Home
Resources
Publications
High Glass-Transition Temperature Polymer Networks Harnessing the Dynamic Ring Opening of Pinacol Boronates

High Glass-Transition Temperature Polymer Networks Harnessing the Dynamic Ring Opening of Pinacol Boronates

Juliette Brunet, Franck Collas, Matthieu Humbert, Lionel Perrin, Fabrice Brunel, Emmanuel Lacôte, Damien Montarnal, Jean Raynaud

Angew Chem Int Ed Engl. 2019 Aug 26;58(35):12216-12222.

PMID: 31241821

Abstract:

Differential scanning calorimetry of high molar mass poly(4-vinylphenylboronic acid, pinacol ester)s evidenced unusual reactive events above 120 °C, resulting in a high glass-transition temperature of 220 °C. A reversible ring-opening reactivity of pinacol boronates is proposed, involving a nucleophilic attack on the sp2 boron and subsequent bridging between boron atoms by interconnected pinacol moieties to form a densely crosslinked network with high Tg . FTIR, solid-state NMR investigations, and rheology studies on the polymer as well as double-tagging analyses on molecular model structures and theoretical calculations further support this hypothesis and indicate a ring-opening inducing crosslinking. When diluted in an apolar solvent such as toluene, the polymer network can be resolubilized via ring closing, thus recovering the entropically favored linear chains featuring cyclic boronate esters.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP827614697	1-Propyl-1H-pyrazole-4-boronic acid pinacol ester		827614-69-7	Price
LS793445	4-(3-Ethylureido)-3-methoxyphenylboronic acid, pinacol ester			Price

As a specialist in analytical chemical Products, Alfa Chemistry offers consumers a wealth of raw materials and a full range of technologies and services.

QUICK LINKS

HEADQUARTERS

Tel:

Fax:

Email: