(a) The average fraction of PNIPAM–water hydrogen bonds as a function of temperature in sodium halide solutions. Different curves represent PNIPAM–water hydrogen bonds in different solutions. (b) The average fraction of water–anion hydrogen bonds as a function of temperature in solutions of sodium halides. Different curves represent different water–anions hydrogen bonds in different solutions. The molecular weight of the polymer chain is M_w = 22500 g·mol⁻¹, and the surface coverage is σ = 0.5 nm⁻².