Influence of Hydroxyl Group Concentration on Mechanical Properties and Impact Resistance of ROMP Copolymers

This study investigated the combine effect of 0.2 % drink cans and steel fibers with volume fractions of 0%, 0.5%, 1%, 1.5%, 2%, 2.5% and 3% to the mechanical properties and impact resistance of concrete. Hooked-end steel fiber with 30 mm and 0.75 mm length and diameter, respectively was selected for this study. The drinks cans fiber were twisted manually in order to increase friction between fiber and concrete. The results of the experiment showed that the combination of steel fibers and drink cans fibers improved the strength performance of concrete, especially the compressive strength, flexural strength and indirect tensile strength. The results of the experiment showed that the combination of steel fibers and drink cans fibers improved the compressive strength, flexural strength and indirect tensile strength by 2.3, 7, and 2 times as compare to batch 1, respectively. Moreover, the impact resistance of fiber reinforced concrete has increase by 7 times as compared to non-fiber concretes. Moreover, the impact resistance of fiber reinforced concrete consistently gave better results as compared to non-fiber concretes. The fiber reinforced concrete turned more ductile as the dosage of fibers was increased and ductility started to decrease slightly after optimum fiber dosage was reached. It was found that concrete with combination of 2% steel and 0.2% drink cans fibers showed the highest compressive, split tensile, flexural as well as impact strength.

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Effect of SWCNT-Tuball Paper on the Lightning Strike Protection of CFRPs and Their Selected Mechanical Properties

Materials ◽

10.3390/ma14113140 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3140

Author(s):

Kamil Dydek ◽

Anna Boczkowska ◽

Rafał Kozera ◽

Paweł Durałek ◽

Łukasz Sarniak ◽

...

Keyword(s):

Mechanical Properties ◽

Carbon Nanotubes ◽

Electrical Conductivity ◽

Copper Foil ◽

Impact Resistance ◽

Mechanical Analysis ◽

Lightning Strike ◽

Single Wall Carbon Nanotubes ◽

Carbon Fibre Reinforced Polymer ◽

The Impact

The main aim of this work was the investigation of the possibility of replacing the heavy metallic meshes applied onto the composite structure in airplanes for lightning strike protection with a thin film of Tuball single-wall carbon nanotubes in the form of ultra-light, conductive paper. The Tuball paper studied contained 75 wt% or 90 wt% of carbon nanotubes and was applied on the top of carbon fibre reinforced polymer before fabrication of flat panels. First, the electrical conductivity, impact resistance and thermo-mechanical properties of modified laminates were measured and compared with the reference values. Then, flat panels with selected Tuball paper, expanded copper foil and reference panels were fabricated for lightning strike tests. The effectiveness of lightning strike protection was evaluated by using the ultrasonic phased-array technique. It was found that the introduction of Tuball paper on the laminates surface improved both the surface and the volume electrical conductivity by 8800% and 300%, respectively. The impact resistance was tested in two directions, perpendicular and parallel to the carbon fibres, and the values increased by 9.8% and 44%, respectively. The dynamic thermo-mechanical analysis showed higher stiffness and a slight increase in glass transition temperature of the modified laminates. Ultrasonic investigation after lightning strike tests showed that the effectiveness of Tuball paper is comparable to expanded copper foil.

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Effects of maximum particle size of coarse aggregates and steel fiber contents on the mechanical properties and impact resistance of recycled aggregate concrete

Advances in Structural Engineering ◽

10.1177/13694332211017998 ◽

2021 ◽

pp. 136943322110179

Author(s):

DongTao Xia ◽

ShaoJun Xie ◽

Min Fu ◽

Feng Zhu

Keyword(s):

