Figure 5.

(a) GPC spectra for the product of prepolymer synthesis with an H₁₂MDI:DMPA molecular ratio of 2:1 (H₁₂MDI_DMPA) (red line), pure H₁₂MDI (blue dashed line), and pure DMPA (green dashed line). The origin of peaks is labeled by blue rectangles and green ovals, representing H₁₂MDI and DMPA, respectively. “n” describes the composition of the H₁₂MDI-DMPA fragments, which comprise n DMPA and (n + 1) H₁₂MDI. (b) FTIR spectra of a dried H₁₂MDI_DMPA film. The inset shows the region of C=O bond stretching (∼1700 cm^–1) and N–H bond bending (∼1630 cm^–1) of urethane. (c) SAXS profile of 1.5 wt % aqueous solution of H₁₂MDI_DMPA (red) compared to a representative PUD sample, 1 wt % aqueous dispersion of HB70_SS2000, (blue).