TFPX synthesizing method

Abstract

The invention relates to a synthesis method for TFPX (alpha,alpha,alpha', alpha'tetrafluoro-p-xylene), including the following steps: (a)supplying a sulpholane solution containing TCPX (alpha,alpha,alpha', alpha'tetrachloro-p-xylene), (b) making a mixture of the sulpholane solution, a fluoride salt and a PTC, in which, PTC is quatermary phosphate, and (c) heating the mixture to get a product.

Description

technical field [0001] The invention relates to a synthesis method, especially a preparation method suitable for preparing tetrafluoro-p-xylene (TFPX). Background technique [0002] Since parylene polymer has many processing advantages, such as the coating environment is room temperature, no residual stress occurs after coating and the thickness of the deposited film can be precisely controlled, and the parylene film is uniform, acid-resistant and resistant. Alkali, colorless, high transparency, low dielectric...etc. Therefore, it is widely used in the electrical isolation of printed circuit boards, the moisture protection of sensors or medical instruments, and the corrosion protection of metal coatings...etc. Currently, fluorine-containing polyparaxylylene (fluoroparylene polymer) has a low dielectric constant and a high melting point, and will be used as a dielectric film in the electronics and paint industries. [0003] Fluoro parylene polymer has the structure of the f...

AI Technical Summary

Problems solved by technology

[0010] However, the current methods for synthesizing TFPX are very expensive, time-consuming, and cannot be used for scale-up processes

For example, after mixing α, α, α', α'-tetrachloro-p-xylene (α, α, α', α'tetrachloro-p-xylene, TCPX) and KF in an appropriate proportion, in a closed Or carry out the reaction in an open reaction vessel. The reaction lasts for 12 hours at a temperature of about 260-280°C. Although TFPX products can be obtained, since no other solvents are added, it is a similar solid-phase reaction. If the stirring is not good, serious gums are likely to occur The problem of agglomeration not only affects the yield, but also is not suitable for the expansion process

Some organic compounds containing carbonyl functional groups (carbonyl group), such as terephthalaldehyde (terephthaaldehyde), and fluorinating agent SF 4 、MoF 6 , DAST or HF / Py in appropriate solvent and temperature for fluorination reaction, although higher yields of TFPX can be obtained, but the price of these fluorinating agents is expensive, the reaction equipment and operating conditions are relatively harsh, and waste gas and waste liquid Difficult to handle

It can be seen that these methods not only greatly increase the development cost of TFPX, but also are not conducive to the expansion of production.

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