Preparation process of perfluoroether carboxylic acid for polymerizing special ternary fluororubber

The invention discloses a preparation process of perfluoroether carboxylic acid for polymerizing special ternary fluororubber. The preparation process includes the following steps: a polyether acyl fluoride oligomer obtained by performing photochemical-oxidationpolymerization on fluorinated alkene is used as a raw material, wherein the molecular weight is 300-1,500, then polyether carboxylic acidis obtained by hydrolysis, and finally, the perfluoroether carboxylic acid is obtained by direct fluorination withfluorine gas in a microchannel reactor. According to the preparation process of the perfluoroether carboxylic acid for polymerizing the special ternary fluororubber, other component residue in the target product can be reduced and the impurity separation flow of a conventional liquid phase fluorination process can be simplified, the degradation of the raw material is reduced, and the conversion rate of the perfluorinated product is higher. 本发明公开了一种用于聚合特种三元氟橡胶的全氟醚羧酸的制备工艺，它包括如下步骤：将以含氟烯烃进行光化氧化反应聚合得到聚醚酰氟低聚物为原料