4. ConclusionsThe main purpose of this study was to reduce CNFs’ hydrophiliccharacter and thus improve their compatibility with commonnon-polar polymeric matrices. Some conclusions of chemical mod-ification of CNFs are as follows:(a) FT-IR results displayed a successful acetylation of CNFs.(b) The dispersion of CNFs in non-aqueous mediums (acetone andethanol) showed that the hydrophobicity of the acetylatedCNFs significantly increased compared to the non-acetylatednanofibers.(c) X-ray analysis revealed that the acetylation process reduced thecrystallinity of the cellulose chains.(d) TGA results revealed that the thermal stability of modified CNFswas moderately increased.(e) The contact angle measurements indicated that the acetylationtreatment changed the surface characteristics of the CNFs fromhydrophilic to more hydrophobic.(f) The SEM study showed that the surfaces of the acetylatednanofibers were slightly rough, while the non-acetylatednanofibers had smooth and uniform surfaces.(g) Finally, it is concluded that the esterification reaction usingpyridine as catalyst was efficient and could be considered as afacile method to modify the surface of nanofibers, which opensup a new opportunity for using CNFs as reinforcement in non-polar polymer matrices.