Production of Prosthetics and orthotics materials with improved tensile strength and elongation at break from venial acetate, lowdensity polyethylene and additive blends

  IJETT-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
© 2017 by IJETT Journal
Volume-52 Number-3
Year of Publication : 2017
Authors : Asmamaw Tegegne, Yenealem Yilma
DOI :  10.14445/22315381/IJETT-V52P225


Asmamaw Tegegne, Yenealem Yilma "Production of Prosthetics and orthotics materials with improved tensile strength and elongation at break from venial acetate, lowdensity polyethylene and additive blends", International Journal of Engineering Trends and Technology (IJETT), V52(3),162-174 October 2017. ISSN:2231-5381. published by seventh sense research group

Polymers including Ethylene vinyl acetate (EVA) and low density polyethylene (LDPE) are some of the useful materials for different engineering applications including artificial legs, hands or prosthetic and orthotics. In most countries in Africa (particularly in Ethiopia) prosthetic and orthotics service is mostly applicable in limited hospitals. Raw materials (pure EVA) are brought from abroad and molding is carried out locally. This time provision of raw materials is reduced due to lack of supplier. Moreover the mechanical properties of these materials have certain draw backs on service properties .Some of the problems are high thermal expansion, poor weather resistance subjected to stress cracking, failure in strength . To alleviate these problems it is required to produce the raw materials locally with improved mechanical properties that prolong the service life, as result of which the foreign currency will be saved. The objective of this research is thus to produce prosthetic and orthotics raw materials from EVA/LDPE blend with improved tensile strength and elongation. To carry out this research thermoplastic LDPE, EVA, color pigment, calcium carbonate, and black carbons were used as charged materials (constituents). Samples were produced in sheet form for further analysis. The research was conducted experimental ly. Blending, molding, and testing of the produced material were carried out using different appropriate devices, tools and equipment. It was observed that the addition of additives improve the mechanical properties especially tensile strength. From the gauge reading it was recorded that the maximum tensile strength was 10.5 M pa and the minimum tensile strength was 2.8 Mpa, at the same time the maximum elongation at break was 469.8% and the minimum elongation at break 40.2%. The other results were in between these ranges, which are better than the material sample produced from pure EVA (maximum tensile strength of 2.3 Mpa and the elongation of 265 %). It is expected that the result of the research will reduce the foreign exchange consumption of the country and satisfy the demand of hospitals and patients.

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Prosthetic, Orthotic, Blending, Low density poly ethylene, Ethylene vinyl acetate, Mechanical property.