scholarly journals Synergetic Effects of Silver Nanowires and Graphene Oxide on Thermal Conductivity of Epoxy Composites

Nanomaterials ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 1264 ◽  
Author(s):  
Li Zhang ◽  
Wenfeng Zhu ◽  
Ying Huang ◽  
Shuhua Qi
Keyword(s):  
Thermal Conductivity ◽  
Graphene Oxide ◽  
Impact Strength ◽  
Epoxy Resin ◽  
Silver Nanowires ◽  
Phonon Transport ◽  
Epoxy Composites ◽  
Hybrid Fillers ◽  
Interfacial Contact ◽  
The Impact

One-dimensional silver nanowires (AgNWs) and two-dimensional graphene oxide (GO) were combined to construct a three-dimensional network structure. The AgNWs can effectively inhibit stacking of adjacent GO sheets by occupying regions between layers of GO. Moreover, the GO sheets embedded in the gaps of the AgNWs network increase the interfacial contact area between the AgNWs and the epoxy matrix, resulting in the formation of more efficient phonon transport channels. To prepare an epoxy-based thermal conductive composite, hybrid networks were fabricated and added to epoxy resin using a solution mixing method. Significant synergistic effects were observed between the AgNWs and GO sheets. The thermal conductivity of epoxy composites filled with 10 wt.% AgNW/GO hybrids was found to be 1.2 W/mK and the impact strength was 28.85 KJ/m2, which are higher than the corresponding values of composites containing AgNWs or GO sheets alone. Thus, the thermal conductivity and impact strength of the epoxy composites were improved. The additive effects are mainly owing to the improved interfacial contact between the hybrid fillers and the epoxy resin, resulting in a more efficient phonon transport network. The use of hybrid fillers with different structures is a simple and scalable strategy for manufacturing high-performance thermally conductive materials for electronic packaging.

Preparation and properties of novel sulfonic graphene oxide–epoxy resin nanocomposites by resin transfer molding process

2016 ◽  
Vol 51 (9) ◽  
pp. 1197-1208 ◽  
Author(s):  
Wei Li ◽  
Hongyu Li ◽  
Xinguo Yang ◽  
Wei Feng ◽  
Hongyun Huang
Keyword(s):  
Graphene Oxide ◽  
Impact Strength ◽  
Epoxy Resin ◽  
Curing Temperature ◽  
Flexural Property ◽  
Oxide Content ◽  
Molding Process ◽  
One Pot ◽  
Epoxy Resin Nanocomposites ◽  
The Impact

This paper reported a facile one-pot strategy for fabrication of sulfonic graphene oxide–epoxy resin nanocomposites. The rheological and thermal properties were employed to characterize the viscosity and the curing temperature of epoxy resin. Fourier transform infrared spectra for sulfonic graphene oxide and nanocomposites indicated that the sulfonic graphene oxide contains chemical cross-linking responsible for better interactions with the epoxy resin. The state of dispersion was evaluated at different scales by still picture camera and scanning electron microscopy (SEM). Tensile property tests indicated that the tensile strength and elasticity modulus of sulfonic graphene oxide–epoxy resin nanocomposites decreased slowly with increasing of sulfonic graphene oxide content. The critical flexural property and impact strength of epoxy resin filled with sulfonic graphene oxide nanocomposites were measured. The content, size, and dispersion state of sulfonic graphene oxide were examined. It was found that the content of sulfonic graphene oxide has greater impact on both flexural property and impact strength of nanocomposites compared with other conditions. For instance, the impact strength increased by 113.0% and the flexural strength and modulus increased by 39.3% and 55.7% using 1 wt.% sulfonic graphene oxide as compared to neat epoxy resin.

scholarly journals Reduced density spheroplastic based on hollow phenol-formaldehyde microspheres and epoxy resin

2019 ◽  
Vol 58 (4) ◽  
pp. 98-101
Author(s):  
Vladimir Yu. Chukhlanov ◽  
◽  
Kirill V. Smirnov ◽  
Natalia V. Chukhlanova ◽  
◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Impact Strength ◽  
Epoxy Resin ◽  
Phenol Formaldehyde ◽  
Charpy Impact ◽  
Epoxy Oligomer ◽  
Hollow Microspheres ◽  
Stationary Mode ◽  
Gel Formation ◽  
The Impact

