Rubbery wound closure adhesives. II. initiators for and initiation of 2‐octyl cyanoacrylate polymerization

The polymerization of 2‐octyl cyanoacrylate (OctCA) initiated by five N‐bases [ N , N ‐dimethyl‐ p ‐toluidine (DMT), pyridine (Pyr), triethyl amine (Et 3 N), azobicyclo[2.2.2]octane (ABCO), and diazobicylo[2.2.2]octane (DABCO)] was investigated. Our main objective was to assess the suitability and relative reactivity of these initiators for neat OctCA polymerization as wound closure adhesives. Methodologies were developed to determine stir‐stop and set times of OctCA polymerization and to use these quantities to assess initiation reactivity. According to these studies Et 3 N, ABCO, DABCO, and Pyr are most reactive initiators, while DMT is much less reactive. Polymerizations were much faster in the presence of small amounts of tetrahydrofuran than toluene, indicating solvent polarity effects. Initiator reactivity is discussed in terms of structural parameters. NMR and MALDI‐TOF analyses of low molecular weight P(OctCA) prepared with DMT did not show evidence for the expected aromatic head group proposed by earlier investigators, which suggests complex initiation mechanism. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53 , 1652–1659