Figure 6.

Effect of the calcium concentration on the physical properties of LMP films. The LMP films were cured to a 15.7 ± 6.6% (w/w) water content; mean values of a minimum of 10 films are shown. (A) Burst strength of the films, reflecting the fracture resistance to a uniaxial load applied at a velocity of 0.5 mm/s (see Figure 3), decreased with an increasing calcium concentration (R² = 0.938). (B) The spring constant, measured as the film displacement and applied force in the 3-point bend test, increased with an increasing calcium concentration (R² = 0.9813). (C) Similarly, the stiffness, measured as the resistance to both the fracture probe and the 3-point bend test (see Figure 2 and Figure 4), increased with an increasing calcium concentration (R² = 0.9427). (D) The bend threshold, measured as the probe distance at the yield point in a modified 3-point bend test, decreased with an increasing calcium concentration (R² = 09229). Error bars = 1 SD.