scholarly journals The Influence of Mixing Methods of Epoxy Composition Ingredients on Selected Mechanical Properties of Modified Epoxy Construction Materials

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 411
Author(s):  
Izabela Miturska ◽  
Anna Rudawska ◽  
Miroslav Müller ◽  
Monika Hromasová
Keyword(s):  
Tensile Strength ◽  
Epoxy Resin ◽  
Construction Materials ◽  
Preliminary Heating ◽  
Epoxy Composition ◽  
Mixing Speed ◽  
Adhesive Composition ◽  
Adhesive Compositions ◽  
The Matrix ◽  
Level Of Significance

The proper process of preparing an adhesive composition has a significant impact on the degree of dispersion of the composition ingredients in the matrix, as well as on the degree of aeration of the resulting composition, which in turn directly affects the strength and functional properties of the obtained adhesive compositions. The paper presents the results of tensile strength tests and SEM microphotographs of the adhesive composition of Epidian 57 epoxy resin with Z-1 curing agent, which was modified using three fillers NanoBent ZR2 montmorillonite, CaCO3 calcium carbonate and CWZ-22 active carbon. For comparison purposes, samples made of unmodified composition were also tested. The compositions were prepared with the use of six mixing methods, with variable parameters such as type of mixer arm, deaeration and epoxy resin temperature. Then, three mixing speeds were applied: 460, 1170 and 2500 rpm. The analyses of the obtained results showed that the most effective tensile results were obtained in the case of mixing with the use of a dispersing disc mixer with preliminary heating of the epoxy resin to 50 °C and deaeration of the composition during mixing. The highest tensile strength of adhesive compositions was obtained at the highest mixing speed; however, the best repeatability of the results was observed at 1170 rpm mixing speed. Based on a comparison test of average values, it was observed that, in case of modified compositions, the values of average tensile strength obtained at mixing speeds at 1170 and 2500 rpm do not differ significantly with the assumed level of significance α = 0.05.

scholarly journals Starch-jute fiber hybrid biocomposite modified with an epoxy resin coating: fabrication and experimental characterization

2018 ◽  
Vol 27 (5-6) ◽  
Author(s):  
Akarsh Verma ◽  
Kamal Joshi ◽  
Amit Gaur ◽  
V. K. Singh
Keyword(s):  
Tensile Strength ◽  
Epoxy Resin ◽  
Tensile Tests ◽  
Epoxy Coating ◽  
Jute Fiber ◽  
Experimental Characterization ◽  
Compression Moulding ◽  
Major Disadvantage ◽  
The Matrix ◽  
Epoxy Resin Coating

AbstractIn this article, biocomposites derived from a starch-glycerol biodegradable matrix reinforced with jute fibers were fabricated using the wet hand lay-up and compression moulding techniques. Samples having different weight percentages of jute fiber in the starch matrix were analyzed. The fiber’s surface was chemically treated by alkaline sodium hydroxide to improve the interphase bonding between the fiber and the matrix. Tensile tests for the composites were done and the sample with highest tensile strength was selected for further tests that included water absorption (WA), scanning electron microscopy (SEM) and thermal analysis (TA). It has been concluded that the ultimate tensile strength was found to be maximum for the composition of 15% fiber by weight composite as 7.547 MPa without epoxy coating and 10.43 MPa with epoxy coating. The major disadvantage of the biocomposite is its high WA property, which in this study was inhibited by the epoxy resin layer. Herein, the results of various tests done disclose a noteworthy improvement in the overall properties of bio-composite, in comparison to the neat biodegradable starch matrix.

Physics-mechanical and viscoelastic properties of polymer compositions based on synthetic oligomer ED-20 and epoxidized soybean oil

2021 ◽  
Vol 43 (2) ◽  
pp. 95-102
Author(s):  
L.A. Gorbach ◽  
◽  
N.V. Babkina ◽  
O.G. Purikova ◽  
A.V. Barantsova ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Soybean Oil ◽  
Epoxy Resin ◽  
Viscoelastic Properties ◽  
Relative Elongation ◽  
Crosslinking Density ◽  
Epoxidized Soybean Oil ◽  
Premature Failure ◽  
Epoxy Composition

