Synthesis and scale-up of water-soluble quaternary cationic monomers in a continuous flow system

A continuous flow technology was developed for the synthesis and scale-up of water-soluble quaternary cationic monomers represented by dimethyldiallylammonium chloride (DMDAAC) in a self-designed reactor. For industrial applications, static mixers were employed in a self-designed scaled-up reactor to maintain the mass and heat transfer rates from microfluidics to mesofluidics during the scale-up. Three different types of static mixers were investigated, and their optimal combination was determined. Various factors including the reaction temperature, fluid rate, and reagent concentration were also investigated in detail. This work increased the yield up to 92% under optimal conditions with an output of one kiloton per year. Moreover, this proposed method exhibited excellent performance in the synthesis and scale-up of other water-soluble quaternary cationic monomers in a continuous flow system.