Methyltrioctylammonium chloride, also known as trioctylmethylammonium chloride, is a halogenated quaternary ammonium salt. Quaternary ammonium salt is a class of cationic surfactants, of which halogenated quaternary ammonium salt (R1R2R3R4N+ChemicalbookX-) series compounds are widely used in daily chemical, textile, printing and dyeing, mining, asphalt, construction, plastic processing, oil exploitation, petrochemical and other fields, playing an important role.