最新刊期
卷 30 ， 期 11 ， 2017
- 摘要：Aliphatic polyester is one kind of the biodegradable polymers that has been more and more suffered concerning. Due to the fact that in clinical application all of the medical products will contact with the tissues or blood of the organization in different level, and in the case the surface of the medical products will be firstly contact with the tissues or blood of the organization. Therefore the surface biocompatibility of the medical products has more directly relationship with the safety and effectiveness of the products. In the present paper, the specific property of the aliphatic polyester and the influence factors of specific property on surface biocompatibility of the medical products were analyzed. Then the surface modification methods such as physics, chemistry and plasma processing methods, their merits, shortages and limitations for application of various method were also analyzed and pointed. It is expected that the paper can provide and to supply the modified method to improve surface biocompatibility of the aliphatic polyester made medical products.关键词：The biological material;The aliphatic polyester;The biocompatibility;The surface modification
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发布时间：2022-09-06 - 摘要：For over 30 years interventional cardiovascular stenting has been developed from bare metal stents to drug- eluting stents and even today's emerging bioabsorbable stents, continuing to advance the technological therapy for the coronary heart disease. The idea of bioabsorbable stents is to leave no foreign body behind. In general, the stent functions to keep open a blocked artery and maintain the blood flow only until the vessel heals itself, so it would be ideal for the stent to disappear thereafter. Bioresorbable Polymeric Scaffold (BRPS) has gained a great deal of interest in the biomaterials field nowadays because it is made from a polymeric material which can be designed and modified for its intended use, while serving as a good drug carrier. This article discusses the roles of biomaterial, structure and processing in influencing the functions of a BRPS device, with an emphasis on the two manufacturing methods by laser cutting and 3D printing, as well as the degradation kinetics of BRPS. The challenges and trend of BRPS are also discussed.关键词：Bioresorbable scaffold;Bioresorbable polymer;Structure;Processing;Degradation kinetics
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发布时间：2022-09-06 - 摘要：Chitosan is the only alkaline polysaccharide found in nature, due to its natural sources rich, biocompatibility, biodegradability, non-toxic, antibacterial strong and other good properties. Now,its broad-spectrum antibacterial has been widely recognized, but it’ s further application is limited because of its sparingly solubility in water. Therefore, chitosan derivatives has been one of the hot spots in the research of chitosan, which has been modified by some modification methods to improve its solubility. In this paper, several common hydrophilic chitosan modification methods and application of its derivatives in antibacterical fields were reviewed, which could provide the reference in the further activity study of chitosan.关键词：Chitosan derivatives;Water solubility;Antibacterical activity
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发布时间：2022-09-06 - 摘要：Polyester materials have a wide range of applications in medical fields, in particular, they can be used as a drug releasing materials in the human body. Polyesters used as drug releasing materials need to meet the requirements of having enough modification sites to facilitate bonding drug molecules or other small molecules. For conveniently and efficiently bonding of small molecular to the polyester chains, the current hot reaction-" click reaction" have to be invovled to bond small molecular, which requires to introduce the functional groups into the polyester chain for the " click reaction". Therefore, it is necessary to prepare cyclic ester monomers functionalized with double bonds and triple bonds for further ring-opening polymerization to obtain polyesters with double bonds and triple bonds on the chains. In this review,we introduce the functional cyclic ester monomers which polymers can be modified by " click reaction" in recent years. We divided the cyclic ester monomers into three kinds to introduce the synthetic methods in details. Research progresses of the results in the functional polyesters are highlighted, with focusing on the molecular bonded with the polyester chains and the new properties they have. Furthermore, the applications of the functional polyesters materials are prospected.关键词：Functional cyclic ester monomers;Click reaction;Polyester;Ring-opening polymerization
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发布时间：2022-09-06 - 摘要：This paper introduces the research progress of the synthesis and Flame retardancy properties of 9,10- Dihydro-9-oxa-10-phosphaphenanthrene10-oxide (DOPO) and its derivatives, which were widely studied in recent years. The direction of future research is also discussed.关键词：DOPO;Derivative;Flame retardancy properties
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发布时间：2022-09-06 - 摘要：The problem of rubber filler has always been the hot topic. In view of the pollution problem of carbon black and silica in rubber production, the diatomaceous earth with similar structure to silica has been chosn to fill all kinds of rubbers in this work. Firstly, the diatomaceous earth has been modified with various modifiers to reinforce the rubbers. The results show that the modification effect of coupling agent Si69 with 2. 5 phr is the best. The modified diatomaceous earth/rubber nano-composites were prepared by mechanical blending method. According to the mechanical properties tests, the more suitable diatomaceous earth reinforced rubbers were fluorine rubber (FKM) , ethylene-propylene-diene monomer rubber (EPDM) and acrylate rubber (ACM). And green environmental protection and low cost of diatomaceous earth can replace silica to reinforce and fill fluorine rubber, ethylene-propylene-diene monomer rubber and acrylate rubber.关键词：Modified-diatomaceous earth;Filler;Rubber;Composites;Mechanical properties
