Structural dynamic properties of nonwoven composite mixtures based on ultrafine tissues of poly(3-hydroxybutyrate) with chitosan

Resumo

The structural dynamic parameters of ultrafine fibrous matrices of poly-3-hydroxybutyrate (PHB) and composite mixtures of PHB with chitosan were studied by differential scanning calorimetry, EPR spectroscopy, and scanning electron microscopy. The melting enthalpy of PHB fibers considerably increased when a small amount of chitosan was added. Amorphous regions with diverse morphology were found in the fibers under study. The dynamics of the TEMPO spin probe in these regions and its change in the fibers under the action of temperature, aqueous medium, and ozone was determined. The mechanism responsible for the effect of chitosan, temperature, and aggressive oxidating medium on the structure of ultrafine PHB fibers was suggested.