Thermal, rheological, mechanical and morphological behavior of HDPE/chitosan blend

A peroxide-initiated melt compounding technique was used to graft and crosslink the high density polyethylene/chitosan blend using vinyl triethoxysilane. Different percentage of chitosan (up to maximum of 35%) was added in HDPE/chitosan blends. The physical and functional properties of the crosslinked HDPE/chitosan blends were investigated and compared with its non-crosslinked congener. IR spectrum of crosslinked blend confirmed the presence of Si–O–Si and Si–O–C absorption peaks at 1020 cm−1 and 1105 cm−1. Increased gel content was obtained with increasing chitosan loading whereas percentage crystallinity was decreased. Rheological study of crosslinked blends showed linear viscoelastic behavior with high complex viscosity and dynamic shear storage modulus. Tensile strength of crosslinked HDPE was 9.3 MPa and it was increased by threefold to 27.4 MPa in crosslinked HDPE/chitosan blends containing 35% chitosan contents. Similarly lower deformation was observed in crosslinked blends under static load. Scanning electron microscopy revealed good adhesion between matrix–filler interphase.