Technology for fluorinating unstable end group of perfluoropolyether

Abstract

The invention relates to the technical field of fluorine chemical, and concretely relates to a technology for fluorinating the unstable end group of perfluoropolyether. The technology comprises the following steps: 1, vacuumizing a bubble tower fluorination reactor, adding an HFPO oligomer acid fluoride and / or perfluoropolyether carboxylic acid into the reactor from the upper end of the bubble tower fluorination reactor, and heating the bubble tower fluorination reactor to 130-170 DEG C; 2, adjusting the pressure in the bubble tower fluorination reactor; 3, introducing a fluorinating agent gas, carrying out a reaction for 45-90 min, and heating the reactor to a preset reaction temperature; and 4, carrying out a reaction for 4-48 h, stopping the introduction of the raw material when the reaction is finished, carrying out nitrogen purging, cooling the obtained material to 40 DEG C or below, and discharging the cooled material. The end group of the HFPO oligomer acid fluoride and / or perfluoropolyether carboxylic acid is treated with fluorine gas by using the bubble tower fluorination reactor, so the utilization efficiency of the fluorine gas is greatly improved, and an ideal effect isachieved.

Description

technical field [0001] The invention relates to the technical field of fluorine chemical industry, in particular to a fluorination process for unstable terminal groups of perfluoropolyether. Background technique [0002] Perfluoropolyether has excellent high and low temperature stability, low surface tension, chemical inertness, non-flammability, low volatility, good lubricity, water and solvent resistance, excellent radiation stability, compatibility with metal plastic elastomers, With high dielectric properties, non-toxicity and excellent viscosity-temperature characteristics, it is widely used as high-vacuum pump oil, lubricant, insulating fluid, heat transfer fluid and cooling fluid in the fields of electronics, military industry, nuclear energy, and high-end equipment. [0003] The currently marketed perfluoropolyethers mainly include K-type prepared by ring-opening polymerization of hexafluoropropylene oxide, Y-type prepared by oxygen oxidation of hexafluoropropylene, ...

AI Technical Summary

Problems solved by technology

[0004] At present, there are two main methods for fluorinating the unstable terminal groups of perfluoropolyether, one is to use AlF 3 , SbF 5 High-temperature fluorination of solid fluorinating agents such as solid fluorinating agents, but the price of fluorinating agents used in this method is relatively high, and the separation of products is difficult, and the metal ions in it are difficult to remove completely, which will greatly affect product quality; The end group fluorination of fluoropolyether, the product obtained by this method is pure, and the post-treatment is simple, but due to the low solubility of fluorine gas in the reactant, it is difficult to fully react with the active end group of perfluoropolyether, and the currently existing For example, fluorination reaction equipment such as reactors have the disadvantages of insufficient gas-liquid contact and low utilization rate of fluorinating agent. A large excess of fluorine gas is required, and the general dosage needs to be more than ten times the theoretical value, and a longer reaction time is required. , the overall reaction efficiency is low, the reaction cost is high, and the tail gas treatment capacity is increased, which is not conducive to environmental protection

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