The work was aimed at studying the effects of combining epoxidized soybean oil (ESO) with standard bisphenol type A epoxy resin (ED-20). The ED-20 / ESO ratios were 100/0, 90/10, 95/15 and 80/20 (wt%). The system was cured with amine hardener mono(cyanethyl) diethylenetriamine (MCDT), triethanolamine (TEA) and mixture thereof (TEA + MCDT) at different curing temperatures. The choice was based on the hardener’s ability to open oxirane cycles, form a spatial network and initiate several parallel reactions. The viscoelastic properties, mechanical properties (tensile strength and elongation) were studied the density of obtained ED-20 / ESO samples was determined. The results showed that the introduction of ESO into epoxy resin ED-20 was accompanied by significant changes in the curing and final properties of the samples. It was shown that the physic- mechanical properties of polymer compositions ED-20 / ESO were determined by both the ESO content and the temperature of curing Depending on the selected curing mode, the addition of 5–10 wt.% of ESO increased the tensile strength relative to the σр value of the original epoxy matrix. The values of relative elongation increased significantly at 15-20 wt.% of ESO. By the method of dynamic mechanical analysis it was shown that the increase of ESO content leads to plasticization of epoxy composition and to reduction of crosslinking density. It was determined that 5-10 wt.% was the optimal concentration of ESO, at which the epoxy composition had improved physical and mechanical properties Further increase of ESO content reduced the crosslinking density and increased the defectiveness of the epoxy polymer, which causes premature failure in weak places of the structure under load.

Epoxy composites reinforced with multi-walled carbon nanotube/poly(ethylene glycol)methylether-coated aramid fiber

2016 ◽  
Vol 36 (5) ◽  
pp. 465-471 ◽  
Author(s):  
Ayesha Kausar ◽  
Muhammad Siddiq
Keyword(s):  
Tensile Strength ◽  
Flexural Strength ◽  
Ethylene Glycol ◽  
Epoxy Resin ◽  
Aramid Fiber ◽  
Aramid Fibers ◽  
Poly Ethylene Glycol ◽  
Scanning Calorimetry ◽  
The Matrix ◽  
Poly Ethylene

Abstract A novel type of aramid fibers coated with poly(ethylene glycol) methyl ether (PEGME)-modified multi-walled carbon nanotubes (MWCNTs) was designed using electrophoresis. Owing to the good interaction of MWCNT-PEGME with the matrix, the coated fibers were well dispersed in epoxy resin. Thin films of epoxy/aramid-MWCNT-PEGME were prepared by placing the modified aramid fibers in molds, and the epoxy resin was infused into them. 4,4′-Diaminodiphenylmethane was dissolved in epoxy before the resin was poured over the aramid fibers coated with MWCNT-PEGME. According to fracture surface studies, the modified fibers were completely miscible with the epoxy resin and the filler was dispersed well in the space between the aramid fibers. The tensile strength of neat resin was increased from 658 to 1198 MPa in 40 wt.% of fiber-loaded epoxy/aramid-MWCNT-PEGME 40 composite. The maximum flexural strength was also found to be higher for epoxy/aramid-MWCNT-PEGME 40 (1593 MPa). The glass transition temperature (Tg) was studied using differential scanning calorimetry, in the range of 164–173°C. The tensile strength, modulus, flexural strength, and Tg of epoxy/aramid fiber composites with unmodified fibers were found to be lower than those of epoxy/aramid-MWCNT-PEGME composites.

Preparation and Properties of Silicone Modified Epoxy Resin, Nano-TiO2 and Nano-TiO2/Micron-Al2O3 Polymer Alloys Putty

2011 ◽  
Vol 239-242 ◽  
pp. 3009-3013
Author(s):  
Ming Qiu Wang ◽  
Jun Yan ◽  
Hai Ping Cui ◽  
Shi Guo Du
Keyword(s):  
Tensile Strength ◽  
Epoxy Resin ◽  
Friction And Wear ◽  
Room Temperature ◽  
Mass Ratio ◽  
Friction Mechanism ◽  
The Matrix ◽  
Pin On Disk ◽  
Modified Epoxy ◽  
Friction And Wear Characteristics

The epoxy resin-based polymer alloys putty modified by using silicone/nano-TiO2/MoS2micron-particles and nm-TiO2/μm-Al2O3composite particles were prepared at room temperature. Properties including hardness, friction and wear characteristics are analyzed by means of pin-on-disk testers, scanning electron microscopy (SEM). In addition, the influences of contents of organic silicone on the matrix were investigated via measuring the tensile strength and elongation, thermal stability and microstructure of the cured materials. The results showed that the tensile strength of the cured materials(mass ratio of epoxy resin to TSR144 is 1:1) is 59.12 MPa, elongation = 12.40%, and temperature of 50% weight loss is 414°C, higher than those of pure epoxy resin by 10.58 MPa, 5.59%, and 24°C respectively. Finally, its friction mechanism has been preliminarily discussed.

