Short chain alcohols, such as methanol and ethanol, are fairly well miscible in water over full mixing ratios. Moreover, when poly(N-isopropylacrylamide) is added in the same mixtures, the solution phase separates at low alcohol concentrations. From the fundamental understanding of phase separation within the mean-field picture, we can expect interaction parameter χ between water and alcohol to be significantly larger than unity. On the contrary, however, χ remains invariant and close to zero over full mixing ratios of aqueous alcohol mixtures. Here, we show how the preferential binding of poly(N-isopropylacrylamide) with alcohols facilitates local phase separation without altering bulk solution χ.

短链醇（例如甲醇和乙醇）在完全混合比例下可很好地与水混溶。此外，当在相同混合物中加入聚（N-异丙基丙烯酰胺）时，溶液相在低醇浓度下分离。从对中场图像内相分离的基本理解中，我们可以预期水和醇之间的相互作用参数χ明显大于1。相反，在含水醇混合物的全部混合比上，χ保持不变且接近零。在这里，我们显示了聚（N-异丙基丙烯酰胺）与醇的优先结合如何在不改变整体溶液χ的情况下促进局部相分离。