The present work deals with the effects of structural variables of celluloses on their dissolution in the solvent system LiCl/N,N-dimethylacetamide, LiCl/DMAc. Celluloses from fast growing sources (sisal and linters), as well as microcrystalline cellulose (avicel PH-101) were studied. The following structural variables were investigated: index of crystallinity, I(c); crystallite size; polymer porosity; and degree of polymerization determined by viscosity, DPv. Mercerization of fibrous celluloses was found to decrease DPv, I(c), the specific surface area, and the ratio pore volume/radius. The relevance of the structural properties of cellulose to its dissolution is discussed. Rate constants and activation parameters of cellulose decrystallization, prior to its solubilization, have been determined under nonisothermal conditions. The kinetic parameters calculated showed that dissolution is accompanied with small, negative enthalpy and a large, negative entropy of activation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.