最新刊期
卷 37 ， 期 11 ， 2024
- 摘要：Functional polymer materials containing specific functional groups, structures or functional fillers have broad application prospects in the fields of electronic information, energy and biology. During their manufacturing and usage, damage and variations in chemical compositions and molecular structures would inevitably occur, leading to attenuation and even loss of valuable functionalities. Self-healing functional polymers can achieve the non-structural recovery of functional properties via chemical or physical interactions under external stimuli, which significantly improve service life and durability of the materials. The present article reviews the research progress of self-healing functional polymers triggered by external fields such as mechanical force, electric field, light, microwave, magnetic field, direct heating, humidity/water and chemical reagents. Meantime, the basic principles, implementation processes, and characteristics of various excitation methods are carefully analyzed. Based on the above analyses, the challenges and development trend of this emerging field are further discussed, in hope of promoting practical application of self-healing functional polymer materials.关键词：Self-healing;External conditions;Functional restoration;Functional polymers;Polymer composite materials
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发布时间：2024-11-20 - 摘要：Photoresists prepared with molecular glass as the film-forming resin are a hot spot of investigation in the field of EUV photoresists. The paper introduced the main structure of molecular glass photoresist, collecting journal and patent literature for molecular glasses, which are classified into three categories according to molecular topology: dendritic, cyclic and other structures, listing typical research achievements according to the country and publication time, analyzing the performance of molecular glasses of different structures, summarizing the current state of application of molecular glass photoresists and looking towards its future developments.关键词：Molecular glass;Photoresist;Patent
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发布时间：2024-11-20 - 摘要：Fiber-reinforced thermoplastic resin matrix composites have advantages such as light weight, high strength, corrosion resistance, fatigue resistance, short molding cycle, high production efficiency, and recyclability, which are widely used in aerospace, automotive, shipbuilding, energy, chemical and other industries. The connection between fiber-reinforced thermoplastic resin matrix composites and metals has attracted considerable attention because of their superior characteristics and weight reduction. Achieving reliable connections between the two has become a hot research topic. This work summarizes the research on the principles of laser welding, hot pressing, injection molding, ultrasonic welding, friction welding, resistance welding, and other hot-melt joining technologies between thermoplastic resin matrix composites and metals, as well as the influence of metal surface treatment and joining process conditions on the interface bonding performance. The advantages and disadvantages of various fusion connection technologies are analyzed, and the development trends of hot-melt joining technology for thermoplastic resin matrix composites and metals are further discussed.关键词：Fiber reinforced thermoplastic resin matrix composites;Metal;Joining technology;Surface treatment;Joint strength
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发布时间：2024-11-20 - 摘要：Polyolefin is widely used daily because of its advantages of light weight, low price, adjustable performance, and easy processing. However, due to the difficulty of degradation and recycling, polyolefin not only brings convenience to our lives but also causes serious white pollution. Introducing covalent adaptable networks (CANs) into polyolefin is not only beneficial for achieving polyolefin recycling, but also endows polyolefin with high added value, which is an important measure to solve the problem of white pollution. In this review, the design strategy of polyolefin CANs is introduced in detail, including the types of dynamic covalent bonds and the construction mode of the networks (chemical modification, direct polymerization, and post-polymerization modification). The applications of polyolefin CANs in recycling, self-healing, welding, shape memory, and compatibilization are summarized, and future development is prospected.关键词：Polyolefin;Covalent adaptable networks;Recycle;Self-healing
