A fluffy all-siloxane bottlebrush architecture for liquid-like slippery surfaces

Abstract

Surfaces with special wettabilities play a crucial role in numerous applications. Slippery surfaces, known for their low adhesive properties and efficient self-cleaning capabilities, have gained significant attention. However, the existing liquid-like slippery surfaces are limited to linear molecular structures, which hinders the new design and functionalization of the slippery surfaces. In this study, we present a novel fluffy all-siloxane bottlebrush molecular architecture that enables the construction of liquid-like slippery surfaces through a simple sequential architecting method. This unique structure, consisting of soft polysiloxanes as both backbones and side chains, enhances surface slipperiness via the in situ condensation of dimethoxy-silanes and subsequent hydrosilylation reaction on the substrate. The multiplied surface grafting density significantly improves the sliding properties, resulting in the first non-linear liquid-like slippery surfaces. These surfaces exhibit reduced contact angle hysteresis, outperforming their linear counterparts. Furthermore, the integration of low adhesion, broadband optical transparency, and the ultra-thin and smooth nature of these slippery surfaces has demonstrated outstanding potential in many important applications, such as anti-icing, contamination resistance and optoelectronic devices, even in challenging environmental conditions.