In this article the physical-mechanical, thermal and electrical properties of spheroplastic based on epoxy resin ED-20 and hollow phenol-formaldehyde microspheres were studied. The samples were obtained by mixing an epoxy resin, cured with polyethylene polyamine, with hollow phenol-formaldehyde microspheres, poured into a mold and then cured at room temperature. The influence of the filler on the kinetics of the interaction of epoxy oligomer and aliphatic polyamine was studied. The effect of reducing the time of gel formation may occur due to the possible presence of reactive groups on the surface of microspheres. The experiments showed that the introduction of hollow phenol-formaldehyde microspheres in General leads to a slight decrease in the gel formation time. It is established that the introduction of hollow microspheres into the composition leads to a decrease in the density of the finished composition. The impact strength of spheroplastic was determined in accordance with GOST 4647-2015 "Method of Charpy impact strength determination" (ISO 179-1: 2010, NEQ). The introduction of hollow microspheres into the composition leads to a change in the impact strength of the composition in the direction of its decrease. A similar trend is observed in the study of the strength in the separation from the substrate of different materials. The coefficient of thermal conductivity was determined in a stationary mode on the device ITP-MG4"100" GOST 7076-99 "Method for determining the thermal conductivity and thermal resistance in a stationary thermal regime." Studies have shown that an increase in the content of hollow microspheres in the composition to 15% leads to a gradual decrease in the thermal conductivity coefficient to 0.74 W/m∙K. The studied materials can be used as thermal insulation materials and for the manufacture of products used in various fields of science and technology.

scholarly journals Epoxy composites with increased operational characteristics, filled with dispersed mineral fillers

2018 ◽  
Vol 80 (3) ◽  
pp. 330-335
Author(s):  
A. S. Mostovoi ◽  
A. S. Nurtazina ◽  
Yu. A. Kadykova
Keyword(s):  
Impact Strength ◽  
Heat Resistance ◽  
Epoxy Resin ◽  
Oxygen Index ◽  
Epoxy Composite ◽  
Tensile Modulus ◽  
Epoxy Composites ◽  
Breaking Stress ◽  
Mineral Fillers ◽  
The Impact

The aim of this work is to increase the physicochemical, deformation and strength properties and to reduce the combustibility of composites on the base of epoxy resin by introducing a oligo(resorcinophenyl phosphate) with terminal phenyl groups Fyrolflex - modifier of polyfunctional action, and disperse mineral fillers – diorite and chromite. Result of the studies established that the optimum amount of modifier in the composition of the epoxy resin is 40 mass parts, which provides an increase in the operational properties of the composites: the breaking stress at bending increases by 2 times, the breaking stress at compression increases by 28%, the impact strength increases twice, while the modulus of elasticity and hardness of composites slightly decrease. The addition of modifier into the epoxy polymer provides an increase in heat resistance from 86 to 132–156 °C, also it improves the thermal stability of the composite, which manifests itself in a shift from the initial temperature to higher temperatures (from 200 to 230 °C), while it is noticed furthermore that yield of carbonized Structures was risen from 40 to 54%, providing less release of volatile pyrolysis products into the gas phase, which leads to the decrease in flammability of the epoxy composite and it can be shown in the reduction of its loss in mass while cauterizing in air from 78 to about 4.7% and an increase in the oxygen index from 19 to 28% by volume what transfers the material into class with low flammability. The rational content of diorite and chromite (100 parts by weight of chromite and 50 parts by mass of diorite) is chosen as a filler, which ensures an increase in physical and mechanical characteristics and a reduction in the cost of production: the breaking stress increases by 15–30% and the elastic modulus at bending increases 3.5–4.5 times, the breaking stress increases by 35%, and the tensile modulus by 50–240%, the hardness increases by 68–95%, while the impact strength remains at the level of the unfilled plasticized composite. In addition, it is proved that the addition of both diorite and chromite provides an increase in the thermal and heat resistance of epoxy composites, also lowers combustibility of the epoxy composite: the weight loss at ignition in air is reduced to 1.2–2.2% and the oxygen index rises from 28 to 30–35% by volume, thus the material does not support combustion in air and belongs to the class of hardly flammable. The study was carried out with the financial support of a grant for young scientists of the SSTU named after Gagarin Yu.A. (project SGTU-287).

