Comparison of the visco-elastic behavior of a pre-impregnated reinforced glass fiber composite with resin-based composite.

OBJECTIVES: The visco-elastic behavior of a pre-impregnated reinforced glass fiber composite (everStick) was compared with a resin-based particulate composite (Filtek P60) by using dynamic mechanical analysis (DMA) to determine their storage modulus (E') and damping ratio (tandelta).
METHODS: These materials were subjected to three-point bend tests using a PerkinElmer DMA7. In temperature mode, the temperature was increased from 26 to 140 degrees C at 1 Hz. In frequency mode, the range was 1-10 Hz at a constant temperature of 37 degrees C.
RESULTS: In both temperature and frequency modes, E' for everStick was significantly higher and tandelta was significantly lower than those for Filtek P60, indicating that the stiffness of the pre-impregnated glass fiber composite was higher and its damping property was lower than those for resin-based particulate composite. SIGNIFICANCE: The glass fiber restorative composite appears to absorb less energy in repeated stress and is less likely to retain external energy as residual stress.