Morphology of High-Performance Rigid-Rod Polymer Fibers and Molecular Composites

1989 ◽  
Vol 47 ◽  
pp. 338-339
Author(s):  
W.W. Adams ◽  
S. J. Krause
Keyword(s):  
Tensile Strength ◽  
High Performance ◽  
Liquid Crystalline ◽  
Molecular Level ◽  
Synergistic Effects ◽  
Tensile Modulus ◽  
Commercial Development ◽  
The Matrix ◽  
Molecular Composites ◽  
Rigid Rod

Rigid-rod polymers such as PBO, poly(paraphenylene benzobisoxazole), Figure 1a, are now in commercial development for use as high-performance fibers and for reinforcement at the molecular level in molecular composites. Spinning of liquid crystalline polyphosphoric acid solutions of PBO, followed by washing, drying, and tension heat treatment produces fibers which have the following properties: density of 1.59 g/cm3; tensile strength of 820 kpsi; tensile modulus of 52 Mpsi; compressive strength of 50 kpsi; they are electrically insulating; they do not absorb moisture; and they are insensitive to radiation, including ultraviolet. Since the chain modulus of PBO is estimated to be 730 GPa, the high stiffness also affords the opportunity to reinforce a flexible coil polymer at the molecular level, in analogy to a chopped fiber reinforced composite. The objectives of the molecular composite concept are to eliminate the thermal expansion coefficient mismatch between the fiber and the matrix, as occurs in conventional composites, to eliminate the interface between the fiber and the matrix, and, hopefully, to obtain synergistic effects from the exceptional stiffness of the rigid-rod molecule. These expectations have been confirmed in the case of blending rigid-rod PBZT, poly(paraphenylene benzobisthiazole), Figure 1b, with stiff-chain ABPBI, poly 2,5(6) benzimidazole, Fig. 1c A film with 30% PBZT/70% ABPBI had tensile strength 190 kpsi and tensile modulus of 13 Mpsi when solution spun from a 3% methane sulfonic acid solution into a film. The modulus, as predicted by rule of mixtures, for a film with this composition and with planar isotropic orientation, should be 16 Mpsi. The experimental value is 80% of the theoretical value indicating that the concept of a molecular composite is valid.

Mechanical characterization of LM25 alloy matrix composite reinforced with boron carbide

2021 ◽  
pp. 002199832110055
Author(s):  
Zeeshan Ahmad ◽  
Sabah Khan
Keyword(s):  
Tensile Strength ◽  
Boron Carbide ◽  
Mechanical Characterization ◽  
Stir Casting ◽  
Surface Mapping ◽  
Alloy Matrix ◽  
Casting Technique ◽  
The Matrix ◽  
Carbide Particles

Alumnium alloy LM 25 based composites reinforced with boron carbide at different weight fractions of 4%, 8%, and 12% were fabricated by stir casting technique. The microstructures and morphology of the fabricated composites were studied by scanning electron microscopy and energy dispersive spectroscopy. Elemental mapping of all fabricated composites were done to demonstrate the elements present in the matrix and fabricated composites. The results of microstructural analyses reveal homogenous dispersion of reinforcement particles in the matrix with some little amount of clustering found in composites reinforced with 12% wt. of boron carbide. The mechanical characterization is done for both alloy LM 25 and all fabricated composites based on hardness and tensile strength. The hardness increased from 13.6% to 21.31% and tensile strength 6.4% to 22.8% as reinforcement percentage of boron carbide particles increased from 0% to 12% wt. A fractured surface mapping was also done for all composites.

scholarly journals Enhanced Tensile Strength of Monolithic Epoxy with Highly Dispersed TiO2-Graphene Nanocomposites

2021 ◽  
Vol 5 (7) ◽  
pp. 191
Author(s):  
Yanshuai Wang ◽  
Siyao Guo ◽  
Biqin Dong ◽  
Feng Xing
Keyword(s):  
Tensile Strength ◽  
Epoxy Resin ◽  
Mechanical Performance ◽  
Chemical Properties ◽  
High Mechanical Property ◽  
Graphene Nanocomposites ◽  
Highly Dispersed ◽  
Dispersion State ◽  
Physical And Chemical

