Plasticizer Mixing Improved Regenerated Cellulose Films as an Alternative to Plastics
Pauliina Ahokas, Vesa Kunnari, Johanna Majoinen, Ali Harlin, Mikko Mäkelä
Abstract
Plasticizers are widely used to improve the elasticity of regenerated cellulose films, but academic research has thus far ignored the possibility of plasticizer mixing. We studied the effects of glycerol, sorbitol, and maltitol on film properties based on a systematic design for mixture experiments and determined regression models to correlate the mixture composition with film properties. Our results showed that plasticizer mixing enabled us to control film tensile strength and water vapor and oxygen permeabilities, which are key indicators for evaluating film efficacy in barrier packaging applications. Our films showed lower water vapor and oxygen permeabilities than commercial uncoated cellophane films and could potentially provide a renewable alternative to conventional polyolefin films with further improvements. These results are important and they indicate that plasticizer mixing provides a novel and simple methodology to improve regenerated cellulose films to meet the increasing demand for alternatives to conventional plastics in packaging and other applications.