Facile synthesis of highly hydrophobic cellulose nanoparticles through post-esterification microfluidization

Abstract

A post-esterifcation with a high degree of substitution (hDS) mechanical treatment (Pe(hDS)M) approach was used for the production of highly hydrophobic cellulose nanoparticles (CNPs). The process has the advantages of substantially reducing the mechanical energy input for the production of CNPs and avoiding CNP aggregation through drying or solvent exchange. A conventional esterifcation reaction was carried out using a mixture of acetic anhydride, acetic acid, and concentrated sulfuric acid, but at temperatures of 60–85 ◦C. The successful hDS esterifcation of bleached eucalyptus kraft pulp fbers was confrmed by a variety of techniques, such as Fourier transform infrared (FTIR), solid state ¹³C NMR, X-ray photoelectron spectroscopy (XPS), elemental analyses, and X-ray diffraction (XRD). The CNP morphology and size were examined by atomic force microscopy (AFM) as well as dynamic light scattering. The hydrophobicity of the PeM-CNP was confrmed by the redispersion of freeze-dried CNPs into organic solvents and water contact-angle measurements. Finally, the partial conversion of cellulose I to cellulose II through esterifcation improved PeM-CNP thermal stability

Citation

Lin, Chunxiang; Ma, Qianli; Su, Qiaoquan; Bian, Huiyang; Zhu, J.Y. 2018. Facile synthesis of highly hydrophobic cellulose nanoparticles through post-esterification microfluidization. Fibers. 6(22): 1-14.