最新刊期
卷 36 ， 期 7 ， 2023
- 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 2022, 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;National Natural Science Foundation of China;Science foundation reform
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发布时间：2023-05-30 - 摘要：UV curable inkjet technology combines the characteristics such as noncontact, facile operation, low cost, no residue of solvents after UV curing, and environmentally friendly of inkjet technology with UV curable system. It has been widely used in braille printing, fabrication of ceramics and electronic devices, manufacture of the textiles, and the modification and protection of the wood surface. The key material in the technology is the UV curable inkjet ink formulated by UV curable monomer, prepolymer, photoinitiator, additives, and assistant. According to the different demands of applications, some functional materials such as metal, metal oxide, carbon nanomaterials, and quantum dot have been added into the ink. UV curable inkjet technology has been used in the fabrication of solder resist layer. The technological difficulty is the adjustment of the adhesive force. The coating should stay on the surface during the etching process, and the layer should be easily moved thoroughly after etching. It is of great significance for the further extend and optimization of the UV curable inkjet technology to learn about key factors and the corresponding adjusting strategy for its application in additive manufacture.关键词：UV curable;Inkjet technology;Braille printing;Electronic device;Manufacture of the textile
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发布时间：2023-05-30 - 摘要：Facing complex internal environment in human body, traditional medical adhesives have bad performance in binding tissues. Mussel-inspired adhesives have excellent underwater adhesion capability, which has arisen much attention on the application of such type of adhesives in the field of biomedical materials. Because dopamine has a similar structure and properties to the catechol in mussel protein, adhesives based on dopamine have been investigated widely. Firstly, the highly active phenolic hydroxyl groups in dopamine-based adhesives can adhere stably to the surface of tissues through covalent or non-covalent interactions. Secondly, the highly active phenolic hydroxyl group can also give adhesives superior cell affinity and cell adhesion. Dopamine-based adhesives can maintain the adhesion property underwater and have the characteristics of biocompatibility and cell adhesion. It can be seen that the addition of dopamine provides a larger room for developing tissue adhesives. This paper reviews the latest research progress of dopamine-based adhesives in the field of biomedical materials. According to the different ways of adding dopamine, the influencing factors of their adhesion strength and structure design are analyzed from two directions: functional hyperbranched polymer and linear polymerization of small molecules. Finally, existing problems and future development of dopamine-based adhesives are discussed.关键词：Mussel;Dopamine;Bio-adhesive;Structure design;Adhesion properties
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发布时间：2023-05-30 - 摘要：Microwave absorbing materials are widely used in stealth technology, electromagnetic compatibility, security protection, microwave anechoic chamber, and have gained much attention. However, the traditional microwave absorbing materials have a single function, which cannot meet the requirements of light weight, thin coating, flexibility, environmental adaptability and so on. Flexible composite microwave absorbing materials generally use a variety of wave absorbing mechanisms, such as conductive loss, dielectric loss and magnetic loss. The wave absorbing efficiency is up to 99.99% or more, and they have the characteristics of folding, bending, twisting and deformation, which provides an important idea for the application of wave absorbing materials in the field of artificial intelligence, robots and wearable devices in the future. This paper focuses on some important research progress of flexible composite microwave absorbing materials, such as carbon based, polymer based, and metamaterial based, and summarizes and prospects the current challenges and future development trends of flexible composite microwave absorbing materials.关键词：Flexibility;Absorbing;Composite;Polymer;Metamaterial
