Diffusion and Flow Across Nanoporous Polydicyclopentadiene-Based Membranes

We report gas and liquid tranport measurements through membranes that have 40% voids made of 14 nm pores. a reactive polylactide-polynorborneenylethylstyrene block polymer is used as a structural template in the polymerization of dicyclopentadiene during the membrane formation process. After the membrane is cast, the pore structure is formed by etching the polylactide component using dilute aqueous base. The pore structure is isotropic therefore, therefore, there is no need for special alignment techniques Knudsen diffusion experiments and water flow experiments show pores with a tortuosity of 1.81 and a size of 14 nm, a diameter consistent with nitrogen adsorption and small angle X-ray scattering measurements. These membranes are effective for ultrafiltration, tuned by changing the size of the constituent blocks in the templating copolymer.