomers originated from non-renewable coal and petroleum resources, which aggravates the crisis of non-renewable resources. Vitrimer featured with reversible covalent crosslinking networks can be rearranged its network under external stimulation to promote its reprocessing and self-healing capability. In this work, epoxy vitrimers were prepared by epoxy-thiol "click" reaction between epoxy soybean oil with abundant epoxy group as matrix and BDB (2,2'-(1,4-Phenylene)-bis[4-mercaptan1,3,2-dioxaborolane]) with —SH group as crosslinking agent. The effect of the content of crosslinking agent on the structure and properties of vitrimer polymer was studied. When the epoxy group and thiol was equivalent, the vitrimer polymer displayed the best properties (excellent reprocessing, self-healing, and welding ability).关键词：Vitrimers;Boronic ester bond;Self-healing;Reprocessing;Welding
- 26
- |
- 24
- |
- 0
发布时间：2022-09-09 - 摘要：In this paper, α-linolenic acid (ALA) as the hydrophobic fatty long chain and urea as the hydrophilic group were grafted onto carboxymethyl chitosan through acylation reaction to prepare amphiphilic chitosan derivatives (U-CMCSg- ALA), and its structure was characterized by Fourier infrared spectroscopy and nuclear magnetic resonance hydrogen spectroscopy. Then, the drug-loaded nano-micelles (CTD@ U-CMCS-g-ALA) were prepared by the ultrasonic selfassembly method using U-CMCS-g-ALA as the wall material and clothianidin (CTD) as the core material. The scanning electron microscope (SEM) image of nano-micelles showed that the nano-micelles had a spherical shape with a uniform particle size distribution, with an average particle size of about 465 nm. In vitro release revealed that the CTD@U-CMCSg- ALA nano-micelles exhibited a sustained and pH-responsive drug release property at room temperature. Finally, the antifeedant activity of CTD @ U-CMCS-g-ALA nano-micelles on sugarcane borer was tested by the artificial feed incorporation method. The results showed that the drug-loaded nano-micelles could effectively inhibit the growth and development of the sugarcane borer and the antifeeding rate of CTD@U-CMCS-g-ALA on sugarcane borer wend down by more than 14.3% compared with unembedded clothianidin, which was mainly due to the encapsulation effect of the wall material U-CMCS-g-AlA that could reduce the antifeeding performance against larvae and thus showed better insecticidal activity.关键词：Carboxymethyl chitosan;Amphiphilic;Nano-micelles;Self-assembly;Insecticidal
- 19
- |
- 16
- |
- 1
发布时间：2022-09-09 - 摘要：The purpose of this study is to further verify the mechanism of transglutaminase (TGase) cross-linking soybean protein isolate (SPI). The mechanism of SPI cross-linked with transglutaminase is simulated by Gaussian software, which is usually used in the field of the heterogeneous catalysis and biocatalysts. And the catalytic process is simulated by the chemical method. The results show that the center of transglutaminase activity comnected with 5 amino acids is the optimal structure by calculation. The enzymatic catalysis of the lysine and glutamine dehydrogenation reactions is simulated. The calculating results indicate that there are 8 possible deamination reactions. However, only 2 reactions can be carried out smoothly. Each method has a certain proportion, that is, glutamine amide γ-amide and lysine ε-amino hydrogen. Deamination reaction occurred between amino group and lysine toxic amino hydrogen, and the energy barriers of the reaction process were 49.50 and 44.35 kcal/mol, respectively. SPI can be cross-linked randomly to produce high molecular weight polymers. As a result, the functional characteristics of SPI is changed, and the gel strength of isolated soybean protein is improved.关键词：Gaussian software;Transglutiminase;Cross-linking;Soy protein isolate;Mechanism
- 14
- |
- 12
- |
- 0
发布时间：2022-09-09 - 摘要：Cellulose fabric is susceptible to water contamination and can even breed bacteria in the process of using. In order to reduce the influence of pollutants on the performance of the fabric, it is necessary to modify it for anti-pollution. In this study, the cellulose fabric is treated sequentially in dopamine and copper sulfate solution, copper ions are reduced to copper element by sodium borohydride, and the treated fabric is immersed in the hexadecyltrimethoxysilane(HDTMS) solution to prepare the fabric with anti-pollution properties. The results show that the contact angle of the resultant antipollution fabric is 155°, which meets the requirements of a superhydrophobic surface, and the antibacterial rates against both E.coli and S.aureus have reached 99.9%. After 24 h of ultrasonic treatment, the fabric still maintains stable antipollution performance. The anti-pollution fabric prepared in this article has both water-resistant pollution and biodegradable characteristics, and it is expected to expand its application in the medical and health field.关键词：Cellulose fabric;Dopamine;Anti-pollution performance;Superhydrophobicity
- 31
- |
- 17
- |
- 0
发布时间：2022-09-09 - 摘要：PLLA/CA honeycomb composite porous membranes were prepared via Breath Figure method under certain humidity and temperature conditions with PLLA and CA as film materials. The effects of factors, such as solvent, relative humidity, polymer concentration, the ratio of polymer, and temperature, on the pore patterns and sizes were investigated. The results show that the pore size of PLLA/CA membranes increases from 1.67±1.34 μm to 5.01±1.34 μm with increasing relative humidity from 43% to 91%. The relationship of pore size and the relative humidity is presented first order liner relationship. Moreover, the slope of straight line is 0.068, which indicates that for every 1% in relative humidity, the pore size increases by 0.068 in this system. When the polymer concentration increases from 1 wt% to 6 wt%, the pore size of honeycomb increases first and then decreases. When the temperature is in the range of 10~50 ℃, the ambient temperature has no significant effect on the pore morphology and size. The water contact angle of pure PLLA honeycomb membrane is 128.1°±2.4°. With the increase of CA content, the water contact angle of porous membrane decreases. When PLLA/CA=5∶5, the water contact angle was 50.2°±1.4°, indicating that a certain amount of CA was added into the system, the hydrophilicity of the porous membrane was improved, which was conducive to the adhesion, migration, reproduction and growth of cells on its surface.关键词：Breath figure;Polylactide;Cellulose acetate;Honeycomb;Hydrophilicity
