最新刊期
卷 25 ， 期 10 ， 2012
- 摘要：With the rapid development of the microelectronics industry, the insulating interlayer material with low dielectric constant is urgently needed in order to improve the speed of transmission between the chips of large scale integrated circuit and meet the requirement of high integration. Polyimide is widely used as the insulating interlayer material in large scale integrated circuit. Reducing dielectric constant of polyimide has attracted much research attention in recent years. When using chemical methods to reduce the dielectric constant, modifying the molecular structures of polyimide is a basic approach. On the other hand, building the porous structure in materials is an effective way to further reduce the dielectric constant of polyimide. In this paper, the recent developments in modifying the molecular structure and building the porous structure are reviewed. Preparation methods of polyimide with low dielectric constant by both methods are summarized and the research prospects in this area are predicted.关键词：Polyimide;Low dielectric constant;Porous;Molecular structure
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发布时间：2022-09-18 - 摘要：The scaffolds play an important role in providing growth, multiplication and metabolization environment for cells in skin tissue engineering. The scaffolds also guide tissue regeneration and control the structure of tissue as templates. To explore the ideal scaffold, materials is one of the popular studies on current skin tissue engineering. Thus, the research progress of the skin tissue engineering scaffolds in recent years was reviewed. It included three categories: natural scaffolds, synthetic scaffolds and composite scaffolds. The preparation and application of these scaffolds were also discussed, with analysis on some problems existing in skin tissue engineering scaffolds and its developing trend in the future.关键词：Skin;Tissue engineering;Scaffolds
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发布时间：2022-09-18 - 摘要：As a important way to synthesize biopolymer described by many researchers, lignin can be used to replace with phenol to prepare phenolic resin after active modification due to the similar structure to phenol. The lignin-modified phenolic resin can not only resduce the cost but also achieve the purpose of utilization of biomass resources. It has lower toxic residue with environmental importance. In this paper, the latest progress in study of phenolic resin adhesive modified by lignin was reviewd. Especially, the chemical, physical, biological methods for lignin active modification was described by showing the porpertis of adhesive with comparing them. After analysis in technology difficulties, it is summarized the main factors affected feasibility of the industrial application of phenilic resin adhesive modified by lignin.关键词：Lignin;Modified;Phenolic resin;Adhesive
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发布时间：2022-09-18 - 摘要：Diseases of blood vessel have become the leading cause of death in the worldwide. However, the supply of autologous blood vessel may not be sufficient and an immune response exist for xenogenic blood vessel. More attention is focused on tissue engineering blood vessel in borne and abroad. In order to satisfy the demand for vessel scaffold in the region of the clinic, the material of the scaffold and the modification of the scaffold’s surface should be considered. Another important point is the fabrication process of scaffold. By now, electrospinning, phase separation process, self-assembly, gel spinning, rrapid prototyping are the main technology to prepare tissue engineering tubular scaffold. In this paper, the research development of the tissue engineering tubular scaffold prepration technology was summerized.关键词：Tissue engineering;Tubular scaffold;Blood vessel
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发布时间：2022-09-18 - 摘要：Graphene has attracted great interest for its outstanding mechanical,thermal,electrical and optical properties since it was found in 2004.Lots of polymer composites,based on graphene,were prepared and characterized,these researches show that the mechanical,electrical thermal and optical properties of polymer composites could be improved obviously for the addition of graphene.In this article,the research progress of graphene-based polymer composites was summarized.Especially,the preparation methods and properties of graphene-based polymer composites were described.The applications in biomedical science,solar cell and super-capacitor were introduced,and the developing trends and applying prospects of graphene-based polymer composites were also described.关键词：Graphene;Polymer composites;Progress
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发布时间：2022-09-18 - 摘要：In this paper,the progresses of shape memory polymer materials of poly lactic acid are reviewed.The shape memory effects and memory mechanism of polymer materials are introduced.In terms of the different components,the shape memory polymer materials of poly lactic acid can be divided into three types,polymers based on poly lactic acid,based on poly lactic acid copolymers and based on poly lactic acid/inorganic materials.The behaviors of memory effects and biodegradation are discussed.Finally,the applications of poly lactic acid are introduced and the future developments of the polymer materials are prospected.关键词：Shape memory polymer;Poly (lactic acid);Biodegradation
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发布时间：2022-09-18 - 摘要：Polyhedral Oligomeric Silsesquioxane (POSS) are hybrid organic-inorganic nanoparticles with a 3D cage structure,i.e.,by a polyhedral Si—O—Si nanostructured skeleton,surrounded by several organic groups linked to silicon atoms by covalent bonds which have high designability and high reactivity.Variety of POSS-Polymer hybrid materials can be prepared by selecting specific optical,electrical,magnetic and other characteristics of the unit through living polymerization method.Long range ordered nanometer structure materials are obtained by "combing" structure of molecular chain through solvents,heat,electricity,and the nanoprinting methods,obtaining the expected sequence,structural and functional polymers.This article introduces the self assembly of amphiphilic POSS hybrid polymer materials,analyzes the latest advances in research of the biological medical polymer,intelligent polymers and electro-active polymer materials,forecasts and prospects the development in the future.关键词：POSS;Amphipathic polymer;Slef-assembley;Functional polymer
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发布时间：2022-09-18 - 摘要：In order to study how fiber chemical properties affect the adsorption of harmful compounds of thread embedded in cigarette filter.Boehm titration,FT-IR,cigarette smoke routine analysis,and amounts of harmful compounds released in cigarette mainstream smoke analysis were taken into consideration.Results showed that: 1) amounts of NH3 in mainstream smoke reduced with fiber acidity increasing;and HCN reduced with fiber total basic groups increasing;2) amounts of phenol in mainstream smoke was effected mainly by the quantities of lactone groups on fiber,and subsidiary effected by the acidity of fiber;3) amounts of crotonaldehyde reduced with amino groups of fiber increased.关键词：Boehm titration;FT-IR;Fiber chemical properties;Routine analysis;Harmful compounds
