The optimal reaction conditions for synthesizing polyethylene terephthalate PET from terephthalic acid and ethylene glycol involve a two-step process: esterification and polycondensation.1. Esterification: In this step, terephthalic acid reacts with ethylene glycol to form bis 2-hydroxyethyl terephthalate BHET . The optimal reaction conditions for this step are: - Temperature: 220-260C - Pressure: Atmospheric pressure - Catalyst: Typically, an acid catalyst like zinc acetate, antimony trioxide, or titanium IV butoxide is used.2. Polycondensation: In this step, BHET undergoes polymerization to form PET. The optimal reaction conditions for this step are: - Temperature: 270-290C - Pressure: Reduced pressure 0.1-2 mmHg to facilitate the removal of ethylene glycol formed during the reaction - Catalyst: Antimony trioxide Sb2O3 is the most commonly used catalyst, but other catalysts like germanium dioxide GeO2 or titanium IV butoxide can also be used.These conditions should result in a high yield and quality of polyethylene terephthalate. However, it is important to note that the specific conditions may vary depending on the reactor setup and the desired properties of the final product.