Binding of Short Alkyl Chain Surfactants to the (Ethylene oxide)13−(Propylene oxide)30−(Ethylene oxide)13 and (Ethylene oxide)75−(Propylene oxide)30−(Ethylene oxide)75 Copolymers Studied by Microcalorimetry

摘要: The enthalpy of transfer (ΔHt) neutral copolymers, at a fixed and low concentration ca. 10-3 mol kg-1, from water to the aqueous surfactant solutions as function (fSmS) was determined 25 °C. surfactants studied are sodium octanoate, decanoate, N-octylpyridinium chloride (OPC), N,N-dimethyloctylamine-N-oxide (ODAO). copolymers (ethylene oxide)13−(propylene oxide)30−(ethylene oxide)13 (L64) oxide)75−(propylene oxide)75 (F68). two show different hydrophilic−hydrophobic ratios, larger being for F68. As general feature, shape ΔHt vs fSmS curve depends on nature whereas magnitude essentially both copolymer. A quantitative analysis experimental data systems investigated done. L64 F68 in ODAO behave like classical hydrophobic nonionic additives. OPC does not exhibit s...