The fabrication of self-healing cellulose triacetate polymer composites and dicyclopentadine polymeric foam

Damage continues to plague the structural integrity of polymer composites. Continued stress leads to cracking and weakening of a composite system. Engineering polymer composites with carbon nanotube reinforcements and self-healing capabilities can potentially enhance the composites properties and extend the service lifetime. Carbon nanotubes (CNTs) promise to improve the electrical and mechanical properties of composite materials into which they are incorporated. These hollow tubes comprised completely of carbon, which have nanometer scale diameters, as well as low density, possess unique paradigm-shifting mechanical and electrical properties. The major problem prohibiting the widespread use of enhanced polymer composites has been the difficulty fabricating these composites. Research in developing methods capable of fully integrating the components is essential. This study sought to develop fabrication strategies to overcome the problem of integration and create polymer composites with advanced behavior useful in multiple applications.;Engineering polymer composites with CNT and self-healing capabilities could enhance the composites' properties and extend the lifetime. Polymer composites are prone to degradation and damage. The damage leads to major system failure. The strategy developed here was inspired by living systems that evolved to mend damage and regain function. Engineering "smart" synthetic composites with infrastructures which can respond to damage is necessary for improving polymer usefulness. The molecular processes that alleviates damage aids in avoiding total mechanical failure. Such self-healing materials repair damage and continue function post repair.;There several methods for creating composites with self-healing capability. The one studied here involves embedded microcapsules whose envelopes burst open releasing their contents in response to the material cracking. Microcapsules containing a reactive liquid "healing" core are embedded in the polymer during fabrication. A mechanical defect in the polymer breaks the shells of the microcapsules releasing the "healing" core. The core material polymerizes, thus healing the crack. As defects are repaired, functionality should be restored and the serviceable lifetime extended. The results obtained in this study indicate microcapsules can be modified to incorporate CNT. Also self-healing capabilities can be extended to new polymer systems in a cost-effective manner.;In addition to enhancing polymers for sustainability, CNT reinforced structural foams could also prove to be beneficial in numerous industrial applications, where mechanically strong foams are needed. CNTs are already being investigated as structural enhancements for other foams, such as polyurethane---the most common and widely used polymer. High internal phase emulsion foams, highly porous emulsion template foams, are emerging as new and important forms of microcellular foams with numerous advantages, such as high impact strength and high stiffness-to-weight ratio. This research developed a novel method for creating carbon nanotube reinforced microcellular foam.