Role of extracted nanosilica from rice husk on the structure, property and biodegradability of low density polyethylene/starch biodegradable film

Abstract

Starch blended low‐density polyethylene (LDPE) has been extensively used to produce packaging film, but it has very low mechanical properties. This work emphasises the extraction of nanosilica from rice husk as a property‐enhancing filler for producing high‐quality packaging material. Nanosilica (200 nm) was obtained by chemical treatment followed by further size reduction through cryomill. The obtained nanomaterial was found to have a high surface area (189.64 m2/g) and pore volume (.462 cc/g) with high compatibility with the other materials in the matrix. The SEM and TEM analysis indicates the uniformity in particle size of the nanomaterial with an agglomerating tendency. The X‐ray diffractometer (XRD) and fourier transform infrared spectroscopy (FTIR) analysis reveals that the obtained material is amorphous in nature. The nanomaterial is dispersed in various proportions in LDPE/starch matrix, and it is observed that the highest tensile strength (9.62 MPa) can be obtained at 1.5% nanosilica content in the matrix. A continuous increase in Young's modulus and stiffness from 372.3 to 440.12 MPa and 20 243.2 to 28 559.42 N/m, respectively, when 1.5% of nanosilica is dispersed in the biodegradable matrix. Garden soil was a better degrading medium for the sample containing 20% of starch with weight loss of 10.32% and reduction of tensile strength and tear strength values to 5.987 MPa and 99.165 N/mm respectively, in 1 year.