High Dielectric Nonpolar Interfacial Layers Derived from Nanocellulose for Electrowetting Devices

A dielectric material is a particular type of insulator that does not conduct electricity but gets polarized when subjected to electricity, which is a crucial part of electronics such as cables, capacitors, displays, transformers, etc. Currently, synthesizing a nonpolar dielectric remains challenging. In this study, a method to make a high dielectric and nonpolar fluoropolymer and its nanocomposites based on cellulose nanocrystals (CNCs) by grafting it with nonpolar polymer 2,2,2‐trifluoroethyl methacrylate is reported. A high dielectric constant but nonpolar nanocellulose material is obtained for the first time. This material has an anisotropic arrangement of dipoles with a high polarizability effect, thereby displaying excellent dielectric properties (e.g., dielectric constant and loss: 8.59 and 0.017 at 10 kHz) and high stability (dielectric constant at 8.21 at 1 MHz). The dielectric material is miscible as an additive with other commercial fluoropolymer plastic, which demonstrates a high breakage voltage ranging from 4.6 to 9.2 kV/0.1 mm. When it is used as an interfacial layer in electrowetting display devices, it also demonstrated a low voltage driven and fast‐response effect. The excellent dielectric performances allow to develop more high‐performance dielectrics and electronics such as memories, sensors, actuators, wires, and film capacitors. Synthesis of organic nonpolar dielectrics with a well‐designed anisotropic nanostructure with high polarity/polarizability effect is reported. this new type of material shows good electrical properties including 1) excellent dielectric constant (e.g., dielectric constant and loss are 8.59 and 0.0179 at 1 kHz) and high stability at high applied electrical frequencies that guarantee its use in various electronic devices.