Copper - mixed n-butylamine/dibutylamine complex was used as the catalyst for 2,6-dimethylphenol polymerization. The effects of several variables such as copper salts, additives, reaction temperature and pressure, and amine/copper ratio on the catalyst performance were studied. The catalyst activity was found to be highly dependent on the specific combination of copper salts and amines, and copper iodide - amine complex showed an unusual long induction period. Polymer molecular weight was sensitive to the addition of methanol and surfactant, reaction temperature and amine/copper ratio but insensitive to the pressure. Initial polymerization rate was strongly affected by reaction pressure.