COPOLYMERIZATION AND ACTIVATION OF PEROXIDE DECOMPOSITION WITH ACRYLIC DERIVATIVES OF TERTIARY AROMATIC-AMINES

The reactivity parameters of the copolymerization of N,N-bis(2-methacr yloyloxyethyl)-p-toluidine (BMAT) (M1) with methyl methacrylate (MMA) (M2) in 1,4-dioxane, i.e. r1 = 1.07 +/- 0.20, and r2 = 0.11 +/- 0.19, and with bisphenol-A bis(2-hydroxypropyl methacrylate) (Bis-GMA) (M2) in benzene, i.e. r1 = 0.58 +/- 0.04, and r2 = 0.03 +/- 0.03, were dete rmined at 60-degrees-C at low concentration and low conversion (approx imately 5%) of the monomers. Strongly delayed gelation occurred during the copolymerization of BMAT and MMA at monomer conversions of 20-30% , relatively independently of the composition of the monomer mixture. The efficiency of BMAT and N-acryloyl-N'-phenylpiperazine as activator s in the redox initiated copolymerization of Bis-GMA in dental composi tes at ambient temperatures was found to be comparatively low. In the case where BMAT was used in equimolar proportions to benzoyl peroxide the former component was not detectable in the extract of the cured co mposite.