Assessing Biodegradability of Pval/ Starch Blends in an Anaerobic Envinronment

Research was conducted into biological degradation of PVAL modified samples, mixed with starch in an anaerobic environment. The test of biodegradability was performed in an aqueous environment under anaerobic conditions with digested activated sludge from municipal wastewater treatment plant. Evalution of biodegradation was based on methane and carbon dioxide produced in the gas phase and TOC determination. Pure PVAL (Mowiol 5-88) was degraded from 7 %, degradation of WAXY starch was 74 %. PVA mixed samples, which contained 42 % WAXY starch, 32,8% PVA Mowiol 5-88 and 25,2 glycerine reached 66 – 74 % degradation , The blends which contained 21% WAXY starch, 62 % PVA Mowiol 5-88 and 17 % glycerine was found only 29 % degradation. There was demonstrated that the value of percentage anaerobic degradation was proportionate to the representation of biodegradable components in the sample.