Megan Robertson, University of Houston A great challenge to overcome is the replacement of traditional petroleum-based plastics with polymers derived from sustainable, alternative resources. Though there are many facets to the design of truly sustainable materials, including the raw material source, energy demands of processing, and fate of the material post-consumer use, utilization of a more eco-friendly raw material source is an important first step. Ultimately, the full life cycle of the materials must be evaluated, including end-of-life options such as recycling, composting, and disposal in landfills. Of particular interest is the design of structured polymers from sustainable, plant-derived sources with well-defined molecular characteristics and competitive properties to conventional, petroleum-derived materials. Vegetable oils are an attractive source for polymers, due to their low cost, abundance, annual renewability, and ease of functionalization. Long-chain polyacrylates derived from vegetable oil-based fatty acids were investigated as components of thermoplastic elastomers, polymers which behave as an elastomer at room temperature yet are processable at elevated temperatures. The thermal and mechanical behavior of the polymers was readily tuned through variation of the alkyl side-chain length of the polyacrylate. Surprisingly, the alkyl side-chain length did not impact the thermodynamic interactions between the components of the thermoplastic elastomers. This provides a route to manipulating the physical properties of the polymers through variation of the side-chain length without impacting the phase behavior and morphology. The development of structure-property relationships in these polymers will enable the widespread implementation of fatty-acid derived materials.