Amyloid fibrils are a form of protein nanofiber that show promise as components of multifunctional bionanomaterials. In this work, native bovine insulin and bovine insulin that had been previously converted into amyloid fibrils were combined with poly(vinyl alcohol) (PVOH) via solution casting to determine the effect of fibrillization on the thermomechanical properties of the resulting composite. The synthesis method was found to preserve the amyloid fibril structure and properties of the resulting fibril-PVOH composite were investigated. At a filling level of 0.6 wt %, the fibril-reinforced PVOH was 15% stiffer than the PVOH control. Various properties of the films, including the glass transition temperature, degradation temperature, microstructure, and film morphology were characterized. Although more work is required to optimize the properties of the composites, this study provides proof of principle that incorporation of amyloid fibrils into a polymeric material can impart useful changes to the mechanical and morphological properties of the films. (c) 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2012