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发布时间：2023-05-30 - 摘要：At present, the detection and monitoring of early aging or slight aging of polymer materials are faced with many difficulties, of which the most urgent need is to develop sensitive and efficient characterization methods. As a very sensitive analytical technology successfully applied in biomedical, environmental science, material science and other fields, fluorescent probe technology has the advantages of low detection limit and strong visibility, which indicates its potential to characterize the early aging of polymers. During the aging process of polymer materials, free radical species, hydroxyl, carboxyl and other groups will often be produced, and the environmental stress, humidity, matrix polarity and other properties will also change, which provides a useful place for the stimulus response behavior of fluorescent probes. In this review, the development history of various fluorescent probes is briefly described, the essential mechanisms of fluorescent probes that label the changes in the aforementioned materials are discussed, the typical applications of fluorescence probes for chemical and microenvironment response are expatiated and the synthesis methods of some probes are exhibited. Finally, the scientific problems and application challenges of fluorescence probe technology are systematically summarized, hoping to be beneficial to the research work of the majority of peers.关键词：Fluorescence probe;Polymer aging;Early-stage monitoring;Stimulus response;Micro-environment
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发布时间：2023-05-30 - 摘要：Using carboxymethyl chitosan (CMCS), calcium carbonate(CaCO3), glucolactone (GDL), glycerol (GLY) as raw materials, hydrogels were prepared by in situ phase transformation, and hemostatic sponges were obtained by freeze-drying process for body non compressive bleeding. The physical and chemical properties, blood safety and hemostatic properties of sponge were studied by scanning electron microscope analysis, water absorption analysis, porosity analysis, hemolysis test and whole blood coagulation time test. When the mass ratio of CaCO3 to CMCS is 15%, the prepared sponge shows the best comprehensive performance. The sponge is porous, and the hemostatic time is 35% shorter than that of medical cotton gauze. It shows no blood toxicity, which is an excellent hemostatic sponge material.关键词：Carboxymethyl chitosan;Calcium carbonate;Glucolactone;Sponge;Hemostasis
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发布时间：2023-05-30 - 摘要：In this work, structural evolution of uniaxially oriented poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) films during stretching and subsequent heating was studied. The mechanism for generating β-form crystals during the second drawing and the transformation of β-form during heating were investigated via in situ synchrotron wide-angle X-ray diffraction (WAXD) and Fourier transform infrared spectroscopy (FTIR), together with the measurement of stress-strain curves. It was found that relative contents, orientation and size of β-form crystals increased with the increase of strain, while the crystallinity,orientation and crystal size of α-form decreased. These results revealed that the packing states of molecular chains in α-form lamellar crystals must be disordered for generating the β form chains. In the following heating process, crystallinity, orientation and crystal size of α-form crystals increased with the increase of temperature, and the β-form crystals gradually disappeared. This was mainly owing to the transformation of the β-form into the α-form with higher orientation. The melting temperature of the β-crystals ranges from 65 ℃ to 135 ℃. This work provides new insight into the structural evolution of PHBV films, which will provide a theoretical basis for the processing and property control of bio-based polyester films.关键词：Poly(3-hydroxybutyrate-co-3-hydroxyvalerate);β-Form;α-Form;Structural evolution
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发布时间：2023-05-30 - 摘要：The influences of molecular weight, residual monomer, end-group type and content, Fries rearrangement structure on capillary rheology of bisphenol A polycarbonates (PC) were systematically investigated in this study. No obvious thermo-oxidative degradation was observed and changes in the end-hydroxyl content, capping type and residual monomer did not deteriorate the degradation of PC chains, suggesting that rheological tests carried out near to 270 ℃ are stable and repeatable. A typical shear-thinning effect was found in the viscosityshear rate curves without accompanying a Newtonian characteristic in the zero-shear-rate region. At the low shear-rate region, the viscosity increases with decreasing the shearing rate to different extents for different PCs. Further studies revealed that the non-Newtonian flow index n in the low shear-rate region remains constant for PC melts with different molecular weights and different testing temperatures. It decreases linearly with the increase of the content of Fries rearrangement structure involved in the PC chains. As PCs fabricated by the melt transesterification have to experience high temperature and high vacuum environment during the long polymerization process, they involve many Fries rearrangement-derived heterogeneous structure. This should be the reason why the n value is significantly lower than that of the phosgene PC, thus leading to higher melt strength and flow activation energy.关键词：Polycarbonate;Heterogeneous structures;Fries rearrangement;Rheology