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发布时间：2022-09-06 - 摘要：A dual core salicylaldimine iron catalyst was synthesized by Schiff reaction and complex reaction with 1. OG dendric macromolecule, salicylaldehyde and iron chloride tetrahydrate as materials. The structure of the target product was characterized by FT-IR,1 H NMR, UV and MS. The influences of the kind of solvent, reaction temperature, reaction pressure, Al/Fe molar ratio and the types of metal active center on catalytic performance of ethylene oligomerization were researched with MAO as co-catalyst. The results showed that the catalytic activity of 1. 14 × 105g/(mol Fe• h) and 90% selectivity of C4 and C6olefins were obtained under the conditions that the toluene was used as solvent, the reaction time was 30min, the reaction temperature was 15 ℃ , the reaction pressure was 0. 5MPa,and the Al/Fe molar ratio was 1000.关键词：Dendritic macromolecule;Iron catalyst;Ethylene oligomerization;Catalytic activity
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发布时间：2022-09-06 - 摘要：The toughened bamboo flour/polylactic acid(BF/PLA) composites were manufactured by a melt blending method with acetyl tributyl citrate (ATBC) as plasticizers to improve the ductility of BF/PLA blends. Fourier infrared absorption spectroscopy (FTIR ),thermogravimetric analysis (TGA ),torque rheometer (TR ),scanning electronic microscopy(SEM) and mechanical test were adopted to study the addition of ATBC on the structure and properties of BF/ PLA biocomposites. The results showed that the addition of ATBC lead to an improvement in processing rheological properties and an reduction in glass transition, cold crystallization and melting temperature, but no Influence on the thermal stabilities of BF/PLA composites. The interaction between ATBC and PLA was confirmed by a small shift of C—O stretching peak in IR spectrum. The toughened BF/PLA composites with 15% content of ATBC showed an elongation at break up to 35. 6% , which was increased by 339. 5% compared with the BF/PLA composite without ATBC, and the fracture surface morphology was much rough and proved to be a typical tough fracture by SEM images at this condition.关键词：Poly(lactic acid);Bamboo flour;Biocomposites;Toughening;Acetyl tributyl citrate
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发布时间：2022-09-06 - 摘要："Polymer processing principles" is a core curriculum for the students majored in polymer materials processing. This course owns theoretical and practical characteristics, rich content and widely coverage. It is difficult for students to fully comprehend the curricular knowledge. The mode of traditional homework is completing the exercises just in the textbook with the interrogation reply way. By virtue of this simple way, it could hardly obtain a good teaching effect. Based on the need of teaching activity and the major feature on polymer processing, a test bank of polymer processing principles was constructed from the view of test content, types and knowledge levels. The test bank consists of homework, social practice subjects, periodical tests and experimental questions. An exercising mode with the feedback property between teacher and students combining the application of test bank was gradually formed. Compared with the learning effect of students, it is found that introducing the test bank was prone to clarify the knowledge mastery degree of students objectively, which was conducive for the teacher to adjust teaching contents. Moreover,the test bank could assist students to understand the key points of knowledge, apply the knowledge to solve practical problems and stimulate the research interest.关键词：Polymer processing;Test bank;Diversification;Feedback teaching
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发布时间：2022-09-06 - 摘要："Relaxation" is one of the most important concepts in the Polymer Physics courses. There are many derivative terms related to the term " relaxation", such as relaxation process,relaxation time spectrum, mechanical relaxation, dielectric relaxation, stress relaxation and secondary relaxation, etc. In this paper, these terms were brought together and interpreted respectively. Learners can understand these concepts very well so that they can no longer be confused by their similar names. Relaxation phenomenon is a macroscopic expression of the molecular motions in matter. In absolute sense,all the substances have relaxation phenomena. However, the relaxation phenomenon of the polymers is the most prominent among all the materials. The molecular mechanism of the polymer relaxation phenomenon is revealed.关键词：Polymer physics;Teaching research;Polymer;Relaxation
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发布时间：2022-09-06 - 摘要：This paper combined with the present situation of the undergraduate production practice at Zhejiang University of Technology and firstly discussed the problems existing in the current undergraduate production practice. Then, the college of materials science and engineering in Zhejiang University of Technology was chosen as an experimental unit to test the diversified forms of production practice based on "two systems four modernizations"training mode. The specific contents of the reform and practice included: based on the academy system as framework and tutorial system for the gripper, and the creation of production practice base corresponding to the professional characteristics, construction of the new small classed and personalized production practice mode and the reform of the student management mode and ratings. After three years of exploration and practice,it turns out that the undergraduates production practice reform implementation has achieved very good results.关键词：Undergraduate production practice;Two systems four modernizations;" Application-oriented engineering"talents
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发布时间：2022-09-06 - 摘要：In order to cultivate students' practical ability and scientific research ability, the college of Chemical and Materials Engineering of ChizhouUniversity reformed and integrated the polymer material experimental teaching system to construct the integrated project of polymer material processing and to carry out the teaching practice from four aspects : strengthening basic experimental teaching, optimization experiment project, strengthen students' subjectivity and relative examination system. The project strengthens the students' experimental operation skills,improves the participation of students in the scientific research projects; cultivates the students' scientific research ability. And achieves the targets set by the experimental teaching reform. Some problems are proposed in the practicing of project integration. The combination of teaching and scientific research is also proposed in the article.关键词：Polymer materials;Experimental project integration;Practical ability
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发布时间：2022-09-06
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