Fast underwater bonding to polycarbonate using photoinitiated cyanoacrylate

Rapid underwater bonding of clear polycarbonate to metal or plastic substrates at temperatures approaching 0 °C was studied. Bonding was achieved within minutes using ethyl 2-cyanoacrylate gel cured using the photoinitiator (dibenzoylferrocene) with a blue-LED light source. The optimum initiator concentration varied from 0.3% to 0.1 wt % for adhesive films 0.5 to 1.2 mm thick, respectively. The polymerisation rate shows a negative temperature dependence making it highly suitable for cold environments. The ultimate shear strength of the bonds was temperature independent and ranged from 1 MPa for metallic to 5 MPa for plastic substrates, respectively.