Mechanical Properties ◽

Particle Size ◽

Steel Fiber ◽

Impact Resistance ◽

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Aggregate Concrete ◽

Coarse Aggregates ◽

Maximum Particle Size ◽

Maximum Particle

Fiber reinforced recycled aggregate concrete has become a new type of green concrete material. The maximum particle size of coarse aggregates and steel fiber contents affect the mechanical properties and impact resistance of recycled aggregate concrete. However, such studies are rare in literature. The present paper shortens the gap through experimental study. A total of 144 specimens of 12 kinds of concrete mixtures were tested, which adopted different steel fiber volume admixtures (0%, 0.8%, 1.0%, 1.2%) and recycled coarse aggregates in different maximum particle sizes (9.5, 19, 31.5 mm) replacing 30% natural coarse aggregate. The compressive strength, splitting tensile strength, and impact resistance of the 12 concrete mixtures were tested. The results showed that the compressive strength, splitting tensile strength, and impact resistance of recycled aggregate concrete increased first and then decreased with the increase of the maximum particle size. The recycled aggregate concrete with the maximum particle size of 19 mm had the highest mechanical properties and impact resistance. Besides, with the increase of steel fiber content, the compressive strength, splitting tensile strength, and impact resistance of recycled aggregate concrete showed an increasing trend. Considering a large amount of experimental data and the coupling effect of steel fiber contents and the maximum particle size of coarse aggregates, the Weibull distribution function was introduced to analyze the impact test results and predict the number of resistance to impact under different failure probabilities. The results showed that the number of blows of the recycled aggregate concrete followed a two-parameter Weibull distribution, and the estimated value of the number of resistance to impact for failure increased with the increase of the failure probability.

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Preparation and Characterization of Sawdust Derived Bio-Fuel Pellets Depending on "Solid Bridge" Intertwining Action of Hyacinth Fiber

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.878.450 ◽

2014 ◽

Vol 878 ◽

pp. 450-458

Author(s):

Ling Jun Kong ◽

Xiong Fei Zhang ◽

Shuang Hong Tian ◽

Ting Liu ◽

Ya Xiong

Keyword(s):

Mechanical Properties ◽

Room Temperature ◽

Elastic Recovery ◽

Impact Resistance ◽

Resistance Index ◽

Cost Effective ◽

Environmental Benefits ◽

Fuel Pellet ◽

Mass Ratio ◽

Solid Bridge

Densified biomass pellets named as H/S-BPs were prepared from waste wood sawdust (S) in the presence of water hyacinth fiber (H) as solid bridge under room temperature and 6 MPa lower than in the previous study. Mechanical properties including relaxed density (ρr), resiliency (R), abrasion resistance (AR) and impact resistance index (IRI) were evaluated. Results showed that adding H greatly reduced negative effect of resiliency on the mechanical properties of H/S-BPs during storage. For example, H/S-BPs compressed at 6 MPa in an H/S mass ratio of 1 to 3 presented lower resiliency of 10% and higher relaxed density of 1.04 kg dm-3 than pellets without H fiber. This is due to the intertwining action of H fiber, what fabricates solid bridge, replacing the bonding creating by applying high pressure to resist the disruptive force caused by elastic recovery. Thus, compression of waste H and S in a mass ratio of 1 to 3 at room temperature under 6 MPa is a cost-effective process to produce densified sustainable bio-fuel pellet as well as dispose waste S and H, combining the economical and environmental benefits.

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Phase Morphology, Thermal and Mechanical Properties of Compatibilized Nylon12/Natural Rubber Blends Using PS/MNR

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.844.53 ◽

2013 ◽

Vol 844 ◽

pp. 53-56

Author(s):

Saravalee Saengthaveep ◽

Sadhan C. Jana ◽

Rathanawan Magaraphan

Keyword(s):

Mechanical Properties ◽

Natural Rubber ◽

Moisture Absorption ◽

Rubber Particle ◽

Impact Resistance ◽

Phase Morphology ◽

Thermal And Mechanical Properties ◽

Binary Blend ◽

Polyamide 12 ◽

The Impact

To produce a tough material for application demanding high impact resistance and low moisture absorption, melt blending of Nylon12 (Polyamide 12, PA12) and natural rubber (NR) was carried out in a brabender plasticorder at 210 °C with rotor speed of 70 rpm in the presence of polystyrene/maleated natural rubber (PS/MNR) blend as a compatibilizer. The effect of compatibilizer content (1, 3, 5, 7 and 10 phr) on phase morphology, thermal, and mechanical properties of [Nylon12/NR]/[PS/MNR] blends was investigated by using SEM, DSC, and Izod impact tester, respectively. The result revealed that PS/MNR blend improved the compatibility of Nylon12/NR blends efficiently due to the presence of amide linkage at the interfaces from the reaction between the reactive groups of MNR and the NH2 end groups of Nylon12 during mixing. A fine phase morphology (good dispersion and small dispersed phase size of NR domains in Nylon12 matrix) of [Nylon12/NR]/[PS/MNR] blends was observed at the optimum compatibilizer content of 7 phr, relating to the improvement of mechanical property. The impact energy of [Nylon12/NR]/[PS/MNR] blends was 503 J/m higher than that of neat Nylon12 (115 J/m) and Nylon12/NR binary blend (241 J/m) due to the toughening effect of rubber and proper morphology. The melting temperature of all blends did not change obviously from thermal analysis. However, the presence of rubber particle obstructed the crystallization of Nylon12 phase, leading to the decreasing of %crystallinity from 93% to around 70%.

