最新刊期
卷 31 ， 期 5 ， 2018
- 摘要：In accident and surgery, uncontrollable bleeding is the main cause of death. The absorbable hemostatic materials of superior performance can speed up coagulation process so as to save lives of many patients and improve the survival rates of patients efficiently. Due to their biodegradable performance, absorbable hemostatic materials need not to be removed again form the wound surface after the completion of hemostatic function. Therefore, absorbable hemostatic produces are safe and efficient. In recent decades, based on different hemostatic mechanisms, many hemostatic materials and products have been developed and reported, thus playing an important role in different hemostasis application. In the present investigation, we reviewed the researches and applications of biodegradable hemostatic materials and products in domestic and international medical market. Additionally, the research direction of absorbable hemostatic materials is prospected therein.关键词：Absorbable;Hemostatic materials;Researches and applications
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发布时间：2022-09-05 - 摘要：Polyaniline (PANI) and transition metal oxide (TMO) have good physical and chemical properties, however, their applications in many areas are still subject to their own limitations. While the nanocomposites formed by PANI and TMO can bring synergistic and complementary effects, which can effectively overcome their own defects and improve the electrochemical properties of the composites. In this paper, the preparation of PANI-TMO nanocomposites with tubular, rod, spherical, fibrous and flower morphologies is reviewed, using hard template and soft template synthesis methods. A chemical oxidative method to polymerize aniline on the surface of TMO is reviewed emphatically. The applications of nanocomposites with a diversity of morphologies in the electrochemical fields, such as supercapacitor, lithium ion battery and sensor, are also summarized.关键词：Polyaniline;Transition metal oxide;Composite material;Electrochemical properties
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发布时间：2022-09-05 - 摘要：Magnetorheological elastomer (MRE) is developed from magnetorheological fluid (MRF). MRE materials avoid disadvantages such as easy settlement of MRF, poor stability, low wear resistance and so on.It had the advantages of fast response speed, good reversibility, simple structure design and low preparation cost. Therefore, MRE materials are widely used in vibration isolation, vibration control and stress displacement sensor.By summarizing the preparation methods and related properties of MRE materials, it can accelerate its development.This paper summarized the preparation methods, properties and application of MRE materials in recent years, and looked forward to the future development direction.关键词：Magnetorheological elastomer;Filling particles;External magnetic field;Application
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发布时间：2022-09-05 - 摘要：The magnetic rubber is a kind of functional polymer composites with such advantages as magnetism and elasticity, easy processing, diverse shape, good flexibility and so on. So it has been widely used in many fields. In recent years, magnetic rubbers have attracted great attention in the international academic and industrial fields due to their particular structure, good properties and bright future applications. More and more researchers devote themselves into the research of magnetic rubbers. This paper mainly introduces the basic composition, common preparation technology and research status of magnetic rubbers, and summarizes the present application state of magnetic rubbers in the fields of industry and people’s daily work and life. Finally, current research trends and possible future perspectives of magnetic rubbers are briefly described.关键词：Magnetic rubber;Rubber;Polymer;Magnetism
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发布时间：2022-09-05 - 摘要：In this study, we first used L-Lactide and Glycolide to synthesize the crosslinkable PLG9010 which can undergo crosslinking reaction. The crosslinking reaction was induced by photoinitiator and then the effect of irradiation time on the polymer properties was discussed. We found that the gel content and mechanical properties of crosslinked PLG9010 showed an upward trend with the increase of irradiation time. Under the condition of 1.0%(wt) photoinitiator and 20 minutes irradiation time, the gel content of crosslinked PLG9010 could reach 97.5%. Secondly, we used the femtosecond laser cutting technology to prepare biodegradable scaffolds with the crosslinked PLG9010 tubes and then the crush resistance, degradation behavior and animal experiments are studied. Stored at 25℃ for 6 months, the crush resistance of the stents still stays at 88.65kPa. In the static degradation system at 37℃, the gel content of crosslinked PLG9010 still maintains 88.9%.Rabbits were implanted with the PLG9010 scaffolds for the animal experiments. After implanted, expansion was obviously observed and there was no damage at the blood vessels. At 2 hours after operation, there was no shift with the stent at the site of implantation and the vessel kept dilation under the microscopic anatomical observation.关键词：Biodegradable scaffold;L-Lactide;Glycolide;Animal experiment
