Effect of Sodium Benzoate on the Crystallization Behavior of Poly (3-Hydroxybutyrate-Co-4-Hydroxybutyrate)

Abstract

Poly (3-hydroxybutyrate-co-4-hydroxybutyrate) (P34HB), as the latest generation of biosynthesis and biodegradable Poly (β-hydroxyalkanoate) material, its mechanical performance is greatly improved while its application in industry is confined for the inadequate crystallization properties. The effect of sodium benzoate on P34HB’s crystallization behaviors and nucleation mechanism were investigated through differential scanning calorimetry (DSC) and Angle X-ray diffraction (WAXD). WAXD analysis indicated that the adding of sodium benzoate did not chang the crystalline morphology of P34HB. The analysis of the kinetic parameters including the activation energy (ΔEc) of the non-isothermal melt-crystallization were carried out, which demonstrated that both of the Mo crystallization rate parameter and the Kissinger activation energy value are found to be sharply dropped with the addition of sodium benzoate. Compared to pure P34HB, F(T) on 80 % crystallinity of P34HB with 0.25 phr sodium benzoate fell from 38.79 to 17.89, and ΔEc decreased from-63.1 KJ·mol-1 to-108.8 KJ·mol-1, which indicated that the application of sodium benzoate can obviously improve the crystallization rate of P34HB.