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Design of Soft Material Surfaces with Rationally Tuned Water Diffusivity
Audra J DeStefano1, My Nguyen1, Glenn H Fredrickson1,2,3
1Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States.
ACS Central Science
|May 30, 2023
Summary
Researchers controlled water diffusion in polymer micelles using excluded volume. This allows tuning local water dynamics and solute activity at material interfaces.
Area of Science:
- Soft matter physics
- Polymer science
- Interface science
Background:
- Water structure and dynamics influence adsorption, separations, and reactions at soft material interfaces.
- Controlling water environments within functionalizable materials remains a challenge.
Purpose of the Study:
- To develop a method for systematically tuning water environments within a material platform.
- To control and measure water diffusivity as a function of position within polymeric micelles.
- To demonstrate rational design of polymer surfaces and local water dynamics.
Main Methods:
- Utilized sequence-defined polypeptoids to create a materials platform.
- Varied excluded volume to control water diffusivity.
- Employed Overhauser dynamic nuclear polarization (ODNP) spectroscopy to measure water diffusivity gradients.
Main Results:
- Successfully generated a water diffusivity gradient extending from the polymer micelle core.
- Demonstrated control over functional group positioning within the polypeptoid micelles.
- Showcased the ability to tune local water dynamics based on material design.
Conclusions:
- Sequence-defined polypeptoids provide a versatile platform for controlling interfacial water dynamics.
- This approach enables rational design of material surfaces and their local solute activity.
- The findings offer new avenues for designing advanced soft materials and interfaces.
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