The functionalization of graphene has been reported widely, showing special physical and chemical properties. However, due to the lack of surface functional groups, the poor dispersibility of graphene in solvents strongly limits its engineering applications. This paper develops a novel green “in-situ titania intercalation” method to prepare a highly dispersed graphene, which is enabled by the generation of the titania precursor between the layer of graphene at room temperature to yield titania-graphene nanocomposites (TiO2-RGO). The precursor of titania will produce amounts of nano titania between the graphene interlayers, which can effectively resist the interfacial van der Waals force of the interlamination in graphene for improved dispersion state. Such highly dispersed TiO2-RGO nanocomposites were used to modify epoxy resin. Surprisingly, significant enhancement of the mechanical performance of epoxy resin was observed when incorporating the titania-graphene nanocomposites, especially the improvements in tensile strength and elongation at break, with 75.54% and 176.61% increases at optimal usage compared to the pure epoxy, respectively. The approach presented herein is easy and economical for industry production, which can be potentially applied to the research of high mechanical property graphene/epoxy composite system.

scholarly journals Dual UV-Thermal Curing of Biobased Resorcinol Epoxy Resin-Diatomite Composites with Improved Acoustic Performance and Attractive Flame Retardancy Behavior

2021 ◽  
Vol 2 (1) ◽  
pp. 24-48
Author(s):  
Quoc-Bao Nguyen ◽  
Henri Vahabi ◽  
Agustín Rios de Anda ◽  
Davy-Louis Versace ◽  
Valérie Langlois ◽  
...  
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Epoxy Resin ◽  
Flame Retardancy ◽  
Sound Absorption ◽  
Flexural Modulus ◽  
Construction Materials ◽  
Acoustic Properties ◽  
Low Frequencies ◽  
Compacting Pressure

This study has developed novel fully bio-based resorcinol epoxy resin–diatomite composites by a green two-stage process based on the living character of the cationic polymerization. This process comprises the photoinitiation and subsequently the thermal dark curing, enabling the obtaining of thick and non-transparent epoxy-diatomite composites without any solvent and amine-based hardeners. The effects of the diatomite content and the compacting pressure on microstructural, thermal, mechanical, acoustic properties, as well as the flame behavior of such composites have been thoroughly investigated. Towards the development of sound absorbing and flame-retardant construction materials, a compromise among mechanical, acoustic and flame-retardant properties was considered. Consequently, the composite obtained with 50 wt.% diatomite and 3.9 MPa compacting pressure is considered the optimal composite in the present work. Such composite exhibits the enhanced flexural modulus of 2.9 MPa, a satisfying sound absorption performance at low frequencies with Modified Sound Absorption Average (MSAA) of 0.08 (for a sample thickness of only 5 mm), and an outstanding flame retardancy behavior with the peak of heat release rate (pHRR) of 109 W/g and the total heat release of 5 kJ/g in the pyrolysis combustion flow calorimeter (PCFC) analysis.

scholarly journals Study on the Dissolution and Precipitation Behavior of Self-Designed (NbTi)C Nanoparticles Addition in 1045 Steel

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 184
Author(s):  
Hongwei Zhu ◽  
Haonan Li ◽  
Furen Xiao ◽  
Zhixiang Gao
Keyword(s):  
Tensile Strength ◽  
Electron Microscope ◽  
Optical Microscope ◽  
Cast Steels ◽  
Uniform Dispersion ◽  
The Matrix ◽  
Thermo Calc Software ◽  
Particle Strengthening ◽  
1045 Steel ◽  
Addition Amount

Self-designed (NbTi)C nanoparticles were obtained by mechanical alloying, predispersed in Fe powder, and then added to 1045 steel to obtain modified cast steels. The microstructure of cast steels was investigated by an optical microscope, scanning electron microscope, X-ray diffraction, and a transmission electron microscope. The results showed that (NbTi)C particles can be added to steels and occur in the following forms: original ellipsoidal morphology nanoparticles with uniform dispersion in the matrix, cuboidal nanoparticles in the grain, and microparticles in the grain boundary. Calculations by Thermo-Calc software and solubility formula show that cuboidal (NbTi)C nanoparticles were precipitated in the grain, while the (NbTi)C microparticles were formed by eutectic transformation. The results of the tensile strength of steels show that the strength of modified steels increased and then declined with the increase in the addition amount. When the addition amount was 0.16 wt.%, the modified steel obtained the maximum tensile strength of 759.0 MPa, which is an increase of 52% compared with to that with no addition. The hardness of the modified steel increased with the addition of (NbTi)C nanoparticles. The performance increase was mainly related to grain refinement and the particle strengthening of (NbTi)C nanoparticles, and the performance degradation was related to the increase in eutectic (NbTi)C.

Sign in / Sign up

Export Citation Format

Share Document