Effect Of Epoxy Resin Research Articles

Effects of epoxy resin on the mechanical performance and thickening properties of geopolymer cured at low temperature

The research objectives were to investigate the influence of waterborne bisphenol-A epoxy resin on mechanical performance and thickening properties of metakaolin-slag based geopolymer at 10°C. Test results showed that the epoxy resin has ability to decrease the thickening time, while the benzyl glycidyl ether diluent can prolong thickening time. Hydration heat test was performed to explain the different consistency increasing trend of pure geopolymer and hybrid composite samples. Epoxy equivalent analysis was carried out to explain the mechanism of dilution effect on thickening time. The 1-day compressive strength of geopolymer was reinforced by doping epoxy resin, but the 3-day strength was lower than pure geopolymer when the doping amount of epoxy resin was below 50%. The morphology and quantitative element results revealed that the homogenous and high degree of miscibility led to dense and uncracked morphology. In order to enhance the durability of cement sheath under deep water strata stress wave condition, we should increase the dosage of ER to achieve low Young's modulus. The benzyl glycidyl ether diluent is recommended to make thickening time adjustable and to reinforce the compressive strength. This novel material makes the geopolymer-based composites applicable for oil wells cementation at low temperatures.

Effect of epoxy resin and hardener containing microcapsules on healing efficiency of epoxy adhesive based metal joints

Dual component microcapsules of epoxy resin and polyamine hardener with polymethyl methacrylate (PMMA) shell were synthesized using a water-oil-water emulsion solvent evaporation method. The high concentration of sodium dodecyl sulfate (SDS) was used to reduce the thickness of shell wall of dual component microcapsules. The dual microcapsules of 1:1 weight ratio were introduced in the epoxy adhesive to study the healing effect. The morphology, chemical structure and thermal characteristics of the microcapsules were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA), respectively. The insertion of dual component microcapsules in epoxy matrix reduced the lap shear strength of adhesive joints, which may be attributed to the generation of stress concentration cites because of micron sized capsules. However, the extension and absorbed failure energy of adhesive joints under uniaxial loading increased with the increase of concentration of dual microcapsules. The viscoelastic nature of the dual microcapsules may be responsible for this enhancement. Significant enhancement in the healing efficiency (90.93%) of the joints was achieved for 10 wt% of dual microcapsules. The crack pinning and crack blunting mechanisms at the vicinity of the crack path adjacent to the microcapsules were found responsible for significant enhancement in the healing efficiency of the adhesive joints.

Effect of epoxy resin on the thermal, mechanical and rheological properties of polybutylene terephthalate/glycidyl methacrylate functionalized methyl methacrylate-butadiene blend

Epoxy resin was used to modify polybutylene terephthalate(PBT) and glycidyl methacrylate functionalized methyl methacrylate-butadiene(MB-g-GMA) blend. Results show that MB-g-GMA dispersed in PBT matrix uniformly and PBT/MB-g-GMA/epoxy blends reveal good compatibility. However, the added epoxy resin restricted the mobility of PBT macromolecular chains during the growth process of the crystal, which reduced the final crystallinity of PBT. The PBT/MB-g-GMA blend containing 1%(mass fraction) epoxy resin exhibited good mechanical properties. For example, the notched impact strength of the PBT/MB-g-GMA blend with 1%(mass fraction) epoxy resin was about 2 times that of PBT/MB-g-GMA blend. Sanning electron microscope(SEM) results show that the shear yielding of the PBT matrix and the cavitations of rubber particles were the major toughening mechanisms. The chemical reaction between PBT and epoxy resin induced the high complex viscosity and storage modulus of PBT/MB-g-GMA blend.

Study on the Effects of Epoxy Resin Based Polymer Dispersed Liquid Crystal Films Using Polythiol Group (–SH) as Hardener and Catalyst

Study on the Effects of Epoxy Resin Based Polymer Dispersed Liquid Crystal Films Using Polythiol Group (–SH) as Hardener and Catalyst

Facile fabrication and modification of epoxy acrylate latexes by epoxy resin and silane coupling agent

