Studies in piperazine containing poly(sulphone-amide)s for use in water desalination

摘要

Poly(sulphone-amide) polymers were prepared from reactions of 4,4′-diaminodiphenylsulphone (DDS) and piperazine with isophthaloyl chloride (ICl) or terephthaloyl chloride (TCI) in N-methylpyrollidone (NMP) by low temperature polycondensation. Properties such as inherent viscosity, percent moisture regain, percent solubility in different solvents, chlorine absorbance and thermal analysis were studied. Membranes were cast from solutions of these polymers in N, N′-dimethylacetamide (DMAC) containing dissolved lithium chloride/calcium chloride/lithium nitrate as additive salts. The reverse osmosis (RO) membrane performances were evaluated using aqueous sodium chloride feeds with and without chlorine addition at 70 kg · cm~(-2) operating pressure.