Journal of Dental Research, Vol 69, 844-848, Copyright © 1990 by International & American Associations for Dental Research Online Journals
Cyclopolymerizable monomers for use in dental resin composites
J. W. Stansbury
National Institute of Standards and Technology, Gaithersburg, Maryland 20899.
The simple reaction of conventional monofunctional acrylate monomers with
paraformaldehyde has yielded a new class of difunctional monomers. The
unique proximity of the double bonds within these compounds allows a facile
cyclopolymerization to incorporate a cyclic ether structure into the
polymer backbone. The external position of the acrylate esters means that
these pendant groups can be varied for alteration of the physical
properties of the monomers and the corresponding polymers. A series of the
new monomers has been prepared and polymerized under dilute solution and
bulk conditions to yield non-crosslinked and crosslinked polymers,
respectively. The polymers exhibited high degrees of conversion and
significantly reduced polymerization shrinkage, compared with polymers
obtained from conventional diacrylate or dimethacrylate monomers. These
properties appear to be a direct result of an efficient cyclopolymerization
process. The combination of improved conversion to polymer with less
contraction makes these monomers ideal candidates for use in dental resin
composites. A preliminary evaluation of their potential in this application
has shown that with suitable ester functionality, they can be formulated to
provide composites with excellent mechanical strength properties.
