BACTERIAL PRODUCTION OF POLYESTERS BEARING PHENOXY GROUPS IN THE SIDE-CHAINS .1. PHENOXYPENTANOATE-CO-3-HYDROXY-9-PHENOXYNONANOATE) FROM PSEUDOMONAS-OLEOVORANS

The production of phenoxy-substituted poly(3-hydroxyalkanoates) (PHA) by Pseudomonas oleovorans was investigated. 11-Phenoxyundecanoic acid was used as a single carbon source for the bacterial culture. At the m aximum growth rate of the culture, the cells were isolated by centrifu gation. The cells were lyophylized and then extracted with trichlorome thane, yielding a comb-like copolyester. Methanolysis of this polyeste r was performed to characterize the incorporated hydroxyacids. This pr oved the polyester to be a copolymer: phenoxypentanoate-co-3-hydroxy-9 -phenoxynonanoate) (5; 6: 1 mole ratio). GPC measurements with polysty rene as standard indicated M(n)BAR values of approximately 76000 and a molecular weight distribution index of M(w)BAR/M(n)BAR = 2,3. The cop olyester showed a glass transition at 14-degrees-C.