The effects of cellulosic fibers on the thermal, morphological, structural properties of plyhydroxybutyrate biyopolymer method

The purpose of this study is to investigate the effects cellulosic fibers such as cellulose fibers (HT) obtained from heat-treated beechwood, cellulose fibers (UT) obtained from un-treated wood, bacterial cellulose (BC), cotton (P), on the thermal (TGA / DTG and DTA), morphological (SEM) and structural (FTIR and XRD) properties of polyhydroxybutyrate (PHB) biopolymers. In this study, PHB matrix was mixed with diffirent cellulosic fibers by solvent method. Chloroform was used to dissolve the PHB and the mixture was supplied using ultrasonic and magnetic stirrers. The thermal properties of the obtained biocomposite films were determined by thermogravimetric analysis (TGA / DTG) and derivative thermal analysis (DTA), morphological characterization by electron microscopy (SEM), x-ray diffraction analysis and structural characterization by FTIR. According to the TGA curves, the highest results for T10% and T50% of PHB biocomposites was obtained at 260,5 °C for UT and 286,4 °C for HT. In contrast, the highest value for T 85% was found to be 383,6 °C for P. According to DTG curves, the highest value was determined at 288,7 °C for HT. DTA analysis also showed that Tg, Tm and enthalpy values of pure PHB and PHB composites were increased. When SEM images are examined, a porous structure (formation of a voided structure) is observed in PHB biocomposites. In XRD analysis of PHB biocomposites, it was observed that other samples showed similar structures except for the biocomposite with P. XRD analysis also showed that PHB biopolymer showed 6 main peak formation. Main peaks of pure PHB and PHB biocomposites were found to be at similar points of 17,63°, 22,83°, 25,30°, 26,15°, 29,65° and 42,18°. According to the FTIR analysis, it was found that there was no different formation between the composites and the structure was generally similar.