最新刊期
卷 25 ， 期 7 ， 2012
- 摘要：This paper reviewed the achievements in catalyst preparation, polymerization technology design, structure-property correlation and practical application of PP in-reactor alloys.The basic PP in-reactor alloys ranging from high rigidity to high toughness were successfully produced in the pilot experimental device for PP, which was catalyzed by the modified Ziegler-Natta catalyst with the addition of novel sulfonyl electron donor or Ziegler-Natta/metallocene complex catalyst.A series of automobile-used PP special materials, obtained by blending the basic resins with additives or natural fibers, were used to prepare typical automobile components.The molding technology and practical application of the automobile components were systematically investigated.关键词：PP in-reactor alloys;Singleness;Preparation of catalyst;Pilot experimental device;Molding and application
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发布时间：2022-09-18 - 摘要：The study of macromolecular chains condensation will be beneficial with the discussion about polymer solutions.The transitions from dilute solution to semi-dilute and to concentrated solution were in nature the process of interlace, entanglement and condensation of a lot of isolated single chains.This can be known as lyotropic condensation.The types of chains lyotropic condensation are varied, e.g.condensed to amorphous state, to crystal state, and sol-gel transition etc.The characters of these processes were discussed.The basic physical problems in lyotropic condensation: e.g.many-body effects, correlations, mean field approximation, critical index and the new study method——scaling laws were brief introduced.关键词：Macromolecular chain;Condensed state;Lyotropic condensation
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发布时间：2022-09-18 - 摘要：Interventional therapy is the new treatment between surgical and medical treatment, and the non-vascular interventional treatment includes bile duct, esophagus, trachea and other bureaucratic.Non-vascular biodegradable stents have great biocompatible with bureaucratic, and they will degrade into harmless small molecules out of the body during a certain time after stents are replanted in body.In this paper, the research progress of non-vascular biodegradable stents were reviewed, and material selection, shape design, stent process (including stent molding, film modification and drug treatment), Performance tests (including physical properties, mechanical properties, biocompatibility, degradation properties, etc.) and progress in clinical application of non-vascular biodegradable stents were mainly introduced.关键词：Stents;Biodegradable;Non-vascular;Biodegradable polymer;Bureaucratic
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发布时间：2022-09-18 - 摘要：Compared with liquid electrolyte, polymer electrolyte has widely attracted researchers’ attention, and has the potential to replace organic liquid electrolyte because of the advantages such as easy processing, flexible design, light weight, safety and non-toxicity.Hyperbranched/star polymer with amorphousness, low glass transition temperature and unique topology has been studied as solid polymer electrolyte.In this review, research progress in hyperbranched/star polymer electrolyte is presented.Special interests are focused on the hyperbranched/star polymer-based electrolytes, hyperbranched/star polymer blend-based electrolyte.Besides, the application of hyperbranched/star polymer-based single ion electrolyte for lithium ion battery is also prospected.关键词：Polymer electrolyte;Hyperbranched polymer;Star polymer;lithium ion battery
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发布时间：2022-09-18 - 摘要：Herein, the conventional preparation methods of cationic polymer microsphere, highlighting the progress of (emulsifier-free) emulsion polymerization, dispersion polymerization, microemulsion polymerization, as well as the application in profile conformation, electrorheology fluid, biomedicine, are reviewed, and origin of cationic charges in the microsphere surface and cationic monomers used in world-wide published works are systematically summed up. Moreover, the specifications of various processes for preparation are elucidated. Recently, a number of new methods like clicking chemistry, atom transfer radical polymerization for this use have paved a way for the control of surface property of microsphere. Thus, the outline on the future directions and challenges come with the design and engineering of cationic polymer particles is concluded.关键词：Cationic polymer microsphere;Emulsion polymerization;Dispersion polymerization;Microemulsion polymerization;Grafting modification
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发布时间：2022-09-18 - 摘要：The resin with oxazolidone structure exhibits excellent heat resistance, electrical insulation, physical and mechanical properties and so on.Add oxazolidone ring to epoxy,the glass transition temperatures,the adhesive force,the dielectrical property and the flame retardant of cured products were improved.The research progresses on general synthesis method of oxazolidone epoxy resin,explores influence on synthesis reaction of oxazolidone epoxy resin including ratio of raw materials,reaction temperature,catalyst type and dosage,analyse the connection between curing agent and the property of cured products,In a process for producing application in kinds of fields of oxazolidone epoxy resin in details, including insulation, paint, bond, print circuit board, resin matrix and the like,and take a outlook of oxazolidone epoxy resin.关键词：Oxazolidone;Epoxy;Progress
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发布时间：2022-09-18 - 摘要：The advantages and shortcomings of all kinds of non-halogen flame retardants for preparing microcapsule core materials were introduced, such as inorganic flame retardant, intumescent flame retardant, nitrogen and phosphorus flame retardant. Based on the shell materials of microcapsule flame retardants, summarized the lastest research progress of flame retardant’s inorganic covering, organic resin covering, double-layers or multi-layers covering and synthesis flame retardants for covering. In the last section, four preparation methods for microcapsule flame retardants were represented, i.e., interfacial polymerization, in-situ polymerization, sol-gel method and supercritical methods, and the coming research fields of microcapsule flame retardant were prospected.关键词：Flame retardant;Microcapsule;Polymer
