Robust antifogging coatings with ultra-fast self-healing performances through host-guest strategy

Abstract

Given the vulnerability of conventional antifogging coatings to mechanical damage, self-healing capability can significantly restore their functionality, but are difficult to materialize quickly and effectively. Herein, we report a facile UV-curable antifogging coating, based on host–guest interaction to obtain both ultra-fast self-healing performance and robust mechanical properties. Initially, a pair of host–guest supermolecules (HGSM) consisting of acrylic β-cyclodextrin (Aβ-CD) and acrylic adamantane (AAM) are synthesized and utilized as cross-linkers. Together with hydrophilic and hydrophobic moieties, 2-acrylamide-2-methylpropane sulfonic acid (AMPS) and methyl methacrylate (MMA), a robust antifogging coating with ultra-fast self-healing ability is developed via a facile UV curing process. Benefitting from the delicate balance of both hydrophilic and hydrophobic constituents, the resultant coatings display excellent antifogging performance with ∼90 % of light transmission, ranging from −20 °C to 85 °C. The unique non-covalent host–guest structure was covalently integrated into a cross-linked network, as-prepared coating and bulk gel exhibited ultra-fast self-healing capability, needing only ∼15 s to completely heal the cracks under the hot-steam environment (85 °C). And the bulk gels with host–guest recognition can significantly improve its self-healing efficiency to ∼88.3 %, significantly greater than its H-bonding counterpart (43.5 %). Notably, the prepared coating with strong adhesion properties (∼431 KPa) is robust enough to withstand 1,000 cycles of abrasion and 2 h of water immersion to maintain excellent antifogging performance. This strategy might open new avenues for accelerating the use of host–guest assembly to rapidly build effective antifogging/self-healing coatings and promote their applications in more harsh fogging conditions.