The Laboratory on Structure and Properties of Polymers (Prof. M. Evstatiev, Assoc. Prof. E. Vassileva) works on polymer composites and blends, solid state reactions in condensation polymers (basics and commercial application), physical and chemical modification of polymers, nano- and macro composites, biodegradable polymers and polymer materials for medical applications. The Laboratory has developed many cooperations with international and national partners and successfully implemented many international and national projects. Under the present topic the Laboratory will continue the investigations biodegradable materials for packing. Previous research activities in this direction [,] included development of environmentally-friendly materials based on gelatins (by-products from the food industry). The biodegradability of these materials was followed under simulated and natural conditions. The mechanical performance of these biomaterials has been improved by using a special orientation technique for polymers with semi-rigid chains as well by an appropriate modification (chemical, thermal, etc.).
 R. D. Patil, J. E. Mark, P. G. Dalev, E. Vassileva, S. Fakirov, “Solubilization and Biodegradation of Crosslinked Gelatins by Alkaline Proteinase” Polymer-Plastic Tech. & Eng. 34(9), 683-697 (2000).
 P. G. Dalev, R. D. Patil , J. E. Mark,E. Vassileva, S. Fakirov, “Biodegradation of Chemically-Modified Gelatin Films in Soil” J. Appl. Polym. Sci., 78, 1341 (2000).