Biodegradability assessment of starch/glycerol foam and poly(butylene adipate-co-terephthalate)/starch film by respirometric tests

The objectives of this work were to determine the biodegradability of starch/glycerol foam and of poly(butylene-adipate-co-terephthalate) (PBAT)/starch film using respirometric methods and also to compare these results with conventional polymers – expanded polystyrene and low-density polyethylene. A matured organic compost was utilized as inoculum and sucrose was used as positive reference material. Biodegradation efficiencies (BE) after 47 days were: 35% for sucrose; 34% for starch/glycerol; and 38% for PBAT/starch. Starch/glycerol and PBAT/starch presented BE statistically equal to sucrose, whilst both the conventional packaging used were not degraded (p> 0.05). Infrared spectroscopy and thermogravimetric analyses showed that the microbiota rather degraded the starch over the PBAT in the PBAT/starch blend, and also that some starch remained intact in the internal polymeric matrix. This study verified that starch/glycerol foam and PBAT/starch film are highly biodegradable materials and may then be used to enhance the biodegradability of some products such as disposable trays and supermarket bags.

Quantification and biodegradability assessment of meso-2,3-dimercaptosuccinic acid adsorbed on iron oxide nanoparticles

An analytical method was developed to quantify the amount of free and nanoparticle-bound dimercaptosuccinic acid to address the question whether or not the coating material is biodegradable.