The control mechanism of micron and nano SiO2/epoxy composite coating on surface charge in epoxy resin

To study the effect of hyperbranched polyester with different kinds of terminal groups on the thermomechanical and dielectric properties of silica–epoxy resin composite, a molecular dynamics simulation method was utilized. Pure epoxy resin and four groups of silica–epoxy resin composites were established, where the silica surface was hydrogenated, grafted with silane coupling agents, and grafted with hyperbranched polyester with terminal carboxyl and terminal hydroxyl, respectively. Then the thermal conductivity, glass transition temperature, elastic modulus, dielectric constant, free volume fraction, mean square displacement, hydrogen bonds, and binding energy of the five models were calculated. The results showed that the hyperbranched polyester significantly improved the thermomechanical and dielectric properties of the silica–epoxy composites compared with other surface treatments, and the terminal groups had an obvious effect on the enhancement effect. Among them, epoxy composite modified by the hyperbranched polyester with terminal carboxy exhibited the best thermomechanical properties and lowest dielectric constant. Our analysis of the microstructure found that the two systems grafted with hyperbranched polyester had a smaller free volume fraction (FFV) and mean square displacement (MSD), and the larger number of hydrogen bonds and greater binding energy, indicating that weaker strength of molecular segments motion and stronger interfacial bonding between silica and epoxy resin matrix were the reasons for the enhancement of the thermomechanical and dielectric properties.

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Time-Temperature Dependences of Fracture Toughnesses of Epoxy Resin and Silica Particulate-Filled Epoxy Composite

Materials Science Forum ◽

10.4028/www.scientific.net/msf.426-432.1985 ◽

2003 ◽

Vol 426-432 ◽

pp. 1985-1990 ◽

Cited By ~ 7

Author(s):

Wakako Araki ◽

Tadaharu Adachi ◽

Akihiko Yamaji

Keyword(s):

Epoxy Resin ◽

Epoxy Composite ◽

Temperature Dependences

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Studies on Thermal Property of Silica Aerogel/Epoxy Composite

Materials Science Forum ◽

10.4028/www.scientific.net/msf.546-549.1581 ◽

2007 ◽

Vol 546-549 ◽

pp. 1581-1584 ◽

Cited By ~ 14

Author(s):

Jiu Peng Zhao ◽

Deng Teng Ge ◽

Sai Lei Zhang ◽

Xi Long Wei

Keyword(s):

Thermal Conductivity ◽

Thermal Property ◽

Epoxy Resin ◽

Silica Aerogel ◽

Epoxy Composite ◽

Transfer Model ◽

Insulation Material ◽

Thermal Transfer ◽

Heat Distortion Temperature ◽

Ft Ir

Silica aerogel/epoxy composite, a kind of efficient thermal insulation material, was prepared by doping silica aerogel of different sizes into epoxy resin through thermocuring process. The results of thermal experiments showed that silica aerogel/epoxy composite had a lower thermal conductivity (0.105W/(m·k) at 60 wt% silica aerogel) and higher serviceability temperature (Martens heat distortion temperature: 160°C at 20 wt% silica aerogel). In addition, the composite doping larger size (0.2-2mm) of silica aerogel particle had lower thermal conductivity and higher Martens heat distortion temperature. Based on the results of SEM and FT-IR, the thermal transfer model was established. Thermal transfer mechanism and the reasons of higher Martens heat distortion temperature have been discussed respectively.

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MECHANICAL PROPERTIES OF EPOXY RESIN BASED GRAPHENE NANO PARTICLES COMPOSITE

Journal of Manufacturing Engineering ◽

10.37255/jme.v15i4pp84-92 ◽

2020 ◽

Vol 15 (4) ◽

Author(s):

Durgaprasad Kollipara ◽

Prabhakar Gope VNB ◽

Raja Loya

Keyword(s):

