05/25/2021
By Sokny Long

The Francis College of Engineering, Department of Plastics Engineering, invites you to attend a Master’s thesis defense by Hadyn Beirne on “Effects of Processing on Thermally Conductive Thermoplastic Elastomer Tubing.”

MSE Candidate Name: Hadyn Beirne
Defense Date: Friday, June 4, 2021
Time: 11 a.m. to noon EST
Location: This will be a virtual defense via Zoom. Those interested in attending should contact Hadyn_Beirne@student.uml.edu and committee advisor, Stephen_Johnston@uml.edu, at least 24 hours prior to the defense to request access to the meeting.

Committee Chair (Advisor): Stephen Johnston, Associate Professor, Plastics Engineering, University of Massachusetts Lowell

Committee Members:

  • Margaret Sobkowicz-Kline, Associate Professor, Plastics Engineering, University of Massachusetts Lowell
  • Hunter Mack, Associate Professor, Mechanical Engineering, University of Massachusetts Lowell
  • Hongwei Sun, Professor, Mechanical Engineering, Northeastern University

Brief Abstract:

This research focuses on how processing effects the mechanical performance of thermally conductive tubing in the US Army’s Microclimate Cooling System (MCS). The PVC originally used in the MCS was identified as a limiting factor in the thermal conductivity heat transfer of the system. Modern Dispersions Inc. supplied the project with two different thermally conductive, thermoplastic elastomeric tubing materials to suit the task (TCC’s).

The thermally conductive compounds were master batch materials and as such needed to be compounded with another material to tailor their mechanical properties; for the task, elastomeric Dow Engage 8003 was selected. A let down study was created in which multiple loading levels were created and tested to find the optimal TCC loading level that reaches a balance in the trade-off of mechanical performance and thermal performance. Once a proper level was determined, the optimally loaded tubing went through a processing DOE to identify the conditions that could maximize the desired mechanical properties of the tube. The DOE studied how draw down ratio, cooling rate, and shear history effected kink, tensile, and burst performance.

Upon analysis of the results, the thermally conductive compounds were found to both slightly underperform Tygon mechanically and outperform it in thermal conductivity. Overall, it was found that draw down ratio and shear history had little effect on mechanical performance, but cooling rate showed a strong effect that differed depending on the TCC used.

All interested students and faculty members are invited to attend the online defense via remote access.