The Compatibility of Poly(3-hydroxybutyrate-co-4-hydroxybutyrate) and Thermoplastic Polyurethane Blends

Thermoplastic polyurethane (TPU) has been used to toughen Poly (3-hydroxybutyrate-co-4-hydroxybutyrate) (P34HB) and increase its cold-resistance. The compatibility of P34HB/TPU blends was predicted by solubility parameter, then investigated by appearance and transparence, Dynamic Mechanical Analysis (DMA) and Scanning Electron Microscopy (SEM) analysis. The P34HB/TPU was found to be a partly compatible system. The appearance and transparence of P34HB/TPU blends were smooth and non-transparent. The DMA showed that the glass transition temperature of P34HB was decreased with the increase of TPU content. The SEM photos showed that the morphology of the P34HB/TPU blends were the sea island structure.