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Perspectives to produce positively or negatively charged polyhydroxyalkanoic acids
1Department of Chemistry, University of Alabama in Huntsville, 301 Sparkman Dr., Huntsville, AL 35899, USA. cscholz@chemistry.uah.edu
Applied Microbiology and Biotechnology
|August 20, 2010
Summary
This study explores synthesizing charged poly(β-hydroxyalkanoates) (PHAs) via polymer-analogous reactions. Functionalized PHAs, particularly those with vinyl groups, serve as precursors for creating PHA polyanions and polycations.
Area of Science:
- Polymer Chemistry
- Biotechnology
- Materials Science
Background:
- Poly(β-hydroxyalkanoates) (PHAs) are bacterial polyesters with diverse applications.
- Direct microbial fermentation yields functionalized PHAs but not charged variants.
- Charged PHAs require post-polymerization modification through polymer-analogous reactions.
Purpose of the Study:
- To review methods for producing charged poly(β-hydroxyalkanoates) (PHAs).
- To identify suitable PHA precursors for synthesizing charged polymers.
- To outline strategies for creating PHA polyanions and polycations.
Main Methods:
- Utilizing functionalized bacterial polyesters as precursors.
- Employing polymer-analogous reactions to introduce charges.
- Focusing on PHAs with terminal vinyl groups for efficient modification.
- Oxidation of vinyl groups to form carboxylate (anions) and conversion to epoxides followed by amination for amino groups (cations).
Main Results:
- Poly(β-hydroxyalkanoates) with terminal vinyl groups are effective precursors due to high yields and reactive double bonds.
- PHA polyanions are synthesized by oxidizing terminal vinyl groups to carboxylate groups.
- PHA polycations are produced by converting terminal vinyl groups to epoxides and subsequent ring-opening with amines.
Conclusions:
- Charged poly(β-hydroxyalkanoates) can be successfully synthesized using polymer-analogous reactions on functionalized PHA precursors.
- PHAs with terminal vinyl groups offer a versatile platform for generating both PHA polyanions and polycations.
- Further exploration of other functionalized PHAs for similar modifications is warranted.
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