In the present research, we discuss the influence of a hydrophobic modifier on the properties of cellulose fibers. The commercially available fluorocarbon polymer water dispersion was introduced in different concentration ratios to the spinning dope to change the physical properties of cellulose fibers. Cellulose fibers from N-methyhnorpholine-N-oxide were prepared as a direct solvent. The fibers obtained contained up to 15% w/w of fluorocarbon polymer. To observe how the modifier influences the fibers' mechanical and thermal properties, fibrillation tendency and moisture absorption were examined. (c) 2007 Wiley Periodicals, Inc.