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发布时间：2022-09-18 - 摘要：The auxiliaries is an important part of emulsified asphalt used in CA mortar,It’s widely used with the rapid development of high speed railway.In this paper the important action of auxiliaries to emulsified asphalt used in CA mortar and CA mortar are expounded.The varieties of auxiliaries for CA mortar with emulsified asphalt are reviewed, the impact of auxiliaries on the emulsified asphalt used in CA mortar and CA mortar and its function mechanism are discussed in detail. Furthermore, the select and coordination function to auxiliaries are introduced,and the application example was also introduced.Additionally,the current situation and future development of auxiliaries are also presented.关键词：CA mortar;Emulsion asphalt;Auxiliaries;Stabilization;Rheological behavior
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发布时间：2022-09-18 - 摘要：Compared with conventional hydroxyl-terminated polyethers, the fluorine-containing polyether polyols can be used to prepare polymers with better performances, such as water repellent and oil repellent, self-cleaning, self-lubricating, and resistant to heat, UV light, weathering, corrosion, chemical, solvent and so on. Therefore it has a wide range of potential applications and development prospects. In this article, preparation technical approaches and chemical structure features of fluorine-containing polyether polyols at home and abroad have been reviewed in detail. Research progresses on fluorine-containing polyether polyol used in polyurethane elastmers, coatings and other application areas are briefly introduced. It is pointed out that the main directions of fluorine-containing polyether polyols for the future research and development should focus on lowering products costs, developing green high performance technical process, simplifying preparation techniques, optimizing the process conditions, and developing new products.关键词：Fluorinated polyurethane;Fluorine-containing polyether polyol;Synthetic methods;Technical process
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发布时间：2022-09-18 - 摘要：Six new chiral (meth)acryalte liquid crystalline monomers (M1~M6) derived from menthol were synthesized. The corresponding polymers (M1~M6) were obtained by means of free radical polymerization of these monomers with azobisisobutyronitrile (AIBN) as an initiator and toluene as a solvent. The chemical structures of the obtained intermediate, monomers and polymers were characterized by FT-IR, or 1H NMR. The average molecular weight was determined by gel permeation chromatography (GPC). The specific optical rotations were evaluated with a polarimeter. The experimental results showed that the specific optical rotations of M1~M6 and M1~M6 were all left-handed, which indicates that the configuration or rotation direction of these chiral new compounds is hardly affected by a series of chemical reaction. In addition, the specific optical rotation values decreased with increasing the number of phenyl ring or the length of flexible spacer. However, the specific optical rotation absolute values of M1~M6 were less than those of the corresponding monomers.关键词：Menthol;(Meth)acrylate;Monomer;Polymer;Synthesis
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发布时间：2022-09-18 - 摘要：The 2,6-Bis(imino) - Pyridyl Ligands iron-based catalysts supported on SiO2 were prepared. The catalytic activity and selectivity of the system in ethylene oligomerization were studied under different supported temperature, reaction pressures, the amount of catalysts and propylene.The results showed that low supported temperature is good to catalytic activities. The activity cycle increased and polymerization temperature was stable, and ethylene conversion of unit cocatalyst methylaluminoxane(MAO) increased when using section pressure mode. But the selectivities of α-olefins almost invariant. The activities calculated by unit MAO increased after SiO2-supported. With the increase of catalysts, the ethylene conversion of unit MAO increases. The activities decrease when adding propylene and more low-molecular-weight products were produced.关键词：α-Olefins;Ethylene oligomerization;SiO2-supported iron-based catalysts
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发布时间：2022-09-18 - 摘要：Solution crystallization of polyoxymethylene(POM)/poly(ethylene oxide)(PEO) (50/50) blend with different molecular weight(
of PEO, using hexafluoroisopropanol (HFIP) as common solvent, was studied by differential scanning calorimeter(DSC), scanning electron spectroscopy(SEM) and infrared spectra (IR).It indicated that the lower of PEO, the stronger interruption between POM and PEO in the crystallization. When of PEO was 4×103,POM formed partial imperfect crystals, thus showing obvious double melting peaks in the blend. SEM results showed that no obvious phase separation occurred in the POM/PEO blend with different of PEO and it was easier for the blend with lower of PEO to form regular spherulites. It was expected that the interpenetrated structure was formed in the POM/PEO 50/50 blend through solution crystallization. 关键词：Polyoxymethylene;Poly(ethylene oxide);Solution crystallization- 2
