Bacterial Polyesters: Microbial Polyhydroxyalkanoates and Nonnatural Polyesters (Adv. Mater. 35/2020)

So Young Choi; In Jin Cho; Youngjoon Lee; Yeo‐Jin Kim; Kyung‐Jin Kim; Sang Yup Lee

doi:10.1002/adma.202070264

Bacterial polyesters grafted with poly(ethylene glycol): Behaviour in aqueous media

Polymer Degradation and Stability ◽

10.1016/j.polymdegradstab.2007.03.001 ◽

2007 ◽

Vol 92 (7) ◽

pp. 1384-1392 ◽

Cited By ~ 16

Author(s):

Sandra Domenek ◽

Valérie Langlois ◽

Estelle Renard

Keyword(s):

Ethylene Glycol ◽

Aqueous Media ◽

Poly Ethylene Glycol ◽

Poly Ethylene ◽

Bacterial Polyesters

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Pyrolysis of bacterial polyalkanoates

Canadian Journal of Chemistry ◽

10.1139/v81-334 ◽

1981 ◽

Vol 59 (15) ◽

pp. 2306-2313 ◽

Cited By ~ 99

Author(s):

Hiromichi Morikawa ◽

Robert H. Marchessault

Keyword(s):

Crotonic Acid ◽

Bacterial Cells ◽

Nmr Analysis ◽

Pyrolysis Products ◽

Bacterial Cultures ◽

Pyrolysis Method ◽

Bacterial Polyesters

Pyrolysis products from bacterial polyesters, poly-β-hydroxybutyrate (PHB), and from a heteropolyester (β-hydroxyvalerate and β-hydroxybutyrate) were identified. Different physical forms of PHB were studied: PHB purified by dissolution in chloroform, native granules of PHB, and PHB in bacterial cells. The products were characterized by gc, ms, and nmr analysis. The yield of crotonic acid obtained by the pyrolysis of purified PHB was 60 to 65%. Pyrolysis of PHB native granules yielded crotonic acid as well as oligomers of PHB with a terminal crotonate. Upon direct pyrolysis of dry bacterial cells, the yield of crotonic acid was 20 to 25% of the PHB in the cells. From the heteropolymer, 2-pentenoic acid and terminally unsaturated oligomers of polyhydroxyvalerate were obtained. The usefulness of the pyrolysis method for obtaining vinyl compounds from bacterial cultures containing polyalkanoates is discussed.

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Bacterial Polyesters and Their Models Obtained by Ring-Opening Polymerization of β-Lactones

Models of Biopolymers by Ring-Opening Polymerization ◽

10.1201/9781351074711-3 ◽

2018 ◽

pp. 235-290

Author(s):

Alain Le Borgne ◽

Nicolas Spassky

Keyword(s):

Ring Opening ◽

Ring Opening Polymerization ◽

Bacterial Polyesters

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Manufacturing and Properties of Binary Blend from Bacterial Polyester Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) and Poly(caprolactone) with Improved Toughness

Polymers ◽

10.3390/polym12051118 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1118

Author(s):

Juan Ivorra-Martinez ◽

Isabel Verdu ◽

Octavio Fenollar ◽

Lourdes Sanchez-Nacher ◽

Rafael Balart ◽

...

Keyword(s):

Thermal Analysis ◽

Impact Resistance ◽

Precise Determination ◽

Scanning Calorimetry ◽

Binary Blend ◽

Two Phases ◽

Almost All ◽

New Applications ◽

Poly Caprolactone ◽

Bacterial Polyesters

Polyhydroxyalkanoates (PHAs) represent a promising group of bacterial polyesters for new applications. Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is a very promising bacterial polyester with potential uses in the packaging industry; nevertheless, as with many (almost all) bacterial polyesters, PHBH undergoes secondary crystallization (aging) which leads to an embrittlement. To overcome or minimize this, in the present work a flexible petroleum-derived polyester, namely poly(ε-caprolactone), was used to obtain PHBH/PCL blends with different compositions (from 0 to 40 PCL wt %) using extrusion followed by injection moulding. The thermal analysis of the binary blends was studied by means of differential scanning calorimetry (DSC) and thermogravimetry (TGA). Both TGA and DSC revealed immiscibility between PHBH and PCL. Mechanical dynamic thermal analysis (DMTA) allowed a precise determination of the glass transition temperatures (Tg) as a function of the blend composition. By means of field emission scanning electron microscopy (FESEM), an internal structure formed by two phases was observed, with a PHBH-rich matrix phase and a finely dispersed PCL-rich phase. These results confirmed the immiscibility between these two biopolymers. However, the mechanical properties obtained through tensile and Charpy tests, indicated that the addition of PCL to PHBH considerably improved toughness. PHBH/PCL blends containing 40 PCL wt % offered an impact resistance double that of neat PHBH. PCL addition also contributed to a decrease in brittleness and an improvement in toughness and some other ductile properties. As expected, an increase in ductile properties resulted in a decrease in some mechanical resistant properties, e.g., the modulus and the strength (in tensile and flexural conditions) decreased with increasing wt % PCL in PHBH/PCL blends.

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