最新刊期
卷 26 ， 期 12 ， 2013
- 摘要：The hot topics, the examples of research progress were briefly introduced. The funding program in polymer science of National Natural Science Foundation of China in 2013 was summarized. Additional remarks on the mistake, misreading and misconception in preparing proposals were given. The guidance for grants in 2014 fiscal year in division of polymer science of Department of Chemical Science was released.关键词：Funding programs National Natural Science Foundation of China;Progress in polymer science in China;Guidance of grants for 2014
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发布时间：2022-09-18 - 摘要：Organophosphate salt typed nucleating agent is of good performance on nucleated poly(propylene)(PP). The crystallization temperature of PP containing organophosphate salt(such as sodium 2,2’-methylene-bis-(4,6-di-tert-butylphenyl)phosphate) is increased remarkably, and the properties including thermal distortion temperature, rigidity and especially transparency of PP products can be improved significantly. Therefore, it attracts a lot of interests of many researchers devoting to the development of this typed nucleating agent. Research about nucleation mechanism will provide a theoretical basis for designing new and highly efficient nucleators in the future. However, by far, nucleation mechanism concerning to organophosphate salt on PP has not been illustrated clearly. Two explanations have been proposed on how nucleating agent accelerates nucleation. The most popular one insists that "epitaxy" between nucleating agent and polymer crystals controls the nucleation. The other one insists that suppression of mobility of molecular chains by adding nucleating agent controls the nucleation. The focus of this review is on the progress of nucleation mechanism of nucleators on PP, with special emphasis given to the development of nucleation regularity and mechanism of organophosphate salt typed nucleating agent on PP. The future prospect of nucleation mechanism is foreseen in the last.关键词：Organophosphate salt;Nucleating agent;Polypropylene;Nucleation mechanism;Epitaxy
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发布时间：2022-09-18 - 摘要：Nowadays, commerically used fiber filtering materials are woven fabric, knitted fabrics and nonwoven materials. The electrospun nonwoven filtering materials have the high specific surface area, high porosity and high pore permeability compared with the traditional fiber filtering materials. They are more easy to separate small particles and they can be used as filtering materials for high precision and high performance. Thus, they have a wide range of applications. In this paper, the research development of electrospun nanofiber preparation and applications has been reviewed. The emphasis is focus on the electrospun nanofiber used as fiber filtering materials in ions-adsorption, aerols filtration and liquid filtration. At the same time, the application of the electrospun nanofiber in special filtration such as anti-bacterium filtration and high-temperature filtration has been introduced. In the end, the prospect of electrospun nanofiber filtering materials has been proposed.关键词：Electrospinning;Nanofiber;Filtering materials
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发布时间：2022-09-18 - 摘要：This paper introduces the research status of cement based composites doped with such as poly (vinyl alcohol), polypropylene, polyacrylonitrile and polypropylene mesh fiber. The results show that the mechanical properties of cement based composites have improved significantly doped with fibers,in which polypropylene plays an important role in enhancing high temperature resistance and anti-burst performance, polyacrylonitrile fiber can inhibit contraction effectively, steel fiber can improve its resistance to impact and tensile properties, in addition, polyvinyl alcohol fiber has advantage in promoting its early crack resistance. In conclusion, compared with single fiber, composite fiber cement-based materials may get better performance.关键词：Cement based composites;Fiber;Dope;Property
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发布时间：2022-09-18 - 摘要：As the sustainable resource, wood is ideal for indoor and outdoor construction and decoration. However, wood is flammable and greatly influenced by the environment. Modification of wood has long been widely concerned and it is nowadays the common concern of material scientists and chemists to explore environmental-friendly methods of wood modification. Inorganic materials, with the characteristics of non-toxic and simple preparation, can not only keep the environmental merits of the wood to the most degree, but also improve many properties of wood. Sol-gel technique, a wet chemistry approach, was developed two decades ago for the preparation of inorganic materials and their coatings, and can be used for wood modification effectively to obtain wood/inorganic composites. In this review, we give an overview of the mechanism and characters of sol-gel modification of wood and the improvements of wood properties after sol-gel modification, including flame-retardant, antibacterial, water proofness, anti-UV and mechanical properties. We also look into the future trends in the field.关键词：Wood;Sol-gel;Modification;Wood/inorganic composites
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发布时间：2022-09-18 - 摘要：With the development of green chemical engineering, 1-octene prepared vis ethylene tetramerization is Atomic economy’ reaction. It has an advantage of high selectivity and low energy consumption, which have attracted considerable attention in the academic and industrial field. In this paper, the latest progress of ethylene tetramerization to 1-octene has been summarized from ligand, cocatalyst, solvent and the reaction mechanisms.关键词：Ethylene tetramerization;1-Octene;Chromium-based catalyst
