Modificação química do poli(3-hidroxibutirato) e preparação de membranas por eletrofiação para aplicação em biomateriais.

Abstract

Due to the increasing interest in biodegradable polymers, many studies have been conducted in order to obtain biodegradable polymers with improved mechanical and processing properties. The poly(3-hydroxybutyrate) (PHB) has been proposed as an ideal substitute for non-biodegradable polymers in commercial applications. However, its high crystallinity, thermal instability and high production costs are problems that have limited its commercialization. An alternative to modify it and improve its mechanical properties is through transesterification reactions with poly(εcaprolactone) (PCL), a synthetic polyester, also biodegradable and with high potential for use as a biomaterial. In this work, reactive extrusion of PHB/PCL blend was carried out, and the copolymer was characterized by solubility tests, differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), hydrogen (1 H-NMR) and carbon (13 C-NMR) nuclear magnetic resonance spectroscopies. The results indicated that PHB was modified, resulting in the copolymer PHB-co-PCL, showing lower crystallinity than the homopolymers. Viscosity measurements of PHB-co-PCL solutions were performed and electrospinning tests were carried out under different conditions. The scanning electron microscopy analysis (SEM) indicated the formation of smooth and uniform fibers, with average diameter between 900-1200 nm. Cell viability analysis confirmed that the material is not cytotoxic, favoring its applicability for the production of porous fiber mats in tissue engineering.