最新刊期
卷 27 ， 期 1 ， 2014
- 摘要：Due to low-cost, easily treated,and environment-friendly, water-based drilling fluid is usually the preferred drilling fluid. However, when it is used to shale,the problems of borehole instability, lost circulation,differential pipe sticking,and formation damage always may be caused. In order to solve these problems,nanoparticles are introduced into the water-based drilling fluid to obtain novel drilling fluid with improved properties. The present paper reviewed the water- based drilling fluid modified by nanoparticles. In terms of the type of the nanoparticles, the modified drilling fluid is divided into three types, organic nanoparticles, inorganic nanoparticles, and organic/inorganic nanoparticles modified drilling fluid. The three kinds of drilling fluid are discussed in detail. And the future developments of nanoparticles modified water-base drilling fluid are prospected.关键词：Nanoparticles;Water-based drilling fluid;Modified;The properties of drilling fluid;Shale
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发布时间：2022-09-18 - 摘要：Propagation in the cationic ring-opening polymerization of oxygen-containing heterocyclic monomers involves nucleophilic attack of oxygen atoms from the monomers on the cationic growing species. If hydroxyl groups containing compounds were present in the system, propagation may proceed with another mechanism which is known as activated monomer (AM) mechanism. For a long time,scholars' research focus mainly concentrated in the active chain end (ACE) mechanism, with the deepening of theoretical research and the development of testing technology, AM cationic polymerization of heterocyclic monomers was put forward. This review summarized the molecular mechanism of the existence of AM mechanism in the cationic ring-opening polymerization of oxygen-containing heterocyclic monomers. The paper also reviewed the chemical condition for initiating AM mechanism occurrence. Then, the AM mechanism was used as a tool to product block, star-like and hyperbranched polymers recently is summed.关键词：Oxygen heterocyclic;Cationic Ring-opening Polymerization;Activated monomer;Hyperbranched polymer
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发布时间：2022-09-18 - 摘要：Polysiloxane has many excellent properties, such as very low surface energy, excellent thermal stability, low temperature flexibility,good gas and water vapor permeability. The mechanical properties of polysiloxane is poor because of the weak intermolecular forces,which limited its applications in certain areas. Combining polysiloxane with organic or inorganic polymers by the technology of interpenetrating polymer network (IPN) can make up the defects of mechanical properties of polysiloxane as well as improve the properties of organic or inorganic polymers, such as surface property, transmission characteristic and flexibility, which makes IPN possess the unique properties of both. The research advances of main types of polysiloxane IPN and its applications were reviewed. The application prospect of polysiloxane IPN was also presented.关键词：Polysiloxane;Interpenetrating polymer network;Phase separation;Nanocomposite;Morphological structure
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发布时间：2022-09-18 - 摘要：With the full development and wide application of renewable green resources, cellulose derivatives are attracted more and more attention,and cellulose effective solvent cause widespread attention in the industry. Cellulose as the largest production in the nature of the polymer materials,reasonable utilization of cellulose is the most effective way to solve environmental and resource problems. Ionic liquids can dissolve well in cellulose, and it is also a good solvent of cellulose enzymatic hydrolysis reaction. Through the dissolution behavior of cellulose in ionic liquids, dissolution mechanism and degradation of cellulose enzyme action are discussed. The development prospects are proposed in the end.关键词：Ionic liquids;Cellulose;Cellulose enzyme;Dissolve;Degradation
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发布时间：2022-09-18 - 摘要：Preparation of flammable gas by biomass gasification in supercritical water is a novel energy conversion technology that be developed in recent years. There are many advantages for the method,such as high efficient, environmental friendly, and can make full use of renewable resources and so on, it is considered to be one of the most promising technologies, scholars at home and abroad have done a lot for it. In this article,the reaction paths and mechanisms of cellulose, hemicelluloses,lignin and their model compounds in sub-supercritical water without added catalysts have been reviewed. The co-gasification of biomass and their model compounds also has been discussed. Trends of the new method in the future were pointed out.关键词：Biomass;Supercritical water;Gasification;Mechanism
