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This paper focuses on the study of novel blends based on poly(3-hydroxybutyrate) (PHB) and polymers with different hydrophilicity [polyethylene (PELD) and polyamide resin (PA548)]. Polymer blends were produced from fi ve ratios of PHB/PELD in an effort to regulate the resistance to hydrolysis or (bio)degradation through the control of water permeability. The relation between the water transport and morphology (TEM data) shows the impact of polymer component ratio on the regulating water fl ux in hydrophobic matrix. To elucidate the role of hydrophilicity of the second component 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 ratio 1:1. The complex of techniques including DCS and Fourier Transform Infrared (FTIR)-imaging (on the scale of temperature) indicates an interaction between PHB and PA in the temperature ranges of crystallization and melting. The general approach based on Flory-Huggins equation is presented as a way to choose pairs of compatible or partly compatible polymers. Blending PHB with PA could be a simple and effective method to design new matrices for drug delivery, while the same procedure applied to PHB-PELD system with better resistance again, hydrolysis and lower cost than parental PHB could be used as novel bioerodible packaging materials.

A quick method for assessing elastomer-to-shungite bond strength is presented. An Instron 3365 tensile testing machine was used to measure the force needed to peel away a cotton strip impregnated with a rubber solution in CCl4 from the surface of shungite sheets. The rubbers included butyl rubber (BR), nitrile butadiene rubber (SKN-18), polyisoprene (SKI-3), a copolymer of ethylene and vinyl acetate (CEVA), polychloroprene (PC), chlorosulphonated polyethylene (CSPE), and chlorinated butyl rubber (CBR). The nature of the obtained results depends on elastomer functionality. Smooth curves of the dependence of the measured stress on the distance between the clamps of the tensile testing machine were obtained for elastomers not having functional groups interacting with the shungite, e.g. for BR; on the curves for elastomers interacting with the shungite, e.g. for PC, a series of peaks was observed on the curves. The obtained results make it possible to predict the strength of elastomer composite materials containing shungite.