SIPS 2018

DETAILLED PROGRAM OVERVIEW

Rice Husks Fibre Reinforced Polypropylene Composites for Structural Reuse - A Technological Solution to an Environmental Challenge in Sub-Saharan Africa
Edward Odhong¹; Alex Munyasya Muumbo²; Abel N. Mayaka³;
¹MULTIMEDIA UNIVERSITY OF KENYA, NAIROBI, Kenya; ²THE TECHNICAL UNIVERSITY OF KENYA, Nairobi, Kenya; ³MULTIMEDIA UNIVERSITY OF KENYA, Nairobi, Kenya;
PAPER: 26/Composite/Regular (Oral)
SCHEDULED: 16:20/Mon./Grego (50/3rd)

ABSTRACT:
Africa is facing a serious crisis, due to serious environmental degradation arising from the economic exploitation of its forests. A possible mitigating measure would be the development and provision of alternative cheap structural materials to replace timber.
A good cheap alternative material is plant fibre reinforced polymer composite. Use of rice husk fiber reinforced polymer composite minimizes environmental pollution due to characteristic biodegradability [1]. Engineering materials fail when loaded beyond their elastic limit by fracture or plastic deformation. Structures made from healable materials have significantly prolonged service life [2]. A rice husk fibre reinforced polypropylene composite will undergo failure that involves crack initiation, propagation, and complete fracture [3]. Rice husk fibre reinforced polypropylene composite forms a chemical or frictional bond, whose strength largely depends on strength of the interface [4].
In this research, rice husk fibres were prepared by hammer milling, heated to reduce moisture content and surface modification done to increase wettability by the matrix. Polypropylene wastes were shredded and used as matrix [5]. Composite test pieces were produced by film stacking technique and by injection moulding. Respective standards were applied during destructive testing and mechanical properties were compared with existing published results. The resulting strengths were: Tensile 85 MPa, bending 56 MPa, Compressive 178 MPa, impact 61 J/mm² and hardness BHN 480. These results gave mechanical performance sufficient to conclude that the reinforced composite material could be used to replace timber and save forests which are depleting.
The fractured test pieces were repaired / healed and then retested for respective mechanical properties. Percentage recovered strengths from tensile, impact and compressive strength tests were 81, 98.36 and 95 respectively. It could be concluded that repaired rice husk fibre reinforced polypropylene composites could be reused for their original specific structural functions thus further minimizing need for forest products for similar applications.

References:
[1] HGB. Premalal, H. Ismail, A. Baharin Comparison of the mechanical properties of rice husk powder filled polypropylene composites with talc filled polypropylene composites. Polymer Testing. 2002;21(7):833-9.
[2] M. Hautier, D. LAi��vAi��que, C. Huchette , and P. Olivier. 2015. Investigation of a composite repair method by liquid resin infusion. 29 av. de la Division Leclerc, 92322 Chatillon, France *UniversitAi�� de Toulouse, UPS, IUT P. Sabatier, IGM-LGMT DAi��pt. GMP - 133C av. de Rangueil, B.P., 67701 - 31077 Toulouse CEDEX 4, France mathieu.hautier@onera.fr.
[3] H.S. Yang, J.K. Kim,, J. Son,, H.,J. Park, B.,J. Lee, T.,S. Hwang, Rice husk
flour filled polypropylene composites; mechanical and morphological study,
Composite Structure, 2004; 63, p.305-312. [4] F. Uchenna, O. Dimzoski, G. Bogoeva-Gaceva, G. Gentile, M. Avella and A. Grozdanov, "Polypropylene-based Eco-composites Filled with Agricultural Rice Hulls Waste", Chem. Biochem. Eng. Q. 23 (2), Page No. 225-230, 2009.
[5] B. Hayes. 2014.Improved Resin Injection Repairs for Polymer Composite Materials Applied Poleramic, Inc. 6166 Egret Court. Benicia, California, 94510- 94569.