Synthesis of Polyesters Containing Long Aliphatic Methylene Units by ADMET Polymerization and Synthesis of ABA-Triblock Copolymers by One-Pot End Modification and Subsequent Living Ring-Opening Polymerization

Mohamed Mehawed Abdellatif; Kotohiro Nomura

doi:10.1021/acsomega.3c07858

Synthesis of Polyesters Containing Long Aliphatic Methylene Units by ADMET Polymerization and Synthesis of ABA-Triblock Copolymers by One-Pot End Modification and Subsequent Living Ring-Opening Polymerization

ACS Omega. 2024 Feb 15;9(8):9109-9122. doi: 10.1021/acsomega.3c07858. eCollection 2024 Feb 27.

Authors

Mohamed Mehawed Abdellatif^{1

2}, Kotohiro Nomura¹

Affiliations

¹ Department of Chemistry, Graduate School of Science, Tokyo Metropolitan University, 1-1 Minami Osawa, Hachioji, Tokyo 192-0397, Japan.
² Chemistry of Tanning Materials and Leather Technology Department, Chemical Industries Research Institute, National Research Centre, 33 El Buhouth St., Dokki, Giza BP 12622, Egypt.

Abstract

The synthesis of high-molecular-weight (M_n up to 62,000 g/mol) polyesters has been achieved by acyclic diene metathesis (ADMET) polymerization of α,ω-dienes prepared from biobased bis(undec-10-enoate) and diols [ethylene glycol (M1), propylene glycol (M2), 1,9-nonanediol (M3), 1,4-benzenedimethanol (M4), and hydroquinone (M5)] using ruthenium-carbene catalysts. Replacement of the solvent during the ADMET polymerization was effective for obtainment of the high-molecular-weight polymers (expressed as P1-P5). The melting temperatures (T_m) in the resultant polyesters were dependent upon the diol (middle) segment employed, and the polymer prepared from M5 exceeded 100 °C (a T_m value of 122.5 °C). The polymerization of M3 and M4 in the presence of 1,4-cis-diacetoxy-2-butene (DAB, as the chain transfer agent) afforded the telechelic polyesters [P3(OAc)₂ and P4(OAc)₂, respectively] containing acetoxy end groups exclusively. The resultant polymers containing hydroxy group termini [P3(OH)₂ and P4(OH)₂], prepared by the selective deprotection of the acetoxy end groups, were treated with AlEt₃ followed by addition of ε-caprolactone to afford the ABA-type triblock copolymers exclusively, through a living ring-opening polymerization. The depolymerization (hydrolysis) under basic conditions (NaOH aqueous solution) of P3 was explored.