Effect of the Biodegradable Compounds Composition with Monoglycerides on Mechanical Properties

Abstract

The purpose of this work is to improve the production technology of biodegradable hybrid compositions based on low-density polyethylene with thermoplastic starch and new plasticizer–distilled monoglyceride and determination of the composition effect on mechanical properties. Starch was plasticized with a mixture of glycerol and distilled monoglycerides, instead of the known sorbitol. This article describes methods for producing biodegradable hybrid composite films based on polyethylene and thermoplastic starches (corn, pea and rice) with a mass ratio of components, respectively, 40:60÷60:40 and their mechanical properties. Properties and structure of composite films are studied using test methods, rheological parameters, optical microscopy, and differential scanning calorimetry. The advantages of using monoglycerides as a plasticizer in thermoplastic starch/ polyethylene compositions have been demonstrated. Composites obtained using distilled monoglycerides and thermoplastic corn, pea and rice starch have been characterized by 62-81% higher values of critical stress and 62-93% elongation at rupture, compared with BHC containing sorbitol. The thickness of biodegradable hybrid composite films with monoglycerides is 55-86% less than that of films containing sorbitol in composition of thermoplastic starch. Higher elongation values at rupture and lower film thickness will ensure more effective destruction in environment and more cost-efficient use in packaging.