IADR Abstract Archives
Effect of Initiator Systems on Kinetic of Polymerization of Experimental Resins
Objectives: Objectives: The aim of the present study was to evaluate the influence of different initiator system on kinetic of polymerization and rate of curing of experimental resins.
Methods: Methods: Experimental light-activated resin composites (45 vol% inorganic filled in 50/50mass% bis-GMA/TEGDMA) were formulated. Eight different groups were established according to the type and concentration of initiator system (camphorquinone (CQ) 0.5mol% or 1mol%; CQ 0.5 or 1mol% + diphenyliodonium hexafluorophosphate (DPI) 0.5mol%; phenylbis phosphine oxide (BAPO) 0.5 or 1mol% and monoacylphosphine oxide (MAPO) 0.5 or 1mol%). Polymerization kinetics was monitored on an attenuated total reflectance (ATR) accessory attachment of an (FTIR) spectrometer (Nicolet iS50, Thermo Fisher, Madison, USA).
Results: Results: The resins containing only CQ presented lower degree of conversion as well as reduced rate of polymerization compared to the other groups. The addition of DPI resulted in increased degree of conversion and rate of polymerization to the resins containing CQ, promoting the higher rate of curing compared to the other initiator systems. Resins containing BAPO presented the higher degree of conversion.
Conclusions: Conclusions: It could be concluded that the addition of DPI can increase the reactivity of resins containing CQ, promoting higher curing speeds than the type I initiators tested. Despite the intermediary results on rate of polymerization, BAPO can promote higher degree of conversion on the experimental resins evaluated.
Methods: Methods: Experimental light-activated resin composites (45 vol% inorganic filled in 50/50mass% bis-GMA/TEGDMA) were formulated. Eight different groups were established according to the type and concentration of initiator system (camphorquinone (CQ) 0.5mol% or 1mol%; CQ 0.5 or 1mol% + diphenyliodonium hexafluorophosphate (DPI) 0.5mol%; phenylbis phosphine oxide (BAPO) 0.5 or 1mol% and monoacylphosphine oxide (MAPO) 0.5 or 1mol%). Polymerization kinetics was monitored on an attenuated total reflectance (ATR) accessory attachment of an (FTIR) spectrometer (Nicolet iS50, Thermo Fisher, Madison, USA).
Results: Results: The resins containing only CQ presented lower degree of conversion as well as reduced rate of polymerization compared to the other groups. The addition of DPI resulted in increased degree of conversion and rate of polymerization to the resins containing CQ, promoting the higher rate of curing compared to the other initiator systems. Resins containing BAPO presented the higher degree of conversion.
Conclusions: Conclusions: It could be concluded that the addition of DPI can increase the reactivity of resins containing CQ, promoting higher curing speeds than the type I initiators tested. Despite the intermediary results on rate of polymerization, BAPO can promote higher degree of conversion on the experimental resins evaluated.