Degradation and Moisture Absorption Study of Potato-starch Linear Low Density Polyethylene Blend

Composite of linear low density polyethylene (LLDPE) and potato-starch was produced and subjected to degradation studies with the agencies of enzymes, exposure to weather and immersion in water. Enzymatic hydrolysis degraded the matrix to an extent greater than 40% loss in strength and about 20% loss in elongation–at-break within just 10 days. These deteriorations correlated with the decrease in weight. Immersion in water indicated increased uptakes with starch content which also corresponded with decrease in tensile strength and elongation-at-break with time of immersion. Exposure to weather completely reduced the composites to easily crushable masses the extent of which was also related to starch content. Micrographs of the tested samples showed that the weak points are the starch sections which after being eaten up by microorganisms or swollen up by moisture lend the matrix more amenable to further degradation.