(511d) Synthesis of Renewable and Degradable Block Polymers | AIChE

(511d) Synthesis of Renewable and Degradable Block Polymers



Block copolymers with the ABA triblock architecture are useful as thermoplastic elastomers and as toughened plastics depending on the relative content of the glassy and rubbery components. These materials can also be blended with other materials and find commercial utility as additives, toughening agents, compatibilizers, and pressure sensitive adhesive formulations. Nearly all of the block copolymers currently on the market are derived from petroleum. Renewable alternatives are attractive considering the finite supply of fossil resources harbored by Earth, the overall economic and environmental cost associated with the recovery and use of oil. Furthermore, the design and implementation of materials with programmed end-of-life is an attractive approach to tomorrow’s sustainable materials. With these motivations on board, we have focused our attention on the preparation and evaluation of new classes of renewable ABA triblock copolymers and other, architecturally more complex hybrid materials. We have emphasized the use of carbohydrate-derived polylactide as the high glass transition temperature and/or high melting temperature hard phase given its widespread availability and acceptance. For the soft components, we have focused on other renewable, low glass transition, amorphous aliphatic polyesters and hydrocarbon polymers. In this talk I will highlight our synthetic strategies to linear and graft copolymers containing polylactide as both the major and minor component. In several cases, the combination of multiple controlled polymerization mechanisms has proven to be a powerful enabling approach. Precision synthesis of these new hybrid macromolecules combined with detailed molecular and morphological characterization has lead to the development of new elastomers and tough plastics that marry renewability, biodegradation and performance.