The development of polymer composites using recycled or recyclable polymers is very actively pursued due to threats of uncertain petroleum supply in the near future and environmental concerns. Natural fibre composites are proposed to substitute synthetic fibre composites due to several advantages such as biodegradability, renewability, recyclability, abundant, permeability, corrosion resistance, high degree of flexibility, hygroscopicity, non-toxicity, capability of giving up moisture, no release of substances harmful for health, non-irritation to the skin, no allergic effect, competitive mechanical properties, reduced energy consumption, less abrasiveness to processing equipment, and minimum waste disposal problems 1–27. However, the major drawback of natural fibres based composites is the incompatibility between the hydrophilic natural fibres and the hydrophobic polymeric matrices. Among the large amount agricultural crop residues, only a small quantity of the residues was applied as household fuel or fertilizer and the rest which is the major portion of the residues is burned in the field.
As a result, it gives a negative effect on the environment due to the air pollution 28. The vital alternative to solve this problem is to use the agriculture residues as reinforcement in the development of polymer composites 29. The current concern over the environment and greenhouse gas emissions, natural fibres are increasingly being considered as an environmentally friendly substitute for synthetic fibres in the reinforcement of polymer based composites 30–32. Nowadays, plant fibres are the most commonly used natural fibres for polymer composites and the reinforcing these fibres with polymers is to enhance the mechanical properties of the materials 2,33. Among the many different types of natural resources, kenaf plants have been extensively exploited over the past few years 34,35 which is a particularly attractive option due to its rapid growth over a wide range of climatic conditions and its consequent low cost 36.