Toughness and Impact Strength in Dynamic Bending of Wood as a Function of the Modulus of Elasticity and the Strength in Compression to the Grain

This study aims to explore the tensile and impact properties (tensile strength, modulus of elasticity, and impact strength) of polypropylene (PP)-based nanocomposites reinforced with graphene nanosheets, nanoclay, and basalt fibers. The response surface methodology (RSM) with Box–Behnken design (BBD) was adopted as the experimental design. An internal mixer was used to prepare compounds consisting of 0, 0.75 and 1.5 wt% graphene nanosheets, 0, 10 and 20 wt% basalt fibers, and 0, 3 and 6 wt% nanoclay. The samples were prepared by a hot press machine for mechanical testing. The tensile tests were run to determine the tensile strength, and modulus of elasticity, and the Charpy impact tests were performed to assess the impact strength. It was found that the addition of basalt increased the tensile strength, modulus of elasticity, and impact strength by 32%, 64% and 18%, respectively. Also, the incorporation of the low-weight graphene nanosheets increased the tensile and impact strength by 15% and 20%, respectively, Adding graphene nanosheets generally improved the modulus of elasticity by 66%. Similarly, the addition of nanoclay improved the tensile strength by 17% and increased the modulus of elasticity by 59%, but further addition of it decreased the impact strength by 19%. The values obtained by this experiment for the mechanical property were roughly close to the data yielded from desirability optimization.

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Fiber-Reinforced Mortar Incorporating Pig Hair

Advanced Engineering Forum ◽

10.4028/www.scientific.net/aef.21.219 ◽

2017 ◽

Vol 21 ◽

pp. 219-225 ◽

Cited By ~ 10

Author(s):

Gerardo Araya-Letelier ◽

Federico C. Antico ◽

Pablo Fernado Parra ◽

Miguel Carrasco

Keyword(s):

Impact Strength ◽

Bulk Density ◽

Environmental Impacts ◽

Modulus Of Elasticity ◽

Dynamic Modulus ◽

Food Industry ◽

Fiber Reinforced ◽

Dynamic Modulus Of Elasticity ◽

Cement Based Materials ◽

The Impact

Recycled fibers from food-industry could be added as reinforcement to cement-based materials. Cement-based materials perform well under compression, but tensile strength and post-cracking ductility in tension are poor. Fibers produced from steel, glass and synthetic materials, have been successfully used to overcome some of these shortcomings. Fiber-reinforced mortar has shown an increased post-cracking ductility and improved long-term serviceability due to the crack control provided by fibers. Food-industry waste disposal is globally a major concern because of its environmental impacts. For these reasons, the use of recycled materials in construction applications has been investigated over the last decades. This investigation deals with the incorporation of pig hair, which is a waste produced by the food-industry worldwide, in fiber-reinforced mortars. This composite material is intended to reduce the environmental impacts by valuing waste materials in construction applications while improving mechanical properties. To determine compressive, flexural and impact strength, bulk density, porosity and dynamic modulus of elasticity laboratory tests were conducted in mortar specimens with 0%, and 2% of pig-hair content in weight of cement. The results of this research show that the impact strength can increase up to five times when compared to plain mortar. Moreover, the compressive and flexural strengths, bulk density, porosity and the dynamic modulus of elasticity of fiber-reinforced mortar, with the aforementioned pig-hair content, are not significantly affected.

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ANALYSIS OF THE FIRE‐PROTECTION IMPREGNATION INFLUENCE ON WOOD STRENGTH

Journal of Civil Engineering and Management ◽

10.3846/13923730.2007.9636423 ◽

2007 ◽

Vol 13 (2) ◽

pp. 79-85 ◽

Cited By ~ 10

Author(s):

Zoja Bednarek ◽

Agnieszka Kaliszuk-Wietecka

Keyword(s):

Impact Strength ◽

Fire Protection ◽

Elevated Temperatures ◽

Pressure Method ◽

Dynamic Bending ◽

Result Analysis ◽

Wood Strength

The paper presents the description, results and result analysis for the effect of fire‐protection impregnation with a salt‐containing agent, made by a vacuum‐and‐pressure method, on wood strength. A significant effect of this impregnation type was proven for the strength types as follows: static bending, tension, lengthwise compression (ie along fibres), crosswise compression (ie across fibres), as well as for dynamic bending and impact strength in normal and elevated temperatures.

