Effect on adhesion of new polymerization initiator systems comprising 5‐monosubstituted barbituric acids,aromatic sulfinate amides,and tert‐butyl peroxymaleic acid in dental adhesive resin

To develop a multipurpose dental adhesive resin, the effects of polymerization initiator systems comprising 5‐monosubstituted barbituric acid (5‐MSBA), aromatic sulfinate amide (ASA), and tert‐butyl peroxymaleic acid (t‐BPMA) with 4‐acryloxyethyltrimellitic acid (4‐AET) or its anhydride (4‐AETA) on adhesion and curing time were investigated. Tensile bond strength values of a Ni Cr alloy are affected by the inclusion of t‐BPMA, and the optimum concentration of t‐BPMA in a 5‐MSBA–ASA–t‐BPMA‐type initiator system was found to be 0.5–2.0 wt %, and it was noteworthy that the correlation between the tensile bond strength and curing time on the t‐BPMA‐concentration showed a highly negative correlation of a benzenesulfinate morphoride (BSMo) series adhesive: r = −0.957, and a p‐toluenesulfinate morphoride (p‐TSMo) series adhesive: r = −0.949. The combination of 1‐cyclohexyl‐5‐ethylbarbiturioc acid (CEBA) with ASA provides a high level of tensile bond strength to the Ni Cr alloy, and the optimum concentration of CEBA in a CEBA–ASA–t‐BPMA‐type initiator and the bond strength values were found to be 0.75 wt % CEBA: 52.3 MPa (with BSMo), and 1.0 wt % CEBA: 50.9 MPa (with p‐TSMo), respectively. It was suggested that 5‐MSBA, ASA, and t‐BPMA and their combinations provided the environment where 4‐AETA exhibited good bonding performance with increasing wettability to metal without interference of a charge‐transfer complex derived from a polymerization initiator system such as benzoyl peroxide (BPO)–amine. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1655–1668, 1999