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

Abstract

Telechelic hydroxylated poly(3‐hydroxybutyrate) (PHB‐diol) oligomers have been successfully synthesized in 90–95% yield from high molar mass PHB by tin‐catalyzed alcoholysis with different diols (mainly 1,4‐butanediol) in diglyme. The PHB‐diol oligomers structure was studied by nuclear magnetic resonance, Fourier transformed infrared spectroscopy MALDI‐ToF MS, and size exclusion chromatography, whereas their crystalline structures, thermal properties and thermal stability were analyzed by wide angle X‐ray scattering, DSC, and thermogravimetric analyses. The kinetic of the alcoholysis was studied and the influence of (i) the catalyst amount, (ii) the diol amount, (iii) the reaction temperature, and (iv) the diol chain length on the molar mass was discussed. The influence of the PHB‐diol molar mass on the thermal stability, the thermal properties and optical properties was investigated. Then, tin‐catalyzed poly(ester‐ether‐urethane)s (PEEU) of Mn = 15,000–20,000 g/mol were synthesized in 1,2‐dichloroethane from PHB‐diol oligomers (Pester) with modified 4,4'‐MDI and different polyether‐diols (Pether) (PEG‐2000, PEG‐4000, and PPG‐PEG‐PPG). The influence of the PHB‐diol chain length, the Pether/Pester ratio, the polyether segment nature and the PEG chain length on the thermal properties and crystalline structures of PEEUs was particularly discussed. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1949–1961

Functionalization of poly(3‐hydroxybutyrate) with different thiol compounds inhibits MDM2–p53 interactions in MCF7 cells

“…Various methods have been discovered that enhance the properties of PHB polymer materials. The blending of biodegradable PHB with other polymers, such as poly(ε‐caprolactone) (PCL), poly(butylene glycol adipate), poly(ethylene glycol), and block poly(ester–ether–urethane)s, allows one to overcome the difficulties connected with the use of bacterial PHB as a thermoplastic material. These polymer blends possess much better physical properties, including lower melting points and higher extensibility compared to neat PHB.…”

“…Another method used to enhance the properties of PHB is the chemical modification of end functional groups of PHB. The hydroxyl functionalization of PHB (PHB–diol) is obtained by transesterification reactions of PHB with 1,4‐butanediol with p ‐toluene sulfonic acid as a catalyst . PHB–diol can be acylated with α‐bromoisobutyryl bromide to produce a highly reactive macroinitiator from both end sides; this can allow further modifications, such as copolymerization .…”

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.…”

“…To obtaint hese structures, controlled PHA oligomers must be obtained by PHA molar mass reduction with functionalization to obtain telechelic hydroxy-terminated PHAs (PHA-diol). These oligomers can be synthesized by either organometallic- [447] and acid-catalyzed [448] alcoholysis or sodium borohydrate reduction. [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.…”

“…[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. [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. [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.…”