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Effect of Ading Nanocarbon Black on the Mechanical Properties of Epoxy

Diyala Journal of Engineering Sciences ◽

10.24237/djes.2014.07107 ◽

2014 ◽

Vol 7 (1) ◽

pp. 94-108

Author(s):

Amer Hameed Majeed ◽

Mohammed S. Hamza ◽

Hayder Raheem Kareem

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Compressive Strength ◽

Impact Strength ◽

Flexural Strength ◽

Carbon Black ◽

Modulus Of Elasticity ◽

Tensile Modulus ◽

Dispersion Method ◽

Carbon Black Nanoparticles

The study covers the effect of nanocarbon black particles (N220) on some important mechanical properties of epoxy reinforced with it [carbon black nanoparticles]. The nanocomposites were prepared with (1 to 10 wt. %) of carbon black nanoparticles using ultrasonic wave bath machine dispersion method. The results had shown that the tensile strength , tensile modulus of elasticity, flexural strength and impact strength are improved by (24.02%,7.93%,17.3% and 6% ) respectively at 2wt % .The compressive strength and hardness are improved by (44.4%, 12%) at 4wt%.

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Buna for Hard Rubber Linings

Rubber Chemistry and Technology ◽

10.5254/1.3540086 ◽

1941 ◽

Vol 14 (4) ◽

pp. 899-913 ◽

Cited By ~ 1

Author(s):

E. Gartner

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Impact Strength ◽

Natural Rubber ◽

Narrow Range ◽

Brinell Hardness ◽

Good Material ◽

Shock Resistance ◽

Dynamic Bending

Abstract On the basis of the investigations described in the present paper, certain rules or directions for obtaining the most desirable properties with the various types of artificial rubbers can be laid down. Brinell hardness.—The higher the proportion of vinyl component in a mixed butadiene polymer, the harder is the resulting vulcanizate within the relatively narrow range of percentages of sulfur which were tested. In this respect, acrylonitrile has a greater effect than does styrene. Mechanical properties.—As far as mechanical properties are concerned, Perbunan-Extra is an extraordinarily good material for, in addition to giving high Brinell hardness and tensile strength, it also shows good shock resistance and impact strength. Buna-SS and Perbunan-Extra give, within the range of hardnesses tested, high Martens values. Compared with natural rubber, their resistances to dynamic bending are particularly good.

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PHYSICAL AND MECHANICAL AND THERMOPHYSICAL PROPERTIES OF POLYMER COMPOSITES BASED ON RECYCLED POLYPROPYLENE FILLED WITH RICE HUSK

Periódico Tchê Química ◽

10.52571/ptq.v17.n35.2020.60_sadritdinov_pgs_703_712.pdf ◽

2020 ◽

Vol 17 (35) ◽

pp. 703-712

Author(s):

Aynur R. SADRITDINOV ◽

Aygiz G. KHUSNULLIN ◽

Artur A. PSYANCHIN ◽

Elena M. ZAKHAROVA ◽

Vadim P. ZAKHAROV

Keyword(s):