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发布时间：2022-09-18 - 摘要：In recent years, many researchers tried to that carbon nanotubes (CNTs) doped liquid crystal composite material were synthesized with excellent property by physical or chemical method, that were orderly organic/inorganic hybrid. The hybrid system shows in addition to the nature of the component itself,more due to the interactions between them and shows new characteristic. At present, the main direction of research is through the doping nanometer materials to improve the liquid crystal material performance. In this paper,research progress of CNTs doping liquid crystal composite materials was discussed. According to the ferroelectric liquid crystal, the nematic liquid crystal, discotic liquid crystal and liquid crystal polymer, effect on the phase transition temperature of the liquid crystal,and photoelectric properties and conduction properties of the composites was briefly introduced.关键词：Carbon nanotube;The ferroelectric liquid crystal;The nematic liquid crystal;Discotic liquid crystal;Liquid crystal polymer
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发布时间：2022-09-18 - 摘要：Wide angle X-ray diffraction (WAXD) was applied to study the Hermann orientation factor and crystallinity of PAN nascent fiber obtained by dry jet wet-spinning and wet-spinning methods,respectively. Based on the azimuthal scan results,it was indicated that with the increasing of shear rate and drawing ratio, the Hermann orientation factor of the nascent fiber gradually improved. At the same shear rate and drawing ratio,compared with the nascent fiber made by dry jet wet-spinning, the orientation factor of the nascent fiber produced by wet spinning is higher. During the dry jet wet- spinning process,the crystallization was occurred under weak stretching since the drawing force was focus on the soft part in air layer. Therefore, the Hermann orientation factor was reduced. However, in the wet-spinning process,the crystallization occurred immediately after extrusion,the drawing force induced the increasing of the orientation for crystalline region. The model for the evolution of the aggregation state of PAN molecular chains was proposed.关键词：PAN nascent fiber;Dry jet wet-spinning;Wet-spinning;Hermann orientation factor
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发布时间：2022-09-18 - 摘要：Modified polyvinyl alcohol (PVA) were prepared by mixing PVAc(03) with low degree of polymerization (low DP) and PVAc (17) with high DP into methanol and then adding appropriate lye into the solution to proceed alcoholysis. The effect of PVA (03) on modified PVA was studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD). The results showed that when the concentration of PVA(03) was less than 10%,the melting point and degree of crystallinity of modified PVA were slightly changed but the solubility in water was largely improved. This was because PVA (03) come into amorphous region, when polymer contacted with water, PVA (03) first dissolved in water, after the PVA(03) dissolved, it formed a hole in the polymer,so the solubility of PVA(17) was largely improved..关键词：Poly (vinyl alcohol);Low DP;Modified;Solubility
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发布时间：2022-09-18 - 摘要：By changing the activated and modified conditions such as calcining temperature, coupling agent, calcining time on the fly ash to study the best activated and modified conditions. The properties of vulcanization and physical and mechanical were measured. The results show that high temperature calcing can help the reinfrocing properties to natural rubber(NR) but not obviously. Combined the fly ash with different proportions of carbon black (CB),when the quality ratio of carbon black reaches ≤ 20%, tensile strength of NR will increase obviously as the increment of ratio of carbon black. When the quality ratio of carbon black reaches >20%,the improvement rate of property of NR vulcanizes would be dropping. But when the weight ration of CB reached to 50 %, 300 % modulus of NR vulcanizes is close to pure CB reinforced NR.关键词：Flyash;Modification;Natural rubber;Reinforcing properties
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发布时间：2022-09-18 -
Preparation and Fluorimetry Mechanism of Molecularly Imprinted Polymers Microspheres for Rhodamine B
摘要：Molecularly imprinted polymers (MIPs) were prepared by a one-step swelling polymerization method in aqueous system using nano-polystyrene microspheres which was gained by dispersion polymerization as seeds and using Rhodamine B as template molecules. The infrared spectrometry(IR) of the polymers further indicated that there were some functional groups in the MIPs which could interact with the template. The binding mechanism and identification characteristics of MIPs were evaluated by ultraviolet spectrometry. Morphological characterizations of the MIPs were tested by scanning electron microscope (SEM); The adsorption ability and fluorescence characteristics were evaluated by fluorescence spectrophotometry. Results show that the diameters of PS microspheres were between 100 〜150nm and the diameters of MIPs were between 200 〜300nm. Rhodamine B molecularly imprinted polymer of Rhodamine B molecules with specific recognition selectivity and excellent combination of properties The maximum excitation wavelength and the maximum emission wavelength were 557 nm and 593 nm.关键词：Molecularly imprinted polymers;Single-step swelling polymerization;Rhodamine B;Fluorescence spectrophotometry- 2
