Modified cellulose flocculant—etherification reaction (2)

(1) One-step method

The one-step method is developed on the basis of some classic reactions of cellulose etherification reaction (such as Williamson etherification reaction, base-catalyzed alkoxylation reaction, base-catalyzed addition reaction, etc.

But in fact, the following two categories are commonly used

①Epoxy-type side group reaction Epoxy-type cationic monomer uses water (with or without organic solvents such as ethanol , propanol, etc.

②SN2 substitution reaction quaternary ammonium cationic monomer uses water (with or without organic solvents such as ethanol, isopropanol, etc.

(2) Step-by-step method

Feng Lin of Southwest Petroleum Institute used a stepwise method to prepare CMC cationized derivatives: using the carboxymethyl cellulose carboxymethyl cellulose group to esterify first with methanol, then Mannich reaction with N-carboxymethylamine, and finally Alkylation yields cationized carboxymethyl cellulose

①Example 1: Preparation of carboxymethyl cellulose quaternary ammonium salt

Jiang Gangbiao et al.

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b.

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②Example 2: Preparation of amphoteric polymer TOPCMC

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b.

③Example 3: Quaternization of anionic carboxymethyl cellulose

Zhang Liming et al

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