Issue 23, 2019

Understanding the ring-opening polymerisation of dioxolanones

Abstract

Sustainable monomers built from ring-closed α-hydroxyacids to form 1,3-dioxolane-4-ones (DOX) are both easily prepared and functional group tolerant. Subsequent ring-opening polymerisation (ROP) of DOX furnishes a broad scope of functional poly(α-hydroxy acid)s (PAHAs). Elusive polymers like isotactic poly(mandelic acid) are accessible and we now report that the formaldehyde eliminated during the polymerisation can induce a competing side reaction. In this contribution, we propose a new mechanism of ring-opening for these monomers, involving competitive elimination and a subsequent Tishchenko reaction facilitated by formaldehyde. Both catalyst design and polymerisation methodology can be modified to reduce the impact of the Tishchenko reaction, with sterically-unencumbered and electronically-neutral salen aluminium catalysts exhibiting the best performance in the ROP of 5-phenyl-1,3-dioxolane-4-one (PhDOX), providing the best balance of reactivity and selectivity. Importantly, crystalline poly(mandelic acid) was obtained using a dynamic vacuum ROP either neat or in diphenyl ether, where volatilisation of the formaldehyde allows for production of polymers with thermal properties competitive with commercial polystyrene.

Graphical abstract: Understanding the ring-opening polymerisation of dioxolanones

Supplementary files

Article information

Article type
Paper
Submitted
29 নভে. 2018
Accepted
25 জানু. 2019
First published
28 জানু. 2019

Polym. Chem., 2019,10, 3048-3054

Understanding the ring-opening polymerisation of dioxolanones

Y. Xu, M. R. Perry, S. A. Cairns and M. P. Shaver, Polym. Chem., 2019, 10, 3048 DOI: 10.1039/C8PY01695J

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements