polyhydroxybutyrate

Porous osteoplastic composites using polyhydroxybutyrate as a binder and hydroxyapatite (HA) as a reinforcing component were obtained by press molding. To evaluate the effect of HA particles on the structure and properties of the composites, the amount of filler was varied from 0 to 50 wt%. %. It was found that the addition of HA to the polymer matrix causes a decrease in the mechanical strength of the resulting composites due to the formation of discontinuities in the matrix caused by poor interaction between the matrix and filler particles.

The changes in the crystal structure of polyhydroxybutyrate, polylactide, and their blends during biodegradation under the influence of bacteria and fungi were studied using X-ray diffraction analysis. It was found that microorganisms induce structural transformations in polymers, which occur without significant mass loss of the samples. X-ray diffraction analysis revealed that biodegradation is a complex multifactorial process that depends on the nature of the polymer and microorganisms and is characterized by microstructural changes in the film samples. 

The biosynthesis of cellular polymers of Azotobacter vinelandii N-15 strain using molasses as a carbon source has been optimized. The highest yield of polymer (25.8 % of cell mass) was obtained on a nutrient medium with a molasses concentration of 50 g/l. Using TL-chromatography and IR-spectroscopy the obtained product was identified as polyhydroxybutyrate (PHB), and its properties were investigated. The wetting contact angle was used to characterize the biopolymer film surface properties.

the water transport and morphology (TEM data) shows the impact of polymer component ratio on the regulating water flux in a hydrophobic matrix. To elucidate the role of hydrophilicity of the second component presented in the PHB blends, we studied the PHB/PA blends where PA is the polyamide resin composed of statistical copolymer of hexamethyleneadipinate and ε-caprolactam in the ratio of 1:1. The complex of techniques including DCS and FTIR-imaging (for T-scale) demonstrates the interaction between PHB and PA in the temperature ranges of crystallization and melting.