For the purpose of obtaining solvent-free epoxy acrylate latexes of good stability and excellent integrated performance, the epoxy acrylate latexes were fabricated using facile semi-continuous emulsion polymerization with varying amounts of epoxy resin and were modified by a silane coupling agent γ-methacryloxypropyltrimethoxysilane (KH-570). The effects of epoxy resin and KH-570 amounts on the performance of latexes and films were investigated from the aspects of particle size, morphology, tensile measurements, resistance properties, adhesion force, and thermal behavior. The results indicated that the acrylate monomers did graft onto the molecular chain of E-51 characterized by both epoxy value and Fourier transform infrared. Additionally, an emulsion of 80–100 nm particle size with a narrow distribution was obtained. The latex films retain resistances to satisfactory water, acid, alkali, and alcohol while maintaining good thermal stability, adhesion force, and flexibility. The importing of KH-570 could reinforce the spatial structure and cross-linking density and then improve the tensile strength of the latex films properly while keeping other performances well. This work provides a facile pathway for the optimized performance for epoxy acrylate latexes, and represents a tendency for environmental protection.

Kinetic study of the stabilizing effect of aluminum trihydroxide on thermal degradation of epoxy resin

AbstractThe stabilizing effect of epoxy resin (EP)/aluminum trihydroxide (ATH) was measured by thermogravimetric analysis (TGA) in an N2 flow. The Kissinger and Flynn-Wall-Ozawa methods were used to determine the activation energy of non-isothermal degradation at different stages. The results showed that there was a slight increase in activation energy after ATH was added. It confirms the fire-retardant effect of ATH on the thermal degradation behaviour of pure EP. The Flynn-Wall-Ozawa method showed that flame-retardant ATH remarkably enhanced the activation energy of the thermal degradation process for EP, albeit the conversion rate being only 10%, which demonstrated the stabilization of ATH to the char layer of EP.

Effects of Epoxy Resin on Gelcasting Process and Mechanical Properties of Alumina Ceramics

A gelling system based on the polymerization of epoxy resin ethylene glycol diglycidyl ether (EGDGE) and 3,3′‐Diaminodipropylamine (DPTA) was developed for gelcasting alumina ceramics. The gelation process of 50 vol% alumina‐epoxy resin suspensions were investigated in accordance with the change in temperature and epoxy resin concentration. The activation energy Ea of polymerization reaction was 63.76 kJ/mol and no significant gelation was observed at 25°C during the test for 50 vol% Al2O3 suspensions with 10 wt% EGDGE. With the increase in EGDGE concentration, Al2O3 green bodies exhibited higher relative density, flexural strength, and Weibull modulus, reaching 64.4%, 41.03 MPa, and 12.51, respectively, when EGDGE concentration was 20 wt%. However, for sintered Al2O3 bodies, the highest characteristic strength and Weibull modulus were obtained for 15 wt% EGDGE concentration, reaching 367.57 MPa and 14.52, respectively.

Effect of epoxy resin on the intrinsic properties of masonry mortars

The paper presents an assessment on the properties of three different types of masonry mortars, namely Portland cement mortar (CM), polymer cement mortar (PCM) and polymer mortar (PM) of various compositions. The effect of binder content (cement and/or epoxy) on CM, PCM or PM has been explored in the study. An assessment was carried out on the basis of mechanical (compressive, tensile and flexural strength), physical (water uptake, chloride ion permeability), morphological (porosity) and thermal (coefficient of thermal expansion) properties of the mortars. A comparative cost analysis of the mortars is also discussed in this article. The results show that the mechanical strength of both PCM and PM improves markedly with the addition of epoxy resin, and the higher rate of incremental strength is found for PM. Consequently, the chloride ion penetration, water uptake, porosity and thermal expansion of the mortars decrease significantly with the resin content, but the rate of drop in chloride ion penetration, water uptake, porosity and thermal expansion is much higher for PM. The test results indicate that the variation of binder content (epoxy/cement) is found to be the key factor determining the mortar properties and cost.

A Laboratory Investigation into the Composite Bonding System of Cement-Emulsified Asphalt-Epoxy Resin

The objective of this article is to provide an insight into a new composite bonding system of Cement/emulsified-Asphalt/Epoxy resin (CAE) for steel box girder bridge pavement. The effect of epoxy resin on emulsified asphalt mixtures added with cement has been investigated in laboratory. Besides the mechanical properties of mixtures using CAE binders, the microscopic feature of CAE binders also have been measured. The results of mechanical tests indicate good performances for pavement, especially rutting deformation at high temperature and adhesive strength with steel blocks. Then, microscopic images show some interesting microscopic feature, which could be related to the development of performances.

