HIERARCHICALLY POROUS POLYMERIC MATERIALS FROM TERNARY POLYMER BLENDS

摘要

Hierarchically porous polymeric materials with controllable pore size were successfully generated through a ternary polymer blending strategy. Polylactide/high-density polyethylene/styrene-ethylene/butylene-styrene copolymer (PLA/HDPE/SEBS) was used as a model system to demonstrate this technique. After melt blending, the SEBS was driven into the HDPE phase owing to the presence of the PE block in the copolymer. With proper volume fractions of HDPE/PLA/SEBS (e.g., 25/50/25), a bi-modal, dual co-continuous morphology was obtained and hierarchically porous polymeric materials were further generated by selectively removing the PLA and SEBS phases. Annealing and composition variation were further employed to control the pore size and it is shown that the length scales, for each of the two co-continuous morphologies, can be controlled independently.