the influence of catalysts, one-step process requires more active catalysts than the prepolymerization method, which usually uses a composite catalytic system of organotin and tertiary amines. organotin catalysts are generally used in the past, but the compound is easy to cause thermal oxygen aging, is the ether bond in the case of heating to accelerate the cleavage and degradation of polymer molecules, so most of the current use of stannous compounds, such as stannous octanoate, etc.. and the compression load value of the resulting products is also larger, as follows.
