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Study on effect of crosslink structure on decomposition of epoxy resins in nitric acid

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Journal of Harbin Institute of Technology(New Series) 2012年第4期19卷 19-25页

作者：刘宇艳李犁吴松全唐宇攀 School of Chemical Engineering and Technology Harbin Institute of Technology Dept.of Materials Science and Engineering Carnegie Mellon University

One chemical approach using nitric acid as the solvent to decompose thermosetting epoxy resin was discussed. The samples were prepared by using different kinds of curing agents, namely polyamide (PA651), isophorone diamine (IPDA), 4,4'-diaminodiphenylmethane (DDM) and 2-ethyl-4-methy-imidazole (EMI-2,4) and different kinds of epoxy resins, namely bisphenol-A epoxy resin(E-44), bisphenol-A epoxy resin(E-51), N,N,N',N' teraglycidy 4,4' diaminodiphenyl methane (AG-80) and diglycidyl-4,5-epoxycyclohexane-1,2-dicarboxylate (TDE-85). Their effects on decomposition rate were investigated and the decomposition products were analyzed by Infra-red (IR) spectra, and Gas Chromatography-Mass Spectrometry (GC-MS). Based on conclusions drawn from experiments, the mechanism of degrading thermosetting epoxy resin with nitric acid was envisaged tentatively.

关键词： epoxy resin nitric acid chemical decomposition

CTBN-TOUGHENED epoxy resinS——EFFECT OF CURING MECHANISM ON NETWORK STRUCTURE OF THE RUBBER PHASE

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Chinese Journal of Polymer Science 1990年第2期8卷 183-187页

作者：宋爱腾余云照 Institute of Chemistry Academia Sinica Beijing

epoxy resins toughened with carboxyl-terminated butadieneacrylonitrile copolymers (CTBN) are two-phase thermosets. The network of the in situ formed rubber particles depends upon the curing mechanism of the resin. When a primary polyamine such as triethylene tetramine was used as curing agent, the network of the rubber phase was quite incomplete, whereas a perfect rubber network was formed with 2-ethyl-4-methyl imidazole as the curing agent.

关键词： epoxy resin toughening liquid rubber.

Statistical deduction and experimental verification on kinetic equations for the curing reactions of epoxy resins/amines

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Journal of Harbin Institute of Technology(New Series) 2005年第1期12卷 11-16页

作者：陈平吕祖舜余大书胡立江 Chemistry Center Harbin University of Commerce Harbin 150076 China Dept. of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Dept. of Physics Tianjin Normal University Tianjin 300074 China

Based on three typical mechanisms (second-order, third-order and competitive mechanisms) for the curing reactions of the epoxy resins with amines, a pair of the kinetic equations (for primary and secondary aminations) was presented to explain the uniformity and relationship among the three different kinetic mechanisms of the reactions. The presented macro-equations were deduced from the kinetic micro-equations by the statistics method. And the constitutive equations were verified by experimental data at different reaction times and temperatures (95°C, 60°C and 39°C), taking diglycidyl ether of bisphenol A (DGEBA) /ethyleneamine (EA) as a model.

关键词： epoxy resin amine unified kinetic equations curing reaction

Synthesis and Characterization of Modified epoxy resins by Silicic Acid Tetraethyl Ester and Nano-SiO_2

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Transactions of Tianjin University 2004年第2期10卷 105-108页

作者：李海燕张之圣 School of Electronic Information Engineering

A kind of modified epoxy resins was obtained by condensation of epoxy resin with silicic acid tetraethyl ester（TEOS） and nano-SiO2. The reactions were performed with hydrochloric acid as a catalyst at 63 ℃. The structure, thermal stability and morphological characteristics of the modified epoxy resins were studied through infrared spectra（FT-IR） analysis, thermogravimetric（TG） analysis and scanning electron microscopy respectively. It has been found from the IR and TG study that modified epoxy resins have greater thermal stability than epoxy resins, and its thermal stability has been improved by the formation of inter-crosslinked network structure. The modified epoxy resins exhibit heterogeneous morphology and heterogeneity increases with more TEOS feeding, which in turn confirms the formation of inter-crosslinked network structure in modified epoxy resins.

