Smart Gating Membranes with Responsive Nanogels as Functional Gates

Smart gating membranes, as emerging artificial biomimetic membranes, have the ability to self-adjust their permeable and separative features in response to stimuli from the environment. Until now, the simple creation of smart or intelligent gating membranes possessing synchronous large flux, and strong mechanical strength as well as significant responsive characteristics was thought to be very challenging. In this chapter, a new strategy for the easy and controllable production of satisfactorily-performing smart gating membranes, through the construction of response nanogels in situ in the surfaces of membrane pores by virtue of a vapor-induced phase separation process, is designed and developed. Taking poly(N-isopropylacrylamide) (PNIPAM) nanogels as functional gates, the available thermo-responsive smart membranes exhibit large flux, an excellent mechanical property and significant thermo-responsive characteristics simultaneously. Meanwhile, the resultant novel thermo-responsive catalytic membranes with silver-nanoparticle-loaded PNIPAM nanogels as thermo-responsive gates and catalysts show both satisfactory thermo-responsive characteristics and catalytic properties. Such catalytic membranes are able to adjust the throughput in light of the feed reactant concentration and maintain high catalytic conversion in the meantime through alteration of the reaction temperature. The outcomes offer valuable instructions for the design and production or even high-volume manufacture of smart membranes with an expected performance. The new strategy suggested is applicable to producing diverse functional materials with pores modified by responsive or non-responsive nanoparticles in diverse utilizations.