Journal of Dental Research, Vol 68, 481-483, Copyright © 1989 by International & American Associations for Dental Research Online Journals
Mechanical properties of poly(alkyl alpha-fluoroacrylate)s as denture-base materials
S. Kurata and N. Yamazaki
Department of Chemistry, Kanagawa Dental College, Yokosuka-shi, Japan.
alpha-Fluoro-substituted acryl polymers, poly(methyl alpha-fluoroacrylate)
(PMFA) and poly(2,2,2-trifluoroethyl alpha-fluoroacrylate) (P3FFA) were
investigated for extension to denture-base resins. PMFA, in which fluorine
attaches to the polymer chain, had excellent mechanical properties: For
instance, compressive and bending strength and bending modulus were 50%
higher than those of PMMA. P3FFA, in which fluorines are substituted at the
end of the pendant alkyl ester, showed poor mechanical properties. Contrary
to expectations, the amount of water sorption of PMFA was about twice that
of PMMA, while that of P3FFA was almost zero. Copolymers of MFA and 3FFA
were prepared in an attempt to optimize the mechanical properties and the
water sorption. The copolymer with 40% of 3FFA showed higher compressive,
diametral tensile, and bending strength; in particular, the bending modulus
and water resistance were about 35% and 20% higher, respectively, than
those of PMMA. Improvement of the mechanical properties and increase of the
water sorption of PMFA may be due to intermolecular forces induced by
polarizability of the fluorine and carboxy group along the polymer chain.
Decrease of the water sorption by fluorine substituted on the alkylester
group as in P3FFA may be due to higher hydrophobicity and steric effect of
the fluoroalkyl substitute.
