Rubbery wound closure adhesives. I. design, synthesis, characterization, and testing of polyisobutylene-based cyanoacrylate homo- and co-networks

Abstract

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.

Polycyanoacrylates

“…New rubbery wound closure adhesives based on 2-octylcyanoacrylate and polyisobutylene functional cyanoacrylates have recently been investigated for their improved flexibility (127) and control of set time (128). For internal surgical procedures, lower toxicity and faster degrading adhesives are of future interest.…”

Cationic half‐sandwich scandium complex for the synthesis of polyisobutylene with high molecular weight under mild conditions

“…Polyisobutylene and isobutylene–isoprene copolymer (IB‐IP copolymer) attracted a lot of attention in scientific research and industrial application in recent decades, because of their excellent thermal and oxidative stability, chemical resistance, biocompatibility, high hysteresis, and low permeability to gases . To obtain polyisobutylene with high molecular weight ( M n ), the cationic polymerization process of polyisobutylene‐based elastomers is always subjected to energy and environmental issues, such as the use of low temperature (–100 °C) and noxious chlorinated solvents, so the relatively high temperature procedures as well as environmental friendly systems are pursued and have been proposed elsewhere as a desirable option of great scientific interests …”

High‐molecular‐weight polyisobutylenes (PIBs) and PIB networks from liquid PIBs by thiol‐ene clicking

“…Extracted samples were removed from the solvent, vacuum dried for 24 h at 30 °C and weighed. Weight percent sol fraction (extractable) was obtained by where m dry and m ex are sample weights before and after extraction, respectively …”