Kenaf–polypropylene composites: Effect of amphiphilic coupling agent on surface properties of fibres and composites

This paper presents an experimental study on the use of zein as a coupling agent in natural fibre composites. Kenaf nonwovens were treated with zein coupling agent, which is a protein extracted from corn. The surface characteristics of untreated and chemically treated kenaf fibres were investigated by FTIR, zeta-potential measurements and Energy Dispersive X-ray Spectroscopy (EDS) mapping. Composites were prepared by compression moulding using nonwovens treated with zein solution. The reinforcing properties of the chemically treated composites were compared with that of untreated composites. The viscoelastic and thermal properties of composites were also determined. Composites containing chemically modified kenaf fibres were found to possess improved mechanical and viscoelastic properties. EDS mapping studies revealed the presence of surface functionalities on treated kenaf fibres.