Poly- -3-hydroxbutyrate

Poly(3-hydroxbutyric acid) [P(3HB)] is the most famous member in the family of PHAs. This homopolymer is an optically active polyester of (R)-specific units and has a high crystallinity up to 60 70%. The particular advantage is that P(3HB) is a thermoplastic and therefore can be processed by using the existing equipment. However the drawbacks are also serious... 

Fig. 1. Structure for poly-3-hydroxbutyrate and general structure for polyhydroxyalkanoate co-monomers.

Abate, R., Ballistreri, A., Montaudo, G., Giuffrida, M., and Impallomeni, G., Separation and Structural Characterization of Cyclic and Open Chain Oligomers Produced in the Partial Pyrolysis of Microbial Poly(Hydroxbutyrates), Macromolecules, 28, 7911, 1995. 

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