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发布时间：2024-11-20 - 摘要：In recent years, the research focusing on non-isocyanate polyurethanes (NIPUs) has shifted from exploring reliable synthesis routes to the exploration of functional NIPUs, which has become a new research hotspot. This review summarizes four synthesis methods of NIPUs and introduces the characteristics of each method. Among them, the ring-opening approach of cyclic carbonates has been widely adopted in the synthesis of bio-based NIPUs and functional NIPUs due to its high efficiency and convenience. Subsequently, the review focuses on the progress of NIPU research in functional aspects such as self-healing, reprocessability, shape memory, and water-based formulations. These studies not only enhance the advantages of NIPUs in sustainable development and environmental safety but also increase the feasibility of NIPU technology implementation.关键词：Non-isocyanate polyurethane;Synthesis;Functionality
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发布时间：2024-11-20 - 摘要：A self-healing polyurethane which can be degradable was prepared by introducing hierarchical hydrogen bonds and acylhydrazone bonds into the polyurethane molecular chains. On one hand, the hydrogen bonds between chains provided self-healing function for polyurethane. On the other hand, the pH-responsive acylhydrazone bonds endowed materials with recyclable properties. With the increase of the content of acylhydrazone bonds in polymer chains, the mechanical properties of the material were enhanced, and the tensile strength increased from 23.9 MPa to 54.3 MPa. Mechanical performance tests showed that polyurethane materials exhibited good healing performance, with a healing efficiency of 91.6% at 35 ℃. The self-healing mechanism was explored through variable temperature Fourier transform infrared (FTIR) spectroscopy. The polymer materials with self-healing and recyclable properties are significant for the reduction of waste for future low-carbon society.关键词：Self-healing;Polyurethane;Recyclable
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发布时间：2024-11-20 - 摘要：Hevea brasiliensis is widely used in societal production and daily life due to its excellent physical and mechanical properties. Despite its high demand and broad applications, it still faces limitations such as restricted cultivation areas, susceptibility to pests and diseases, and high costs. Taraxacum koksaghyz rubber, being one of the most promising rubber-producing plants, holds significant potential for optimizing cultivation and application through the study of its composition and structure from different growing regions. In this study, solvent extraction and enzymatic hydrolysis were employed to extract Taraxacum koksaghyz rubber, analyzing its impurity content, nitrogen content, ash content, gel content, plasticity initial value, and plasticity retention index. Fourier-transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) spectroscopy were used to characterize the structure of both Hevea brasiliensis rubber and Taraxacum koksaghyz rubber. Results showed that for solvent-extracted rubber, Taraxacum koksaghyz rubber from Xinjiang had higher impurity and ash content but lower nitrogen content, gel content, plasticity initial value, and plasticity retention index, compared to those from Inner Mongolia. For enzymatically hydrolyzed rubber, Taraxacum koksaghyz rubber from Xinjiang had higher ash content but lower impurity content, nitrogen content, gel content, plasticity initial value, and plasticity retention index, compared to those from Inner Mongolia. The molecular weight of Taraxacum koksaghyz rubber from different origins, extracted by the same method, was similar, exceeding one million. The structure of Taraxacum koksaghyz rubber from different methods and origins was identical to that of natural rubber, being cis-1,4-polyisoprene.关键词：Taraxacum koksaghyz rubber;Origin;Extraction method;Physicochemical properties;Structure
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发布时间：2024-11-20 - 摘要：Gelatin-g-poly(N,N-diethylacrylamide) copolymer (GPD), the temperature responsive graft copolymer, was successfully synthesized by free radical copolymerization reaction using gelatin and N,N-diethylacrylamide (DEAM) as raw materials. Fourier transform infrared spectroscopy (FTIR), nanoparticle size analyzer, spectrophotometry, optical microscopy, scanning electron microscopy (SEM), rotational rheometer, and cytotoxicity test were used to characterize and analyze GPD. The results showed that GPD has been found to respond to temperature change quickly and reversibly, with a measured lower critical solution temperature (LCST) of 29.5 ℃ when the amount of DEAM was 0.25 mL. As the temperature rose above LCST, the GPD aqueous solution turned from colorless and transparent to white and opaque. Further investigation revealed that a slight temperature change near the LCST could alter the hydrophilic-hydrophobic interactions between GPD and water molecules in the solution system. The rearrangement of the GPD molecular chains led to the “hydration-dehydration” phenomenon, also known as the phase transition.关键词：Gelatin;N,N-diethylacrylamide;Nanogel;Temperature responsiveness;Phase transition
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发布时间：2024-11-20 -