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发布时间：2022-09-05 - 摘要：A kind of fatty chain siloxane dispersion was successfully synthesized by segmentally controlling temperature and feedingvia two-stage temperature control and feeding, and the associated coating was fabricated on glasses. The water contact angle and the rolling angle of the coatings could reach to 158° and 2°, respectively. Besides, the effects of the concentration of catalyst, water and siloxanes as well as and the reaction time on the morphology and wettability of the coating were investigated. With low water content, the superhydrophobicity of the coating is improved with the increase of catalyst content, water content and the content of catalyst, water and fatty chain siloxane. However, the excessively addition of excess catalyst, or water or long-chain siloxane could lead to cracking of the coating. Thereby the optimal reaction conditions for the synthesis of the dispersion could be determined. More importantly, the introduction of the fatty chain of siloxane could provide the coating with both hierarchical structure and low surface energy groups.关键词：Sol-gel;Fatty chain siloxane;Dispersions;Superhydrophobic coating;Morphology
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发布时间：2022-09-05 - 摘要：Crosslinking microspheres were firstly synthesized through emulsifier-free emulsion polymerization with styrene (St), divinylbenzene (DVB) and dimethyl diallyl ammonium chloride (DADMAC) as the monomers. Futhermore, microporous structure in the polymer microspheres were knitted via Friedel-Craft acylation’s reaction with 1,2-dichloroethane as swelling agent, formaldehyde dimethyl acetal (FDA) as external crosslinker, and ferric trichloride (FeCl3) as catalyst. Finally, graphene oxide/microporous polymercomposite microspheres (GO/HCMPs) were prepared via cladding GO to HCMPs by means of electrostatic interactions. Scanning electron microscope (SEM) images, Zeta-potential and particle size analysis results show the surface of the microsphere is positive and the particle size of microspheres is monodisperse. Nitrogen sorption isotherm and pore size distribution indicate that HCMPs combine massive micropores and its specific surface area is as high as 902m2/g. Transmission electron microscope (TEM) images, Raman spectra and X-ray photoelectron spectroscopy (XPS) show that GO sheets are successfully coated on the surface of HCMPs.关键词：Graphene oxide;Hyper-crosslinked microporous polymer;Composite microsphere
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发布时间：2022-09-05 - 摘要：In order to improve the spheronization and mechanical properties of drug-loaded microspheres, rutin-loaded microspheres were prepared, where CHI with oppositely charged ALG-Na was deposited on different layers through complexation by layer-by-layer self-assembly method. In this method, CaCO3 microspheres as adsorbent were made by stirring coprecipitation method and rutin-loaded ALG-Ca template gel was prepared by ion cross-linking method. This paper utilized FT-IR、SEM、swelling test and drug release experiment in vitro to characterize the properties of drug-loaded microspheres. The results showed that CaCO3 microspheres as adsorbent could enhance the spheronization and mechanical properties of the drug-loaded ALG-Ca/(CHI/ALG)3 microspheres. The multilayer structure were formed on edge of vertical section of microsphere. The membrane thickness was approximately 20.22μm. Meanwhile, by investigating the drug release experiments of ALG-Ca/(CHI/ALG)n microspheres, it was found that when pH of the normal saline was 1.2, pH of PBS was 6.8 and the temperature of the solution was 37℃, the more layers the microspheres have, the lower the rutin release rate is.关键词：CaCO3 microsphere;Layer-by-layer self-assembly;Alginate;Chitosan hydrochloride;Rutin
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发布时间：2022-09-05 - 摘要：By Prepolymer Process, the polyfunctional thiol terminated polyurethane oligomer was prepared with polyfunctional polyether polyols, isophorone diisocyanate(IPDI),and by adding an end-capping reagent-mercaptoethanol. The crosslinked polyurethane containing disulfide bonds was then polymerized by oxidative coupling of the thiol moieties using sodium iodide/hydrogen peroxide.The resultant polymers were characterized by FT-IR. The effect of self-healing condition, self-healing efficiency,the function of disulfide bond and hydrogen bond in self-healing process were analyzed by means of tensile test and contrast test,etc. The results showed that the crosslinked polyurethane containing aliphatic disulfide bonds can achieve efficient self-healing at room temperature, and does not require additional catalyst and external stimulus.After being cut in half with a razor blade and simple contact,the samples were exposed to natural light for 48 hours, the tensile strength can be restored to 95% of the original, and the elongation at break can be restored to 100% of original. which hydrogen bonds among urethane moieties contributed up to about 30% of the healing efficiency.关键词：Crosslinked polyurethanes;Thiol;Disulfide;Self-healing;Dynamic reversible covalent bond
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发布时间：2022-09-05 - 摘要：In this paper, polyvinyl alcohol as dispersing agent, Benzoyl peroxide as initiator of polymerization, Divinyl benzene as cross-linking agent, Styrene and 2-Methylpropenoic acid as monomer, pH sensitive P(St-DVB-MAA) hydrogel were prepared by suspension polymerization on 80℃.The structures, components and properties of the prepared composite microgels were characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA). The effects of time, pH and salt solution on the swelling behavior of P(St-DVB-MAA) were investigated, and the relationship between the swelling rate and ion adsorption capacity of hydrogels was also discussed.The experiment of ion exchange was conducted by resin to deal with Zinc ions in the solution. The results show that P (St-DVB-MAA) has a good pH responsiveness, and its swelling rate is closely related to ion exchange adsorption capacity.关键词：Hydrogels;St-DVB-MAA copolymer;Ion exchange adsorption;pH-sensitivity