- 20
- |
- 15
- |
- 0
发布时间：2022-09-09 - 摘要：The preparation of layered polymer nanocomposites using layered silicates such as montmorillonite is one of the three preparation methods of polymer nanocomposites. The structure of montmorillonite in polymer has an important impact on the properties of nanocomposites. Therefore, there exists a structure-property relationship between montmorillonite structure and nanocomposites. Only by fully understanding this relationship can we completely grasp the great improvement brought by layered nanomaterials to the properties of polymer materials. The traditional teaching method is abstract and boring, which leads to students' inability to fully master it. In order to achieve better teaching effect, the author compares this structure-property relationship with famous dishes, and draws exquisite corresponding pictures. Finally, through visual teaching, their understanding and mastery of this kind of relationshop is enhanced in fun. Practice proves that the students have a comprehensive grasp of structure-property relationship, leading to a good teaching effect recognized by most students.关键词：Layer polymer nanocomposites;Structure-property relationship;Visualization teaching
- 46
- |
- 34
- |
- 0
发布时间：2022-09-09 - 摘要：Polymer science in pharmaceutics is one of the key courses of applying polymer materials into the process of design and manufacturing of pharmaceutics. For its comprehensive and practical instructional objectives, a overall knowledge structure forming is required. Thus, a teaching method involved a preparation for integrating scattered knowledge points into systematic hierarchy, a program of building up a " holistic view" thinking mode, and PBL mind mapping method were involved in teaching duration. This teaching process focuses on capability for analyzing and practicing of undergraduates majoring in pharmaceutics preparation, and will significantly improve the teaching quality of Polymer Science in Pharmaceutics and achieve the goal of the course.关键词：Polymer science in pharmaceutics;PBL mind mapping;Guided by the problem;Inductive comparison
- 21
- |
- 21
- |
- 0
发布时间：2022-09-09 - 摘要：In order to improve students' enthusiasm and initiative in learning Polymer Chemistry and Physics, the reverse course matrix method was used to design the course. The teaching objectives, teaching methods and evaluation methods highlight the design ideas of student-centered, output-oriented and sustainable improvement. The students' learning direction is more clear by compiling the course matrix, which clearly present the specific teaching objectives, students' learning methods, teachers' teaching methods and assessment indicators to students, Through the online learning platform (Chaoxing), teachers can release teaching matrix and provide teaching resources,while students study by themselves, evaluate and submit homework. According to the statistical data of the platform, teachers can understand students' learning situation and adjust teaching strategies in time. After iteration and improvement, the teaching innovation effect is initially shown, and the students' autonomous learning ability is gradually improved.关键词：Polymer;Curriculum matrix;Reverse design;Teaching mode
- 23
- |
- 20
- |
- 0
发布时间：2022-09-09 - 摘要：Extrusion granulation is one of the most important components of the molding industry, and is exhibited both in the talent training scheme and core competence assessment in polymer materials. Aiming to help students to highly master the knowledge and related skills of the extruder (extrusion granulation), this paper introduces a kind of new teaching mode, which construct an unreal extruder (extrusion granulation) by using virtual reality technology. Importantly, we have owned the software copyright of the "Extruder (Extruding Granulation) Craft Simulation Software V1.0" (NO. 2019SR1039132). As a result, students can learn the whole extrusion granulation craft on computer rather than in person. Additionally, the new teaching mode will further stimulate students' interest in learning professional knowledge and helps to improve the ability to operate in real and analyze-solve problems.关键词：Extruder (Extrusion granulation);Virtual reality technology;Effectiveness analysis;Student evaluation
- 20
- |
- 21
- |
- 0
发布时间：2022-09-09 - 摘要：Polymer Physics is a professional basic course for students majored in polymer materials. It plays an important role in enhancing students' thinking ability, helping students understand professional knowledge and improve their ability for practical applications. In the Internet era, following the OBE teaching concept of "student-oriented and output oriented" , it is necessary to take full advantage of the online teaching to closely combine online and offline teaching to construct the online and offline mixed teaching mode of Polymer Physics based on MOOC. Taking "molecular movement of polymer" section as an example, the online and offline mixed teaching mode composed of three stages of "selfstudy before class-offline Teaching (face-to-face teaching)-review and consolidation after class" are elaborated in detail. Learning effectiveness is evaluated by means of teaching goal achievement and student questionnaire survey, and the results show that the mixed teaching mode could improve students' learning interest and motivation, and the teaching effect is excellent.关键词：Online teaching;Mixed teaching mode;OBE teaching concept;Polymer physics
- 32
- |
- 21
- |
- 0
发布时间：2022-09-09
- Technical support is provided by Beijing Founder electronics co., LTD 京ICP备09064830号-19
京公网安备11010802024621 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
0