Nanoporous materials derived from polymeric bicontinuous microemulsions

A technique for the synthesis of nanoporous materials with uniformly sized pore networks on the order of 100 nm and with wide ranging chemistry was studied. PE and PEP homopolymers and a symmetric poly(ethylene-block-ethylene- alt-propylene) diblock copolymer were synthesized by anionic polymerization. The nanoporous PE monoliths were analyzed by scanning electron microscopy (SEM). Samples were prepared by submerging and fracturing small pieces cut from the monoliths in liquid nitrogen. The SANS data for the BμE (bicontinuous microemulsion) indicate an average domain spacing. The porosity of the material is 40%, evaluated by infiltrating the pores with the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)-imide and measuring the resultant change in weight. The results presented demonstrate that the structure of a BμE can be replicated with high precision in materials formed at both high and low temperatures, resulting in nanoporous materials with three-dimensionally continuous pore networks and pore sizes on the order of 100 nm.