Submicron-scale exclusion via polymerizing an aromatic nylon in molded ceramic monolith for paving interconnected pore channels

Abstract

A matrix with extensively interconnected channels is an important feature to pursue ceramic membrane technology. This work attempts an alternative pore-forming strategy through utilizing in situ generated poly(p-phenylene terephthalamide) (PPTA) nanorods as a pore former. Different from the conventional means, this approach relies on interstice exclusion of the PPTA rods throughout the green ceramic object. The spatial confinement restricts the polymerization extent of PPTA, resulting in a localized generation of nanocrystallite rods and an expansion of interparticle contacts simultaneously. Another feature of this PPTA is the high carbonization degree of PPTA which allows for space retention of the rods during the initial stage of calcination designed to sinter the object. The pore channels left behind in the sintered article possess the throat-to-void structural characteristic. Besides the marked improvement on fluid permeability and mechanical strength over the ones fabricated by using starch as pore former, such a pore structure claims an unusual capability to induce a shear thinning effect when a pressure-driven dilute polymer solution passes through the channels. © 2010 The American Ceramic Society.