Effects of Weave Type and Fiber Content on Physical Properties of Sisal Fiber/Epoxy Composites

2010 ◽  
Vol 123-125 ◽  
pp. 1139-1142 ◽  
Author(s):  
Sawitri Srisuwan ◽  
Pranee Chumsamrong
Keyword(s):  
Impact Strength ◽  
Physical Properties ◽  
Epoxy Resin ◽  
Flexural Modulus ◽  
Fiber Content ◽  
Epoxy Composites ◽  
Sisal Fiber ◽  
Pure Epoxy ◽  
Sisal Fibers ◽  
The Impact

In this study, the effects of weave type and fiber content on the physical properties of woven sisal fiber/epoxy composites were investigated. Sisal fibers used in this work were obtained from Nakhon Ratchasima, Thailand. Both untreated and alkali-treated fibers were employed. The woven sisal fibers were manufactured by hand weaving process. The fiber content in sisal fiber/epoxy composites were 3 wt.%, 5 wt.% and 10 wt.%. The composites were cured at room temperatures. In order to determine mechanical properties of the composites, flexural and impact tests were applied. Flexural strength and flexural modulus of all composites were higher than those of pure epoxy resin and tended to increase with increasing fiber content. The impact strength of all composites was lower than that of pure epoxy resin. The composites containing 10 wt.% sisal fibers showed the highest impact strength. There was no definite influence of weave type on flexural properties of the composites. At 3 and 5 wt.% fiber, the composites containing plain weave fibers seemed to show a higher impact strength than the composites containing other weave types.

scholarly journals Nanoarchitectonics of BN/AgNWs/Epoxy Composites with High Thermal Conductivity and Electrical Insulation

Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4417
Author(s):  
Xue Li ◽  
Ling Weng ◽  
Hebing Wang ◽  
Xiaoming Wang
Keyword(s):  
Thermal Conductivity ◽  
Epoxy Resin ◽  
Silane Coupling Agent ◽  
Hexagonal Boron Nitride ◽  
Silver Nanowires ◽  
Electrical Insulation ◽  
Epoxy Composites ◽  
Thermal Network ◽  
Silane Coupling ◽  
Dopamine Hydrochloride

To promote the construction of the thermal network in the epoxy resin (EP), a certain proportion of silver nanowires (AgNWs) coupled with the hexagonal boron nitride (BN) nanoplates were chosen as fillers to improve the thermal conductivity of EP resin. Before preparing the composites, BN was treated by silane coupling agent 3-aminopropyltriethoxysilane (KH550), and AgNWs was coated by dopamine hydrochloride. The BN/AgNWs/EP composites were prepared after curing, and the thermal conductivity and dielectric properties of the composites was tested. Results showed that the AgNWs and BN were uniformly dispersed in epoxy resin. It synergistically built a thermal network and greatly increased the thermal conductivity of the composites, which increased 9% after adding AgNWs. Moreover, the electrical property test showed that the addition of AgNWs had little effect on the dielectric constant and dielectric loss of the composites, indicating a rather good electrical insulation of the composites.

scholarly journals Mechanical Properties of Bio-Composites Based on Epoxy Resin and Nanocellulose Fibres

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3576
Author(s):  
Martyna Roszowska-Jarosz ◽  
Joanna Masiewicz ◽  
Marcin Kostrzewa ◽  
Wojciech Kucharczyk ◽  
Wojciech Żurowski ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Impact Strength ◽  
Epoxy Resin ◽  
Raw Materials ◽  
Critical Stress Intensity Factor ◽  
Epoxy Composites ◽  
Chemical Extraction ◽  
Cellulose Pulp ◽  
The Impact ◽  
Unmodified Epoxy

