Trimethylsilylcellulose/Polystyrene Blends as a Means To Construct Cellulose Domains on Cellulose

Abstract

A method to prepare films of conspicuous domains of cellulose on a closed cellulose layer is introduced. These films can be used as model surfaces which are closer to the natural environment than most organic model surfaces that are usually coated directly on an inorganic substrate. The method is based on spin-coating a hydrophobic derivative of cellulose, trimethylsilylcellulose (TMSC), blended with polystyrene (PS) onto a silicon substrate. TMSC can be hydrolyzed to cellulose with acid hydrolysis, leaving domains of cellulose and PS embedded on a sublayer of cellulose. Selective dissolving of PS leaves a closed cellulose surface (sublayer) with eminent cellulose domains whose size depends on the original TMSC/PS ratio. The chemistry of the films was analyzed with X-ray photoelectron spectroscopy (XPS) and the morphology with atomic force microscopy (AFM). Scrutiny of the AFM data showed that the films are quantifiable and quantitatively reproducible.