MECHANICAL PROPERTIES OF ROTATIONALLY MOLDED PET MICROFIBRIL REINFORCED COMPOSITES

Being a fast growing plastic manufacturing industry, rotational molding has been using the linear polyethylenes extensively as the raw material. As these materials have shown insufficient mechanical properties for certain applications where strength and stiffness of the products are the main concerns, worldwide rotational molders have expressed a need for stronger and stiffer materials to be available for rotomolding. A possible attractive solution may be the recently developed microfibril reinforced composites (MFCs). Blends of linear medium density polyethylene/polyethylene terephthalate (LMDPE/PET) with an MFC structure are manufactured on a commercial-scale set-up and thereafter used in rotational molding. The samples are characterized morphologically and tested mechanically. The results obtained show that the MFC-concept has good application opportunities in the polymer processing including rotational molding.

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Mechanical Strength of Sago/Urea Formaldehyde Particleboard Affected by the Particle Size

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.833.3 ◽

2016 ◽

Vol 833 ◽

pp. 3-10

Author(s):

Tay Chen Chiang ◽

Sinin Hamdan ◽

Mohd Shahril Osman

Keyword(s):

Mechanical Properties ◽

Manufacturing Industry ◽

Urea Formaldehyde ◽

Great Influence ◽

Single Layer ◽

Milling Process ◽

Raw Material ◽

Huge Amount ◽

Testing Method ◽

Sago Waste

Every year, the sago processing industry in Sarawak-Mukah had generated huge amount of sago waste after the milling process and scientists have employ the waste into composite material. The fabrication and testing method are based on the Japanese A5908 Industrial Standard. Single-layer particleboards with targeted density of 600kg/m3 were produced from different sizes of sago particles. The mechanical properties of sago waste were investigated to study the feasibility of using this sample as a raw material in particleboard manufacturing. The results of the test demonstrate that samples with different sizes of particles have great influence on the mechanical properties such as Young’s Modulus, Tensile Strength and Impact Strength. The findings show that the performance of the board is affected by the different sizes of sago particles used in the experiment and had proved that sago plants can be used as an alternative raw material in the particleboard manufacturing industry.

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Effect of fiber sizing on Mechanical properties of carbon reinforced composites: A Review

Organic Polymer Material Research ◽

10.30564/opmr.v1i2.1683 ◽

2020 ◽

Vol 1 (2) ◽

Author(s):

Mayank Agrawal

Keyword(s):

Mechanical Properties ◽

Carbon Fiber ◽

Reinforced Composites ◽

Strength And Stiffness ◽

Properties Of Composites

Present study focuses on the carbon fiber sizing and their effect on overall mechanical properties of composites. Fiber sizing are one of the most important component in the manufacturing of composites. As the sizing are so much of importance in the manufacturing and development of composites which governs mechanical properties such as strength and stiffness. In this review some of the important articles are referred from the widely dispersed literature. This review covers the sizing effect, adhesion between fiber and matrix and characterization of composites

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Human Scalp Hair as Fiber Reinforcement in Cement Concrete

Mehran University Research Journal of Engineering and Technology ◽

10.22581/muet1982.2002.20 ◽

2020 ◽

Vol 39 (2) ◽

pp. 443-452

Author(s):

Shanker Lal Meghwar ◽

Ghous Bux Khaskheli ◽

Aneel Kumar

Keyword(s):

Mechanical Properties ◽

Natural Resources ◽

Manufacturing Industry ◽

Scalp Hair ◽

Testing Machine ◽

Raw Material ◽

Sustainable Construction ◽

Cement Concrete ◽

Human Scalp Hair ◽

Concrete Mix

The construction industry is the largest manufacturing industry, which produces concrete and other related materials for construction of infrastructure around the world, after the food production industry. This industry requires a lot of natural resources like aggregates, limestone etc. to produce finished product such as concrete and cement. These natural resources are limited and have to deplete one day, so alternate to these resources are required. On the other hand, this industry produces a large amount of waste material that creates environmental pollution. Thus, recycling the waste as potential raw material and to produce a usable product is the need of present era for sustainable construction. This study presents the quantitative analysis of HSH (Human Scalp Hair) as fibers in cement concrete. This study aims to investigate the behaviour of concrete in terms of their mechanical properties when HSH are used as fibers. A detailed investigation on two types of concrete specimens i.e. cylindrical (150 mm diameter and 300 mm height) and prism (150 mm depth, width and 600 mm length) made with a different proportion of HSH as fibers and concrete mix ratios, was carried out. In this study, various proportions of HSH added in concrete that includes 0%, 1%, 2% and 3% by weight of OPC (Ordinary Portland Cement). All specimens were cast at two concrete mix ratios i.e. 1:2:4 and 1:1.5:3 with 0.50 W/C (Water-Cement Ratio). Moreover, specimens were tested in UTM (Universal Testing Machine) at 28 days curing age, for splitting tensile strength and flexural strength of concrete. It was observed from the experimental analysis that there is an improvement in mechanical properties of concrete at specific percentage of HSH and reduction of workability and density with increasing percentages of HSH.

