Smart polymers for the detection of polymeric contamination in fresh water

The feasibility of using reversible complexation between labelled poly(acrylic acid) and poly(acrylamide) as a low concentration detection method for industrial flocculants has been investigated. Aromatic labels acenaphthylene and 9-anthryl methyl methacrylate have been added to polymer chains to model the behaviour of these polymers in dilute aqueous solutions, demonstrating a molecular weight dependency of the conformational change of poly(acrylic acid). It is shown that interpolymer complexation can be observed via a dramatic rise in anisotropy of a singly labelled sample. Using a single exponential system to model the data a clear concentration gradient can be created, showing the ratio between probe polymer and detected species. This system is robust against a range of salts and other water impurities and other polymers capable of bonding to poly(acrylic acid) have also been investigated. Chains of poly(acrylic acid) were grafted onto solid surfaces in a preliminary investigation into whether it would be possible to integrate this detection system with a reusable solid substrate. Two methods were investigated: ceric ammonium nitrate initiated grafting and reversible addition-fragmentation chain transfer copolymerisation.