Solid tethered imino-bis-propanediol and quaternary amine functional copolymer brushes for rapid extraction of trace boron

A synthesis strategy is described for designing new, more efficient and reusable boron specific resin material which is able to remove trace boron from aqueous solutions within less than a minute. This strategy involves generation of dense N-vinyl formamide (NVF)-diallyldimethylammonium chloride (DADMAC) copolymer brushes (up to 1510% w/w) on PS-DVB (10%) microspheres by surface initiated polymerization (SIP) of the monomer mixture from dithiocarbamate surface groups, using photo-iniferter technique. Hydrolysis of the formamido groups and followed reaction with glycidol yield hairy grafts with boron chelating imino-bis-propanediol (IBP) functions and chain expanding quaternary amino groups. Experiments revealed that, the materials built up of hairy grafts with 0%, 10% and 20% of DADMAC contents show boron loading capacities 2.9-4.0mmolg^-1, the latter being the highest capacity reported so far. Moreover the increasing DADMAC content provides even faster boron uptakes from non-buffered solutions. New boron chelating resins presented seem to be promising for practical uses, due to their easy regeneration with 10% HCl and unchanged boron sorption capacities after 10 times of recycling.