Processability of PVC plastisols containing a polyhydroxybutyrate-polyhydroxyvalerate copolymer



Plastisols based on polyvinyl chloride (PVC) can be processed by different techniques; their processability markedly depends on their flow properties and gelation/fusion processes. Classically, PVC has been the only polymer present in plastisol formulations. The present work explored the possibility of adding polyhydroxyalkanoates (PHAs), a type of biopolymer that, according to previous work, exhibits a good miscibility with PVC processed by other techniques (internal mixer and compression molding). The influence of PHA particles on flow properties, gelation-fusion processes, tensile strength, hardness, and processability by rotomolding was evaluated. Although the biopolymer markedly increased the viscosity of PVC plastisols and caused a decrease in tensile strength in processed specimens, formulations including 20% by weight of biopolymer presented a good thickness distribution in rotomolded items, an elongation at break of around 300%, and an ultimate tensile strength of around 6–7 MPa. J. VINYL ADDIT. TECHNOL.,, 2012. © 2012 Society of Plastics Engineers