Role of hydrogen bonding in solubility of poly(N-isopropylacrylamide) brushes in sodium halide solutions

Zhao Xin-Jun^{1, 2, †,}, Gao Zhi-Fu³

(a) Local fraction of PNIPAM–water hydrogen bonds as a function of distance from the substrate surface in pure water. (b) The average fraction of PNIPAM–water hydrogen bonds as a function of temperature in pure water. The molecular weight of the polymer chain is M_w = 22500 g·mol⁻¹, and the surface coverage is σ = 0.5 nm⁻².