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发布时间：2022-09-18 - 摘要：Electrospinning is a high efficient spinning technology for preparing nanofibers. The elecstrospun membrane could provide several extensive functional characteristics such as high specific surface area, large porosity and three-dimensional pore channel. Now, the kinds of polymer and inorganic/polymer nanofibers could be prepared through electrospinning technology. It is possible to applicate in the water filter, tissue engineering scaffold, and electronic sensor. In this paper, we introduced the process of electrospun composite membrane systematically, including the method of casting, chemical cross-linking, sol-gel and others. Further more, we analyze the effect on electrospun membrane morphology, because it will affect the applications mentioned above.关键词：Electrospinning;Nanofiber;Composite membrane;Filtration
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发布时间：2022-09-18 - 摘要：In recent years, some scholars have found that there exists the relaxation time for the electrospinning jets during electrospinning, and the forming reasons have been partially explained. The impact on the resultant nanofiber morphology from the relaxation time of the electrospinning jets has not been investigated. As a matter of fact, the relaxation time of the electrospinning jets is linked to the charged nature of the spinning solution; meanwhile the electrospun fiber morphology could be closely related to the charged nature of the spinning solution, indicating that there are important connections between the relaxation time of electrospinning jets and the charged nature of the spinning solution. In this study, 20% w/w PVA solution was used to conduct electrospinning experiments on the needle electrospinning equipment based on three different electric field setups, and the spinning jets were recorded with a high-speed video camera. Furthermore, the electrospinning mechanisms of these setups and the relationships between the electrospun nanofiber morphology and the relaxation time of the electrospinning jets were analyzed systematically, in combination with the electrospun fiber morphological features. The results indicated that the reason for the intermittency of the electrospinning jets was due to the existence of the relaxation time of the electrospinning jets, which could be directly linked to the accumulation speed of the ionic charges on the surface of the Taylor cone, and the latter could be attributed to many factors, such as the ambient atmosphere of the position of the spinning solution, the viscosity of the solution, the ionic concentration of the solution, the electric field intensity and voltage of the position where the solution is located at, and so on. As a result, the ununiformity of the electrospun fibers and the change in the surface morphology of the nanofiber materials could be attributed to the presence of the relaxation time of the electrospinning time.关键词：Relaxation time of electrospinning jet;Ionic charge;Double electric layer;Reverse electric field;Critical voltage
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发布时间：2022-09-18 - 摘要：In this study, the crystallization behaviors of polylactide (PLA) and its composites with different nucleating agents were investigated by differentical scanning calorimtery (DSC), polarizing optical microscope (POM) and X-ray diffraction (XRD). Four different types of nucleating agents, including inorganic fillers (LAK and talc) and poly(D-lactide)(PDLA3.4 and PDLA6), can effectively enhance the crystallization behavior of PLA. Furthermore, LAK was confirmed to be the most effective one, which significantly accelerated crystallization rate and increased the crystallinity. With the addition of 5wt% LAK into PLA, the half crystallization time (t1/2) can be decreased into two minutes and the crystallinity was increased to be 33%. Based on the Avrami’s equation, the inorganic fillers have no influence on the nucleation mechanism and geometry of crystal growth of PLA. However, with the addition of PDLA into the PLA matrix, the enhanced crystallization can be explained by the formation of PLA stereocomplex (PLA-SC), which was found to have a much higher melting temperature and then acted as heterogeneous nucleating agents. XRD results indicated that the addition of nucleating agents had no influence on the crystalline structure, while the addition of PDLA significantly changed the crystal morphology according to the POM investigation.关键词：PLA;Nucleating agents;Crystallization behavior
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发布时间：2022-09-18 - 摘要：The tri(4-hydroxyphenyl)methane was synthesized by using phenol and p-hydroxy benzaldehyde as feed stock, p-toluenesulfonic acid and aluminium chloride as catalyst. The chemical structure of tri(4-hydroxyphenyl)methane was characterized by Fourier-transform infrared (FTIR) spectrometer and 1H NMR spectrometer. Four factors such as usage of catalyst, reaction temperature, material ratio and reaction time was studied in experiment, with the increasing of the reaction temperature, the yield increased; with the increasing of catalyst usage, the yield showed an earlier raised and later decreased; with the increasing of material ratio, the yield increased, and then trends toward constance. The result shows that the optional process is that n(phenol)/n(p-hydroxy benzaldehyde)is 10:1, n(p-toluenesulfonic acid)/n(p-hydroxy benzaldehyde) is 1:2, n(aluminium chloride)/n(p-hydroxy benzaldehyde) is 1:6, reaction time is 4h and reaction temperature is 45℃. Under the processing parameter, the yield of product is up to 90%, the purity of the product is up to 99%.关键词：Tri(4-hydroxyphenyl)methane;Synthesis processing;p-Hydroxy benzaldehyde;Phenol;Epoxy resin
