US Patent 11253819 Production of thin film composite hollow fiber membranes

System, devices, and method for the production of thin film composite hollow fiber membranes on a hollow fiber support structure. The system includes a comb and roller device, or comb and dual roller device, which can be used to define a submerged travel path in a first solution bath for a hollow fiber. The combs and rollers control the amount of time the hollow fiber spends in the first solution. The first solution contains a first monomer, and the hollow fiber is impregnated with the first monomer. The amount of impregnation depends on the time spent in the first solution. Subsequent immersion in a second solution containing a second monomer results in the formation of a thin film composite hollow fiber membrane.