Water absorption and its effect on mechanical properties of sisal composite

Abstract

Apart from many applications of natural fibres reinforced polymer composites, still they are not being used in outdoor applications because of their higher water absorption thereby degradation in mechanical properties. The purpose of this study is to analyze the water absorption behaviour and its effect on tensile, flexural and impact properties of sisal composites. Water absorption characteristic parameters such as sorption, diffusion and permeability coefficient were also investigated. The composites were prepared by hand lay-up method followed by a constant loading with varying fibres lengths (i.e. 5, 10, 15 and 20 mm). In addition to this, fibres content was kept constant (i.e. 20 wt. %) in each composite. The results showed a significant effect of water absorption and fibres lengths on the mechanical properties of sisal composites. Mechanical properties were found to increase up to a certain fibres length (15 mm) and then decreased. On the other hand, mechanical properties of sisal composites were reduced after water absorption. There were (10–18)%, (10–21)% and (16–30)% deduction in tensile strength, flexural strength and impact strength respectively in sisal composites because of water absorption.

Keywords:

• Fibres
• mechanical properties
• water absorption properties
• polymer matrix
• hand lay up method

Acknowledgement

The authors would like to thanks the Head of Mechanical Engineering Department and Head of Applied Mechanics Department Motilal Nehru National Institute of Technology Allahabad, India for their support in allowing us to perform the tests. The study is partially supported by Cumulative Professional Development Allowances (CPDA) for teachers of Motilal Nehru National Institute of Technology Allahabad, India.

Disclosure statement

No potential conflict of interest was reported by the authors.