Common types of cationic surfactants

Quaternary ammonium salts. Only the structure of the cation is shown. The most commonly used anions are Cl, Br, CH3COO and CH3OSO3, the last resulting from the use of dimethyl sulphate as a quaternising agent. Weak bases are shown in the deprotonated form the protonated form has the anion of whatever acid was used for protonation. 

Monoalkyltrimethylammonium salts Dialkyldimethylammonium salts Benzalkonium salts Alkylpyridinium salts 

Weak bases. These are often classified as nonionics they are cationic only in acid solution, and nonionic in neutral or alkaline solution. 

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