4.3 MC and MHPC: chemistry and properties To prepare MC, alkali cellulose is formed by steeping cellulose sheets or chips in caustic, by spraying caustic onto cellulose fibre, by slurrying cellu-lose in aqueous caustic and pressing out the excess, or by mixing cellulose with aqueous caustic and an inert solvent (Greminger and Krumel, 1980). The alkali cellulose is reacted with methyl chloride in accordance with the Williamson etherification reaction at elevated temperature, 50-100°C, and up to 14kg/cm2 pressure for several hours (Greminger and Krumel, 1980):
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