Keratin obtained from poultry feathers was modified with glycerol, which acted as a plasticizer. Films were prepared by pressing the modified keratin at temperatures concurrent with typical polymer processing temperatures. The films were completely cohesive as opposed to partially cohesive if pressed under the same conditions without glycerol. The films were "tough" and the mechanical properties show similarities to the properties of commercially available commodity thermoplastics. The keratin films were produced in a few minutes without reducing or oxidizing agents. The keratin films could have potential applications for which environmentally friendly materials are needed, such as food packaging or mulching films. (c) 2005 Wiley Periodicals, Inc.