Using spinning drop tensiometry to determine the square gradient parameter for dodecyl acrylate/poly (dodecyl acrylate) for use in the tipmps flight investigation

Two techniques were used to estimate the square gradient parameter for a dodecyl acrylate, poly (dodecyl acrylate) system. Using spinning drop tensiometry an effective interfacial tension (EIT) of 0.08 +/- 0.01 mN/m was measured at 27 +/- 1 °C. The corresponding transition zone width was determined to be 0.10 mm, yielding a square gradient parameter of 5-8 × 10-9 N. A numerical approach using various thermodynamic theories coupled with concepts from light scattering yielded a molecular weight dependent square gradient parameter. The resulting values were shown to fall within the range of 10-11-10-9 N for MW\u27s of 104-106. © 2003 by John A. Pojman. Published by the American Institute of Aeronautics and Astronautics, Inc., with permission