关键词： epoxy resin silicic acid tetraethyl ester(TEOS) nano-SiO_2 IR thermogravimetric analysis

Influence of aliphatic epoxy monomer on the blowing-out effect in the flame retardant epoxy resins

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Journal of Beijing Institute of Technology 2016年第3期25卷 418-428页

作者： ZHANG Wen-chao SONG Ting-lu YANG Rong-jie National Engineering Technology Research Center of Flame Retardant Materials School of Materials Science and Engineering Beijing Institute of Technology Beijing 100081 China

An aliphatic epoxy monomer＂polypropyleneglycol-diglycidylether（PPGDGE,YF878）＂is loaded in the epoxy resins（EP）to evaluate the influence of epoxy structure on the blowing-out effect,which is caused by 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide（DOPO）and octaphenyl silsesquioxane（OPS）.The flame retarding properties of these EP composites were tested using the LOI and UL-94 *** pyrolytic gases produced and the thermal stability of the EP composites with different flame retardants were detected by TGA-FTIR in *** negative effect of YF878 was detected from the TTI,HRR,and p-HRR results after the cone calorimeter *** char produced by the EP composites after the cone calorimeter test was investigated by *** is proposed that the aliphatic chain of the YF878 is easy to break down and produce combustible gases,so it does not easily form a crosslinked structure in the condensed *** results are very helpful for investigation of the conditions under which the blowing-out effect in epoxy resins can be caused by synergy of phosphorous and silicon.

关键词： epoxy resin silicon phosphorus flame retardancy blowing-out effect

Performance of steel bridge deck pavement structure with ultra high performance concrete based on resin bonding

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Frontiers of Structural and Civil Engineering 2021年第4期15卷 895-904页

作者： Hui ZHANG Zhixiang ZHANG Peiwei GAO Lei CUI Youqiang PAN Kuan LI Special Pavement Technology Center Jiangsu SinoRoad Engineering Research InstituteNanjing211805China College of Civil Avlation Nanjing University of Aeronautics and AstronauticsNanjing210016China

This research investigated a pavement system on steel bridge decks that use epoxy resin(EP)bonded ultra-high performance concrete(UHPC).Through FEM analysis and static and dynamic bending fatigue tests of the composite structure,the influences of the interface of the pavement layer,reinforcement,and different paving materials on the structural performance were compared and *** results show that the resin bonded UHPC pavement structure can reduce the weld strain in the steel plate by about 32%and the relative deflection between ribs by about 52%under standard axial load conditions compared to traditional *** EP bonding layer can nearly double the drawing strength of the pavement interface from 1.3 MPa,and improve the bending resistance of the UHPC structure on steel bridge decks by about 50%;the bending resistance of reinforced UHPC structures is twice that of unreinforced UHPC structure,and the dynamic deflection of the UHPC pavement structure increases exponentially with increasing fatigue *** fatigue life is about 1.2×10^(7) cycles under a fixed force of 9 kN and a dynamic deflection of 0.35 mm,which meets the requirements for fatigue performance of pavements on steel bridge decks under traffic conditions of large flow and heavy load.