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发布时间：2023-05-30 - 摘要：Magnetorheological (MR) gel is a new generation of MR materials, which effectively overcomes the shortcomings of easy settlement of MR fluid. MR gel is formed by the soft magnetic particle suspension in the gel-like matrix and its rheological properties are mainly controlled by two factors: magnetic field and temperature. In this work, a polyurethane-based MR gel containing carbonyl iron powder with a mass fraction of 60% was prepared. The influence of temperature on the rheological properties of MR gel was systematically investigated. The results show that temperature has a significant effect on the viscoelastic properties of MR gel. The hysteresis response of harmonic strain signals with frequencies of 0.1, 5 and 15 Hz and amplitudes of 10% and 50% at five temperature levels was measured, the viscoelastic properties of MR gel were analyzed, and the viscoelastic plasticity model was used to predict the nonlinear hysteresis characteristics of MR gel. The analysis results show that the viscoelastic plasticity model can accurately predict the hysteresis characteristics of MR gel at different temperatures.关键词：Magnetorheological gel;Temperature;Viscoelastic behaviors;Viscoelastic-plastic model
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发布时间：2023-05-30 - 摘要：In 2021, polymer materials and engineering of Anhui Jianzhu University was listed as the national firstclass major construction point, which puts forward higher requirements for the talent training ability of this major. Polymer chemistry experiment is the core course of polymer major and an important practical link of it. As the only experimental skills competition in the field of polymer, the National College Students' Polymer Materials Experiment and Practice Competition cultivates, exercises and improves students' various abilities. However, as only a few students can participate in the national competition, it is difficult to benefit more students. Therefore, it is necessary to find a suitable way to apply the results of the competition to conventional experimental teaching. The research group formed the polymer chemistry experiment teaching mode of "competition and teaching integration" from three aspects: introducing reasonable competition, jointly creating experimental competition with enterprises, constructing the curriculum system integrating competition and conventional experimental practice teaching, refining experimental process assessment and reforming experimental operation mode. This model can improve the experimental teaching effect of polymer chemistry and meet the requirements of the construction of first-class major.关键词：National first-class major;Polymer chemistry experiment teaching;Skill competition;Integration of competition and education
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发布时间：2023-05-30 - 摘要：The restrictive relationship between "structure, properties and molecular motion" is the core theory of Polymer Physics, among which "molecular motion" is extreme abstract and brings about great difficulties for students to learn. In response to this problem, a comprehensive experiment about "structure and properties of shape memory poly(lactic acid)/poly(propylene carbonate) blend materials" was designed by integrating the scientific research results of teachers’. By this experiment, students will systematically and specifically understand the relationships of "phase structure and molecular motion" , "molecular motion and mechanical properties" , "molecular motion and shape memory function" . Meanwhile, they will master the experimental technology of thermal analysis, scanning electron microscopy, mechanical properties and shape memory function, and experience the typical application of basic polymer theory in the creation of new materials.关键词：Comprehensive experiment;Polymer Physics;Experimental teaching
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发布时间：2023-05-30 - 摘要：Comprehensive experiment of polymer materials includes four types of experiments: molecular polymerization, performance characterization, product processing, and sample testing, the product processing experiment is a key link between the preceding and the following experimental teaching, which helps to improve students’ understanding of the whole process of polymer materials from polymerization to sample application, enhance students’ understanding of the relationship between theoretical knowledge and practical operation, and cultivate students’ ability to solve complex engineering problems. In the course of comprehensive experimental teaching of polymer materials, the National Teaching and Experiment Demonstration Center of Materials Science and Engineering of a university, introduced self-developed micro-processing equipment into the experimental teaching of product processing, built processing equipment including features of extreme processing technology research, comparative formula design and independent cooperative operation, then concatenated characteristic experimental teaching model of theory test process knowledge.关键词：Comprehensive experiment;Micro-processing equipment;Processing technology;Formula design;Rapid sample preparation
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发布时间：2023-05-30
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