Research on Metal-ligand Mechanism and Mechanical Properties of Zn2+-UV Precuring Acrylate Elastomer
摘要：In order to improve the strength and deformation of acrylate elastomer simultaneously, the liquid acrylate resin with different viscosities was prepared through the UV precuring process, then benzoyl peroxide (BPO) and N, N-dimethylaniline (DMA) were used as the curing system, which provided N, O atom coordinating with Zn2+, so that the interaction between molecular chains was increased to enhance the mechanical properties of the elastomer. In the curing process, resin turned from light yellow to purple, and became green eventually after curing completely. The causes of the color change and the mechanism of Zn2+ with the molecular chain of polymer were revealed: when N, O atoms provided by BPO and DMA, respectively, with free radicals coordinated with Zn2+, the system became purple; the system turned green when the free radicals faded away completely. According to the coordination mechanism, metal coordination bonds generated between Zn2+ and the molecular chains were located at the end of the chain, which greatly increased the elongation at break of the elastomer, so that the elongation at break of Zn2+-acrylate elastomer increased to 7400% from 630%. Because of characteristics of the metal coordination bonds, we found that appropriate heat treatment can adjust the number of coordination bonds. After 150 ℃ treatment, the tensile strength and the elongation at break of Zn2+-acrylate elastomer increased by 28.6% and 39.6%, respectively, compared to those of the pure acrylate elastomer. In other words, both the tensile strength and elongation at break of Zn2+-acrylate elastomer increased. This study provides a strategy for metal coordination with acrylate polymer, which is expected to play a significant role in the research of high elongation acrylate elastomer. The elastomer prepared can be used as seals, flexible sensor substrates in scenarios requiring the high extension rate materials.关键词：Photoprepolymerization;Acrylate elastomer;Metal-ligand mechanism;Excellent deformability- 2
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发布时间：2024-11-20 - 摘要：One of the key factors in the formation of phenolic aerogel is the sol-gel transition during the phase separation reaction induced by solution polymerization. In order to study the effect of solvent polarity on the sol-gel process and aerogel structure of phenolic resin, the phenolic aerogel with different pore structures was prepared by using ambient drying and supercritical drying. The aerogel structure was characterized by scanning electron microscopy (SEM) and so on. The results showed that the phenolic aerogel prepared with N-pentanol as the reaction solvent was not affected by the drying method, and the phenolic aerogel with stable physicochemical properties and pore structure could be obtained. The carbon aerogel after high temperature pyrolysis was still not affected by the previous drying method. In this work, by comparing the phenolic aerogel prepared by different polar reaction solvents and drying methods, it is clear that phenolic can effectively undergo the sol-gel process in N-pentanol solvent, and obtain a porous structure with tight particle packing and stable skeleton, avoiding the influence of late drying methods on the physicochemical properties and pore structure of phenolic aerogel. These results provide technical support for the large-scale production and practical application of phenolic aerogel.关键词：Phenolic aerogel;Solvent effect;Sol-gel;Ambient drying;Supercritical drying
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发布时间：2024-11-20 - 摘要：In this study, poly(L‑lactic acid) (PLLA), PLLA/polypyrrole (PPy) and PLLA/poly(ethylene oxide) (PEO) fiber films were prepared by electrospinning, and conductive PPy films were prepared on the surfaces of these films by chemical polymerization. Finally, the samples were prepared into piezoresistive flexible pressure sensors to study their sensing properties. It was found that by controlling the composition of the fiber, the deposition morphology and conductivity of PPy could be regulated, and the performance of the sensor could be affected. Among them, PLLA fiber membranes have strong hydrophobicity, and conjunctival phenomena occur around or between the fibers of PPy membrane. The composite effect with the PLLA fiber membrane is poor, and PPy cannot be deposited on the surface of some fibers. The conductivity measured using the four-probe method is only 0.002 S/cm. PLLA/PPy fiber membrane has good hydrophilicity, and can form a smooth, continuous and dense PPy membrane around its fibers. The composite effect of the PPy and PLLA/PPy fiber membranes is much higher than that of the PLLA fiber membrane, with the conductivity of 0.51 S/cm. The PLLA/PEO fiber membrane has the strongest hydrophilicity, and PEO soluble in water can increase the surface roughness of the fiber, which is conducive to the adsorption of pyrrole monomer for polymerization, and the formation of granular and continuous PPy membrane with a conductivity of 0.62 S/cm. The granular microstructure formed on this surface improves the deformation ability, and the sensing performance is the best when prepared as a piezoresistive flexible pressure sensor.关键词：Electrospinning film;Polypyrrole;Morphology;Conductivity;Piezoresistive flexible pressure sensor
