1972

Alpha-cyanoacrylate adhesive compositions each of which comprise a alpha-cyanoacrylic ester and a diacrylic ester compound or dimethacrylic ester compound which is added to the former ester and adhesives prepared from said composiiton having very excellent heat-resisitance.

Fluorinated cyanoacrylates having the formula:

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wherein R is hydrogen, methyl or ethyl, R' is fluorine, -CF3 or -(CF2)nH, and n is an integer from 1 to 3 have been found to be useful adhesives which when applied as monomers to adherends rapidly polymerize in the presence of even small amounts of e.g. moisture to form strong bonds. The monomers also polymerize to films and can be used biologically as hemostatics and tissue adhesives.

A new step in the condensation of formaldehyde and esters of 2-cyanoacetic acid to produce 2-cyanoacrylate esters which consists essentially of catalyzing the reaction by means of a mixture of an acid and the salt of a primary or secondary amine with the same stronger acid. To be effective, the catalytic mixture should have a pH value of 5 or less when exact amounts of its components are dissolved in 25 ml. of water. If the catalytic mixture is to include an acid which is not readily soluble in water (e.g. organic acids), then the pH is measured in 25 ml.