ApplicationNo. 633145 filed on 11/18/1975
US Classes:558/426, Benzene ring attached indirectly to the cyano group by nonionic bonding (i.e., alicyclic ring between the benzene ring and the cyano group)556/416, Chalcogen bonded directly to plural carbons or double-bonded directly to carbon558/427, Polycyclo ring system having at least three cyclos, at least one of which is a benzene ring558/428, Polycyclo alicyclic ring system containing558/429The ring system contains at least three cyclos
ExaminersPrimary: Brust, Joseph Paul
AbstractDifunctional monomers of the formula, ##STR1## where R is an organic linking group derived from a diol or a dihalide of the formula X--R--X, where X is either chlorine, bromine, iodine, or hydroxy, are prepared by reacting a conjugated diene, exemplified by anthracene, with an ester of 2-cyanoacrylic acid to form the Diels-Alder adduct of the ester. The ester adduct is hydrolyzed to ultimately obtain either the Diels-Adler adduct of either 2-cyanoacrylic acid--alkali metal salt or 2-cyanoacryloyl halide. These latter intermediates are respectively reacted with either the dihalide or the diol to afford the bis-Diels-Alder adduct of the R substituted bis (2-cyanoacrylate) monomer. The protective diene group may then be removed, for example, by reaction with excess maleic anhydride and the resulting difunctional monomer isolated.The difunctional monomers thus prepared can be utilized as crosslinking agents in blends comprising one or more of these difunctional monomers and at least one monofunctional monomer, exemplified by an ester of 2-cyanoacrylic acid. Alternately, one or more difunctional monomers can be homopolymerized or copolymerized to a highly crosslinked polymer. The copolymerized compositions of the monomer blends are particularly useful as adhesives, especially in dental applications for coating or sealing enamel surfaces of teeth to allay decay, or for the bonding of brackets to teeth in orthodontics and bond being substantially more resistant to moisture than where the monofunctional monomer is used alone.