Investigation of optimal parameters for producing an ion‑exchange material based on polyethylene terephthalate modified with polyethyleneimine

This study investigates the principles of producing an ion-exchange material based on polyethylene terephthalate chemically modified with polyethyleneimine.The effects of temperature, polyethyleneimine concentration, and modification duration on the static exchange capacity of the resulting ion exchanger were examined.The modification of polyethylene terephthalate was carried out at temperatures of 50, 70, 80, 90, and 100°C.It was found that increasing the temperature leads to an increase in the material's static exchange capacity, ranging from 1.2 to 4.6 meq/g.The influence of polyethyleneimine concentration was investigated within the 20-100 % range; a maximum exchange capacity of 4.6 meq/g was achieved at a concentration of 80 %.The effect of modification duration was studied over an interval of 2 to 18 hours.It was shown that extending the reaction time up to 12 hours increases the exchange capacity, whereas further increases in time result in virtually no change to this parameter.Based on the collective results, the optimal process parameters were determined to be a temperature of 100°C, a polyethyleneimine concentration of 80 %, and a modification duration of 12 hours.The findings demonstrate the potential of chemically modifying polyethylene terephthalate with polyethyleneimine for the production of polymeric ionexchange materials.