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发布时间：2024-11-20 - 摘要：High-performance hydrogels, known for their excellent toughness, conductivity, and sensing capabilities, are considered as ideal candidates for flexible wearable sensors. However, hydrogels often face a trade-off between mechanical performance and electrochemical properties, limiting their extensive application in flexible wearable sensors. To address the incompatibility between the mechanical and electrochemical properties of hydrogels, we introduced NaCl into a poly(vinyl alcohol)/polyacrylamide (PVA/PAM) dual-network hydrogel. Using a one-pot synthesis method, we prepared the PVA/PAM/NaCl (PAN) conductive hydrogel. The inclusion of NaCl introduces physical entanglements into the PAN hydrogel, providing a dense three-dimensional network structure. The PAN hydrogel exhibits outstanding mechanical properties, including a tensile strength of 1.06 MPa, an elongation at break of 1550%, and a compressive strength of 2.79 MPa, while also demonstrating high electrical conductivity (2.25 S·m–1). Additionally, the strain sensitivity of the PAN hydrogel sensor is 1.089, with a high linear correlation (R2 =0.988), enabling precise and reliable detection of human motion. By attaching PAN hydrogel sensors to various parts of the human body, it is possible to accurately identify signals generated by different muscle movements.关键词：Poly(vinyl alcohol);Flexible wearable;Hydrogel;Ionic conductivity
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发布时间：2024-11-20 - 摘要：Conductive rubber materials with better conductive properties were prepared using conductive graphite and carbon black as functional fillers and nitrile butadiene rubber (NBR) as the base. Six different components were designed with conductive graphene as variables, and experiments were conducted to test the plasticity, vulcanization properties, basic properties, mechanical properties, aging properties, high-temperature properties, electrical conductivity, and electromagnetic shielding effectiveness of the composites. The effect of conductive graphene on the properties of conductive carbon black/NBR composites was investigated, and the results showed that adding conductive graphene into a conductive carbon black/NBR composite could improve the conductivity and reduce the curing time of the composite. The addition of conductive graphene has a significant effect on the aging properties of rubber compounds but has little effect on the high-temperature properties. In addition, the addition of conductive graphene can reduce the mechanical properties of the rubber compound, but the effect is small; the reduction rates of the tensile strength and tear strength are 7% and 7.4%, respectively. In the subsequent research, the dispersion of conductive graphene in rubber will be studied to improve its compatibility with rubber materials.关键词：Conductive graphene;Acetylene black;Nitrile butadiene rubber (NBR);Electrical conductivity;Tensile strength
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发布时间：2024-11-20 - 摘要：Fused deposition modeling (FDM) has become one of the most widely used 3D printing technologies, due to its advantages such as low cost, ease of operation, wide applicability, and strong reliability. It has attracted increasing attention and research in various fields including automobile, aerospace, and medical applications. Patent applications of FDM are analyzed, focusing on patent application trends, patent layout areas, patent applicants and technology themes, providing a comprehensive overview of patent layout in this field. The results indicate that China’s FDM patent applications have been rapidly increasing since 2011, making it the country with the highest number of patent applications in this field. However, the number of overseas patent applications is relatively low compared to that of European and American countries. Among the various technical classifications of FDM patents, the number of patents related to modeling equipment has been rapidly increasing since 2015, gradually becoming the most prevalent technology classification. Innovations in FDM equipment are primarily concentrated on components such as nozzles, feeding mechanisms, motion mechanisms and heating elements. After comparing the technical characteristics of major global applicants, it is recommended that China’s innovators in the FDM field increase their R& D investments in data processing and materials. Additionally, it is crucial to strengthen industry-university-research cooperation and patent layouts in overseas markets with the aim of establishing high-value patent portfolios that offer industry-leading advantages.关键词：Additive manufacturing;3D-Printing;Fused deposition modeling;Patent analysis
