SU326196A1 - METHOD OF OBTAINING POLYPHENYLENE ETHERS - Google Patents

Description

This invention relates to the synthesis of polymers on the axis of mixed phenols. Polyphenylene oxide (poly-2,6-dimethyl-1,4phenylene oxide), related to the niphenylo esters, is a thermoplastic with high mechanical, electrical and thermal characteristics. Especially important is its heat resistance. Nylonphenylene oxide products in a wide range of temperature (–200–190 ° C) do not change their dielectric properties and shape, are resistant to aggressive media, steam, hard radiation and fungi, which allows the use of the polymer in electricity and radii .nike, in the chemical industry and medicine. A known method for the synthesis of polyphenylene oxide by oxidative polycondensation of substituted monocyclic phenols, for example 2,6-dimethylphenol, consists in oxidizing the corresponding phenol with oxygen in the presence of a catalyst — a complex of basic copper salt and nervous, secondary, or secondary tertiary amine. In order to increase the molecular weight of the final products and accelerate the polycondensation process, it is proposed to use as a catalyst a complex of basic salt of divalent copper, amine and ketone, for example acetone. The increase in the molecular weight of the polyphenylamine ethers depends on the amount of ketone introduced, which makes it possible to regulate the molecular weight of the niphenylene ester and, therefore, to obtain various grades of these polymers, from Linga to film-forming. Accelerating the reaction of oxidative non-condensation with the introduction of ketone as a cocatalyst will allow to intensify the process of obtaining polyfeiylene esters. In catalysts containing the basic salt of divalent copper, amine and ketone, you can use the salt of divalent copper with the appropriate stoichiometric additives of alkali or metallic copper. In the latter case, the basic salt is formed during the oxidative condensation reaction process using the reaction water. You can use salts of monovalent copper, which, being oxidized in the reaction medium, form basic salts, also with the use of reaction water. The only requirement that salts of monovalent copper must satisfy is the possibility of its transition to a bivalent state and the possibility of forming complexes with amines soluble in the reaction medium.

The complex of basic salt of divalent copper with amines, which is a component of the proposed catalytic system, can also be obtained by treating the salt of divalent copper with divalent copper hydroxide, alkali metal phenols or ion-exchange resin, adding the amount of acid to copper hydroxide, etc. These reactions Preferably predominantly in the amine medium.

For the preparation of the catalyst, chloride and chlorine, bromine and bromine copper, oxide sulfate and copper oxide, oxide copper oxide and oxide copper, formate, copper acetate and benzoate are most commonly used.

Among the amines used are aliphatic and cyclic primary, secondary and tertiary mono- and nolyamines, for example ethyl, DIETHYL, triethylamine, pyridine, niperidine, hexamethylenediamine, N, N, N, N-TeTramethylethylenediamine, quinoline, phenanthroline. Examples of ketones are compounds

R. general formula ;; where R and Ri - al1 /

kil and aryl. Usually use 1-500 weight. including ketone on 1 weight, including salts of copper.

The solvents used are polar and non-polar solvents and their mixtures, in particular amines, amides, nitriles, alcohols, aromatic hydrocarbons, chlorinated hydrocarbons, mixtures of aromatic and chlorinated hydrocarbons with amines and alcohols, etc.

Example. Catalytic system: basic salt of copper - amine - ketone.

The concentration of reagents (in mol / l):

Copper salt0.121 const

2,6-Dimethylphenol 0.4 Acetone0-3.63

5 g of 2,6-dimethylphenol and 1.15 g of freshly recrystallized copper monochloride, 70-100 ml of pyridine and O-30 ml of acetone are loaded into the ampoule equipped with a jacket, provided that the total amount of liquid is 100 ml. The reaction mixture was shaken for 5 minutes at a temperature of 30 ° C and an oxygen pressure of 1 MPa.

The reaction rate is determined by the absorption of oxygen.

The polymer is planted with acidic methanol, washed with methanol on a filter, then treated with acetone in a Soxhlet apparatus and in vacuum at 50 ° C for 4 hours.

The viscosity of polymer solutions is determined in benzene at 25 ° C.

The results of the experiments are tabulated.

Subject invention

Spoooob. The production of polyphenylene ethers by oxidative polycondensation of substituted phenols, for example 2,6-dimethylphenol, under the action of oxygen in the presence of medoamine catalysts, characterized in that, in order to increase the rate of the polycondensation process and the molecular weight of the final products, a catalyst consisting of from basic salt of divalent copper, amipa and ketone, for example acetone.