The Development of Nanoalumina-Based Cement Mortars for Overlay Applications in Concrete Floors

This article focuses on the development of nanoalumina-based cement mortars for overlay applications in concrete floors. It focuses on the effect of applying aluminum oxide (Al2O3) nanopowder to the cement mortar used to make the overlay, on the adhesion of this overlay to concrete substrate and on its functional properties. It was claimed that the addition of 0.5% of Al2O3 nanopowder has a positive effect on the adhesion of the cement mortar used to make the overlay to the substrate made of concrete. The prior studies performed using scanning electron microscopy (SEM) confirmed that the reason for the improvement in adhesion is the fact that cement mortar used to make the overlay with the addition of 0.5% of Al2O3 nanopowder is less porous than the reference mortar within the interphase. The article concurs that the most favorable results, in terms of lower abrasion resistance and higher subsurface tensile strength of the cement mortar used to make the overlay, are mainly brought about by adding 0.5% of Al2O3 nanopowder.

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STRUCTURES AND PROPERTIES OF NATURAL RUBBER/ORGANOCLAY NANOCOMPOSITES

Science and Technology Development Journal ◽

10.32508/stdj.v14i1.1858 ◽

2011 ◽

Vol 14 (1) ◽

pp. 30-38

Author(s):

Hien Quang Pham ◽

Son Thanh Thanh Do ◽

Nieu Huu Nguyen

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Tensile Strength ◽

Natural Rubber ◽

Abrasion Resistance ◽

X Ray Diffraction ◽

X Ray ◽

Structures And Properties ◽

Scanning Electron

Natural rubber (NR), 30% epoxidized natural rubber (ENR30) and organoclays (Nanomer I28E and I30E) are blended in Brabender. Dispersions of the organoclay in NR are investigated by X – ray diffraction (XRD) and scanning electron microscopy (SEM). The results revealed the increase of dispersion efficiency by the addition of ENR30 as a compatibilizer. The existence of organoclay I28E reduces the vulcanization time, while torque value increases slightly and mechanical properties (abrasion resistance, modulus M100, modulus M300, tensile strength, tear strength) are improved considerably.

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Analysis of PLA Composite Filaments Reinforced with Lignin and Polymerised-Lignin-Treated NFC

Polymers ◽

10.3390/polym13132174 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2174

Author(s):

Diana Gregor-Svetec ◽

Mirjam Leskovšek ◽

Blaž Leskovar ◽

Urška Stanković Elesini ◽

Urška Vrabič-Brodnjak

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Tensile Strength ◽

Glassy State ◽

Nanofibrillated Cellulose ◽

Dynamic Mechanical Properties ◽

Initial Modulus ◽

Surface Modified ◽

Scanning Electron

Polylactic acid (PLA) is one of the most suitable materials for 3D printing. Blending with nanoparticles improves some of its properties, broadening its application possibilities. The article presents a study of composite PLA matrix filaments with added unmodified and lignin/polymerised lignin surface-modified nanofibrillated cellulose (NFC). The influence of untreated and surface-modified NFC on morphological, mechanical, technological, infrared spectroscopic, and dynamic mechanical properties was evaluated for different groups of samples. As determined by the stereo and scanning electron microscopy, the unmodified and surface-modified NFCs with lignin and polymerised lignin were present in the form of plate-shaped agglomerates. The addition of NFC slightly reduced the filaments’ tensile strength, stretchability, and ability to absorb energy, while in contrast, the initial modulus slightly improved. By adding NFC to the PLA matrix, the bending storage modulus (E’) decreased slightly at lower temperatures, especially in the PLA samples with 3 wt% and 5 wt% NFC. When NFC was modified with lignin and polymerised lignin, an increase in E’ was noticed, especially in the glassy state.

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Effect of Annealing Process on the Mechanical Properties of X70 Pipeline Steel

MATEC Web of Conferences ◽

10.1051/matecconf/201818602001 ◽

2018 ◽

Vol 186 ◽

pp. 02001

Author(s):

Teng-wei Zhu ◽

Cheng-liang Miao ◽

Zheng Cheng ◽

Zhipeng Wang ◽

Yang Cui ◽

...

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Tensile Strength ◽

Annealing Temperature ◽

Pipeline Steel ◽

Annealing Process ◽

X70 Pipeline Steel ◽

Grain Sizes ◽

Scanning Electron

The influence of the mechanical properties of X70 pipeline steel under different annealing temperature was studied. The corresponding microstructure was investigated by the Field Emission Scanning Electron Microscopy. The results showed that the yield strength and the tensile strength both experienced from rise to decline with the increase of annealing temperature. The grain sizes were coarse and a large amount of cementite precipitated due to preserving temperature above 550 °, which induced matrix fragmentation and deteriorate the -10 ° DWTT Toughness. There were little changes on the microstructure and mechanical properties when the annealing temperature was under 500 °.

