Sequential curing of thiol-acetoacetate-acrylate thermosets by latent Michael addition reactions. (24th March 2017)

• Record Type: Journal Article
• Authors: Konuray, Ali Osman; Liendo, Freddy; Fernández-Francos, Xavier; Serra, Àngels; Sangermano, Marco; Ramis, Xavier
• Is Part Of: Polymer. Volume 113(2017)
• Page Start: 193
• Page End: 199
• Publication Date: 2017-03-24
• Subjects: Michael addition -- Acetoacetate -- Acrylate -- Thermosets -- Photobase; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; 547.7
• DOI: 10.1016/j.polymer.2017.02.072
• Languages: English
• ISSNs: 0032-3861

Abstract

Abstract: Thiol-acetoacetate-acrylate ternary dual-curing thermosets were prepared by a sequential process consisting of thiol-Michael addition to acrylates at room temperature followed by Michael addition of acetoacetates to acrylates at moderately elevated temperature. The curing sequence can be controlled with the help of the different acidities of the protons on thiol and acetoacetate groups, the favorable p Ka of the base used as catalyst and the self-limiting character of Michael additions. The latency of the curing steps can be regulated by selection of the right catalysts, temperature and curing conditions. The properties of the intermediate and final materials can be tuned by changing the structure of the monomers and the contribution of both Michael addition reactions. Graphical abstract: Highlights: A new dual-curing procedure for thiol/acetoacetate/acrylate mixtures is proposed. Acetoacetate-acrylate and thiol-acrylate Michael additions are the curing stages. A photobase generator can be used when high latency is necessary. By changing the contribution of each curing stage, properties can be tuned.