DBPapers
DOI: 10.5593/sgem2017/62/S26.014

ECOCOMPOSITES BASED ON NATURAL RUBBER AND PLASTICIZED STARCH

M. D. Stelescu, M.Georgescu, L. Alexandrescu, M. Sönmez, M. Niţuică
Tuesday 12 September 2017 by Libadmin2017

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7408-13-3 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 62, 105-114 pp, DOI: 10.5593/sgem2017/62/S26.014

ABSTRACT

This paper presents studies on the development of ecocomposites based on natural rubber and plasticized starch. Natural rubber is the most commonly used elastomer worldwide due to its low cost; it is renewable, non-toxic and shows excellent physical properties. Natural rubber is not used as such but in the form of mixtures which generally contain: fillers, plasticizers, crosslinking agents and other ingredients that provide various features to the final product. Replacement of active fillers in rubber mixtures such as carbon black or silica (which have adverse effects on health) with a biodegradable filler, such as starch provides many advantages, namely: environmental protection, non-toxicity, low density and cost, etc. Ecocomposites were made containing 10 phr, 20 phr, and 30 phr starch, respectively. Starch was plasticized and then incorporated in natural rubber in the roll mill, and then other ingredients were added (compatibilizer, curing agents, antioxidant); the resulting mixtures were cured in an electrical press. The physico-mechanical and chemical characteristics of resulting composites depends on the amount of plasticized starch added to the rubber mixture, as follows: (a) hardness increases while elasticity decreases due to the increased amount of plasticized starch in the mixture, indicating that a reinforced rubber mixture may be obtained by replacing the inorganic filler; (b) tensile strength increases, elongation at break decreases and tear strength has a non-uniform variation; (c) the optimal curing time decreases; (d) mass variation in: water, ethyl alcohol, sunflower oil, 10% glucose solution, 0.9% sodium chloride solution for 22 h has values below 15%. Ecocomposites can be used to obtain products with applications in the food industry, pharmaceutical industry, agriculture, etc.

Keywords: ecocomposites, natural rubber, starch, characteristics