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Performance of Wood-Polymer Composite Prepared by In Situ Synthesis of Terpolymer within Wood

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.34-35.1165 ◽

2010 ◽

Vol 34-35 ◽

pp. 1165-1169 ◽

Cited By ~ 1

Author(s):

Yong Feng Li ◽

Bao Gang Wang ◽

Qi Liang Fu ◽

Yi Xing Liu ◽

Xiao Ying Dong

Keyword(s):

Mechanical Properties ◽

Porous Structure ◽

Polymer Composite ◽

Value Added ◽

Untreated Wood ◽

Modulus Of Rupture ◽

Hydroxyl Group ◽

Wood Polymer ◽

Wood Polymer Composite

In order to improve the value-added applications of low-quality wood, a novel composite, wood-polymer composite, was fabricated by in-situ terpolymerization of MMA, VAc and St within wood porous structure. The structure of the composite and the reaction of monomers within wood were both analyzed by SEM and FTIR, and the mechanical properties were also evaluated. The SEM observation showed that the polymer mainly filled up wood pores, suggesting good polymerizating crafts. The FTIR results indicated that under the employed crafts, three monomers terpolymerized in wood porous structure, and grafted onto wood matrix through reaction of ester group from monomers and hydroxyl group from wood components, suggesting chemical combination between the two phases. The mechanical properties of the wood-polymer composite involving modulus of rupture, compressive strength, wearability and hardness were improved 69%, 68%, 36% and 210% over those of untreated wood, respectively. Such method seems to be an effective way to converting low-quality wood to high-quality wood.

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Preparation of Polymer Nanoparticles and Application on Nitrile-Butadiene Rubber Reinforcement

Materials Science Forum ◽

10.4028/www.scientific.net/msf.900.35 ◽

2017 ◽

Vol 900 ◽

pp. 35-39

Author(s):

Cheng Chien Wang ◽

Chih Lung Chiu ◽

Jian Sheng Shen

Keyword(s):

Mechanical Properties ◽

Hydroxyl Group ◽

Molar Ratio ◽

Butadiene Rubber ◽

Microemulsion Polymerization ◽

Rubber Latex ◽

Elongation At Break ◽

Divinyl Benzene ◽

Rubber Nanocomposites ◽

Average Size

The different amount of hydrophilic hydroxyl group, including 3, 5, 7 and 10 wt.% copoly (styrene-co - divinyl benzene – co - 2-hydroxylethylenemethacrylate) (poly (St-co-DVB- co -HEMA) s) nanoparticles were synthesized via microemulsion polymerization in the present paper. The average size of the poly (St-co-DVB-co-HEMA) s was ca. 44 nm after zetasizer (DLS) measurement and SEM observation. The characteristic peaks at 3200 ~3600 cm-1 in FTIR was assigned at hydroxyl group of HEMA unit. The NBR/poly (St-co-DVB-co-HEMA) s composites films with 250 μm thickness were prepared simply via latex mixing and followed by spinning coating. The mechanical properties of the poly (St-co-DVB-co-HEMA) s/rubber nanocomposites, including the tensile strength, modulus and elongation, were increased with that of increasing of poly (St-co-DVB-co-HEMA) s adding. In addition, as the poly (St-co-DVB-co-HEMA) s nanoparticles carried out with constant St/HEMA molar ratio of 97:3 and the DVB content in 10 wt.%, the elongation at break that up to more than 3500% and the ultimate stress increased from 0.2 MPa to 0.6 MPa. The poly (St-co-DVB-co-HEMA) s nanoparticles prepared by emulsion polymerization could be successfully enhanced the mechanical properties of rubber latex.

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A Review on Mechanical Models for Cellular Media: Investigation on Material Characterization and Numerical Simulation

Polymers ◽

10.3390/polym13193283 ◽

2021 ◽

Vol 13 (19) ◽

pp. 3283

Author(s):

Guoqiang Luo ◽

Yuxuan Zhu ◽

Ruizhi Zhang ◽

Peng Cao ◽

Qiwen Liu ◽

...