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发布时间：2022-09-18 - 摘要：Basalt fiber is an ideal reinforcing material for rubber based composites and shows good prospect in high- strength, high temperature,alkali/acid resistance,ablation resistance,abrasion resistance,and other special areas,it have great development value in thermal protection,anti-bomb, anti-corrosion pipes,linings, etc. According to the similar structures and properties of basalt fiber and glass fibber,the properties of basalt fiber,research status at home and abroad on the basalt fiber composites, basalt fiber rubber composites preparation process and studies on basalt fiber reinforced rubber composites, were introduced. The development trend of basalt fiber reinforced rubber composites was previewed.关键词：Basalt fiber;Rubber;Composite materials;Research status;Progress
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发布时间：2022-09-18 - 摘要：Polycarbonate (PC) is one of the most widely used engineering thermoplastic owing to excellent physical and chemical properties. However,environment factors such as light, oxygen,temperature and humidity result in changes of the performance of polycarbonate. In order to improve performance of anti-aging of polycarbonate materials,it must be completely understood the mechanism of the aging process,and then purposefully modified. Three polycarbonate material aging reaction mechanism of physical aging,light oxygen aging and thermal oxygen aging are analyzed in this paper. At the same time,the structure and properties of polycarbonate changes caused by aging changes are introduced. Finally the paper also reviews the new progress of polycarbonate aging behavior research in recent years and a new interpretation of classical theory, puts forward future research direction at the same time.关键词：Polycarbonate;Physical Aging;Ultraviolet aging;Thermal aging
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发布时间：2022-09-18 - 摘要：In copolymerization reaction of two monomers, reactivity ratios r1 and r2 may vary in a wide range. Thus, correspondingto the different values, there are diverse kinds of the F1 —f1 curves. In most textbooks, the first step of the classification process is to compare the product of r1 and r2 (r1 • r2) with the value 1. However, this indirect classification method might be opaque to some beginners. This article will provide a novel and fundamental strategy directly based on r1 and r2 value per se,followed by the discussion of diverse systems. We hope the classification could be helpful to polymer chemistry education as well as the frontier research.关键词：Copolymerization;Reactivity ratio;Ideal copolymerization;Alternating copolymerization
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发布时间：2022-09-18 - 摘要：A software,which can demonstrate binary copolymer composition curves of polymer chemistry,is programmed via using Matlab. The visualization of copolymer composition, including instantaneous copolymer composition, average composition and segment sequence distribution,can be achieved only by inputting the reactivity ratio or Q and e values. This software is simple enough to be used, which not only can be used for classroom teaching but also can be practiced by the students after class. It is a powerful computer-assisted instructive tool.关键词：Polymer chemistry;Copolymer composition curve;Visualization;Matlab software
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发布时间：2022-09-18 - 摘要：Specialized courses teaching is the key link of the university education and the main channel to cultivate students' learning ability and good psychological quality. As the first specialized course of polymer major curriculum system, importing psycho-education elements in polymer chemistry course teaching practice has a great influence on students to establish professional identity and is very important to cultivate the students' healthy psychological quality and good professional accomplishment. Some experience in my polymer chemistry teaching practice using the psychological education from the arousing and cultivating of learning interest, using incentive mechanism,enhancing students' self- confidence and reforming the evaluation mechanism has been took about in this article.关键词：Psycho-education;Polymer chemistry;Learning interest;Incentive mechanism
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发布时间：2022-09-18
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