Internal matrix structure of low-κ mesoporous silica and its relation to mechanical properties

Natural rubber (NR) is one of the most important agriculture products of Thailand, which is an important material with unique and special characteristics used in wide range of applications such as mechanical properties, excellent strength, and elasticity. However, it is inferior in oil resistance due to the presence of hydrogen and carbon in its structure. This inherent drawback of NR has limited its application in industry. In order to expand the use of NR, this research is interested to improve the oil resistance of NR without loss of outstanding properties by grafting NR with acrylonitrile (AN) monomer to form the nano-matrix structure. The influences of the initial monomer concentration and initial initiator concentration were investigated. These effects on structure, mechanical properties and oil resistance properties were studied by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy, tensile machine, and swelling in toluene, respectively. It was found that the tensile strength and oil resistance properties of graft copolymerization of AN onto NR increased with increasing the percentage grafting efficiency of acrylonitrile monomer.

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Comparison of Shear, Compressive and Tensile Characteristics of Cast Irons

Journal of Mechanical Engineering Science ◽

10.1243/jmes_jour_1973_015_009_02 ◽

1973 ◽

Vol 15 (1) ◽

pp. 53-60 ◽

Cited By ~ 1

Author(s):

R. D. Adams ◽

M. A. O. Fox

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Design Criteria ◽

Matrix Structure ◽

Proof Stress ◽

Cast Irons ◽

The Matrix ◽

The Relationship ◽

Graphite Inclusions ◽

Strength And Ductility

Cast irons were produced with variations in the quantity and shape of the free graphite inclusions and in the matrix structure to investigate the relationship between the shear, compressive and tensile mechanical properties. Differences were observed which may have a significant effect on design criteria for cast irons. For example, the ratio of shear to tensile strengths decreased from about 1·25 to 0·577 and the ratio of 0·1 per cent proof stress in compression to that in tension decreased from approximately 2 to 11 as the tensile strength (and ductility) were increased.

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Biomimetic Hemocompatible Nanofibrous Scaffolds as Potential Small-Diameter Blood Vessels by Bilayering Electrospun Technique

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.306-307.1627 ◽

2011 ◽

Vol 306-307 ◽

pp. 1627-1630 ◽

Cited By ~ 2

Author(s):

He Yun Wang ◽

Ya Kai Feng ◽

Hai Yang Zhao ◽

Ruo Fang Xiao ◽

Jin Tang Guo

Keyword(s):

Mechanical Properties ◽

Blood Vessel ◽

Breaking Strength ◽

Small Diameter ◽

Matrix Structure ◽

Complex Matrix ◽

Elongation At Break ◽

Artificial Blood ◽

Nanofibrous Scaffolds ◽

Morphology And Mechanical Properties

In this paper, we prepared a scaffold composed of a polyurethane (PU) fibrous outside-layer and a gelatin-heparin fibrous inner-layer with mimicking morphology and mechanical properties of a native blood vessel by sequential bilayering electrospinning technology on a rotating mandrel-type collector. The scaffolds achieved the appropriate breaking strength (3.7 ± 0.13 MPa) and elongation at break (110 ± 8%). When the scaffolds were immersed in water for 1 h, the breaking strength decreased slightly to 2.2 ± 0.3 MPa, but the elongation at break increased up to 145 ± 21%. Heparin was released from the scaffolds at substantially uniform rate until the 9th day. The scaffolds were expected to mimic the complex matrix structure of native arteries, and had good hemocompatibility as an artificial blood vessel owing to the heparin release.

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Rheological and Thermomechanical Properties of Meso and Non-Porous Silica Filled Epoxy Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.815.67 ◽

2015 ◽

Vol 815 ◽

pp. 67-71

Author(s):

Gang Li ◽

Peng Li Zhu ◽

Tao Zhao ◽

Rong Sun ◽

Daniel Lu

Keyword(s):

Mechanical Properties ◽

Thermal Expansion ◽

Glass Transition ◽

Mesoporous Silica ◽

Coefficient Of Thermal Expansion ◽

Porous Silica ◽

Thermomechanical Properties ◽

Epoxy Composites ◽

Silica Microspheres ◽

Silica Filler

In the present study, epoxy based composite filled with meso and non-porous silica microspheres with similar size were prepared respectively and their rheological and thermo-mechanical properties were studied systematically. The results showed that the mesoporous silica/epoxy composites showed much higher viscosity, storage modulus and glass transition temperature (Tg) while lower coefficient of thermal expansion (CTE) than did epoxy composites with nonporous silica particles, which could be attributed to the stronger interface interaction between the mesoporous silica filler with larger specific surface area (BET) and the epoxy matrix.

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The improvement of mechanical properties of conventional concretes using carbon nanoparticles using molecular dynamics simulation

Scientific Reports ◽

10.1038/s41598-021-99616-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Liang Zhao ◽

Mahyuddin K. M. Nasution ◽

Maboud Hekmatifar ◽

Roozbeh Sabetvand ◽

Pavel Kamenskov ◽

...

Keyword(s):

Mechanical Properties ◽

Carbon Nanotubes ◽

Molecular Dynamics ◽

Mechanical Behavior ◽

Young’S Modulus ◽

Carbon Nanoparticles ◽

Young's Modulus ◽

Dynamics Simulation ◽

Matrix Structure ◽

Concrete Matrix

AbstractIn the present study, the improvement of mechanical properties of conventional concretes using carbon nanoparticles is investigated. More precisely, carbon nanotubes are added to a pristine concrete matrix, and the mechanical properties of the resulting structure are investigated using the molecular dynamics (MD) method. Some parameters such as the mechanical behavior of the concrete matrix structure, the validation of the computational method, and the mechanical behavior of the concrete matrix structure with carbon nanotube are also examined. Also, physical quantities such as a stress–strain diagram, Poisson's coefficient, Young's modulus, and final strength are calculated and reported for atomic samples under external tension. From a numerical point of view, the quantities of Young's modulus and final strength are converged to 35 GPa and 35.38 MPa after the completion of computer simulations. This indicates the appropriate effect of carbon nanotubes in improving the mechanical behavior of concrete and the efficiency of molecular dynamics method in expressing the mechanical behavior of atomic structures such as concrete, carbon nanotubes and composite structures derived from raw materials is expressed that can be considered in industrial and construction cases.

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