| The main goal of this work is to investigate mechanical behavior and develop rheological characterization methods of complex construction materials. It aims to improve on already existing construction materials, such as gypsum board and joint compounds. Creating a more advanced gypsum board typically means either making it stronger, more flexible, or less dense; whereas enhancing joint compounds typically means it is easier to apply to the wall.;The creation of self-healing core-shell nanofibers was the first step in developing a material that is still usable after it fails. Furthermore, creating the fibers from a multitude of ways will give manufacturers flexibility in making these fibers. Therefore, self-healing core-shell fibers were created using three techniques, namely: emulsion electrospinning, coelectrospinning, and solution blowing. Each technique has its advantages and disadvantages which are discussed, but all are more economically viable and easier to incorporate into large scale manufacturing than techniques used by other researchers (also given the fact that the other groups did not develop nano-scale self-healing materials). The main mechanism that allows the fibers to heal the bulk material is that a slightly porous and weak (compared to the bulk material) fiber shell encapsulates a liquid healing agent. When the bulk material is stressed beyond a defined point, the fiber shell fails and the liquid core material is released due to the applied stress. The core material will polymerize in the fractured zone in contact with a preliminary dispersed/present catalyst, essentially healing the fractured area. The core material can be chosen to polymerize either when it makes contact with another material in the bulk, similar to Grubb's catalyst, or when it makes contact with the humidity in the air. Evidence was collected that reveals the core material exits the shell in multiple ways and polymerizes when being released. (Abstract shortened by UMI.). |
