The optimum reaction time and temperature for the synthesis of polyethylene oxide PEO from ethylene oxide EO monomer depend on the specific catalyst and reaction conditions being used. Generally, the polymerization of EO is carried out using anionic or cationic catalysts, with the most common being potassium alkoxides or boron trifluoride etherate, respectively.For anionic polymerization using potassium alkoxides, the typical reaction temperature ranges from 100 to 150C. The reaction time can vary from a few hours to several days, depending on the desired molecular weight and the concentration of the catalyst. Higher temperatures and longer reaction times can lead to higher molecular weights.For cationic polymerization using boron trifluoride etherate, the reaction temperature is usually lower, ranging from 0 to 50C. The reaction time can vary from a few minutes to several hours, depending on the desired molecular weight and the concentration of the catalyst. Lower temperatures and shorter reaction times can lead to higher molecular weights.Altering the reaction time and temperature can significantly affect the molecular weight and properties of the resulting PEO polymer. In general, increasing the reaction time or temperature leads to higher molecular weights, while decreasing them results in lower molecular weights. The molecular weight of the polymer influences its properties, such as viscosity, solubility, mechanical strength, and thermal stability.Higher molecular weight PEO polymers tend to have higher viscosities, better mechanical strength, and higher thermal stability. However, they may also have lower solubility in some solvents. Lower molecular weight PEO polymers, on the other hand, have lower viscosities, weaker mechanical strength, and lower thermal stability, but they may have better solubility in some solvents.It is essential to optimize the reaction time and temperature to achieve the desired molecular weight and properties for a specific application of the PEO polymer. This can be done through careful experimentation and by considering the specific requirements of the intended use of the polymer.