03/11/2025
By Kwok Fan Chow

The Kennedy College of Science, Department of Chemistry, invites you to attend a Ph.D. Research Proposal defense by Tianhao Ming entitled “Self-plasticizing PVC Coatings Reinforced with Surface Functionalized Silk for Applications under Extremely Low-temperature Conditions.”

Degree: Doctoral
Location: Olney Hall, Room 520
Date: Friday, March 21, 2025
Time: Noon

Committee Chair:
Professor Yuyu Sun, Department of Chemistry, University of Massachusetts Lowell

Committee Members:
Professor James Reuther, Department of Chemistry, University of Massachusetts Lowell
Professor James Whitten, Department of Chemistry, University of Massachusetts Lowell
Walter X. Zukas, Ph.D., Combat Capabilities Development Command (CCDC) Soldier Center, US Army Devcom Soldier Center

Abstract:
Polymeric surface coatings are widely used for protecting various materials, including metals, plastics, and concrete, from corrosion, weathering, and mechanical damage. Among them, Polyvinyl chloride (PVC) coatings are particularly favored due to their excellent chemical resistance, durability, and versatility, making them attractive candidates in construction, automotive, marine, electrical, gloves, boots, and shelters where long-term protection of materials is crucial. However, PVC coating cannot be readily used at extremely low temperatures, such as the Arctic environment, where the temperature can be as low as -54℃. This is because PVC's glass transition temperature (Tg) is at 80℃-85℃. The polymer becomes very brittle in the Arctic environment and loses protective functions. To improve low-temperature performance, the industry usually physically mixes plasticizers with PVC to soften the material. However, this strategy has two significant drawbacks: (1) the plasticizers will migrate with time, which will lead to the deterioration of the properties and cause health problems for the users; and (2) with PVC Tg decreases, the plasticizer content needs to increase significantly, which will cause low mechanical properties of the coatings.
In this study, to develop a PVC protective coating that can be used in extremely low-temperature environments without the problems of conventional plasticization, we propose to covalently bond plasticizers onto the PVC polymer backbones to produce “self-plasticizing” low Tg PVC (SP-PVC) and prevent migration. We also propose using silk to reinforce the SP-PVC and maintain mechanical properties.

All interested students and faculty members are invited to attend.