Effects of Surface Treatment of Ground Rice Husk on the Polyurethane Based on Castor Oil

In this study, a biodegradable, cheap and durable recycled high-density polyethylene (rHDPE) polymer reinforced with rice husk (RH) fibre was fabricated into a foam structure through several processes, including extrusion, internal mixing and hot pressing. The effect of filler loading on the properties of the foam and the influence of RH surface treatments on the filler–matrix adhesion and mechanical properties of the composite foam were investigated. The morphological examination shows that 50 wt.% filler content resulted in an effective dispersion of cells with the smallest cell size (58.3 µm) and the highest density (7.62 × 1011 sel/cm3). This small cell size benefits the mechanical properties. Results indicate that the tensile strength and the Young’s modulus of the alkali-treated RH/rHDPE composite foam are the highest amongst the treatments (10.83 MPa and 858 MPa, respectively), followed by UV/O3, which has shown considerable increments compared with the untreated composite. The flexural and impact tests also show the increment in strength for the composite foam after chemical treatment. Although the UV/O3 surface treatment has minor influence on the mechanical enhancement of the composite foam, this method may be a reliable surface treatment of the fibre-reinforced composite.

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Influence of different surface treatment techniques on properties of rice husk incorporated polymer composites

Reviews in Chemical Engineering ◽

10.1515/revce-2019-0027 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Obinna Emmanuel Ezenkwa ◽

Azman Hassan ◽

Sani Amril Samsudin

Keyword(s):

Surface Modification ◽

Surface Treatment ◽

Polymer Composites ◽

Rice Husk ◽

Natural Fiber ◽

Low Cost ◽

Treatment Techniques ◽

Plastic Composites ◽

Surface Modification Techniques ◽

Composite Properties

AbstractRice husk natural fiber remains a highly abundant, eco-friendly and low-cost reinforcement filler for plastic composites fabrication. Hampered by its low aspect ratio and incompatibility with non-polar polymers, its utilization in reinforcing polymer composites often results in decreased composite properties such as decreased tensile strength, impact strength, percentage elongation, and flexural strength. However, stiffness increases. Various surface treatment techniques such as mercerization, compatibilization, acetylation, electron beam irradiation and plasma surface modification have been employed to improve its compatibility with non-polar matrix polymers. This article critically reviews the influence of these surface modification techniques on the resulting composite properties. Based on the analysis of reinforcing efficiencies of these techniques, their strengths, weaknesses, opportunities, and threats, the authors, therefore, project plasma treatment as the most efficient and eco-friendly technique with prospects for high technological application of rice husk plastic composites.

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