The synthesis of polyethylene oxide PEO with a specific molecular weight, such as 50,000 g/mol, can be achieved through the ring-opening polymerization of ethylene oxide EO monomer. The reaction is typically catalyzed by a base or an acidic catalyst. The optimal reaction temperature and pressure for this process depend on the specific catalyst used and the desired reaction rate.For example, when using a base catalyst like potassium hydroxide KOH , the optimal reaction temperature is usually in the range of 50-80C, and the pressure should be kept close to atmospheric pressure 1 atm to maintain a reasonable reaction rate. On the other hand, when using an acidic catalyst like boron trifluoride etherate BF3OEt2 , the reaction temperature can be higher, around 100-120C, and the pressure can be slightly elevated, up to 2-3 atm, to achieve the desired molecular weight.It is essential to note that the reaction conditions should be adjusted based on the specific catalyst and reaction system used. Additionally, controlling the reaction temperature, pressure, and catalyst concentration is crucial for achieving the desired molecular weight of the PEO product.