Gas-phase surface esterification of cellulose microfibrils and whiskers.

摘要: A new and highly efficient synthetic method has been developed for the surface esterification of model cellulosic substrates high crystallinity accessibility, namely, freeze-dried tunicin whiskers bacterial cellulose microfibrils dried by critical point method. The reaction, which is based on gas-phase action palmitoyl chloride, was monitored solid-state CP-MAS 13C NMR. It found that grafting density not only depended experimental conditions, but also nature conditioning samples. structural morphological modifications at various degrees were revealed scanning electron microscopy X-ray diffraction analysis. These characterizations indicated proceeded from substrate to their crystalline core. Hence, moderate degree substitution, fully grafted whereas core remained unmodified original fibrous morphology maintai...