PREPARATION OF SOME LARGE CYCLIC OXYETHYLENE SUCCINATE ETHER-ESTERS

Cyclic oligomers of tetraethyleneglycol succinate [O(CH2CH2O)(4) . CO . CH2CH2 . CO](x), pentaethyleneglycol succinate [O(CH2CH2O)(5) . CO . CH2CH2 . CO](x) and hexaethyleneglycol succinate [O(CH2CH2O)(6) . CO . CH2CH2 . CO](x) were prepared by dilute solution ringchain transeste rification reactions. The cyclic products were characterized by GPC, F AB mass spectrometry and NMR spectroscopy. The molar concentrations of the cyclics were determined using GPC and are compared in this paper. The cyclic ether-ester oligomers were fractionated by preparative GPC to give a series of narrow molar mass fractions with dispersities (<( M)over bar(w)>/<(M)over bar(n)>) of c 1.05. The cyclic tetraethylenegl ycol succinate monomer was crystallized and its structure determined b y X-ray crystallography.