Paper Number
PO8 

Session
Poster Session

Title
Effect of additives on the microstructure and flow behavior of concentrated surfactant solutions

Presentation Date and Time
October 12, 2022 (Wednesday) 6:30

Track / Room
Poster Session / Riverwalk A

Authors (Click on name to view author profile)

  1. Kelkar, Parth U. (Purdue University, School of Materials Engineering)
  2. Nance, Bradley (Purdue University, School of Materials Engineering)
  3. Kaboolian, Matthew (Purdue University, School of Materials Engineering)
  4. Eisenman, Katherine G. (Carnegie Mellon University, Department of Materials Science and Engineering)
  5. Corder, Ria D. (Purdue University, School of Materials Engineering)
    Corder, Ria D. (Purdue University, School of Mechanical Engineering)
  6. Lindberg, Seth (The Procter & Gamble Co)
  7. Stenger, Patrick (The Procter & Gamble Co.)
  8. Erk, Kendra A. (Purdue University, School of Materials Engineering)

Author and Affiliation Lines (in printed abstract book)
Parth U. Kelkar1, Bradley Nance2, Matthew Kaboolian3, Katherine G. Eisenman4, Ria D. Corder1,5, Seth Lindberg6, Patrick Stenger6 and Kendra A. Erk1
1School of Materials Engineering, Purdue University, West Lafayette, IN 47907; 2School of Materials Engineering, Purdue University, West Lafayette, IN 47906; 3School of Materials Engineering, Purdue University, West Lafayette, IN 47906; 4Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213; 5School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907; 6The Procter & Gamble Co, West Chester, OH 45069

Speaker / Presenter 
Kelkar, Parth U.

Keywords
rheometry techniques; surfactants

Text of Abstract
Globally, industries are striving to create products and processing pipelines with lower environmental footprints using more concentrated feedstocks. However, many conventional production methods cannot effectively process concentrated materials without altering their microstructure and/or sustaining higher costs. This poster will describe ongoing research activities to determine how the structure and properties of surfactant bilayers within concentrated lamellar solutions affect their flow and processability. Three industrially relevant additives – monovalent salt (NaCl), propylene glycol and a fatty alcohol blend were separately added in varying concentrations (0.25-10 wt.%) to a lamellar-structured 70 wt.% sodium lauryl ether sulfate (SLES) solution. Rheological behavior was investigated using shear rotational and oscillatory experiments. Confocal microscopy and small-angle X-ray scattering measurements were also employed to quantify microstructural differences with variation in additive concentration and shear history. Oscillatory temperature ramps and calorimetry experiments were conducted to evaluate flow behavior across processing and end-use relevant temperatures. Going further, the effect of additives on the development of microscopic flow instabilities will be determined using ultrasound-based rheo-flow velocimetry. Preliminary results show that salt and propylene glycol behave respectively as a desiccant and plasticizer, affecting both the rheology and microstructure of the SLES solutions. Outcomes from rheometry, microscopy, calorimetry, and scattering experiments shed light on key processing-relevant parameters, including critical shear rates and transition temperatures.