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Thermal ageing of soft and hard epoxy resins

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High Voltage 2023年第1期8卷 12-20页

作者： Yoshimichi Ohki Naoshi Hirai Research Institute for Materials Science and Technology Waseda UniversityShinjuku-kuTokyoJapan

Two kinds of epoxy resin,a soft one with rubber-based additives and an ordinary hard one,are used as electrical insulators and airtight sealants in electrical penetrations in nuclear power plants(NPPs).Knowing how they behave under adverse environments is important for the safe operation of *** this regard,we gave artificial thermal ageing treatment to the two resins by heating them in air at various *** resins were then subjected to mechanical,thermal,and dielectric *** a result,it has become clear that the soft epoxy resin becomes hard,while its permittivity and loss factor decrease as the heating becomes *** glass transition tends to occur at a high temperature in the soft epoxy resin when it was *** these changes,the soft resin tends to exhibit similar behaviour in various properties to that of the unaged hard *** the other hand,the hard one is hardly affected by the simulated thermal ***,both resins can be useable in NPPs.

关键词： resin resins heated

Hydrolysis Activities of resins of Complexes Made from Polysaccharides and Ce^(4+)

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Journal of Rare Earths 2006年第z2期24卷 125-129页

作者：于丽娜汪东风李海燕苏琳王家林 College of Food Science and Technology Ocean University of China Tsingtao Brewery Company Limited

resins of complexes made from agarose-Ce4+ (RCA-Ce) and chitosan-Ce4+ (RCC-Ce) were prepared. Hydrolysis rates of methamidophos, omethoate and chlorpyrifos treated by RCA-Ce were 32.39%, 27. 12% and 46.62%, respectively, those of chlorpyrifos and methamidophos in mung bean sprout juice 38.28% and 35.45% , and that of chlorpyrifos in tea extract 59.76% . Hydrolysis rates of protein in tea extract treated by RCA-Ce increased by 86.46% . RCC-Ce could be employed in the apple juice production. The contents of methamidophos and parathion-methyl in the juice treated by RCC-Ce decreased 58.76% and 71.92% . Furthermore, RCC-Ce was used to clarification for beer by the ways of a column. RCC-Ce could hydrolyze sensitive protein and increase contents of free amino acid in the beer. Therefore, the beer treated by RCC-Ce could stay oxidation and aging procedure due to some metal ions being absorbed by RCC-Ce.

关键词： resins polysaccharides cerium hydrolyze protein organophosphorous pesticides rare earths

Dielectric behaviours of bio-derived epoxy resins from cashew nutshell liquid

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High Voltage 2021年第2期6卷 255-263页

作者： Mulan Mu Alun Vaughan Department of Electronics and Computer Science Tony Davies High Voltage LaboratoryUniversity of SouthamptonSouthamptonUK Novel Polymer Technology Section TWI LtdCambridgeUK

In this study,four commercially available bio-derived epoxy systems(extracted from cashew nutshell liquid)were prepared and *** glass transition temperature(Tg),dielectric spectroscopy,DC conductivity and breakdown properties of these epoxy resins were *** scanning calorimetry(DSC)demonstrated that the T_(g) of the investigated systems ranged from 67 to 122°*** DC conductivity was very low(<10^(-16) S cm^(-1))and comparable to the conventional dielectrics at room temperature(RT).However,all systems showed a strong temperature dependence of the electrical conductivity and exhibited sharp increase around their respective T_(g).Arrhenius analysis led to activation energy,E_(a),values around 1 eV;higher E_(a) values were observed in systems with a lower T_(g).Dielectric spectroscopy revealed a flat and low response at temperature below T_(g).However,both the real and imaginary permittivity increased with decreasing frequency at mid to low frequencies as the temperatures approached T_(g).The variations of AC breakdown strength of all samples were not statistically significant,but the DC breakdown strength of sample 2503Aþ2002B was higher than the others,which might be due to reduced charge transport in this *** results indicate that novel bio-derived epoxy systems from renewable sources are potential alternatives for traditional petroleum-based epoxy systems in certain insulation applications.

关键词： conductivity resins liquid

Epoxy thermoset resins with high pristine thermal conductivity

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High Voltage 2017年第3期2卷 139-146页

作者： Ying Lin Xingyi Huang Jin Chen Pingkai Jiang Shanghai Key Laboratory of Electrical Insulation and Thermal Ageing Shanghai Jiao Tong UniversityShanghai 200240People's Republic of China

Heat dissipation becomes a critical problem because of the miniaturisation and the increase of power density in electronic devices and electric equipment,which calls for electrical insulating materials with high thermal management *** thermosets have been widely used as electrical insulating materials,but suffer from their low thermal *** study reviewed the research progress on the development of epoxy thermosets with high pristine thermal ***,the thermal conduction mechanism of polymers was briefly ***,the approaches used to enhance the thermal conductivity of epoxy thermosets were summarised,which mainly dealt with the formation of microscopically anisotropic but macroscopically isotropic structure in the epoxy ***,the applications of high thermal conductivity epoxy thermoset resins were ***,the review provided the existing challenges and the future directions for the development of epoxy thermosets with high pristine thermal conductivity.

