Presently described are curable compositions comprising a mixture of at least one (e.g. free-radically) polymerizable ionic liquid and at least one other ethylenically unsaturated monomer, oligomer, or polymer. The polymerizable ionic liquid is characterized as having an air to nitrogen curing exotherm ratio of at least 0.70. Also described are articles and methods of making articles from such curable compositions. A monofunctional polymerizable ionic liquid is also described comprising a non-polymerizable substituted imidazolium cationic group and a polymerizable sulfonate anion.