Functionalized Nanoporous Membranes from Reactive Triblock Polymers

Hydrophilic and stimuli responsive nanoporous poly(dicyclopentadiene) membranes are prepared using reactive ABC triblock polymers consisting of a chemically etchable 'A' block, poly(lactide), various functionalized 'B' blocks, and a metathesis-reactive 'C' block, poly(styrene-stat-norbornenylethylstyrene). A membrane with a bicontinuous structure is formed by reaction-induced phase separation during the metathesis crosslinking of dicyclopentadiene in the presence of the ABC triblock polymers. Selective etching of the poly(lactide) block exposed the functionality contained in the B block. Hydrophilic membranes are prepared from a triblock polymer with a poly(N, N-dimethylacrylamide) B midblock as evidenced by static contact angle measurements in comparison to AC diblock templated membranes. Temperature responsive membranes are prepared from a triblock polymer with a poly(N-isopropylacrylamide) B block.