Gradient Copolymerization towards High-performance Monocomponent Polymers for Energy and Charge Storages
Abstract Polymers with excellent dielectric and electret capabilities are crucial for energy storage films, organic electronics and environmental filtrations. Nanocomposites is an emerging effective method, but the characteristics of complicated preparation, poor uniformity and high cost restrict its massive and practical applications. Here, we propose a gradient copolymerization strategy with controllable micro-phase interfaces for dielectric capability modulation, and gradient ethylene-styrene copolymer (PESt) exhibits extraordinarily enhanced dielectric, electrical insulating and electret properties against polyethylene and polystyrene. PESt exhibits a dielectric energy density towards 23 J·cm− 3, far exceeding commercially applied polymers and is comparable to nano-composites. By applying PESt as electret layer in organic field-effect transistors, largely enhanced memory window, optimized stability and field-effect mobility over 27 cm2·V− 1·s− 1 are achieved. Finally, PESt electret is employed in environmental filtrations with 20% enhancement in filtration efficiency. The simplicity and processability of gradient copolymerization against nano-composite, further suggest its potential in designing high-performance dielectric/electret polymers.