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Microstructures and Mechanical Properties of Natural Fibers

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.33-37.553 ◽

2008 ◽

Vol 33-37 ◽

pp. 553-558 ◽

Cited By ~ 5

Author(s):

Yan Li ◽

Yan Ping Hu ◽

Chun Jing Hu ◽

Ye Hong Yu

Keyword(s):

Mechanical Properties ◽

Moisture Absorption ◽

Natural Fiber ◽

Natural Fibers ◽

Fiber Reinforced Composites ◽

Reinforced Composites ◽

Fiber Reinforced ◽

Specific Strength ◽

Mechanical Performances ◽

Set Up

Natural fibers are excellent substitute materials for man made fibers in making fiber reinforced composites due to their high specific strength and modulus, low density, low price, easy availability in some countries, recyclable and degradable properties. They have raised great attentions among material scientists and engineers in the past decade. Many researches have been conducted to study the mechanical properties, especially interfacial properties of natural fiber reinforced composites. However, the properties, such as mechanical performances, moisture absorption behaviors, et. al of natural fibers themselves have been seldom investigated. Knowing the relationship between microstructures and properties of natural fibers are important for understanding the bulk properties of natural fiber composites and also good instructions for designing bio-mimic materials. In this study, four kinds of natural fibers which were extracted from different plant sources were investigated. The microstructures of these natural fibers were revealed with the aid of optical microscopy. Microstructure models were thereof set up and mechanical properties for the representative volume element were assumed. Fiber bundle fracture models together with probability statistics analysis were employed to calculate the mechanical properties of natural fibers. The results were compared with the experimental measurements. Different mechanical behaviors of natural fibers which were functioned differently in the nature were clearly explained by the above studies

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Mechanical Properties of Polypropylene Warp-Knitted Hernia Repair Mesh with Different Pull Densities

Polymers ◽

10.3390/polym10121322 ◽

2018 ◽

Vol 10 (12) ◽

pp. 1322

Author(s):

Wanli Xu ◽

Pibo Ma ◽

Gaoming Jiang ◽

Ailan Wan

Keyword(s):

Mechanical Properties ◽

Tensile Stress ◽

High Speed ◽

Vertical Direction ◽

Horizontal Stress ◽

Raw Material ◽

Knitted Fabrics ◽

Polypropylene Monofilament ◽

Set Up ◽

Warp Knitted Fabric

The medical polypropylene monofilament with a diameter of 0.10 mm was used as the material. Four different pull densities and two different warp run-ins were set up on the electronic traverse high-speed Tricot warp knitting machine, with the gauge of E28. The raw material was used to knit four variations of single bar plain knitted fabrics with 1 in-1 miss setting. Each variation required eight samples. The mechanical properties of the above 32 warp-knitted fabric samples are tested, including their tensile stress (in both vertical and horizontal directions), tearing stress (in both vertical and horizontal directions) and bursting stress. The results obtained shows that the relationship between the vertical, the horizontal stress, and the pull density are not monotonic. The tensile stress in the vertical direction firstly decreases and then increases with an increase of the pull density; however, the tensile stress in the horizontal direction firstly increases and then slightly decreases with an increase of the pull density; again the vertical tensile stress of all fabrics was always higher than the horizontal tensile stress. The bursting stress has a positive linear relation to the pull density. The vertical tearing stresses of four samples were greater than the horizontal tearing stress.

