Property modellingModel-free non-isothermal crystallization kinetics of poly(3-hydoxybutyrate) filled with carbon black

Non-isothermal crystallization kinetics of poly(3-hydoxybutyrate) (PHB) filled with different amounts of carbon black (CB) was investigated by differential scanning calorimetry for both, the cold and melt crystallization process. The Friedman method was applied to describe the crystallization kinetics and to determine the conversion dependent apparent activation energies. It was found that carbon black acts as a nucleating agent, reducing the apparent activation energy for the crystallization onset significantly, and thus greatly facilitating the phase transformation. Considering PHB-CB compounds with CB content ≥5%, the kinetic data can only be interpreted assuming a complex multi-step crystallization mechanism, where the exact role of CB is unclear.