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The production of MHEC involves several steps, starting with the modification of cellulose. Natural cellulose, derived from wood pulp or cotton, undergoes etherification in the presence of methylating and hydroxyethylating agents. The reaction leads to the formation of methyl and hydroxyethyl groups on the cellulose backbone, resulting in the final product, methyl hydroxyethyl cellulose.
One of the most pronounced differences between HEC and HPMC lies in their rheological properties. HEC tends to yield solutions that are less viscous compared to those derived from HPMC at equivalent concentrations. This is particularly beneficial in applications where a lighter texture is preferred. Additionally, HPMC solutions exhibit a more pronounced pseudoplastic behavior, meaning they can become less viscous under shear, making them suitable for applications requiring a smooth flow — such as in medicinal suspensions or topical formulations.
hec vs hpmc