Thermomechanical properties of arylamine‐based benzoxazine resins alloyed with epoxy resin

AbstractEffects of epoxy resin on various arylamine‐based benzoxazine resins, i.e., aniline (BA‐a), m‐toluidine (BA‐mt), and 3,5‐xylidine (BA‐35x), have been investigated. Processing windows of BA‐35x, BA‐mt, and BA‐a were found to be widened with the amount of the epoxy. Gel points of benzoxazine‐epoxy resin mixtures can be predicted by an Arrhenius equation, e.g., gel time of BA‐35x and epoxy mixture at 70:30 mass ratio can be estimated by tgel = 0.7012 × 10−7 exp (10.563/T). Glass transition temperature (Tg) of BA‐a and BA‐mt alloyed with epoxy exhibited a synergistic behavior with the maximum Tg value at the benzoxazine‐epoxy composition of 80:20 mass ratio. However, in the BA‐35x and epoxy mixture, the decreasing trend in Tg from 241°C to 223°C with an addition of epoxy was observed. Furthermore, flexural strength and strain‐at‐break of those alloys were found to increase with increasing amount of the epoxy while modulus increased with the polybenzoxazine mass fraction. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers

The effect of epoxy‐polyester hybrid resin on mechanical properties, rheological behavior, and water absorption of polypropylene wood flour composites

AbstractThe effect of epoxy resin on mechanical and Rheological properties, and moisture absorption of wood flour polypropylene composites (WPCs) were investigated. The reactive mixing of epoxy resin with 30, and 40 wt% wood flour and polypropylene (PP) was carried out in twin screw extruder with a special screw elements arrangement. PP grafted maleic anhydrides (MPP) were used as coupling agent to improve the interfacial interactions of wood flour, epoxy resin, and PP. The tensile strength of composites decreased, and elastic modulus and moisture absorption increased with increasing epoxy resin content. The complex viscosity η* increased with increasing epoxy resin content of composites, and a synergistic effect in increasing the η* was observed at 3 wt% resin. The epoxy resin modified wood‐PP composites that chemically coupled by MPP showed minimum water absorption with highest elastic modulus. The experimental oscillation rheologyical data were used to drive a model to predict the flow behavior of WPCs, in a wide range of frequencies. POLYM. ENG. SCI., 47:2041–2048, 2007. © 2007 Society of Plastics Engineers

Lifetime Improvement of Glucose Biosensor by Epoxy‐Enhanced PVC Membrane

AbstractA new approach using epoxy resin to enhance the durability and adhesion of a diffusion‐limiting membrane in amperometric biosensors is described. The polymer membrane was mainly composed of commercially available fast epoxy adhesive ATACS 5104, poly(vinyl chloride) (PVC) and plasticizers such as isopropyl myristate (IMP) and Aliquat 336 (AL). It can be readily deposited on various substrates by using coating and other thin film fabrication methods. The effect of epoxy resin in the membrane composition was investigated using a coil‐type glucose biosensor containing extra enzyme. The ideal membrane was found to include approximately 1/3 epoxy resin, 1/3 plasticizer and 1/3 PVC. Such a membrane was verified to be porous and permeable to small molecules like glucose and can tightly adhere to other beneath layers such as a Nafion membrane, which serves as the interference‐eliminating layer. These epoxy‐based glucose biosensors showed excellent electrochemical response properties including a long lifetime and can be used for microanalysis of solutions and biological fluids. With an additional PU outermost layer, the present glucose biosensors can potentially be used for in vivo measurements.

Structural-mechanical relationship of epoxy compatibilized polyamide 6/polycarbonate blends

Polyamide 6 (PA6)/polycarbonate (PC) blends compatibilized with solid epoxy resin (bisphenol type-A) were prepared by extrusion followed by injection molding. The effects of epoxy resin on the microstructure, tensile, impact and compatibility of the PA6/PC blends were investigated. The results showed that both the tensile modulus and elongation at break of PA6/PC blends were inferior as compared to their parent polymers. This resulted from incompatibility between the PA6 and PC phases. SEM observation revealed that the introduction of 0.5 part per hundred (phr) epoxy resin into the PA6/PC75/25 blend yields a finer dispersion of PC phase in PA6 matrix. The boundaries between the PC domains and PA6 matrix became obscure with the incorporation of 1 phr epoxy resin. Such an improvement in compatibility was suggested to be resulted from the formation of in situ epoxy bridged PA6-PC block copolymer in the blend during compounding. Consequently, the tensile modulus, yield strength and impact strength of the PA6/PC 75/25 blend improved considerably with increasing epoxy content.

