Effect of additives on the melt rheology and thermal degradation of poly[(R)-3-hydroxybutyric acid]
Thermal degradation of poly[(R)−3-hydroxybutyric acid] (PHB) during melt mixing results in random chain scission that produces shorter polymer chains containing crotonic and carboxyl end groups. One way of preventing this serious reduction of molar mass is to add agents that react with at least two of the newly generated end groups. Different types of commercially available additives known to reac