A shape memory porous sponge with tunability in both surface wettability and pore size for smart molecule release

Recently, smart superwetting porous materials have aroused much attention, and it is well known that tunable surface wettability and pore structure/size are extremely important for their functions. However, only one factor can be regulated on existing materials, which significantly restricts their controllability, functions, and applications. A new material was prepared by electrodepositing a layer of polypyrrole on a shape memory sponge, on which switchable superhydrophobicity/superhydrophilicity and adjustable pore size within the range of about 28 nm to 895 µm can be observed. Through synergistically tuning the wettability and pore size, both ON/OFF water permeation and accurate flux can be obtained. Meanwhile, we also applied the sponge for molecule release, and diverse release manners with precise/smart controllability can be accomplished. This paper reports for the first time a smart material with controllability in both surface wetting and pore size, which provides a new strategy for the preparation of novel smart superwetting porous materials.