Effect of epoxy resin on morphology and physical properties of PVC/organophilic montmorillonite nanocomposites

AbstractPoly(vinyl chloride)/organophilic montmorillonite (PVC/OMMT) nanocomposites were prepared by means of melt blending. A liquid epoxy resin was used to aid PVC chains in intercalating into silicate layers. The effects of the preparation methods and epoxy resin contents on the melt intercalation of PVC were investigated. The morphology development, mechanical properties and optical properties of the PVC/OMMT composites were tested as functions of epoxy resin content and OMMT content. Wide‐angle X‐ray diffraction, transmission electron microscopy and scanning electron microscopy were used to characterize the morphology of the resulting composites. After being pretreated by the epoxy resin, the OMMT layers were largely intercalated into the PVC matrix, and even exfoliated at high epoxy resin content. The addition of epoxy resin led to a decrease in optical clarity of the composites but improved the processing stability, as indicated by yellowness index and haze measurement. However, the optical clarity of the composites containing 4 phr of epoxy resin (PVC/E‐OMMT) was improved by increasing the OMMT content, as shown by light transmission. Both the tensile strength and notched Izod impact strength of the PVC/E‐OMMT composites reached their maximum values when the OMMT content was 0.5 phr and the epoxy resin content was 2 phr. With further increase of the OMMT content and the epoxy resin content, the tensile strength decreased but was still higher than that of original PVC. The method of addition of epoxy resin had little effect on the physical properties but mainly influenced the morphology of PVC/OMMT nanocomposites. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2184–2191, 2003

Effects of epoxy resin on mechanical and thermal characteristics of poly(propylene oxide)/poly(butyl acrylate) networks

We report mechanical and thermal characteristics of a network composed of poly(propylene oxide) (PPG) and poly(butyl acrylate) crosslinked with tolylene diisocyanate. It was found that addition of about 4 wt % of an epoxy resin resulted in a higher mechanical toughness and less discoloration. Furthermore, it was found that the epoxy has a self-restoration function against thermal degradation of the network. The reaction mechanism between the network and the epoxy was investigated with infrared spectroscopy and 13C-NMR and the effect of the epoxy resin on the thermal stability and physical properties is discussed. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 1886–1893, 2000

酸化銀電池の電解液漏洩封止に関する研究 （第４報） 水素ガス発生抑止による封止法の開発

Mixture of epoxy resin and asphalt was used as sealant, which existed between the gasket and anode can, in the silver oxide battery. Best mixing ratio among epoxy resin, hardener and asphalt was proposed, and two reasons that the mixture of epoxy resin and asphalt show good seal characteristics are shown in this experiment. One of the reasons is that the mixture worked as soft material between gasket and can to decrease the clearances. Another reason is that the creep of alkaline on copper surface is decreased by the effect of epoxy resin. It has been proven that the mixture of epoxy resin and asphalt has good characteristics for sealing alkaline electrolyte by the mass production batteries. Absorbing the diphenylcarbazide to anode can copper surface brought out good seal characteristics for the silver oxide batteries. In conclusion, the mechanism of leakage of the silver oxide battery is that the electrolyte invades into clearances between the seal consisted by gasket and anode can and it generated hydrogen gas on copper surface, which made gas hall and leak path. It has also been proven that decreasing hydrogen gas generation is one of the most important ways to get better sealing.

The effect of epoxy resin and polyamine hardener on the photo-fading of 2-piperidinoanthraquinone in solution: A flash photolysis study

The triplet state of 2-piperidinoanthraquinone has been generated in toluene solutions using nanosecond laser flash photolysis. The effect of epoxy resin and polyamine hardener on the yield and lifetimes of the dye triplet state and the dye semiquinone species has been studied. For both resin and hardener, dye semiquinone species are produced which subsequently disproportionate to yield the hydroquinone and so cause photo-fading. The mechanisms by which these free radicals are formed and their relevance to the photo-fading of dyed epoxy resin are discussed in detail.