Abstract
Bioplastics is a rapidly emerging topic, to meet technical constraints they, however, often required substantial modifications. The modification of grafting of natural polymers, such as cellulose, is one of the most promising ways to get reliable bioplastics to the market. For the better control of properties and further optimized design of these materials the characterization of grafts is mandatory. This, however, can not be achieved via traditional methods, due to different reactivity of natural and synthetic polymers.
An assay based on a catalytic specificity and robustness of cellulolytic enzymes was tested for the selective hydrolysis of the cellulosic matrix of a withdrawn sample and the recovery of the grafts in the organic phase. Among three tested commercial cellulases, A. niger cellulase is the most efficient in a biphasic media containing up to 75 % of chloroform. Thus, the sample containing up to 40 g/L of cellulose- based material was transformed in 4 hours by 10 g/L overall enzyme, with no damage for the polyester grafts.
A novel, specific, easy to manage and robust assay for the characterization of grafted cellulosic materials is reported in this research report. Chemically weaker, the ester bond of the polyester grafts is, however, preserved, whereas the ether cellulosic bond is specifically cut by the enzyme.
