title: Determination of neutralization capacity and stability of a basic methacrylate monomer using NMR.
abstract: The durability of dental resin depends on the stability of the polymer. The neutralizing capacity of a basic methacrylate monomer and its chemical stability were measured using nuclear magnetic resonance (NMR) spectroscopy. Lactic acid solution was titrated with 2-(dimethylamino)ethylmethacrylate (DMAEMA) or 2-hydroxyethylmethacrylate (HEMA) and its chemical shifts monitored. Addition of DMAEMA alters the chemical shift proportionally to pH neutralization, whereas HEMA has no impact. Chemical shifts were used to quantify both the change in pH and monomer stability. The results demonstrate that neutralization by basic monomer can be achieved and that this can be measured using an NMR assay.
authors.affiliation: Bioengineering Research Center, University of Kansas, Lawrence, KS, USA.
authors.forename: Jonggu
authors.initials: J
authors.lastname: Park
authors.forename: Qiang
authors.initials: Q
authors.lastname: Ye
authors.forename: Paulette
authors.initials: P
authors.lastname: Spencer
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Laurence