Tensile Strength ◽

Impact Strength ◽

Polymer Composites ◽

Rice Husk ◽

Impact Energy ◽

Thermophysical Properties ◽

Modulus Of Elasticity ◽

Izod Impact Strength ◽

Recycled Polypropylene ◽

Izod Impact

The relevance of the study is due to the deterioration of the environmental situation in the world associated with an increase of plastic waste, which determines the feasibility of developing methods for their involvement in recycling for the production of plastic products. Thereby, this article is aimed at studying the patterns of changes in the physical and mechanical and thermophysical properties of polymer composites based on recycled polypropylene filled with rice husk in the absence of compatibilizers. The leading approach to the study of this problem is the determination of the modulus of elasticity in flexure, tensile strength at break, strain-to-failure, and bending strain, bending temperature under load and Vicat softening temperature, Charpy V-notch impact energy and Izod impact strength, as well as the thermophysical parameters of polymer composites. The article shows that with an increase in the content of rice husk in a polymer composite based on recycled polypropylene, an increase in the modulus of elasticity in flexure occurs. Filling polypropylene with rice husk slightly reduces the tensile strength and significantly reduces the elasticity of the polymer. Recycled polypropylene has a higher Charpy V-notch impact energy than Izod impact strength. Filling the polymer with rice husk leads to a decrease in impact strength according to both Charpy and Izod, and with a compound content of more than 5 phr, both of these indicators are almost identical. In this case, there is a slight increase in the onset temperature of the composites, which determines their thermal stability during processing. It was revealed that polymer composites containing 2-10 mass parts of rice husk are characterized by an increased degree of crystallinity of the polymer phase. The materials of the article are of practical value for the processing of recycled thermoplastic polymers, as well as the creation of biodegradable polymer composites.

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Inﬂ uence of Na+-montmorillonite modiﬁ ed with acrylamide on the structure and properties of polypropylene

Plasticheskie massy ◽

10.35164/0554-2901-2020-3-4-26-29 ◽

2020 ◽

pp. 26-29

Author(s):

M. B. Begieva ◽

D. B. Amshokova ◽

L. R. Pashtova ◽

R. CH. Bazheva ◽

A. M. Kharaev

Keyword(s):

Mechanical Properties ◽

Impact Strength ◽

Modulus Of Elasticity ◽

Large Scale ◽

Tensile Modulus ◽

Physical And Mechanical Properties ◽

Scale Production ◽

Melt Mixing ◽

Twin Screw ◽

Sodium Form

Sodium form montmorillonite was obtained from natural clay from the Gerpegezh deposit (Kabardino-Balkarian Republic, Russia). A procedure has been developed for modifying the sodium form of montmorillonite using acrylamide. The structure of the organoclay was conﬁ rmed by IR spectroscopy. Composites based on polypropylene and modiﬁ ed montmorillonite are obtained by melt mixing on a twin-screw extruder from JiangsuXindaScience & Technology. The structure of the obtained composites was investigated using X-ray diﬀ raction analysis and scanning electron microscopy. The results of testing the obtained composites, which were used to evaluate the physical and mechanical properties, are presented: the melt ﬂ ow index, impact strength according to Izod, modulus of elasticity, ultimate strength and elongation at break. ICompared to unﬁ lled polypropylene, polymer composites with 3 wt.% organoclay are shown to increase: impact strength by 31.61% (without notch) and 12.8% (with notch of 5 mm); modulus of elasticity in bending by 8.3%; tensile modulus by 10,3%. When polypropylene is ﬁ lled with 5 wt.% organoclay, the composites show increased: impact strength by 12.60% (without notch) and by 10.52% (with an notch of 5 mm); the modulus of elasticity in bending and tension are the same as in the previous case. A further increase in the content of organoclay to 7 wt.% leads to a slight decrease in mechanical properties. Acrylamide can be used as a modiﬁ er of organic clay; it is easily accessible and cheap, used in large-scale production. The resulting composites can be used as structural materials.

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Effects of multiple extrusions on structure–property relationships of hybrid wood flour/poly (vinyl chloride) composites

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705720930737 ◽

2020 ◽

pp. 089270572093073

Author(s):

Elham Nadali ◽

Reza Naghdi

Keyword(s):

Impact Strength ◽

Water Absorption ◽

Vinyl Chloride ◽

Modulus Of Elasticity ◽

Bending Strength ◽

Wood Flour ◽

Hydroxyl Groups ◽

Structure Property ◽

Poly Vinyl Chloride ◽

Recycled Composites

This study emphasizes on closed-loop recycling of wood flour/poly (vinyl chloride) composites, since there is normally a considerable amount of material waste in wood plastic production lines. Composite materials were produced and subjected to four times reprocessing cycles under industrial conditions. Detailed analytical methods including bending strength, modulus of elasticity, impact strength, scanning electron microscopy, fiber length, water absorption, contact angle, Fourier transform infrared, and dynamic mechanical thermal analysis (DMTA) were conducted to evaluate the effects of recycling on the mentioned composites. Results demonstrated that the recycled composites, except for the four-time recycled ones, had lower bending strength, modulus of elasticity, and impact strength due to fiber-chain scission/fracture resulting from shear stress during reprocessing; however, impact strength remained almost unchanged after the first recycling cycle. Results also revealed that generally the reprocessed composites showed lower water absorption rates due to better fiber wetting and encapsulation. There was also a reduction in hemicellulose hydroxyl groups, rendering the recycled composites less hydrophilic. DMTA results showed an increase in mechanical loss factor (tan δ) for all the reprocessed composites showing a more viscous than elastic nature. The glass transition temperature of Rec4 composites increased due to polymer dehydrochlorination and the resulting cross-linking, which restricted the molecular mobility of the polymer chains.

