最新刊期
卷 30 ， 期 2 ， 2017
- 摘要：Organic solar cells(OSCs) with the typical sandwich structure use the conjugated organic materials as the active layer to convert sunlight into electricity through the two electrode outputting current. These organic materials have the advantages of wide source, lightweight and renewable, causing that OSCs have attracted much attention in the field of clean renewable energy. The present research focus is still to enhance the power conversion efficiency (PCE) of OSCs mainly by improving the active layer materials, optimization of device structure and interfacial modification and so on. This paper mainly introduces the efforts of our group in interfacial engineering. We demonstrated highly efficient OSCs by incorporating the sulfonic acid or carboxylic acid functionalized hyperbranched polymers to modify the cathode interface. We reported the novel non-conjugated small molecule electrolytes as the interfacial layer for efficient OSCs to achieve high PCE up to 10.02% in single heterojunction conventional OSCs. We found that simple polar solvent treatment such as methanol could optimize morphology of the active layer and enhance the performance of the devices.关键词：Organic solar cells;Interfacial engineering;Hyperbranched polymers;Non-conjugated small molecule;Polar solvent
- 9
- |
- 10
- |
- 1
发布时间：2022-09-06 - 摘要：Uniform size polystyrene-divinylbenzene microspheres,a kind of functional polymer material has been widely applied in many industries, which have many excellent features, such as good physical and chemical stability, high mechanical strength, and high reactivity of benzene ring. Besides their functional products have great application value in various fields.The preparation methods of uniform size polystyrene-divinylbenzene microspheres were reviewed, including suspension polymerization of spraying, the technology of porous cross-flow membrane, the technology of orifice dispersion polymerization, the effects of droplets’ size and the microspheres’ particle size were described and analyzed, advantages and disadvantages of these methods are summarized. Finally, the prospects for the development of uniform size polystyrene-divinylbenzene microspheres were forecasted.关键词：Polystyrene-divinylbenzene microspheres;Preparation methods;Uniform particle size
- 5
- |
- 12
- |
- 0
发布时间：2022-09-06 - 摘要：Traditional fossil plastics has brought a lot of convenience to human, but these refractory plastic are continuous accumulating in the environment, leading to the deterioration of global environment, the solid waste disposal problems. Therefore, the research and development of biodegradable plastic has become the main point in recent years. Polyhydroxyalkanoate (PHA), a microbially synthesized polyesters with good biological degradability, biocompatibility and other special properties, can become the new biological materials alternative to traditional fossil plastic. Also PHA, as a heart valve tissue material, has achieved very good results in animal trials. It has shown good environmental effects and some promises. In this paper, the microorganisms in synthesis of PHA and their fermentation technology were reviewed combining with synthesis of PHA related research at home and abroad, then its development is prospected.关键词：Polyhydroxyalkanoate;Microorganism;Fermentation
- 10
- |
- 10
- |
- 1
发布时间：2022-09-06 - 摘要：Polyimides are a kind of high-performance functional material which is widely used in various fields, but low refractive index limits its application in the field of optics. By introducing aromatic ring substituents, sulfur atom in the main chain and inorganic particles hybrid modification method many researcher can effectively improve the refractive index of the polyimides. This article describes the latest research progress both in domestic and overseas that some research team prepared high refractive index of the polyimides, then concludes that the method of increasing the refractive index of polyimide can be divided into the following ways:introducing sulfur atom into the main chain of polyimide; mixing the inorganic particles to modify the polyimide; developing a new synthesis route. The synthetic route of the several methods and the properties of the resulting products were reviewed and point out the general tendency of the synthesis of high refractive index polyimides.关键词：Polyimide;High refractive index;Synthetic method
- 7
- |
- 12
- |
- 1
发布时间：2022-09-06 - 摘要：The amphotericpH sensitive gel possesses both the ionized acidic group and the basic group.Compared with the conventional gel, it has better swelling properties and biocompatibility.It is widely used in many aspects such as biomedical science, drug delivery systems, micro-fluid control and so forth.However, there is still a lack of the FEM method for the amphoteric pH sensitive gel.Therefore,we use the equilibrium swelling theory of amphoteric pH sensitive gel,andFEM methodwhich is developed to describe the mechanical behavior of gel swelling,to calculatemechanical behavior of pH sensitive gel in homogeneous and inhomogeneous swelling.The results shows a very good agreement between results of FEM calculation and the analytical solution of the gel swelling theory.It can provide important parameters and mechanical theoretical guidance for some key indexes in biology,and also provide an important reference for the design of micro fluid control valve.关键词：Amphoteric pH sensitive gel;Swelling theory;Free energy of gel;FEM
