Adaptive and freeze-tolerant heteronetwork organohydrogels with enhanced mechanical stability over a wide temperature range

Abstract

Many biological organisms with exceptional freezing tolerance can resist the damages to cells from extra-/intracellular ice crystals and thus maintain their mechanical stability at subzero temperatures. Inspired by the freezing tolerance mechanisms found in nature, here we report a strategy of combining hydrophilic/oleophilic heteronetworks to produce self-adaptive, freeze-tolerant and mechanically stable organohydrogels. The organohydrogels can simultaneously use water and oil as a dispersion medium, and quickly switch between hydrogel- and organogel-like behaviours in response to the nature of the surrounding phase. Accordingly, their surfaces display unusual adaptive dual superlyophobic in oil/water system (that is, they are superhydrophobic under oil and superoleophobic under water). Moreover, the organogel component can inhibit the ice crystallization of the hydrogel component, thus enhancing the mechanical stability of organohydrogel over a wide temperature range (−78 to 80 °C). The organohydrogels may have promising applications in complex and harsh environments.

Highly Stretchable and Tough Hydrogels below Water Freezing Temperature

“…[9] However, in all these applications, the hydrogels lose their desirable properties once the temperature decreases below the freezing point of water, severely limiting their use in this temperature range. [10] There are concerns, however, about the environmental impact and health hazard as a result of the toxicity of these liquids. [10] There are concerns, however, about the environmental impact and health hazard as a result of the toxicity of these liquids.…”

Rational Fabrication of Anti‐Freezing, Non‐Drying Tough Organohydrogels by One‐Pot Solvent Displacement

“…Inspired by cryoprotectants (CPAs) used in the inhibition of the icing of water in biological samples,aversatile and straightforwardmethod is reported to fabricate extreme anti-freezing,n on-drying CPA-based organohydrogels with long-term stability by partially displacing water molecules within the pre-fabricated hydrogels.C PAbased Ca-alginate/polyacrylamide (PAAm) tough hydrogels were successfully fabricated with glycerol, glycol, and sorbitol. [13] Besides,L iu and co-workers applied aw ater/ethylene glycol binary solvent as the dispersion medium to fabricate antifreezing conductive organohydrogels in the temperature range from À55.0 to 44.6 8 8C. [1][2][3][4] To date,n umerous advances about hydrogels have been made,i ncluding the synthesis,a pplication, and engineering of various hydrogels.…”

“…[1][2][3][4] To date,n umerous advances about hydrogels have been made,i ncluding the synthesis,a pplication, and engineering of various hydrogels. [13] Besides,L iu and co-workers applied aw ater/ethylene glycol binary solvent as the dispersion medium to fabricate antifreezing conductive organohydrogels in the temperature range from À55.0 to 44.6 8 8C. Recently,s everal remarkable efforts were made to address the above two flaws.For example,Liu and co-workers reported the use of water and oil as the dispersion medium to fabricate adaptive and freeze-tolerant hetero-network organohydrogels,w hich inhibited the ice crystallization of the hydrogel components,leading to enhanced mechanical properties over aw ide temperature range from À78 to 80 8 8C.…”

Recent Advances in Bioinspired Gel Surfaces with Superwettability and Special Adhesion

“…a) Hierarchical macromolecule-nanoclay hydrogels with robust underwater superoleophobicity. [56] Copyright 2017, Nature Publishing Group. [39] Copyright 2010, John Wiley & Sons, Inc. b) Composite hydrogel coating with robust underwater superoleophobicity, low oil-adhesion, and excellent mechanical properties.…”