Ultrastretchable Graphene-Based Molecular Barriers for Chemical Protection, Detection, and Actuation

A wide
range of technologies requires barrier films to impede molecular
transport between the external environment and a desired internal
microclimate. Adding stretchability to barrier films would enable
the applications in packaging, textiles, and flexible devices, but
classical barrier materials utilize dense, ordered molecular architectures
that easily fracture under small tensile strain. Here, we show that
textured graphene-based coatings can serve as ultrastretchable molecular
barriers expandable to 1500% areal strain through programmed unfolding
that mimics the elasticity of polymers. These coatings retain barrier
function under large deformation and can be conformally applied to
planar or curved surfaces, where they are washfast and mechanically
robust to cycling. These graphene–polymer bilayer structures
also function as sensors or actuators by transducing chemical stimuli
into mechanical deformation and electrical resistance change through
asymmetric polymer swelling. These results may enable multifunctional
fabrics that integrate chemical protection, sensing, and actuation,
with further applications as selective barriers, membranes, stretchable
electronics, or soft robotics.