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发布时间：2022-09-18 - 摘要：Nano-TiO2 catalytic materials based on amidoxime fiber were prepared by coordination-hydrolysis method in room temperature. The morphology, crystal structure and surface composition were determined by SEM, XRD and EDS.The experiment results showed that TiO2 were amorphous, nano-particles exist on the surface of AOCF. The results of photodegrading methylene blue, methyl orange and reactive red which concentration was 50mL 25mg/L showed the rate of photodegradation was 100% in 90min with 1.000g catalyst; The catalyst can be reused for 7 times while the degradation rate was still above 80%.Catalytic degradation reactions of the three kinds of solution are first-level dynamics. Nano-TiO2/AOCF is a new and efficient photocatalyst owing to its good catalytic activity in degradation of dye solution.关键词：AOCFs;Nano-TiO2;Photo catalytic
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发布时间：2022-09-18 - 摘要：Change of electromagnetic field has a great influence on conductivity and congulation performance of PFS dissolved liquid. It can be turned by alternating electromagnetic: under normal condition, the conductivity value of PFS dissolved liquid treated by alternating electromagnetic increased 14%, stability improved double, effluent turbidity improvrd double, dosage saved 2 times; Clear positive correlation was shown between them, Between the conductivity and hydrolysis performance exist clear positive correlation. Both of them displayed V shape in voltage range of 0~220v, current range of 0~1.2A, frequency range of 0~200, 200~400Hz, magnetizingtime range of 0~180s, Voltage, current, high frequency, band frequency and magnetization time change, electric charge neutralization of PFS is a leading ability, at low-band frequency,adsorption and bridging is a leading ability,the best parameters for voltage is 100v, current is 0.7A, frequency is 150Hz, magnetizingtime is 60s.关键词：Electromagnetic field;PFS;Conductivity;Coagulation performance;Stability
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发布时间：2022-09-18 - 摘要：Polyaniline(PAN) film, Poly 2,5-dimethoxyaniline(PDMA), film and Poly(aniline,2,5-dimethoxyaniline) (PAN/PDMA) composite film with high adhesion strength, uniform and excellent cyclic voltammetry were synthesized by cyclic voltammetry on ITO glass. The effect of scan rate on the shape and cyclic voltampere characteristics of PAN film, PDMA film and PAN/PDMA composite film were discussed. The chemical structure and AC impendence was characterized respectively by FTIR, UV-Vis and EIS. The results showed that the optimum scan rate of PAN film, PDMA film and PAN/PDMA composite film were 10mV/s, 10mV/s and 100mV/s, respectively. The adhesion, surface uniformity, density degree, cyclic reversibility and electrode capacitance of the composite film are better than that of the two films. PAN and PDMA homopolymerization chains were bonded by chemical bonds and the conjugated degree of macromolecular chains in PAN/PDMA composite film was apparently higher than that of pure PAN chain when aniline and 2,5-dimethoxyaniline copolyed. The AC impendence of PAN/PDMA composite film was lower than that of the two films.关键词：Cyclic voltammetry;Polyaniline;2, 5-Dimethoxyaniline;Composite film
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发布时间：2022-09-18 - 摘要：The polysilcoxane containing p-silphenylene was synthesized through ring-opening polymerization and dehydration condensation. The Effect of proportion of raw materials, amount of catalyst and temperature on the yield of reaction and the content of phenylene on the thermal performance of siloxane were systematically studied in this article. And the structure of the polymer was characterized by fourier transform infrared spectroscopy(FT-IR) and hydrogen nuclear magnetic resonance(1H NMR). Molecular weight characteristics and thermal stability of the silicone were characterized by gel permeation chromatography(GPC) and thermal gravimetric analysis(TGA), respectively. The results show that polysilicone containing p-silphenylene unit has been successfully prepared with this method and its molecular weight is controllable and greater than theoetical value and polydispersity index is 1.33 to 1.45. The yield is reduced with the increase of BHB in precursors, whereas it is improved with the increase of catalyst and reaction temperature. The 10% weight loss temperature was increased from 352℃ to 477℃ in air when p-silphenylene unit content is 15.09% and p-silphenylene unit significantly improved polysilicone thermal stability at high temperature.关键词：Polysiloxane;p-Siphenylene;Ring-opening polymerization;Dehydration condensation;Thermal oxidation stability
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发布时间：2022-09-18 - 摘要：During the deformation process of polymer materials, environmental temperature can take a great effect on mechanical properties, but heat caused from material itself can not be ignored. When the tests were performed on thicker samples with sufficiently fast extension rates, namely in approximate adiabatic conditions, the information of materials including molecular structure and deformation mechanism can be acquired by the feature of thermal effects. In this paper, several thermal effects of polymer materials including small elastic, plastic, large elastic deformation and fatigue are reviewed, characterization technique of thermal effects involved in deformation calorimetry, thermocouple, infrared thermography.are presented.关键词：Polymer materials;Thermal effects;Characterization technique;Infrared thermography
