Slow release of water-soluble salts from polymers

Release rates of NaCl and NaF from mixtures with polystyrene, polyethylene, thermosetting polyester, and crosslinked polyethylene have been studied. Salt/polymer granules were prepared by melt mixing under different conditions. The release process was studied in batch as well as continuous systems. The salt release from polymer into water depends on such parameters as salt content, temperature, water flow rate, and salt particle size.