Fully optimized calculation and frequency analysis for polyoxymethylene dimethyl ethers (PODE) were carried out using a density function theory (DFT) method at the B3LYP/6-31＋G(d,p) level. The structural and thermodynamic parameters of PODE were obtained. In addition, the standard enthalpies of PODE were calculated by designing the isodesmic reactions. Accordingly, the equilibrium constants and equilibrium conversions for the synthesis reactions of PODE were derived, according to which the thermodynamic feasibility for the synthesis of PODE with different feed stocks was assessed.

Key words: polyoxymethylene dimethyl ether (PODE), thermodynamic parameter, thermodynamic equilibrium conversion, density function theory (DFT), isodesmic reaction