Modification of poly(3-hydroxybutyrate) with mixture of methyl esters of fatty acids obtained by transesterification of waste edible oils : master thesis

Smjesi metilnih estera masnih kiselina određene su fizikalne značajke: gustoća i kinematička viskoznost, a primjenom GC-MS analize određen je njezin sastav. Modifikacija poli(3-hidroksibutirata) (PHB) je provedena dodatkom različitih udjela smjese metilnih estera masnih kiselina (SME) s ciljem poboljšavanja mehaničkih i toplinskih svojstava PHB-a i njegove šire komercijalne primjene. Uspješno su pripravljeni filmovi mješavina PHB/SME u kloroformu s 10 mas.%, 15 mas.%, 20 mas.%, 25 mas.% i 30 mas.% SME metodom izlijevanja filma iz otopine. Diferencijalnom pretražnom kalorimetrijom određeni su fazni prijelazi PHB-a u mješavinama. Utvrđeno je da se, dodatkom SME, staklište PHB-a snižava, a stupanj kristalnosti raste. Primjenom FTIR analize ispitan je utjecaj SME na PHB.The physical characteristics of the fatty acid methyl ester mixture were determined: density and kinematic viscosity, and its composition was determined using GC-MS analysis. The modification of poly(3-hydroxybutyrate) (PHB) was carried out by adding different proportions of a mixture of fatty acid methyl esters (FAME) with the aim of improving the mechanical and thermal properties of PHB and its wider commercial application. PHB/FAME films of mixtures were successfully prepared in chloroform with 10 mas.%, 15 mas.%, 20 mas.%, 25 mas.% and 30 mas.% FAME by casting the film from the solution. The phase transitions of PHB in the mixtures were determined using differential scanning calorimetry. It was found that FAME addition lowers the glass transition temperature but increases the melting temperature of PHB. The influence of FAME on PHB was also examined using Fourier transform infrared spectroscopy