Soluble polyesters with preformed ether and imide units: synthesis and properties

A diacid containing ether and imide units was prepared via reaction of trimellitic anhydride (2 mol) with 1,8-diamino-3,6-dioxaoctane (1 mol) by two different methods. A series of polyesters with preformed ether and imide units was prepared through polycondensation reactions of the diacid with different aromatic diols in the presence of benzenesulfonyl chloride. The polyesters showed good solubilty in polar aprotic solvents due to the presence of ether and methylene flexible groups. Physical properties of the polymers including thermal stability and behavior, inherent viscosity and crystallinity were studied.