Somruethai Channasanon, Wiwaporn Soodsawang, Naruporn Monmaturapoj, and Siriporn Tanodekaew

pp. 429 - 436

Abstract

Poly(alkenoic acid)s based on copolymers of acrylic acid and itaconic acid were synthesized and further modified
with glutamic acid (Glu) and glycidyl methacrylate (GMA). The resultant polymers were characterized by means of proton
nuclear magnetic resonance, gel permeation chromatography, and elemental analysis. Specimens of resin modified glassionomer cement (RMGIC) prepared from the cement-forming reactions between the synthesized polymers and a commercially
reactive glass were fabricated and investigated for flexural strength using three-point bending test. The effects of different
amounts of Glu and GMA on the flexural strength were evaluated. The results showed significantly improved cement strength
due to the incorporation of Glu into the copolymer with an optimal feed of Glu and GMA at 0.1-0.2 and 0.4 per mole of
copolymer, respectively. The addition of 2-hydroxyethyl methacrylate (HEMA) to the RMGIC formulations tremendously
increased the cement strength. In this study, a formulation containing 20%-wt. of HEMA and 45%-wt. of polymer concentration gave the highest flexural strength with 62.7±3.4 MPa.