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发布时间：2022-09-18 - 摘要：Polyamidoamine, composed of centre core and highly symmetrical dense outer layer, is dendritically shaped molecule with quantities of functional groups, the amount of which increases geometrically with the generation growth. The unique structures determine particular performances. Consequently, it has been widely applied in environmental contamination treatment. The paper refers to the structures, the synthesis of PAMAM, as well as reviews of their up-to-date research on the application of polluted water treatment. It is proposed that they have a better application prospects in water treatment aspect, and the future research direction on this very aspect is put forward.关键词：Polyamidoamine;Organic contamination;Heavy metals;Oily wastewater
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发布时间：2022-09-18 - 摘要：Owing to resources shortage has become a global problem, papermaking industry becomes more and more restricted by factors such as raw materials, environmental protection and fund, recycling waste paper pulp has become one of the important ways to resolve the shortage of papermaking raw materials. Recycling waste paper pulp is a great invent to increase economic income, protect the ecological environment, reduce pollution event in the civil dispute. In this paper, the importance of comprehensive utilization for pulp sediments, pulp sediment performances, performance and pulp sediments composites research status in domestic and foreign, were introduced. It was elaborated to pulp sediment as a composite material base phase, preparation of used rubber powder/pulp sediment composite materials and research results of used rubber powder/pulp sediment composites materials. Finally, the development trend of pulp sediment composites was previewed.关键词：Pulp sediments;Composites;Research status;Development
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发布时间：2022-09-18 - 摘要：In this paper, we introduced a new opened comprehensive experiment about polymer hydrogel.To improve students’ scientific research ability, six different experiments connected with each other about polymer hydrogel were designed combining with fiber materials, hydrogel and organic/inorganic hybrid materials. Experiments were rich and colorful as well as simple and easy to operate. Students are free to select the different experiments, design experimental procedure and operate. In this way the lack of "autonomy"and "design" in the comprehensive experiment was solved and giving fully the students’own initiative. Experimental results showed that the experimental design was reasonable and can fully stimulate the students’ interest and enthusiasm as well as effectively cultivate college students’abilities of discovery, understanding and solve problems independently. It is worthy of further promotion.关键词：Comprehensive experiment;Polymer hydrogel;Experimental teaching reform;Research capability;Teaching impact evaluation
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发布时间：2022-09-18 - 摘要：The inquiry teaching was applied in the three sections of the chapter "Polymer Molecular Motion and Transition" for "Polymer Physics" course. First of all, based on the students’ability, the appropriate teaching model was selected and the inquiry activities were designed. Then, the theory research and experimental research were completed under the guidance of the teachers. The results showed that the inquiry teaching has greatly improved the students’ learning interest, the independent thinking and the practical ability. But, there are some difficulties in the course of inquiry teaching, inquiry teaching is time-consuming, some students can not adapt this teaching model and it is not easy to find the interesting situational questions. The inquiry teaching method needs to be improved in the following teaching process.关键词：Polymer physics;Inquiry teaching model;Teaching method;Teaching effect
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发布时间：2022-09-18 - 摘要：Polymer chemistry is a professional basic course for students majored in polymer, and to master the first class is important to the study of subsequent courses. For improving the teaching effect, it is extremely important to give an excellent first class. During the first class, this paper discussed how to give an excellent first class from that learning polymer chemistry is interesting and useful, what to learn, as well as setting the targeted homework. Based on the zero contact with this course for the students, to make them interested in learning, clear what to learn, what to focus on and put their learning to use. Thus, the overlapping and mutual penetration of "teaching, learning and using" can be attained in the teaching process, and especially to lay a good foundation for the teaching of subsequent course of polymer chemistry.关键词：Polymer chemistry;First class;Teaching method
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发布时间：2022-09-18 - 摘要：Designed a comprehensive teaching experiment, students were panel discuss about the selection and preparation of the sample, and drew up the experimental scheme. In the experimental teaching, we guided students to use GC-MS to detect the sample PAEs, antioxidants, flame retardants. Through the experiment, the students had intuitive understanding of polymer additives that easy to migrate to the natural environment, and their scientific research quality was initially increased. The experimental was easy to operate, successfully applied to teaching of specialized subjects, and the effect was good.关键词：Environmental samples;Polymer additives;Teaching experiment;Extraction
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发布时间：2022-09-18
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