The Department of Chemical Engineering welcomes you to hear Professor Boxin Zhao and his former students, PhD graduates Fut (Kuo) Yang and Aleksander Cholewinski, discuss their innovation: a hybrid material composed of a polymer impregnated with a supercooled salt solution, termed sal-gel, that assumes two distinct but stable solid states under the same range of temperatures and pressure.
All graduate ChE students will receive an Outlook calendar event with webinar access details.
Everyone is welcome. If you are not a graduate ChE student, contact the Manager of Graduate Studies for the access information you need to join the webinar.
Abstract
Innovation in functional materials is integral to the advances of chemical engineering, which excels in transforming raw chemical ingredients into valuable products and devices to benefit human well-being and society.
In this seminar, Zhao, Yang and Cholewinski will report on and discuss the development of a new type of stiffness-changing material. Stiffness-changing materials can be strong, yet adaptable, finding uses across multiple applications; however, to maintain a second solid state they require a constant stimulus or set of environmental conditions.
Their innovation is a hybrid material composed of a polymer impregnated with a supercooled salt solution, termed sal-gel, that assumes two distinct but stable solid states under the same range of temperatures and pressure. Upon transient stimulation of nucleation, the material switches from a clear and soft solid to a white and hard state, which can be 104 times stiffer than the original (15 kPa vs. 385 MPa). This hard solid becomes soft again after transient heating, demonstrating the reversibility of the transition. This material, demonstrating distinct, interchangeable, and stable solid states (termed as a “two-in-one” solid), would be advantageous for several technological applications.
They will further apply this exploitation of the physical metastability of a liquid state to sugar alcohols, resulting in a second hybrid material: a stimuli-responsive and non-evaporating sug-gel. These “two-in-one” solid materials may find potential uses in soft robotics and adhesive applications.
Reference: Fut (Kuo) Yang, Aleksander Cholewinski, Li Yu, Geoffrey Rivers, and Boxin Zhao, “A Hybrid Material That Reversibly switches Between Two Stable Solid States”, Nature Materials, 18, 874–882, 2019