Using the method of pyrolytic mass spectrometry in the study of biodegradable polymeric materials
Authors:   Institute of Macromolecular Chemistry NAS of Ukraine, 48, Kharkivske shose, Kyiv, 02160, Ukraine, Boyko V.V. , Riabov S.V. ,   Institute of Macromolecular Chemistry NAS of Ukraine, 48, Kharkivske shose, Kyiv, 02160, Ukraine, Kobrina L.V. ,   Institute of Macromolecular Chemistry NAS of Ukraine, 48, Kharkivske shose, Kyiv, 02160, Ukraine, Dmitrieva T.V. ,   Institute of Macromolecular Chemistry NAS of Ukraine, 48, Kharkivske shose, Kyiv, 02160, Ukraine, Bortnitsky V.I. ,   Institute of Macromolecular Chemistry NAS of Ukraine, 48, Kharkivske shose, Kyiv, 02160, Ukraine
Published: March 2021

The results of pyrolytic mass spectrometry studies of biodegradable polymeric materials based on polyolefins and segmented polyurethanes with various functional additives are summarized. The structure and composition of initial and after exposure in soil, climate chamber and after exposure to microorganisms (bacteria, yeast) composites are characterized. In the research presented, influence of acetates and complexonates of metals, including cobalt, copper and zinc, on the structural changes in the high pressure polyethylene (HPPE) occurring under the impact of factors such as temperature, humidity and UV-radiation is investigated. It was established, that samples of HPPE, modified by cobalt acetate and cobalt and copper complexonates are responsive and most sensitive to the action of above-mentioned physical factors. Investigation of a segmented polyurethanes (SPU) of a different chemical structure influenced by a factors, modeling of the environmental conditions was conducted. It was shown using pyrolytic mass-spectrometry method and monitoring of samples’ weight loss that under the influence of above-mentioned environmental factors in the SPU occurs processes, resulting to changing its micro heterogeneous structure. It is established that SPU having ester links in its structure and being exposured in soil for 120 days is predominantly attacked by microorganisms, then the main active factor appears to be soil’ pH value – after 300 days in soil with alkaline or acid solution SPU sample decomposes into a separate fragments. Features of the chemical structure of urethane polymers synthesized on the base of hydroxylated rapeseed oil (polyol) were examined. Analysis of the results showed that the macromolecular compounds obtained are segmented polyurethanes which thermal degradation occurs in two stages: hard blocks are destroyed at the first stage, while polyol part (soft blocks) decomposes at the second stage, allowing to identify the temperature area of polymer destruction and thus its temperature region of operation. It is shown that the most suitable from the viewpoint of environmental friendly is polyurethane composition containing more than 50% of polyol. Thermal mass-spectrometry (TMS) has been employed to investigate processes of thermal destruction of segmented polyurethane and it’s compositions filled by polysaccharides: starch, dextrin, chitosan. The features of thermal destruction for segmented polyurethane and related compositions before and after their storage in a soil have been determined. Application TMS is shown to permit the processes of biodegradation of polymeric materials to investigate.