A stock solution ('ATRP cocktail') containing the monomer (SPMAK), copper halide salt (CuCl2), and ligand (BiPy) in 4:1 water to methanol is prepared. The concentrations are systematically varied to determine optimal condictions as described in the results section. Another stock solution of 50 mM ascorbic acid in water is made. The latter solution has to be prepared fresh daily unless stored under anaerobic conditions, since aqueous solutions of ascorbic acid are not stable in aerobic conditions.