Vinyl epoxide accelerators for the photoinitiated cationic polymerization of oxetane monomers. (1st May 2015)

• Record Type: Journal Article
• Authors: Crivello, James V.
• Is Part Of: Polymer. Volume 64(2015)
• Page Start: 227
• Page End: 233
• Publication Date: 2015-05-01
• Subjects: Cationic polymerization -- Photopolymerization -- Oxetanes; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; 547.7
• DOI: 10.1016/j.polymer.2015.01.019
• Languages: English
• ISSNs: 0032-3861

Abstract

Abstract: Epoxides bearing vinyl groups bonded to one of the carbon atoms of the three-membered ring, exhibit the ability to dramatically increase the rate of the photoinitiated cationic polymerization of 3-mono- and 3, 3-disubstuted oxetanes by eliminating or sharply reducing the length of the induction periods. This effect, termed by us as "kick-starting", results from the ability of the aforementioned epoxides to undergo ring-opening on protonation to yield resonance stabilized allylic carbocations. Several examples are given of "kick-starting" epoxides together with their use in the photopolymerization of various oxetane monomers. Graphical abstract: Highlights: Vinyl substituted epoxides markedly accelerate the photoinitiated cationic ring-opening polymerization of oxetane monomers. Acceleration effects are observed upon the addition of small (3–5 wt%) of the epoxide to the oxetane monomer. The apparent acceleration results from elimination of the induction period. Experimental evidence indicates that the acceleration effect derives from a change in the mechanism of initiation. "Kick-started" oxetanes are compatible with high speed UV-curable coatings, printing inks and pressure sensitive adhesives.