Viscous and Surface Properties of Upper Critical Solution Temperatures of Immiscible Solvents with Biomolecules, Surfactants and Polymer Resin

Abstract

Viscosity and surface tension of upper critical solutions (UCS) of water + phenol with ΔG > 0 are reported. The phenol upper critical solutions within before (B) and after (A) UCS temperatures range are depicted as BUCS and AUCS respectively and were used for study. Viscous flow times (t, sec) and pendant drop numbers (n) were measured together with Survismeter for h/N m s^-2 and g/mN m^-1 respectively. The t and n were repeated for UCS with 0.5 millimol/L proteins (casein, pepsin, EA-Egg, albumin), vitamins [thiamine (B₁), riboflavin (B₂), pyridoxine (B₆)], amino acids (glycine, b-alanine, L-leucine), surfactants dodecyltrimethylammoniumbromide (DTAB), trimethylsulphoxoniumiodide (TMSOI), methyltrioctylammoniumchloride (MTOAC), orcinol and melamineformaldehyde-polyvinylpyrrolidone (MFP). Additives formed UCS at lower temperature with about 60% thermal energy saving. The t and n were used to calculate tn sec^-1 for density calculation with Mansingh equation. The BUCS, UCS and AUCS as pre UCS and post UCS were obtained at 60⁰C, 70⁰C and 61⁰C respectively. The tn with water were obtained for 25 to 70⁰C and plotted with corresponding densities (± 0.05 kg m^-3) for calibration curve used for density calculations. The densities were noted as TMSOI > orcinol > MFP > DTAB > MTOAC, with lower values at 66.5 and higher at 66⁰C.

Keywords

• Biomolecules; polymer resin; hydrophilic; survismeter; hydrophobic interactions