Cellulose model surfaces - simplified preparation by spin coating and characterization by X-ray photoelectron spectroscopy, infrared spectroscopy, and atomic force microscopy

Spin coating is introduced as a simplified method to prep. model surfaces of cellulose. Prior to spin coating, trimethylsilyl cellulose (TMSC), a nonpolar deriv. of cellulose, is synthesized in order to dissolve the otherwise immiscible cellulose. After the spin coating deposition of TMSC on an untreated Si or Au substrate, the TMSC layer is subjected to vapor phase acid hydrolysis, which regenerates it back to cellulose. XPS and attenuated total reflectance IR spectroscopy (ATR-IR) revealed the films' chem. structure to be similar to pure cellulose. Spin coating parameters, e.g. spinning speed, concn. of the coating soln., and nature of the solvent, were varied to obtain diversity in morphol. and thickness of the films. The optimal spin coating parameters resulted in a cellulose film with 20 nm thickness and 10% roughness, detd. by at. force microscopy (AFM). Preliminary expts. with modifying the chem. and varying the water content of the films were also conducted.