Ethylene–vinyl alcohol copolymers
(EVOHs) are important
materials available in a variety of compositions and valued in countless
applications. In spite of their great adaptability offered by the
adjustment of their ethylene content, the chemical modification of
EVOHs is often considered to tune their properties and functionalities
in order to meet the stringent requirements of today’s applications.
While post-polymerization modification of the pendant hydroxyl groups
of EVOHs is the prevailing functionalizing strategy, this multistep
approach consumes part of the alcohols of EVOHs and remains limited
in terms of functions. This work reports a straightforward platform
for the synthesis of functional EVOHs, in particular, amino derivatives,
involving a CO2-derived oxazolidinone-containing methylene
heterocycle, namely, 4,4-dimethyl-5-methyleneoxazolidin-2-one (DMOx).
The ethylene/DMOx and ethylene/vinyl acetate/DMOx copolymerizations
were implemented by conventional and reversible deactivation radical
copolymerization. The resulting oxazolidinone-containing ethylene-based
copolymers were then converted into novel vicinal amino alcohol-functional
EVOHs via hydrolysis of esters and oxazolidinones. A selective post-modification
method of these 1,2-amino alcohol-functional EVOHs into their oxazolidine
counterparts is also reported. Finally, the peculiar thermal and solution
properties, including pH-responsiveness, of these novel vicinal amino
alcohol- and oxazolidine-functional EVOHs as well as oxazolidinone
EVAs are discussed.