- 5
- |
- 9
- |
- 0
发布时间：2022-09-06 - 摘要：A novel cationic hydrogel bead with high adsorption capacity was prepared by solution polycondensation and inverse suspension polymerization using formaldehyde, acetone and triethylenetetramine as raw materials. The chemical structure and surface morphology of the hydrogel bead were characterized. The adsorption behavior and mechanism of hydrogel bead for anionic dye Acid Black 10B and surfactant sodium dodecyl benzene sulfonate (SDBS) from aqueous solution was investigated via batch experiments. Experimental results showed that cationic hydrogel bead had high cationicity and abundant polar functional groups. The adsorption was attributed to a combination of electrostatic attraction and intermolecular interactions, such as hydrogen bonding, and the adsorption efficiency increased with decreasing solution pH. During the adsorption, adsorbate molecule permeated into the bead and then was adsorbed onto the inner surface of the hygrogel. Therefore, the adsorption process was governed by the diffusion of the adsorbates inside the hydrogel matrix, which enabled a high adsorption capacity.关键词：Cationic hydrogel bead;Solution polycondensation;Inverse suspension polycondensation;Adsorption
- 3
- |
- 10
- |
- 0
发布时间：2022-09-06 - 摘要：In order to analyze the influence of density on photo-oxidation degradation properties of polyethylene (PE), the materials parameters (mechanical properties, thermal stability, melting characteristic, chemical structure and surface morphology) of different density polyethylene including high, low, linear low and medium density polyethylene (HDPE, LDPE, LLDPE and MDPE) were studied by mechanical experiments, gel permeation chromatography (GPC), thermogravimetry analysis (TGA), differential scanning calorimetry (DSC), attenuated total reflection infrared spectroscopy (ATR-FTIR) and scanning electron microscope (SEM). The results show that LDPE resulted in the decreased faster in the bending property, thermogravimetry analysis characteristic temperature and oxidation induction temperature mainly concentrated in the early part of aging. After 24 days of aging, the impact strength of HDPE and LDPE decreased. After 64 days of aging, the molecular weight of different density polyethylene decreased and the variations of weight average molecular weight of LDPE decreased more intensely. The degree of unsaturation of LDPE and LLDPE increased significantly and there were no obvious differences in the variations of chain branching of the different density polyethylene. The variations of chain breaking, oxidation, carbonyl index, hydroxyl index and surface morphology of LDPE were more significantly and severe. The branch breaking the regularity leaded that LDPE was prone to aging.关键词：Polyethylene;Photo-oxidation aging;Comparative research;Degradation properties;ATR-FTIR
- 5
- |
- 13
- |
- 4
发布时间：2022-09-06 - 摘要：The structure and physicochemical properties of waxy maize starch in a fluidized bed opposed jet mill were studied in this paper. The granular morphology, crystal texture and physicochemical properties of it were further characterized using scanning electron microscopy, laser particle size analyzer, X-ray diffractometry, infrared spectrometer, differential scanning calorimetry, rapid visco analyzer. The results show that micronized waxy maize starch granular median diameter is decreased 6.43μm, starch granules lose smoothness on surface and become rough. The crystal structure of waxy maize starch is a-type structure and is changed from polycrystalline to amorphous and is no new groups produced. Enthalpy and gelatinization point all is decreased and has a better viscosity stability. Compared with native starch, all other property factors of micronized waxy maize starch, such as the water binding capacity and freeze-thaw stability are significantly increased. Its hot paste stability and mechanical stability are better than those of native waxy maize starch.关键词：Jet mill;Waxy maize starch;Structure;Physicochemical properties
- 5
- |
- 9
- |
- 1
发布时间：2022-09-06 - 摘要：This paper described a novel synthetic methodology towards epoxidized trans-1,4-poly isoprene (ETPI), using a self-made oxidation reagent. Results showed that the addition of appropriate amount of ethyl acetate or chloroform to the reaction system could improve the degree of epoxidation. Epoxy degree as high as 32% in ethyl acetate, and 51% in chloroform could be obtained. Compared with the traditional method (using the peroxide or acetic acid as the oxidant), the new synthetic method greatly suppressed the side reactions such as over oxidation, chain scission and furan ring formation, which in turn greatly improved the mechanical properties of the resulting ETPT. Mechanical tests shows that the raw ETPI prepared using this novel method shows a tensile strength over 20 MPa, almost 7 times stronger than ETPI prepared using traditional method. Improved wet-skid resistance was observed with the increase of epoxy degree for ETPI prepared using the new method, while rolling resistance changed little. Oil resistance tests showed that the oil resistance of ETPI was significantly increased when the epoxy degree was greater than 15%.关键词：Epoxidation;Trans-1;4-Polyisoprene;Epoxidized trans-1;Wet-skid resistance;Oil resistance
- 5
- |
- 12
- |
- 0
发布时间：2022-09-06 - 摘要：By using Cone Calorimeter(CONE) and thermogravimetric analysis (TGA), limiting oxygen index (LOI) and vertical burning test (UL-94), the flame retardance and thermal degradation behaviors of polypropylene(PP)-ethylene-vinyl acetate copolymer(EVA) composite filled core-shell nanoparticles(CSN) with polystyrene (PSt)/organophilic montmorillonite (OMMT) as core and poly(butyl acrylate) (PBA) as shell and its flame retarded composites prepared of PP-EVA/ammonium polyphosphate(APP)/layered double hydroxide(LDH) by additions of non-halogen mixture as flame retardants were studied. The results showed that adding 10%(wt) CSN could improve the flame retardancy of PP-EVA composites, decrease the heat release rate and the effective heat of combustion, increase thermal stability of PP-EVA composite. CSN had a little better synergistic flame retardant effect with APP/LDH, which can further built up flame retardancy and thermal performance.关键词：Core-shell composite;Polypropylene;Ethylene-vinyl acetate copolymer;Flame retardance;Combustion behavior
- 6
- |
- 9
- |
- 0
发布时间：2022-09-06 - 摘要：Conformation statistical theory of polymeric chains is essential to the understanding of the concept of Gaussian chain. It is the base of the statistical theory in polymer science. Kuhn’s method is the mostly described one in textbooks of polymer physics. But the mathematical steps are complex, which is hard to be comprehended by the students. Meanwhile, some flaws exist in it which hinders the understanding of the concept of Gaussian chain and has a negative impact on the study of statistical theory of polymer dilute solution and rubber elasticity. The Kuhn’s method is modified based on central limit theorem. Two methods for calculating the mean square end-to-end distance are introduced. These methods are concise and explicit, which are easy to understand and be beneficial for the students to catch on the concept of Gaussian chain.关键词：Gaussian chain;Mean square end-to-end distance;Statistical algorithm;Central limit theorem
- 6
- |
- 10
- |
- 0
发布时间：2022-09-06 - 摘要：Thorough knowledge lecture mode on polymer materials is combined the basic knowledge, major knowledge and practical knowledge together. The methods and steps of thorough knowledge lecture mode based on the polymer modified asphalt by reactive processing are introduced. The deep understanding polymer materials and the ability of analyzing and solving problems was improved obviously through reading references, designing experiment, carrying out experiment and practicing in real project. This lecture mode is good for the graduates and undergraduates mastering the kernel of polymer engineering and science, selecting the interesting research, orientating the job career and meeting the requirement of society. It is also significant to nurture the comprehensive quality and to improve the innovation and entrepreneurship spirit of students.关键词：Polymer materials;Thorough knowledge lecture;Experimental case;Innovation;Entrepreneurship
- 10
- |
- 10
- |
- 1
发布时间：2022-09-06 - 摘要：In this paper, the diversified reform of polymer comprehensive experiment was proposed according to the current situation and existing problems of this course discussed in details in the front of the paper. One diversified reform example of polymer comprehensive experiment was designed combining the feature of major in our school and carried out. The results of this example were analyzed. In this diversified polymer comprehensive experiment, the knowledge of various materials, processing methods and the influence of elastomer and filler on different polymers was studied using comparison method. Besides, the students also got the ability to understand and operate the many advanced apparatuses used in this experiment. The diversified comprehensive experiment not only improved the understanding of theoretical knowledge, but also enhanced the students’ abilities of operation, thinking and solving the problem, which was important for the following graduation practical teaching and working. In addition, different distinctive polymer comprehensive experiment could be formed by diversified reform according to this paper, different school characteristic and class hour of this course along with training the high quality graduation students.关键词：Diversification;Polymer;Comprehensive experiment;Reform
- 6
- |
- 10
- |
- 1
发布时间：2022-09-06
- Technical support is provided by Beijing Founder electronics co., LTD 京ICP备09064830号-19
京公网安备11010802024621 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
0