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发布时间：2024-11-20 - 摘要：‘Research Methods of Polymer Materials’ is a compulsory course in undergraduate education for the major of polymer materials and engineering. This teaching practice is to cultivate talents leading the development of ‘new quality productive forces’. To overcome the limitations in current forms for material characterization using variant instruments associated with fragmented principal knowledge, a systematic teaching method was proposed that integrated the general fundamental composition-processing-structure-property relationships and the preparation, application and recycling of polyurethane materials. Through exploratory teaching practice, these contents from cutting-edge researches are projected onto polymer fundamentals in both knowledge and technology aspects. Philosophy in dialectics, sustainable development and new quality productive forces are integrated through the whole exploratory teaching. Students are always encouraged to participate into flipped discussions and debates, which can motivate their subjective initiative to understand the core knowledge and critical skills engaged in polymer materials. Through this new teaching practice, a comprehensive and systematic knowledge graph for Research Methods of Polymer Materials will be presented, which can facilitate the training of undergraduates to adapt and lead the development needs for new quality productive forces.关键词：New quality productive forces;Research methods of materials;Polyurethane;Systematic teaching
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发布时间：2024-11-20 - 摘要：The new round of industrial transformation and technological revolution has brought unprece-dented development opportunities. Higher education is the leader of the era’s development and also should be the pioneer of the era’s transformation. Focusing on the goal of talent cultivation, cultivating top-notch innovative talents with strong engineering practice ability, strong sense of innovation, and broad international perspective is not only an important goal of talent training in universities in the new era, but also the main route to meet the talent demand of the new economic development. In order to cultivate top-notch innovative talents in the field of polymer materials, combining the characteristics of material-related majors and the multidisciplinary advantages, Sichuan University has deepened the integration of science and education, industry and education, highlighted the engineering characteristics of Sichuan University, innovated the education mode, and carried out comprehensive reforms in terms of training program, curriculum system, teacher team, cultivation process and management mechanism, and constructed a top-notch innovative talent cultivation mode for successive bachelor-master-doctor training program in the field of polymer materials based on the integration of science and education, industry and education. This study has certain reference significance and promotion value for the cultivation of successive bachelor-master-doctor training program in colleges and universities.关键词：Successive bachelor-master-doctor training program;Integration of science and education;Integration of industry and education;Polymer materials;Talent training mode
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发布时间：2024-11-20 - 摘要：Polymer Physics is the core course of composite materials and engineering at Nanjing Xiaozhuang University, covering a wide range of knowledge from microstructure to material characterization techniques. However, traditional teaching methods cannot fully tap students’ desire for deep knowledge, nor can they arouse their learning enthusiasm and innovation potential. In view of this situation, this study integrated and optimized the course content and incorporated the development case of fused deposition modeling (FDM) 3D printing insoles. The course content covered the combination of theoretical and practical teaching, the integration of interdisciplinary knowledge, and the cultivation of innovative abilities. Teaching methods, such as project-based learning, have been adopted to enhance students’ comprehensive ability and innovative thinking. The teaching effect evaluation shows that the integrated and optimized curriculum helps students to deeply understand polymer physics knowledge, improve their ability to solve practical problems, and improve their satisfaction, laying a good foundation for their future academic or professional development.关键词：Polymer physics;Curriculum integration;Teaching optimization;3D printing
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发布时间：2024-11-20
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