Adhesion of Synthetic Organic Polymer on Soft Tissue. II. The Preparation and Some Properties of a Fast-Setting Polyurethane Adhesive

Abstract

A method has been developed to provide a moderate amount of tetrafluoro-1,3-phenylene diisocyanate in good yield. The incorporation of this extremely reactive diisocyanate in a polyurethane prepolymer has practically attained the limit of reducing the setting time of this type of adhesive for bonding living biological tissues. The adhesion of prepolymer preparations evaluated in vivo had indicated that the concentration of tolylene diisocyanate required for good bonding is 50% less than in a previous preparation. The pot-life of the prepolymer adhesive varies with the amount of the fluorinated diisocyanate and pyridine. The stability can be extended to at least 1 year by dilution with anhydrous methylene chloride. Adequate elimination of the diluent after the adhesive has been applied on tissue can be facilitated by aerosol propellants. However, the extension of pot-life in aerosol dispensers has not been determined. The prepolymer adhesive prepared by mixing sterilized components has effected similar bonding on tissue as an unsterilized sample. Preliminary acute toxicity studies indicate that this polyurethane material is also well tolerated, but the barrier present in wounds bonded by the adhesive has caused delay in the normal healing process. Therefore, for further evaluation in vivo, this prepolymer adhesive should be used as a sealant or coating.