The mechanism of the reaction of AKD (alkyl ketene dimer) and ethanol has been investigated using density functional theory (DFT) and Gaussian03 Quantum chemistry Packages. The geometries of AKD were optimized using the B3LYP /6-311G＋＋(d,p). The Mulliken charge distribution, energy and frontier molecular orbital characteristics were calculated using the same standards. The results show that C(54) of lactone ring has a higher positive charge, which can react with nucleophiles. The reaction products of AKD and ethanol were characterized by FT-IR which could verify the calculation results of Gaussian 03.

Key words: AKD, reactivity, density functional theory, sizing mechanism