| 초록 |
In recent years, cellulose materials have attracted significant attention because of their excellent structural stability as well as abundance in nature. This study synthesizes hydrophobically associative cellulose nanofibers by using combined ATRP and 2,2,6,6-tetramethylpiperidine-1-oxyl radical(TEMPO)-mediated oxidation. Specifically, cellulose nanocrystals are functionalized by partial esterification of superficial -OH groups with 2-bromoisobutyryl bromide to introduce initiation sites. Then, these initiation sites-functionalized cellulose nanocrystals are grafted with stearyl methacrylate and 2-methacryloxyethyl phosphorylcholine by ATRP. Finally, the TEMPO-mediated oxidation enables production of nanoscale cellulose nanofibers. We have found that the cellulose nanofibers can not only dramatically increases the viscosity of aqueous solution due to the hydrophobic attraction, but also display excellent tolerance to pH changes and salt addition due to the gel phase formation. We expect the cellulose nanofibers developed in this study would find great applicability as suspension rheology modifiers. |
