Improving Thin-Film Properties of Poly(vinyl alcohol) by the Addition of Low-Weight Percentages of Cellulose Nanocrystals.

The increased demand for electronic devices, combined with a desire to minimize the environmental impact, necessitates the development of new eco-friendly materials. One promising approach is the incorporation of renewable and green materials that possess the desired mechanical and electrical properties while allowing for more ecologically friendly disposal of these devices. The addition of low-weight percentages (0.25-0.75 wt %) of cellulose nanocrystals (CNCs) was investigated as an environmentally friendly additive in aqueous dispersions of poly(vinyl alcohol) (PVA). It was found that these low CNC loadings were sufficient to induce a favorable increase in viscosity, which in turn dramatically enhanced the film quality of the PVA blends through an improvement in the critical radius of the spun film, overall film thickness, and homogeneity of the thin film. This corresponded to an increase in the number of functioning organic electronic devices that could be fabricated by spin coating, including metal-insulator-metal (MIM) capacitors and organic thin-film transistors (OTFTs). Most importantly, the incorporation of CNCs into PVA did not significantly alter the native dielectric properties of the polymer thin films when incorporated into both MIM capacitors and OTFTs.