Mechanical Properties ◽

Epoxy Resin ◽

Epoxy Composite ◽

Hardness Test ◽

Industrial Applications ◽

Mechanical Tests ◽

Nano Particles ◽

Potential Candidate ◽

Matrix Composites ◽

Reinforcing Material

Composites have tremendous applicability due to their excellent capabilities. The performance of composites mainly depends on the reinforcing material applied. A Graphene nanoparticle (GNP) is successful as an efficient reinforcing material due to its versatile as well as superior properties. Even at very low content, graphene can dramatically improve the properties of polymer and metal matrix composites. In this paper the effects of GNP on composites based on epoxy resin were analyzed. Different contents of GNP (0 – 4.5 vol. %) were added to the epoxy resin. The GNP/epoxy composite was fabricated under room temperature. Mechanical tests result such as tensile, flexural and hardness test show enhancements of the mechanical properties of the GNP/epoxy composite. The experimental results clearly show an improvement in Young’s modulus, tensile strength, and hardness as compared to pure epoxy. The results of this research are strong evidence for GNP/epoxy composites being a potential candidate for use in a variety of industrial applications, especially for automobile parts, aircraft components, and electronic parts such as super capacitors, transistors, etc.

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Influence of Polyurea Composite Coating on Selected Mechanical Properties of AISI 304 Steel

Materials ◽

10.3390/ma12193137 ◽

2019 ◽

Vol 12 (19) ◽

pp. 3137 ◽

Cited By ~ 3

Author(s):

Monika Duda ◽

Joanna Pach ◽

Grzegorz Lesiuk

Keyword(s):

Mechanical Properties ◽

Epoxy Resin ◽

Composite Coating ◽

Composite Coatings ◽

Glass Fabric ◽

Coated Sample ◽

Hemp Fiber ◽

Aisi 304 ◽

Aisi 304 Steel ◽

The Impact

This paper contains experimental results of mechanical testing of the AISI 304 steel with composite coatings. The main goal was to investigate the impact of the applied polyurea composite coating on selected mechanical properties: Adhesion, impact resistance, static behavior, and, finally, fatigue lifetime of notched specimens. In the paper the following configurations of coatings were tested: EP (epoxy resin), EP_GF (epoxy resin + glass fabric), EP_GF_HF (epoxy resin + glass fabric hemp fiber), EP_PUA (epoxy resin + polyurea) resin, EP_GF_PUA (epoxy resin + glass fabric + polyurea) resin, and EP_GF_HF_PUA (epoxy resin + glass fabric + hemp fiber + polyurea) resin. The highest value of force required to break adhesive bonds was observed for the EP_PUA coating, the smallest for the single EP coating. A tendency of polyurea to increase the adhesion of the coating to the base was noticed. The largest area of delamination during the impact test was observed for the EP_GF_HF coating and the smallest for the EP-coated sample. In all tested samples, observed delamination damage during the pull-off test was located between the coating and the metallic base of the sample.

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Influence of nano-SiO2 on the bonding strength and wear resistance properties of polyurethane coating

Science and Engineering of Composite Materials ◽

10.1515/secm-2018-0078 ◽

2019 ◽

Vol 26 (1) ◽

pp. 77-83 ◽

Cited By ~ 1

Author(s):

Fangfang Wang ◽

Lajun Feng ◽

Huini Ma ◽

Zhe Zhai ◽

Zheng Liu

Keyword(s):

Wear Resistance ◽

Friction Coefficient ◽

Wear Rate ◽

Composite Coating ◽

Network Structure ◽

Bonding Strength ◽

Coating Layer ◽

Steel Substrate ◽

Polyurethane Coating ◽

Nano Sio2

Abstract To improve the wear resistance of polyurethane (PU) coating and its adhesion to the steel substrate, a series of simple and practicable techniques were designed to mix nano-SiO2 with PU powder to cast a coating layer onto the steel. When the addition of nano-SiO2 was small, a network structure of PU-SiO2 was produced. It improved the wear resistance of the composite coating and its adhesion to the steel substrate. When the addition of nano-SiO2 was excessive, agglomerated nano-SiO2 particles not only affected the bond between the PU resin and the steel substrate but also became abrasive materials, intensifying the abrasion of the composite coating during friction. It resulted in lower bonding strength and poorer wear resistance of the composite coating. The wear rate and friction coefficient of 2 wt.% SiO2/PU composite coating were 1.52×10−6 cm3/min N and 0.31, respectively. Its wear resistance was about 10 times as high as that of the pure PU coating. Furthermore, a simple and practicable installation was designed to test the bonding strength between the coating and the steel substrate. The bonding strength between 2 wt.% SiO2/PU composite coating and the steel substrate was 7.33 MPa, which was 39% higher than that of the pure PU coating.

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