Hierarchical Sponge‐Hydrogel Hybrid Structures with Robust Interfaces^†

Abstract

Comprehensive SummarySoft materials including elastomers and hydrogels are playing critical roles in a variety of fields, including bioelectrodes, batteries, supercapacitors, biomedical scaffolds, and solar vapor absorbents. Integrating hydrophobic sponges (i.e., mechanical robustness, elasticity and macroscopic porous structure) and hydrophilic hydrogels (i.e., autonomous water absorption and transportation, biocompatibility) within one unit could readily combine the complementary characters from each component, making a number of future research directions and applications possible. We propose a simple yet effective strategy to construct sponge‐hydrogel hybrid structures with robust hydrophobic‐hydrophilic interface. The sponge scaffold imparts the sponges‐hydrogel hybrids with desirable mechanical robustness, elasticity and macroscopic pores. On the other hand, the incorporated hydrogel component endows the hybrids with high water content (98 wt% hydrogel and 2 wt% sponge), superior compatibility, and nanoscale pores allowing for storage and transportation of various chemical and biological molecules. We further demonstrate that the introduction of hydrophilic hydrogel components could effectively improve the liquid absorption capability, blood coagulation rate, hemostatic capacity and hemocompatibility, thus promising as hemostatic agents.

Hydrophilic amphibious open-cell macroporous sponge by Hofmeister effect induced nanofibrils

“…4,5 A marvelous feature of these hydrophilic sponges is their absorption of huge amounts of water while keeping their shapes, despite the tiny mass of the solid scaffold of sponges. 6 Many researchers have developed various kinds of hydrophilic sponges using polymers including polyimide, 7 polyurethane, 8 polymethyl methacrylate, 5,9 poly ( N -isopropylacrylamide) 10,11 and poly(vinyl alcohol) (PVA). 12 However, a simple and low carbon route to prepare the hydrophilic sponge is still lacking.…”