Synthetic routes to degradable copolymers deriving from the biosynthesized polyhydroxyalkanoates: A mini review

Abstract

Abstract.Polyhydroxyalkanoates are a family of natural polyesters being produced as intracellular carbon and energy reserves by a wide variety of microorganisms. They have developed rapidly in both research and development efforts globally in the last 15 years. Till now, over 100 different types of PHAs have been successfully biosynthesized using both genetic engineering and fermentation techniques. Their unique biodegradable, biocompatible and thermoplastic characteristics make PHAs promising candidates for the commodity and biomedical applications. This review focused on the chemical synthesis of the derivatives of the biosynthesized PHAs.

Synthesis and characterization of block poly(ester‐ether‐urethane)s from bacterial poly(3‐hydroxybutyrate) oligomers

“…PEEU properties can be tuned by modifying the chemical nature of the initial compounds and then obtain different types of sequences between two urethane groups. They can be synthesized by either a one or a two‐step process, in solution or in bulk . The advantage of segmented PEEUs over other kinds of materials is that their segments and domain structure can be easily controlled over a considerable range through the selection of materials, their relative proportions and the length of the blocks.…”

Improvement of Mechanical Ductile Properties of Poly(3-hydroxybutyrate) by Using Vegetable Oil Derivatives

“…Thermal degradation of P3HB results in chain scission which leads to a rapid decrease in the molecular weight and this has a negative effect on its overall properties . On the other hand, one important drawback of P3HB is its high stiffness which results in a high fragile polymer due to its high crystallinity . Moreover, P3HB undergoes physical aging due to post‐crystallization processes at room temperature during the storage, which lead to irregular pores formation on the surface .…”

Biotic and Abiotic Synthesis of Renewable Aliphatic Polyesters from Short Building Blocks Obtained from Biotechnology

“…These oligomers can be synthesized by either organometallic- [447] and acid-catalyzed [448] alcoholysis or sodium borohydrate reduction. [430,447,450] Block poly(ester-urethane)s and block poly(ester-ether-urethane)s are obtained with diisocyanates as coupling agentsf or PHA-diols with others blocks, such as oligomers of poly(e-caprolactone), poly(ethylene glycol), poly(butylene adipate),o rP BS. [430,447,450] Block poly(ester-urethane)s and block poly(ester-ether-urethane)s are obtained with diisocyanates as coupling agentsf or PHA-diols with others blocks, such as oligomers of poly(e-caprolactone), poly(ethylene glycol), poly(butylene adipate),o rP BS.…”

“…[449] From these PHA oligomers, different tailored materials can be synthesized,i ncludingb lock poly(ester-urethanes), block poly(ester-ether-urethane)s, and block or randomcopolyesters based on PHA blocks with other blocks. [450] Block, microblock, andr andomc opolyesters are obtained by different processes.B lock copolyesters are synthesized through chemical [382] or enzymatic [354] ROP of lactones/lactides from PHA-diol oligomers, or chain coupling by using an acyl chloride (e.g., terephthaloyl chloride) or 1,3-N,N-dicyclohexylcarbodiimide/4-(dimethylamino)pyridine. [450] Block, microblock, andr andomc opolyesters are obtained by different processes.B lock copolyesters are synthesized through chemical [382] or enzymatic [354] ROP of lactones/lactides from PHA-diol oligomers, or chain coupling by using an acyl chloride (e.g., terephthaloyl chloride) or 1,3-N,N-dicyclohexylcarbodiimide/4-(dimethylamino)pyridine.…”