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Tensile Property of the Flax/Polyester Composites after Water Treatment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.194-196.1740 ◽

2011 ◽

Vol 194-196 ◽

pp. 1740-1744 ◽

Cited By ~ 1

Author(s):

Qiu Hong Wang ◽

Gu Huang

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Tensile Strength ◽

Water Treatment ◽

Tensile Property ◽

Unsaturated Polyester ◽

Water Immersion ◽

The Matrix ◽

Polyester Composites ◽

Scanning Electron

Flax fabric was woven and composites were produced by using the VARI technique with flax fabric as the reinforcement and unsaturated polyester as the matrix. Laminates with two, three and four layers were fabricated respectively. After saturated in the water for different durations of time (7, 14, 21 and 30 days), the tensile strength of the composites was tested. After being soaked in the water for 7, 14 and 21 days, the tensile strength of the two-layer composites was decreased. For the three and four layers specimens, the tensile strength was increased initially with water treatment for 7 and 14 days,and decreased for 21 and 30 days. Scanning electron microscopy (SEM) confirmed that it might be contributed to the thickness of the two-layer composites. The thinner specimen is easier to be damaged by the penetrated moisture owing to the delamination between the fiber and the matrix after water immersion. For the three and four layers specimens, their contradictory tensile strength suggests that the thicker specimen can delay the moisture permeation and is of better water durability.

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Tensile and flammability characterizations of corn straw slagging/high-density polyethylene composites

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705719830459 ◽

2019 ◽

Vol 33 (11) ◽

pp. 1466-1477

Author(s):

Qingfa Zhang ◽

Wenyu Lu ◽

Liang Zhou ◽

Donghong Zhang ◽

Hongzhen Cai ◽

...

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Tensile Strength ◽

Flame Retardant ◽

High Density Polyethylene ◽

Oxygen Index ◽

High Density ◽

Corn Straw ◽

Scanning Calorimetry ◽

Scanning Electron

Biocomposites were prepared with corn straw slagging (CSS) and high-density polyethylene (HDPE) at four loading levels (10, 20, 30, and 40 wt%) by extrusion method. CSS/HDPE composites were tested by tension, oxygen index meter, differential scanning calorimetry, X-ray diffraction, and the scanning electron microscopy. The scanning electron microscopy showed that CSS was dispersed uniformly in the HDPE matrix and strong interfacial interaction was achieved, which had an important influence on the tensile strength of the composites. The tensile strength of the composites could be improved with proper increase of CSS and reached maximum value at 30 wt% content. Furthermore, the addition of CSS played an important role in improving the flame-retardant ability of CSS/HDPE composites, and the limited oxygen index was 31.26% at 40 wt% content, good flame-retardant effect achieved.

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Toughened Chitosan Composite Nanofiltration Membrane by Introduction of Acrylic Acid

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.815.139 ◽

2019 ◽

Vol 815 ◽

pp. 139-144

Author(s):

Tao Mu

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Tensile Strength ◽

Acrylic Acid ◽

Nanofiltration Membrane ◽

Modified Chitosan ◽

Atomic Force ◽

Infrared Spectrophotometer ◽

Chitosan Composite ◽

Scanning Electron

In this paper, acrylic acid was grafted to chitosan in order to change the structure; polymer was obtained from modified chitosan. A series of novel toughened composite NF memebranes were prepared by over-coating the polysulfone ultrafiltration membrane with the polymer of modified chitosan. The chitosan derivatives and the polymer were characterised by infrared spectrophotometer (IR); the structure of the membrane was characrerised by scanning electron microscopy (SEM) and atomic force microscope (AFM). The composite NF membrane’s performances were strictly related to the structure of polymer. The rejection of the membrane was 96.3% with flux as high as 386.46 L m-2 h-1 with the 1000 mg/L of NaCl. Tensile strength of membrane increased 46%. The HCl (5%) resistance increased from 20.3 to 36.8h. The NaOH (5%) resistance increased from 18.3 to 31.6h. These results indicated the prepared toughened composite NF memebrane was excellent NF membrane, which had a wide application prospect.

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Development of Alginate Based Active Films Containing Turmeric Essential Oil

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.861.378 ◽

2020 ◽

Vol 861 ◽

pp. 378-382

Author(s):

Sophoan Phal ◽

Muhammad Rafiullah Khan ◽

Pattarin Leelaphiwat ◽

Vanee Chonhenchob

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Tensile Strength ◽

Water Vapor ◽

Essential Oil ◽

Sem Analysis ◽

Film Properties ◽

Elongation At Break ◽

Control Film ◽

Scanning Electron

Sodium alginate based films containing turmeric oil (TEO) at different concentrations (1, 2 and 3%) were developed. The film with no TEO was used as control. Incorporation of TEO had the effects on the film properties. With increasing TEO concentrations, thickness, elongation at break, permeability of oxygen and water vapor of the films significantly (p ≤ 0.05) increased. Whereas moisture content, tensile strength and modulus of elasticity significantly (p ≤ 0.05) decreased. Scanning electron microscopy (SEM) analysis showed more numerous pores and rougher surface of the antifungal films than the control film.

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