Date of Award
Chemistry and Biochemistry
Mohammed J. Ahamed
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
Herein, an intrinsic autonomous self-healing polymer system has been developed and explored leading to new materials that are easily able to be fine-tuned both mechanically and chemically. Through an easy condensation reaction, the system explored incorporates dynamic and reversible bonds within polydimethylsiloxane monomer chains, namely dynamic imine and metal-coordinated bonds, to enable autonomous self-healing while also allowing for simple alteration of the system through manipulation of the metal salt used to coordinate the ligands of the monomer units. In addition to the autonomous self-healing of the system, controlled degradability at mild pH and ultra-high stretchability (up to 800% strain) are possible through alteration of the metal to ligand ratio and type of metal used in the coordination. Characterization of this dynamic system was performed through a variety of techniques such as tensile-pull strain testing, atomic force microscopy, UV-Vis spectroscopy, dynamic mechanical analysis, and shear rheology which showed that the highly dynamic imine bonds combined with the coordination with various transition metal salts allowed for the material to regenerate up to 88 % of its mechanical strength after physical damage while also being able to generate materials that ranged in their Young’s modulus from approximately 0.2 MPa to 10 MPa through simply altering the bonds formed through the metal ligand coordination interaction. Results suggest the mechanical properties of the system under investigation is directly related to its ability to regenerate upon damage. The new soft polymer has also been used as a dielectric layer in a capacitive based pressure sensor that is able to regenerate its mechanical and electrical properties upon damage, proving the possibility of our self-healing polymer for use in the next generation of self-healing electronics.
Pignanelli, Julia, "Development of A Robust, Soft and Flexible Selfhealing Polymer Based on Dynamic Coordinate Metallig and Bonds" (2020). Electronic Theses and Dissertations. 8388.