However, PLA has higher activation energy showing higher degradation kinetics. This observation indicates that the degradation rate depends on temperature. A blend of PLA and PCL showed lower thermal stabilities than both polymers. However, the thermal stability can be improved by adding TiO2 nanoparticles . TiO2 NPs also improved the thermal stability of PLA/poly(hydroxybutyrate-co-valerate) (PHBV) .