Substituent Distribution in Cellulose Acetates: Its Control and the Effect on Structure Formation in Solution
1Institute for Chemical Research, Kyoto University, Uji, Kyoto, 611-0011, Japan
Abstract:
Architecture-regulated cellulose derivatives were prepared by regioselective substitution of C-2, -3, and -6 position hydroxyls in cellulose by O-acetyls or trityls. Their dynamic structures formed in polar solvents were compared with those by the commercial cellulose acetates where the distribution of hydroxyls and O-acetyls was nearly random in the chain. It was found that the difference in the chain architecture induces a large difference in the chain conformation, the solubility, and the clustering mechanism and structures; i.e., they changed with solvent quality, concentration, temperature, strength of external field, and so on. Copyright 2000 Academic Press.
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