Novel rubbery wound closures containing various proportions and molecular weights of polyisobutylene (PIB) and poly(2-octyl cyanoacrylate) [P(OctCA)] for potential clinical use were designed, synthesized, characterized, and tested. Homo-networks were prepared by crosslinking 3-arm star-shaped PIBs fitted with terminal cyanoacrylate groups, [Ø(PIB-CA) 3 ], and co-networks by copolymerizing Ø(PIB-CA) 3 with OctCA using N-dimethyl-p-toluidine (DMT). Neat Ø(PIB-CA) 3 , and Ø(PIB-CA) 3 /OctCA blends, upon contact with initiator, polymerize within seconds to optically transparent strong rubbery co-networks, Ø(PIB-CA) 3 -co-P(OctCA). Homo-and co-network formation was demonstrated by sol/gel studies, and structures and properties were characterized by a battery of techniques. The T g of P(OctCA) is 58 o C by DSC, and 75 o C by DMTA. Co-networks comprising 25% Ø(PIB-CA) 3 (M n = 2400 g/mol) and 75% P(OctCA) are stronger and more extensible than skin. Short and long term creep studies show co-networks exhibit high dimensional stability and <6 % creep strain at high loading. Co-networks upon contact with DMT polymerize within seconds and produce transparent rubbery coatings on porcine skin. When deposited on porcine skin co-networks yield hermetically-adhering clear rubbery coatings. Strips of porcine skin coated with co-networks could be stretched and twisted without compromising membrane integrity. The co-network is non-toxic to L-929 mouse fibroblasts.

The polymerization of 2‐octyl cyanoacrylate (OctCA) initiated by five N‐bases [N,N‐dimethyl‐p‐toluidine (DMT), pyridine (Pyr), triethyl amine (Et3N), 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 Et3N, 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