The aim of our research was to investigate the effect of a small nanocellulose (NC) addition on an improvement of the mechanical properties of epoxy composites. A procedure of chemical extraction from pressed lignin was used to obtain nanocellulose fibers. The presence of nanoparticles in the cellulose pulp was confirmed by FTIR/ATR spectra as well as measurement of nanocellulose particle size using a Zetasizer analyzer. Epoxy composites with NC contents from 0.5% to 1.5% w/w were prepared. The obtained composites were subjected to strength tests, such as impact strength (IS) and resistance to three-point bending with a determination of critical stress intensity factor (Kc). The impact strength of nanocellulose composites doubled in comparison to the unmodified epoxy resin (EP 0). Moreover, Kc was increased by approximately 50% and 70% for the 1.5 and 0.5% w/w NC, respectively. The maximum value of stress at break was achieved at 1% NC concentration in EP and it was 15% higher than that for unmodified epoxy resin. The highest value of destruction energy was characterized by the composition with 0.5% NC and corresponds to the increase of 102% in comparison with EP 0. Based on the analysis of the results it was noted that satisfactory improvement of the mechanical properties of the composite was achieved with a very small addition of nanofiller while other research indicates the need to add much more nanocellulose. It is also expected that this kind of use of raw materials will allow increasing the economic efficiency of the nanocomposite preparation process. Moreover, nanocomposites obtained in this way can be applied as elements of machines or as a modified epoxy matrix for sandwich composites, enabling production of the structure material with reduced weight but improved mechanical properties.

scholarly journals Effect of sulfuric acid solution on thermal conductivity and impact strength of epoxy resin reinforced by silicon dioxide powder

2019 ◽  
Vol 17 (41) ◽  
pp. 82-90
Author(s):  
Baraa Khalil Ibrahim
Keyword(s):  
Thermal Conductivity ◽  
Sulfuric Acid ◽  
Impact Strength ◽  
Epoxy Resin ◽  
Weight Ratio ◽  
Chemical Solution ◽  
Dioxide Powder ◽  
Before And After ◽  
Percentage Weight ◽  
The Impact

In this search, Ep/SiO2 at (3, 6, 9, 12 %) composites is prepared by hand Lay-up method, to measure the change in the thermal conductivity and Impact Strength of epoxy resin before and after immersion in H2SO4 Solution with a 0.3N for 10 days. The results before immersion decreases with the increase of the weight ratios of the reinforcement material (SiO2), It changed from (82.6×10-2 to 38.7×10-2 W/m.°C) with change weight ratios from (3 to 12) % respectively, but after immersion time in the chemical solution where it was (65.6×10-2 W/m.°C) at the weight ratios (6 %) and became (46.6 × 10-2 W/m.°C) after immersion in sulfuric acid. The results of the Impact strength decreased by increasing the percentage weight ratio, it changed from (1.48 to 0.87 kJ/m2) with change weight ratios from (3 to 12) % respectively, but found an increase in the value of Impact Strength after immersion in the chemical solution Where it was (1.28 kJ/m2) at the weight ratio of 6 % and became (1.82 kJ/m2) at the same weight ratio after immersion in sulfuric acid at normality of 0.3 for 10 days.

scholarly journals A study of the effect of nano materials on the physical properties of epoxy composites

2019 ◽  
Vol 15 (32) ◽  
pp. 68-76
Author(s):  
Teba Mageed Hameed
Keyword(s):  
Thermal Conductivity ◽  
Grain Size ◽  
Impact Strength ◽  
Physical Properties ◽  
Epoxy Resin ◽  
Epoxy Composites ◽  
Nano Materials ◽  
Rubber Hand ◽  
Coefficient Of Thermal Conductivity ◽  
Research Studies

This research studies the effect of addition of some nanoparticles(MgO, CuO) and grain size (30,40nm) on some physical properties(impact strength, hardness and thermal conductivity) for a matrixblend of epoxy resin with SBR rubber. Hand –Lay up method wasused to prepare the samples. All samples were immersed in water for9 weeks.The Results showed decreased in the values of impact strength andhardness but increased the coefficient of thermal conductivity.

Sign in / Sign up

Export Citation Format

Share Document