Figure 3. Results from the 2x4 design with 2 levels of chitosan lactate and 4 levels of powder:liquid ratio. In (A), a brittle-to-ductile transition occurred at 15% chitosan lactate, and the strain-at-peak-load was increased over 70 times. In (B), at each powder:liquid ratio, the strengths with 15% chitosan lactate were always higher than those without chitosan lactate (p < 0.05).