Optimization of polyethylene/polypropylene/alkali modified wheat straw composites for packaging application using RSM

Abstract

The objective of this research was to synthesize the optimized packaging film based on polyethylene (PE), polypropylene (PP) and alkali treated-wheat straw (WS) using central composite design (CCD). In this paper, effects of three independent factors viz. polyethylene (1.8–1.08 g), polypropylene (1.2–0.72 g), and alkali treated-wheat straw (0–1.2 g) on three dependent variables viz. tensile strength, elongation at break (%) and water vapor transmission rate (WVTR) of packaging film were investigated. Response surface methodology (RSM) provided the combination for an optimum film, which was 1.8 g of polyethylene, 1.2 g of polypropylene and 1.192 g of alkali treated-wheat straw giving 45.018 MPa tensile strength, 120% elongation limit and 51.740 g/m−2day−1 water vapor transmission rate, respectively for packaging application. The film prepared using the optimized results further characterized using several characterization techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), mechanical testing, contact angle, water vapor transmission rate and optical characteristics test. This result demonstrated the perfect use of treated-agro-waste in a polymer matrix for green packaging application. © 2019 Elsevier Ltd