关键词： steel bridge deck pavement ultra-high-performance concrete epoxy resin composite structure bending fatigue performance

Component Optimization and Seepage Simulation Method of resin Based Permeable Brick

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Journal of Renewable Materials 2020年第8期8卷 947-968页

作者： Xiaofu Wang Xiong Zhang Yan He Chunming Lian Key Laboratory of Advanced Civil Engineering Materials of Education Ministry School of Material Science and TechnologyTongji UniversityShanghai201804China School of Civil Engineering Suzhou University of Science and TechnologySuzhou215011China China Construction Eighth Engineering Bureau Co. Ltd.Shanghai200122China

In order to solve the problem of urban surface runoff,it is necessary to study permeable brick *** test and DMA test were used to study the binder material of permeable brick,and a material with the best mechanical properties was selected as the binder of resin based permeable brick;The permeable brick with single gradation and continuous gradation and porosity of 0.1–0.5 gradient is constructed by 3D modeling *** particle composition and the seepage simulation results of permeable brick under different design parameters were analyzed;A resin-based permeable brick with micro-pores was prepared using the selected binder and desert sand with high roundness as aggregate,and compared with the simulation,its water permeability coefficient is 3.25×10-2 cm/s and the compressive strength is 36.19 *** the seepage simulation of permeable brick,it is known that with the increase of gradation width“value i”,the water permeability coefficient ***,in order to control the number of aggregate particles and obtain better seepage performance,the wide gradation of i≥4 and the design porosity of 0.3–0.4 should be *** study provides a research basis and a simulation method for the component optimization of resin based permeable brick.

关键词： Permeable brick epoxy resin aggregate sponge city

硅橡胶环氧树脂复合材料电痕的实验研究(英文)

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高电压技术 2011年第11期37卷 2780-2785页

作者： Abdul Syakur Hamzah Berahim Tumiran Rochmadi Department of Electrical Engineering Gadjah Mada UniversityYogyakarta 55281Indonesia Department of Chemical Engineering Gadjah Mada UniversityYogyakarta 55281Indonesia

The use of polymer materials as electrical insulators on transmission and distribution lines has been increasing such as epoxy *** advantages of using epoxy resin as an insulating material are its low density,better dielectric properties,and epoxy resin has higher volume resistivity than that of the glass and ***,epoxy resin has some disadvantages when it is used in tropical areas concerning with the humidity,high ultraviolet radiation, acid rain and effects of ***,insulator surface will be easily damaged due to electrical tracking,which is indicated by the surface *** this paper,the surface tracking on epoxy resin compound with silicon rubber has been *** test was done based on the method of Inclined-Planed Tracking(IPT) IEC 587:1984 with NH_4C1 as *** test materials used were epoxy resins based on Diglycidyl Ether of Bisphenol A(DGEBA) and Methaphenylene Diamine(MPDA) compound with silicon rubber(SiR) with the dimensions of 50 mm×120 mm and the thickness of 6 *** flow rate of contaminant was 0.3 mL/*** 3.5 kV AC high voltage 50 Hz was applied to the top *** experimental results show that the contact angle of hydrophobic was affected by compound of silicon *** surface tracking,time to tracking and discharge current were affected by applied voltage,contamination and contact *** using micro-cameras,the surface damage was detected. The severest damaged sample surface on a sample had small contact *** the other hand,samples with the greatest contact angle needed longer time to have surface damage in the surface *** shows that it is more difficult for large contact angle samples or more hydrophobic to have surface *** resin compound with silicon rubber has contact angle of hydrophobic greater than epoxy resin without silicon rubber.

关键词： epoxy resin silicon rubber tracking contact angle discharge current contaminant

Mechanical properties of short carbon/glass fiber reinforced high mechanical performance epoxy resins

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Journal of Chongqing University 2009年第4期8卷 222-230页

作者：张竞黄培 State Key Laboratory of Materials-oriented Chemical Engineering College of Chemistry and Chemical EngineeringNanjing University of Technology

To research the relationship between epoxy and fiber inherent property and mechanical properties of composite,we prepared a series of composites using three kinds of high mechanical performance epoxy resins as matrices and reinforced by the same volume fraction(5%)of short carbon and glass *** mechanical properties were investigated from the perspective of chemical structure and volume shrinkage ratio of *** analyzed their tensile strength and modulus based on the mixing rule and Halpin-Tsai eq...

关键词： epoxy resin matrix fibers composites mechanical properties