Title: The effect of functional additives on the structure and properties of PHB based nanofibers

Abstract

Highly porous polymer carriers of biologically active substances are currently widely used in biology and medicine as long-acting matrices, matrices for cell engineering, antibacterial therapeutic systems, matrices for controlled release of drugs, etc. The study of the design possibilities and the directed influence on the structure and properties of semi-crystalline polymers of natural origin using various additives and modifiers is an area of a great interest in our days.Thus, various functional additives, including porphyrin complexes with various metals, are used to create biocompatible antibacterial polymer systems. The aim of the work was to study the effects of zinc (ZnTPP), manganese (MnClTPP) and iron (FeClTPP) tetraphenylporphyrin complexes on the supramolecular structure and properties of the electrospun fibers based on the biopolymer polyhydroxybutyrate (PHB). Various methods were used for studying the structure and properties of the materials, including DSC, EPR, TGA, mechanical analysis and microscopy methods. In the work, significant differences in the structure of PHB with 1-5 wt. % of the FeClTPP, ZnTPP, and MnClTPP complexes were found. The influence of the complexes on the morphology, mechanical and diffusion properties, the kinetics of biodegradation of non-woven materials was established. Special attention was paid to the studying of the antibacterial activity and the rate of biodegradation of the obtained materials. An approach for solving the actual problem of the formation of fibers of certain morphology with a set of necessary operational properties is proposed.