Partial Depolymerization and Solubilization of Poly[(R)-3-hydroxybutanoate] (PHB) and Its Copolymer with (R)-3-Hydroxyvalerate (BIOPOL®) by Treatment with Li-Amides/LiCl in Tetrahydrofuran at Low Temperature

Abstract

The biopolymers PHB and PHB/PHV (mol. weight > 7·105 g·mol^-1) from fermentations of certain lot numbers or PHB samples which had previously been precipitated from dichloroethane solution can be dissolved by treatment with excess lithium-di-isopropylamide in LiCl-containing tetrahydrofuran. The samples recovered from these solutions in good yields have molecular weights of 1000–5000 g·mol^-1.