Thermomechanical Analysis of Phase Transitions in a Binary Mixture of Ethylene Glycol and Water

Open Access
Author:
Puthenpurayil, Joseph Kurian
Area of Honors:
Chemistry
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Bratoljub Milosavljevic, Thesis Supervisor
  • Pshemak Maslak, Honors Advisor
  • Mark Maroncelli, Faculty Reader
Keywords:
  • Ethylene Glycol
  • Viscosity
  • Thermomechanical Analysis
  • TMA
  • Water
  • Glass Transition
  • Phase Diagram
Abstract:
Thermomechanical analysis (TMA) technique was used to study rheological properties in order to better understand the low temperature, solid-liquid phase transition in the phase diagram of the ethylene glycol (EG) and water binary mixture system (EG-water) at mixture compositions of 20, 40, 60, 65, 70, 75, 80, 85, and 88.7 weight percent EG-water. This phase transition was explored using three repeated trials at each composition with the expansion probe and a 10°C/min ramp. The temperature points at which the viscosity becomes infinitely high do not correspond with the solidus found in most recently published literature. In the composition range from 60 to 88.7% wt. EG-water, the experimentally determined solid-liquid transition falls around 50°C below the literature solidus, and follows a similar trend to another proposed diagram’s glass phase transition at about 30°C above. The sample was also seen to be amorphous under X-ray studies at -150°C by Dr. Milosavljevic.