P-Hydroxyoctanoate

Dubief, D. Samain, E. Dufresne, A. Polyssaccharide microcrystals reinforced amorphous poly(P-hydroxyoctanoate) nanocomposite material. Macromolecules 1999, 32 (18), 5765-5771. 

Poly(P-hydroxyoctanoate), polyvinylchloride, waterborne epoxy, natural rubber (NR), and polyvinyl acetate (PVAc) were also used as matrices. 

Lageveen et al. [41] showed that the monomer composition of aliphatic saturated poly(3HAMCL) produced by P. oleovorans is depended on the type of n-alkane used. It appeared that the n-alkanes were degraded by the subsequent removal of C2-units and it was therefore proposed that the /1-oxidation pathway was involved in poly(3HAMCL) biosynthesis. Preusting et al. [42] confirmed these results but also showed that with hexane as substrate some 3-hydroxyoctanoate and 3-hydroxydecanoate were produced, indicating that additional pathways were involved in poly(3HAMCL) biosynthesis (Table 1). 

It is interesting to investigate effects of long side chains on the molecular dynamics and related physical properties of poly(hydroxyalkanoic acid)s. The poly(hydroxyalkanoic acid)s with longer side chains, such as poly(3-hydroxyoctanoic acid) [P(3HO)], have quite different mechanical properties from P(3HB) and P(3HB-co-3HV), being thermal elastmers with low glass transition temperatures ranging from -25 to — 40°C [88] and a much lower crystallinity of about 25-33% [89]. 

In order to determine which one of the two routes is responsible for the formation of 3-hydroxydecanoate constituents, we cultivated P. putida on a combination of octanoate and [2- C] acetate. The resulting PHA consisted of the monomers 3-hydroxyhexanoate (8%), 3-hydroxyoctanoate (89%) and 3-hydroxydecanoate (3%). The labeling pattern of this polymer gives information on the origin of the monomers. 

Halogenated PHAs. Several halogenated PHAs were obtained when certain bacterial species (P. oleovorans, P. putida) were cultured in media containing chlorinated, brominated or fluorinated compounds. A copolyester containing (R)-3-hydroxyoctanoate, (P)-3-hydroxy-8-chlorooctanoate, (P)-3-hydroxyhexanoate and (/ )-3-hydroxy-6-chlorohexanoate was synthesized when a culture of P. oleovorans was fed with octane and 1-chlorooctane as carbon sources (Doi and Abe 1990). Additionally, PHAs containing brominated monomers were produced by P. oleovorans when it was cultured in media containing mixtures of n-alkanoic acids (octanoic and nonanoic acids) and co-bromoalkanoic acids (Kim et al. 1992). 

Timbart L, Renard E, Langlois V, Guerin P (2004) Novel biodegradable copolyesters containing blocks of poly(3-hydroxyoctanoate) and poly(8-caprolactone) synthesis and characterization. Macromol Biosd 4 1014—1020... 

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