*Article* **Study of Hybrid Modification with Humic Acids of Environmentally Safe Biodegradable Hydrogel Films Based on Hydroxypropyl Methylcellulose**

**Denis Miroshnichenko 1,\* , Katerina Lebedeva <sup>2</sup> , Anna Cherkashina <sup>2</sup> , Vladimir Lebedev <sup>2</sup> , Oleksandr Tsereniuk <sup>3</sup> and Natalia Krygina <sup>3</sup>**


**Abstract:** The possibility of increasing the complexity of the operational properties of environmentally safe biodegradable polymer hydrogel materials based on hydroxypropyl methylcellulose due to modification by humic acids from lignite is considered. As a result of this research, environmentally safe hybrid hydrogel films with antibacterial properties were received. In the framework of physicochemical studies, it was determined by IR spectroscopy that hydroxypropyl methylcellulose modified with humic acids hybridmaterials are received by the mechanism of matrix synthesis, which is accompanied by hydroxypropyl methylcellulose crosslinking through multipoint interaction with the carboxyl group of humic acids. Regularities in terms of changes in water absorption, gelation time, and mold emergence time regarding the environmentally safe biodegradable polymer hydrogel materials based on hydroxypropyl methylcellulose depending on the humic acid content were revealed. It was established that the optimal humic acid content in environmentally safe biodegradable hydrogel films with bactericidal properties based on hydroxypropyl methylcellulose is 15% by mass. It was also established that the hybrid modification of hydroxypropyl methylcellulose with humic acids allows them to preserve their biodegradation properties while giving them antibacterial properties. The environmentally safe biodegradable hydrogel films with bactericidal properties based on hydroxypropyl methylcellulose and humic acids are superior in their operational characteristics to known similar biodegradable hydrogel films based on natural biopolymers.

**Keywords:** environmentally safe; biodegradable; hydrogel films; hydroxypropyl methylcellulose; bactericidal properties; humic acids; hybrid; modification