关键词： thermal conductivity resins

Rheological behavior of novel polyamide 6/silica nanocomposites containing epoxy resins

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Journal of Central South University 2008年第S1期15卷 76-79页

作者：赵才贤张平陈广兵王霞瑜 Institute of Fundamental Mechanics and Material Engineering Xiangtan University Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education Xiangtan University

A novel polyamide 6/silica nanocomposite containing epoxy resins(EPA6N) was prepared via in situ polymerization using tetraethoxysilane(TEOS) as the precursor of *** dynamic rheological properties of pure PA6 and EPA6N at temperatures of 225 and 235 ℃ were *** results of transmission electron microscopy(TEM) and atomic force microscopy(AFM) indicate that the silica particles are well dispersed in the polyamide 6 matrix on about 30 nm in diameter,which demonstrates that this method can effectively avoid agglomeration of the inorganic *** rheological results suggest that pure PA6 shows Newtonian ***,the novel EPA6N exhibits a solid-like rheological behavior,which is due to the small size,large surface of silica particles and the stronger polyamide 6-silica chemical bond formed through the reactions of epoxy resins with end groups of PA6 molecular *** EPA6N also exhibits higher melt viscosity,storage modulus and loss modulus than those of pure PA6.

关键词： polyamide 6 nanocomposites epoxy resins rheological behavior viscosity

Monosized macroporous resins with epoxy groups and their structure and gel chromatography properties

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Chinese Science Bulletin 2000年第3期45卷 220-223页

作者： Chao Jin Yanguo Yang Zhongzhang Zhao Shuming Yang Xiulan Tian Tiansheng Su Chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

The monosized macroporous-polymer beads based on cross-linked poly(glycidylmethacrylate) have been synthesized by a new improving method-combining dispersionpolymerization with swelling polymerization and polymeric solution porogens. The structure and gel chromatographic properties of the resins have been studied. The resins as matrix materials of various types of high performance liquid chromatography (HPLC) packings possess excellent separation

关键词： : cross-linked poly(glycidyl methacrylate) beads monosized macroporous resins HPLC packings.

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Science China Chemistry 2010年第9期53卷 1844-1852页

作者： WANG Zheng1,YANG RuLei1,ZHU JunDong & ZHU XiaoXia2 1School of Pharmaceutical Science and Technology,Tianjin University,Tianjin 300072,China 2Département de chimie,Université de Montréal,Montréal,QC H3C 3J7,Canada 1. School of Pharmaceutical Science and Technology Tianjin University Tianjin 300072 China2. Département de chimie Université de Montréal Montréal QC H3C 3J7 Canada

Combinatorial chemistry has become a significant part of the discovery and optimization process for novel drugs,affinity ligands,and *** polymeric supports play a key role in combinatory ***,various kinds of functional polymer resins have been exploited as supports,reagents,and catalysts in organic *** comparison to the conventional Merrifield resins,the poly(ethylene glycol)(PEG)-related polymer resins have advantages including good compatibilities with polar solvents,good solvent absorbency and swelling *** review focuses primarily on the more recent work in the field of developing PEG-related polymer resins as supports for organic synthesis.

关键词： combinatorial chemistry polymer resins poly(ethylene glycol) organic synthesis

SYNTHESES AND PROPERTIES OF 3-METHOXY-DIPHENYLAMINE-4-DIAZONIUM SALTS AND THEIR DIAZO resins

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Chinese Science Bulletin 1989年第20期34卷 1709-1712页

作者：曹建伟曹维孝冯新德 Department of Chemistry Peking University

This note reports for the first time the preliminary results concerning the syntheses of 3-methoxy-dephenylamine-4-diazonium salts (M DADS)and the structures and properties of diazo resins produced by them and 4,4′-d... 详细信息

关键词： diazo resins photosensitivity thermostability nucleophilic substitution light sensitive printing plate

China's C5 Petroleum resins Makers Need to Enter High-End Markets

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China Chemical Reporter 2010年第22期21卷 29-30页

作者： Yu Chunmei,Zhang Hui,the Jilin Design Institute of PetroChina Northeast China Refining & Chemical Engineering Co Ltd

The comprehensive utilization of C5 cutfraction and its derivatives is becoming ahighlight in the petrochemical industryworldwide. Among them,C5 petroleumresins have already become a product serieswith the highest output,the greatestvariety and the fastest development in thecomprehensive utilization of cracked C5cut fraction in the world,with the reportedaverage annual growth of around 5% in recentyears. The global total capacity ofpetroleum resins was around 570 000 t/ain 2008 and the output was 500 000 tonswith hydrogenated petroleum resins accountingfor 5%.China started the development。

关键词： Petroleum resins petrochemical petroleum Shandong