Keyword(s):

Mechanical Properties ◽

Numerical Simulation ◽

Impact Resistance ◽

Constitutive Models ◽

Economic Loss ◽

Constitutive Relationship ◽

Cell Models ◽

Mechanical Models ◽

Mechanical Properties Characterization ◽

Buffer Structure

Cellular media materials are used for automobiles, aircrafts, energy-efficient buildings, transportation, and other fields due to their light weight, designability, and good impact resistance. To devise a buffer structure reasonably and avoid resource and economic loss, it is necessary to completely comprehend the constitutive relationship of the buffer structure. This paper introduces the progress on research of the mechanical properties characterization, constitutive equations, and numerical simulation of porous structures. Currently, various methods can be used to construct cellular media mechanical models including simplified phenomenological constitutive models, homogenization algorithm models, single cell models, and multi-cell models. This paper reviews current key mechanical models for cellular media, attempting to track their evolution from their inception to their latest development. These models are categorized in terms of their mechanical modeling methods. This paper focuses on the importance of constitutive relationships and microstructure models in studying mechanical properties and optimizing structural design. The key issues concerning this topic and future directions for research are also discussed.

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The effect of curing conditions on the mechanical properties of SIFCON

10.7764/rdlc.20.1.37 ◽

2021 ◽

Vol 20 (1) ◽

pp. 37-51

Author(s):

Kubilay Akçaözoğlu ◽

◽

Adem Kıllı ◽

Keyword(s):

Mechanical Properties ◽

Flexural Strength ◽

Steel Fiber ◽

Impact Resistance ◽

Strength Properties ◽

Fiber Reinforced Concrete ◽

Curing Conditions ◽

Accelerated Curing ◽

Aspect Ratios ◽

Curing Method

In this study, the effect of curing conditions on the mechanical properties of slurry infiltrated fiber reinforced concrete (SIFCON) was investigated. For this purpose, SIFCON samples containing 4% and 8% steel fiber with two different aspect ratios were produced. The samples were subjected to three different curing types, namely standard, dry and accelerated curing methods. Ultrasonic wave velocity, flexural strength, fracture toughness, compressive strength, impact resistance and capillary water absorption tests were performed on the samples. The highest flexural strength was found to be achieved in the samples with an aspect ratio of 55 and a content of 8% steel fiber. The most suitable curing method was determined as the standard curing method and the best flexural strength was achieved at the rate of 8%. According to the test results, the best strength properties were achieved in the samples exposed to the standard curing method. In addition, the samples exposed to the accelerated curing method showed satisfactory values. The accelerated curing method can be used as an alternative in SIFCON production especially in applications requiring mass production.

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Influence of electron beam irradiation on the mechanical properties of pbat/pla polymeric blend / Influência da irradiação por feixe de electrões nas propriedades mecânicas da mistura polimérica pbat/pla

Brazilian Journal of Development ◽

10.34117/bjdv7n8-252 ◽

2021 ◽

Vol 7 (8) ◽

pp. 79528-79537

Author(s):

Pedro Marcio Munhoz ◽

Fernando Codelo Nascimento ◽

Leonardo Gondim de Andrade e Silva ◽

Julio Harada ◽

Wilson Aparecido Parejo Calvo

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Electron Beam ◽

Electron Beam Irradiation ◽

Impact Resistance ◽

Poly Lactic Acid ◽

Beam Irradiation ◽

Radiation Process ◽

Izod Impact ◽

Polymeric Blend

The aim of this research was to evaluate the changes in the mechanical properties of poly(butylene adipate co-terephthalate)/poly(lactic acid) (PBAT/PLA) polymeric blend after the radiation process at different radiation doses. The irradiation was performed in an electron beam accelerator, with 1.5 MeV of energy and 25 mA electric current. The samples were irradiated with doses of 5, 10, 15, 25, 50, 65 and 80 kGy. Both irradiated and non-irradiated samples were characterized by Izod pendulum impact resistance and tensile strength at rupture. The results showed an increase of 44% in relation to Izod impact resistance at a dose of 65 kGy. However, the module of elasticity decreased 56% and tensile strength at rupture decreased 55% at the same radiation dose. In relation to elongation, significant alterations caused by electron beam irradiation was not observed. Therefore, it can be concluded that irradiated blends could be used to make environmentally friendly products, which could absorb impact energy.

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