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Mechanical, electrical and tribological properties of graphite filled polyamide-6 composite materials

Journal of Polymer Engineering ◽

10.1515/polyeng-2013-0043 ◽

2013 ◽

Vol 33 (4) ◽

pp. 351-355 ◽

Cited By ~ 6

Author(s):

Huseyin Unal ◽

Kadir Esmer ◽

Abdullah Mimaroglu

Keyword(s):

Tensile Strength ◽

Dielectric Permittivity ◽

Impact Strength ◽

Wear Rate ◽

Tribological Properties ◽

Modulus Of Elasticity ◽

Weight Ratio ◽

Nylon 6 ◽

Specific Wear Rate ◽

Elongation At Break

Abstract In this study, the influence of adding graphite filler, on the mechanical, electrical and tribological properties of nylon-6 composites, is studied. Graphite fillers with different percentages, varying between 5 and 15 wt% were added to nylon-6 polymer material. Nylon-6 composite samples were prepared by the injection molding process. Tensile, impact, electrical and tribological tests were carried out and the dielectric permittivity tangent loss factor, tensile strength, modulus of elasticity, elongation at break, impact strength, specific wear rate and coefficient of friction properties were obtained. The results showed that the tensile strength, elongation at break, impact strength, and specific wear rate of nylon-6 composites, decrease with the increase in graphite filler weight ratio, while the modulus of elasticity, hardness, real part of dielectric permittivity, imaginary part of dielectric permittivity and dielectric loss, increase with increase in the filler weight ratio. Furthermore, it is observed that a rise in the relaxation time of ionic polarization is proportional to the increase in the amount of graphite in the medium and the dielectric conductivity and loss decrease proportionally after approximately 10 KHz. Finally, the maximum improvement in properties, in total, is recorded following the addition of 5 to 10 wt% graphite filler.

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Improvement of Impact Strength of Polystyrene by Compounding with Styrene-Grafted Ethylene Propylene Elastomeric Copolymers

Rubber Chemistry and Technology ◽

10.5254/1.3547081 ◽

1966 ◽

Vol 39 (5) ◽

pp. 1667-1675 ◽

Cited By ~ 2

Author(s):

G. Natta ◽

M. Pegoraro ◽

F. Severini ◽

S. Dabhade

Keyword(s):

Impact Strength ◽

Modulus Of Elasticity ◽

Polymeric Materials ◽

Graft Polymer ◽

Ethylene Propylene ◽

Polystyrene Matrix

Abstract Ethylene propylene copolymers having good elastomeric properties lend themselves very well to improving impact strength of fragile polymeric materials, such as polystyrene. In order to obtain good results, the percentage of copolymer to be added should be chosen in such a way that the strength of the resulting mixture is as high as possible, but compatible, however, with the practically useful values of the hardness and of the modulus of elasticity, which decrease regularly with an increase in the percentage of elastomer. The best results, for an equal percentage of elastomer, are obtained when the polystyrene is mixed with polystyrene grafted on the ethylene propylene copolymer, rather than with the ethylene propylene copolymer alone. This we attribute to the improved dispersion of the elastomer in the polystyrene matrix that is found in case of the use of the graft polymer. Thus, formation of vitreous and elastomeric microphases, rather than of macrophases, occurs, and there is a better adhesion between these. The use of a graft polymer prevents, in practice, the phenomena of migration and sorting of the phases, and guarantees the maintenance over a period of time of a microphasic structure. The use of a saturated elastomer, such as that used by us, permits, additionally, an improvement in the resistance to aging, in comparison with the traditional materials consisting of mixtures of polystyrene and unsaturated elastomers.

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