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Physical and Mechanical Properties of Jute Mat Reinforced Epoxy Composites

ASEAN Journal on Science and Technology for Development ◽

10.29037/ajstd.38 ◽

2011 ◽

Vol 28 (2) ◽

pp. 115

Author(s):

S.M Sadaf ◽

M Siddik ◽

Q Ahsan

Keyword(s):

Mechanical Properties ◽

Volume Fraction ◽

Physical And Mechanical Properties ◽

High Volume ◽

Matrix Composites ◽

Reinforced Composites ◽

Specific Strength ◽

Pull Out ◽

Lower Volume ◽

Strength And Stiffness

Cellulose jute fibre offers a number of benefits as reinforcement for synthetic polymers since it has a high specific strength and stiffness, low hardness, relatively low density and biodegradability. To reduce moisture uptake and hence to improve the mechanical properties of the composites, bleached jute mats were incorporated as reinforcing elements in the epoxy matrix. Composites at varying volume fractions and different orientations of jute mat were fabricated by hot compression machine under specific pressures and temperatures. Tensile, flexure, impact and water absorption tests of composites were conducted. Jute mat oriented at (0 ± 45–90)° composites showed reduced strength compared to (0–90)° fibre mat composites. Impact strength and water uptake of high volume fraction jute mat reinforced composites was higher compared to that of lower volume fraction composites. Fracture surfaces of jute mat composites were analyzed under SEM. Fracture surface of (0–90)° jute mat oriented composites showed twisted fibres, while (0 ± 45–90)° jute mat oriented composites had fibre pull-out without any twisting. Overall, composites containing 52% jute mat at orientations of (0–90)° showed better properties compared to other fabricated composites.

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Morphological and Mechanical Properties of Bilayers Wood-Plastic Composites and Foams Obtained by Rotational Molding

Polymers ◽

10.3390/polym12030503 ◽

2020 ◽

Vol 12 (3) ◽

pp. 503 ◽

Cited By ~ 4

Author(s):

Roberto Carlos Vázquez Fletes ◽

Erick Omar Cisneros López ◽

Francisco Javier Moscoso Sánchez ◽

Eduardo Mendizábal ◽

Rubén González Núñez ◽

...

Keyword(s):

Mechanical Properties ◽

Industrial Waste ◽

Medium Density ◽

Rotational Molding ◽

External Layer ◽

Complete Understanding ◽

Blowing Agent ◽

Density Reduction ◽

Plastic Composites ◽

Structure Properties

In this work, the suitability for the production of sustainable and lightweight materials with specific mechanical properties and potentially lower costs was studied. Agave fiber (AF), an agro-industrial waste, was used as a reinforcement and azodicarbonamide (ACA) as a chemical blowing agent (CBA) in the production of bilayer materials via rotational molding. The external layer was a composite of linear medium density polyethylene (LMDPE) with different AF contents (0–15 wt %), while the internal layer was foamed LMDPE (using 0–0.75 wt % ACA). The samples were characterized in terms of thermal, morphological and mechanical properties to obtain a complete understanding of the structure-properties relationships. Increases in the thicknesses of the parts (up to 127%) and a bulk density reduction were obtained by using ACA (0.75 wt %) and AF (15 wt %). Further, the addition of AF increased the tensile (23%) and flexural (29%) moduli compared to the neat LMDPE, but when ACA was used, lower values (75% and 56% for the tensile and flexural moduli, respectively) were obtained. Based on these results, a balance between mechanical properties and lightweight can be achieved by selecting the AF and ACA contents, as well as the performance and aesthetics properties of the rotomolded parts.

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Observing the relaxation of molecular orientation in sheared liquid crystalline polymer solutions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100178598 ◽

1990 ◽

Vol 48 (4) ◽

pp. 1092-1093

Author(s):

Wendy Putnam ◽

Christopher Viney

Keyword(s):

Molecular Orientation ◽

Liquid Crystalline Polymer ◽

Liquid Crystalline ◽

Crystalline Polymer ◽

Polymer Processing ◽

Molecular Alignment ◽

Global Alignment ◽

Shear Direction ◽

Axial Strength ◽

Strength And Stiffness

Liquid crystalline polymers (solutions or melts) can be spun into fibers and films that have a higher axial strength and stiffness than conventionally processed polymers. These superior properties are due to the spontaneous molecular extension and alignment that is characteristic of liquid crystalline phases. Much of the effort in processing conventional polymers goes into extending and aligning the chains, while, in liquid crystalline polymer processing, the primary microstructural rearrangement involves converting local molecular alignment into global molecular alignment. Unfortunately, the global alignment introduced by processing relaxes quickly upon cessation of shear, and the molecular orientation develops a periodic misalignment relative to the shear direction. The axial strength and stiffness are reduced by this relaxation.Clearly there is a need to solidify the liquid crystalline state (i.e. remove heat or solvent) before significant relaxation occurs. Several researchers have observed this relaxation, mainly in solutions of hydroxypropyl cellulose (HPC) because they are lyotropic under ambient conditions.

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