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发布时间：2022-09-05 - 摘要：Silicone rubber materials have been widely applied in sealing, damping, cementing, and coating of spacecraft for their superior high-low temperature and radiation resistances, as well as excellent electrical performance. The environmental features of Low Earth Orbit (LEO) and the properties of silicone rubber materials in the resistances of vacuum, high-low temperature, atomic oxygen, and radiation were introduced, and the development trends of space-grade silicone rubbers were proposed.关键词：Low earth orbit;Silicone rubbers;Environmental adaptability;Aging
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发布时间：2022-09-05 - 摘要：Petroleum resin has excellent compatibility, adhesiveness and thermal stability, and because of its variety, it can meet the special requirements of different industries, especially rubber industry for polymer materials, so it has been widely applied in rubber industry. In this paper, the classification and properties of petroleum resins are reviewed. The emphasis is laid on the production of hydrogenated petroleum resins with excellent properties through the introduction of suitable active groups, modification and hydrogenation modification, especially the modification and application of C5 and C9 petroleum resin were introduced in detail. The research and application of different types of petroleum resins in the domestic rubber-based tire industry, and outlined the current situation and development prospects of petroleum resin. The production status and future development prospect of petroleum resin are also prospected.关键词：Petroleum resin;Rubber;Modified;Application
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发布时间：2022-09-05 - 摘要：The carriers in metals are electrons or holes, however, not the case in polymer with a chain structure. The soliton from the "solitary wave" and polaron forming from soliton and anti-soliton are another types of carriers for conductive polymers. The energy required for movement of polaron and soliton is smaller than that for electron movement in conductive polymers, therefore the carriers should be polaron and soliton instead of electron.关键词：Polymer;conductivity;Soliton;Polaron
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发布时间：2022-09-05 - 摘要：The national strategic emerging industries involve a large number of high polymer material products and technology, which belong to the teaching subjects of polymer materials and engineering specialty. Meanwhile, there is a great demand for the inter-disciplinary and application-oriented talents in the society. This paper summarizes the practicing experience of strengthening the application-oriented specialty of polymer materials and engineering. Teaching contents closely associated with the industrial development are enhanced. A group of large and medium-sized enterprises with professional counterparts participate in guiding the students’ innovative practice activities. School and enterprise jointly arrange a batch of graduation thesis topics with innovative and industrial needs and evaluate thesis quality. The school-enterprise synergy education oriented by the ability and skill of the students can enhance the innovative ability and quality of application-type talents, and provide high-quality human resources matching the needs of polymer industry.关键词：Application-oriented talents;Outcome based education;Polymer materials and engineering;National strategic emerging industries
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发布时间：2022-09-05 - 摘要：The accreditation standard of engineering education emphasizes the student-centered concept, output-oriented education and continuous improvement of teaching quality. "Polymer chemistry experiment" is one of the professional basic course for the students majoring in polymer science and engineering. In addition, it is the important practical link for cultivating inter-disciplinary innovative talents. Based on the existing problems in teaching system of polymer chemistry experiment, the way of teaching reform is discussed in this paper. Based on the student-centered concept, teaching team should establish a set of scientific interactive teaching model through refining teaching procedures, adopting flexible teaching methods and applying rational teaching feedback mechanism. So that, students could maintain exploration and innovation spirit to challenge the traditional knowledge system and eventually become the internationally recognized polymer materials and engineering professionals.关键词：Engineering education accreditation;Polymer chemistry experiment;Feedback mechanism of teaching;Interactive teaching model
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发布时间：2022-09-05 - 摘要：In this paper, the relationships between active chain concentration ([P·]) and conversion (x), conversion and polymerization time (t) with or without the quasi-stable state hypothesis were discussed. Under the quasi-stable state, x~t curve, not [P·]~x curve, is influenced by the operation mode. With the polymerization mechanism of initiator trigger and coupling or disproportionation termination, higher conversion could be gained in batch reactor than that in continuous stirred tank reactor under the same polymerization time. Without the quasi-stable state hypothesis, both [P·]~x curve and x~t curve are influenced by the operation mode. With the polymerization mechanism of initiator trigger and no termination, higher conversion could be gained in continuous stirred tank reactor than that in batch reactor under the same polymerization time. We hope that the results could contribute to the teaching of lectures and studying of undergraduates.关键词：Polymer reaction engineering;Chain polymerization;Engineering analysis
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发布时间：2022-09-05
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