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发布时间：2022-09-18 - 摘要：Sueprabsorbents poly(acrylic acid/acrylamide) (PAAM) are prepared from partly neutralized acrylic acid(AA) and acrylamide(AM) by inverse suspension copolymerization. The influence of some main factors on its absorbency such as mol ration and neutralization of the monomers, the mass concentrations of the crosslinker,the initiator, and the initial temperature and the reaction time is discussed in detail. And then the structure and thermal property of PAAM are tested by FTIR and TGA. The optimum formula is obtained as follow:the mass concentration of all monomers (w) is 30%, the neutralized degree (N) is 75%, mol ratio of acrylic acid(AA) and acrylamide(AM) is 7:3, the mass concentrations of the crosslinker(NMBA), the initiator(KPS) and the dispersing agent relative to all total monomers mass are 0.065%, 0.7% and 0.5%, respectively, the drop-additive rate of the monomers solution is 2-3ml/min, the polymerizarion temperature and time are 70℃and 1.5h. The maximum absorbencies of PAAM in distilled water and in 0.9%NaCl solution under the optimum formula are 1300g/g and 93g/g. The thermal stability of PAAM before 320℃ is good.关键词：Superabsorbent;High water-absorbing resin;Acrylic acid;Acrylamide;Absorbency;Poly(acrylic acid-acrylamide)
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发布时间：2022-09-18 - 摘要：We measure the crystalline temperature and melt temperature of PCL by DSC.then, the effect of crystallization time was studied by Polarized Optical Microscope (POM),we find that:the change of crystallization time only change dimension of crystal, it did not influence the crystalline morphology. At last, Crystalline morphology of Poly(ε-caprolactone) was studied by AFM. At this paper,we mainly discussed the effect of substrate material、solvent and super cooling on crystalline morphology. It was found that:(1) the effect of substrate material on crystalline morphology is prominence,crystalline morphology on the silicon present club-structure, while on mica and on mica coated Carbon film on surface is dendrite structure.(2) the effect of solvent on crystalline morphology is prominence, it mainly depended on the vapor pressure. (3) the dendrites structure could be found at different temperatures, the width of dendrites increase with decreasing super cooling.关键词：Poly(ε-caprolactone);Crystallization;Banded spherulite;Crystalline morphology
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发布时间：2022-09-18 - 摘要：Medical balloon has been widely used for the treatment of cardiovascular and cerebrovascular diseases, but the theoretical studies in processing process of medical balloon have reported less in the domestic. This paper introduced briefly in the processing process of medical balloon at first, and producted a series of balloon with the nylon 12 as raw materials, through first molding, second forming and final molding process of the operating conditions of control. Then the compliance change in the molding process were studied with hydraulic blasting apparatus, And the internal structure, material’s melting point, crystallinity and the change of the interior Chemical groups of the nylon 12 during the molding process were separately inspected, using X ray diffraction (XRD), Differential Scanning Caborimetry (DSC) and infrared transmission spectroscopy experiments. The acting force between the polymeric chain of nylon 12 reduced at the first, so that the material has better plasticity and machinability, and then the acting force of polymer chain is enhanced, so that the final balloon has higher strength and stability were discovered through the characterization in three of the above processing steps.关键词：Medical balloon;Nylon 12;State of aggregation changes
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发布时间：2022-09-18 - 摘要：Composite resin of Epoxy-Acrylic was prepared by free radical-cationic hybrid curing systemin visible light-cured, and the influence of the proportion of free radical (CQ) and cationic initiator (DPI·PF6) on curing time, curing depth, linear dimension change and properties of composition were mainly studied. The results show: when the mass fraction of CQ is 0.75, the curing time is 6s, the curing depth is 7.86mm, the linear dimension change is 0.2%, and the synthetic performance of the composite resin is excellent. This result demonstrated that free radical-cationic hybrid curing system combined the advantages of radical and cationic polymerization, and exhibited a better synergy effect.关键词：Free radical-cationic hybrid curing system;Visible light;Curing property;Synergy effect
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发布时间：2022-09-18 - 摘要：As polymer science has widely penetrated into other subjects, polymer physics course is open to students majoring in applied chemistry of Tianjin University as a professional basic course. Compared to polymer majors, polymer physics course open to applied chemistry major has shortages of fewer teaching hours and no corresponding experiments. This article introduced some measures about polymer physics teaching in applied chemistry major, such as selection of teaching content based on professional characteristics, weakening some secondary contents and derivation of formulas, combinations of demonstration experiments, object teaching, multimedia teaching with problem driving teaching, introduction of the polymer physics history and humanistic spirit in classroom teaching.关键词：Polymer physics;Teaching experience;Application chemistry major
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发布时间：2022-09-18 - 摘要：Auto-acceleration effect is one of the important characteristics of radical polymerization macrokinetics, which have great influence on polymerization progress and the synthesized product. The content of auto-acceleration effect is an emphasis and difficulty in the teaching and learning of radical polymerization kinetics. In order to help students understand the related content of auto-acceleration, the experimental phenomena, cause, results generated and influencing factors of auto-acceleration as well as the difference between auto-acceleration effect and the gelation of three dimensional polycondensation were summarized in this paper with reference to relevant polymer chemistry textbooks.关键词：Polymer chemistry;Radical polymerization;Auto-acceleration effect
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发布时间：2022-09-18
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