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发布时间：2022-09-18 - 摘要：A charge partition complementary theory of polyelectrolyte multilayer films having the linear growth via layer-by-layer self-assembly was put forward. The theory are used to study a semi-empirical mathematical model about the relation between charge overcompensation, induced charge, polyelectrolyte adsorption amount and conformation, forms of intra-film charge and charge density. The ionization rate of polyelectrolyte inside multilayer film and the induced charge can be calculated deriving this model. The ionization rates of the outer layer and the outermost polyallylamine hydrochloride were discussed. The method is simpler and more convenient than the infrared spectrometry method and photoelectron spectroscopy method. The ionization rates of all polyelectrolytes can be researched using the method.关键词：Polyelectrolyte;Layer-by-layer self-assembly multilayer;Charge partition complementary;Ionization;Overcompensation
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发布时间：2022-09-18 - 摘要：A new-type gradient nuclear radiation shielding material was prepared for utilizing Lu2O3,tungsten and polyethylene as main raw materials by mechanical blending method handled with coupling agent,acid and alkali reaction method and in-situ reaction.Afterwards hot-press processing and layered hot-pressing superimposition was used to process materials and then gradient materials were obtained.At last,monolayer and gradient materials were characterized and tested.The results indicated that: the new gradient material had good tensile properties.Meanwhile,beta and gamma rays could be shielded well,it oneself had lead-free poison,the lasting shielding effectiveness,the good comprehensive shielding performance,and it could flexibly adjust the types and the order of monolayer materials for getting corresponding gradient materials according to the specific radiation environment.The gradient materials had a good application future.关键词：Nuclear radiation;Rare earth;Gradient;Composite;Shielding
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发布时间：2022-09-18 - 摘要：With the advancement of science and technology,materials science has greatly developed.Especially,the development and application of polymer materials are considerably fast.The relationship between structure and properties in the new application environment has to be studied for many polymer materials.Therefore,it is very necessary to understand the variation of structure and properties of these polymer materials under some extreme conditions(high temperature and pressure,low temperature and pressure et al.).The structure and property of polymer materials are significantly affected by high pressure.A series of studies have been made on the crystallization and annealing of polyolefin,polyester,polyamide and so on under high pressure by scholars from home and abroad.A review of research progress in this filed is introduced in this paper.关键词：High pressure;Polymer;Crystallization under high pressure;Annealing under high pressure;Extended-chain crystals
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发布时间：2022-09-18 - 摘要：This paper reviewed breakthroughs in compatibilizer field,including the development of compatibilizer systems and compatibilization characterization techniques.This paper reported several novel compatibilizer systems like PVDF-g-AAc-g-TPU,EAGMA,PP-g-MAH and PP-g-MAH-St,which overcome the weakness of thermal stability among polymer blends and polymer-based composites,decrease the processing temperature and increase the tensile/impact strength.Other hand,modern characterization techniques promotes the research on effects of compatibilizer systems and compatibization of blends,this paper reported the Haake rheometer and DSC curves on compatibilizers’functional groups,the SEM and TEM images on fracture morphology and average size of EMG compatibilized MDPE/PET and POM images and WAXD curves on crystallization behaviors characterization of crosslinked LLDPE-PP/LLDPE/PP.In addition,this paper discussed the disputes concerning the effects of compatibilizers on polymer blends and proposed that compatibilizers will become composited and multifunctional.关键词：Polymer alloys;Compatibility;Properties tests;Characterization techniques
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发布时间：2022-09-18 - 摘要：Classroom teaching in university,especially basic theoretical teaching,is difficult to attract students,and the teaching effect is not good enough.In this paper,the author’s teaching experience is taken as an example and the process of interactive teaching about"statistical significance of molecular weight"is recorded in detail.In the interactive teaching,teacher is facilitator and students are actors.Based on the students’situation and the student-oriented principle,explanations,discussions and exercises are combined.Knowledge spot can be easily accepted by students through this teaching method.Compared with the method that the knowledge spot was only explained by teacher,the number of students joining the course action was improved markedly.关键词：Interactive teaching;Classroom teaching;Molecular weight in polymer
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发布时间：2022-09-18 - 摘要："Multi-module and three-dimensional"practice teaching system was related to the quality of personnel training and played an important role in the building of an innovative country of China.In this article,the status of higher education practice teaching system was analyzed and the"multi-module and three-dimensional"practice teaching system was constructed and implemented based on the background of this teaching system.It was pointed out that the traditional experimental teaching system of local colleges and universities was unable to meet the need for innovative practice personnel training,the concepts of teaching should be updated,the experimental teaching system and content should be reformed,the open experimental center should be created,and the designing,researching experiments should be vigorously promoted.关键词：Practice teaching system;Local colleges and universities;Multi-module and three-dimensional;Reform;Implement
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发布时间：2022-09-18 - 摘要：Polymer composite course is one of the elective courses for the postgraduate with the background of polymer materials,the teachers group tried to reform the teaching methods through three ways.First,visualized teaching and inter-communication were applied to track the attention of the postgraduate students and improve the interest of studying.Second,case studies based on the research background of teachers groups were shared with the postgraduate students,which made the teaching more vivid. Third,the postgraduate students were encouraged to reading,analysis and re-arrange the literatures and prepare academic lectures,which help the postgraduate students to feed themselves,more than being feed.In recent years the teaching practice shows that these reform measures have received the good effect.关键词：Polymer composite course;Course for postgraduate students;Teaching reform
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发布时间：2022-09-18
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