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Sequence distribution in microbial poly(3-hydroxybutyrate-co-3-hydroxyvalerate) co-polyesters determined by NMR and MS.

Ema Zagar·Andrej Krzan·Grazyna Adamus·Marek Kowalczuk
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Abstract

The microstructure of bacterial poly(3-hydroxybutyrate-co-3-hydroxyvalerate) copolyesters (PHBV) as well as a mixture of two PHBV copolyesters of different comonomer composition and sequence distribution was studied by 13C NMR based on dyad and triad analysis and multistage electrospray ionization mass spectrometry (ESI-MSn). Both techniques gave results that were in good agreement for all investigated samples. The effect of microstructure on PHBV thermal properties was investigated from the melting behavior of samples. A PHBV copolyester with randomly distributed hydroxyvalerate units (12.0 mol % HV) showed a single melting peak, whereas samples with nonrandom composition distribution showed multiple melting peaks in their thermograms. Such complex melting behavior suggested that the 12.9 and 27.1 mol % PHBV copolyesters were actually blends of several copolymers with widely different comonomer-unit composition.

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Calorimetry, Differential ScanningCupriavidus necatorMagnetic Resonance SpectroscopyMolecular StructurePolyestersSpectrometry, Mass, Electrospray IonizationTemperatureJournal ArticleResearch Support, Non-U.S. Gov't

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Ema Zagar, Andrej Krzan, Grazyna Adamus, Marek Kowalczuk. 2006. Sequence distribution in microbial poly(3-hydroxybutyrate-co-3-hydroxyvalerate) co-polyesters determined by NMR and MS.. https://doi.org/10.1021/bm060201g

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