Fig. 3: Change in hydrogen bonding during stretching.
From: Delayed crystallization response-inspired waterborne polyurethane with high performance
a FT-IR spectra showing the C = O and b −NH− stretching bands at different stretch ratios (λ). c, d 2DCOS synchronous and asynchronous spectra calculated for the 1800−1600 cm-1 band of HPWPUE. e, f 2DCOS synchronous and asynchronous spectra calculated for the 3600−3150 cm-1 band of HPWPUE. Red and blue areas indicate positive and negative values, respectively, and signal intensity increases with color intensity. g Schematic diagram illustrating the changes in hydrogen bonding and binding energy, as inferred from the 2D correlation spectra during stretching.
