RU2248377C1 - Method for production of powder aromatic copolymers - Google Patents

Abstract

FIELD: production of powder aromatic copolymers useful in plastic article, as well as lacquer and film material manufacturing.

SUBSTANCE: aromatic diamine or bisphenol solution is blended in mixture of tetrahydrofuran and water, containing inorganic salt or mixture of inorganic salt and alkali, with melt of therephthalic acid dichloroanhydride, wherein for 2-5 min before blending isophthalic acid dichloroanhydride is added. Blending is carried out at rate of 808.5 m/s, at 20⁰C for 2-3 min. Copolymer is deposited with water in ratio water/tetrahydrofuran of (2.0-2.29):1.

EFFECT: copolymers of high molecular weight.

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Description

The present invention relates to the field of obtaining copolymers of dichlorohydrides of phthalic acids with bis-phenols or aromatic diamines, intended for the production of plastic products, as well as varnishes and film materials with high heat resistance and enhanced physical and mechanical characteristics.

A known method for producing such copolymers by mixing isophthalic acid dichloride dissolved in a water-immiscible solvent, for example methylene chloride, with an aqueous solution of aromatic diamine in the presence of mineral acid and alkaline carboxylic acid salt - AcONa [1]. The disadvantage of this method is the presence of complex salt and the associated problem of its disposal, as well as the difficulty in removing the solvent which is not miscible with water and salts from the polymer, which negatively affects the properties of the products during polymer processing.

In another known method, phthalic acid dichlorides are dissolved in tetrahydrofuran, which is mixed with water, an aqueous solution of diamine dichlorohydrates and also in the presence of complex salts is used in the synthesis [2]. The disadvantages of this method are the problem of the disposal of complex salts, the use of dichlorohydrates instead of pure diamines, as well as the low molecular weight of the resulting copolymers due to the hydrolysis of dichlorohydrides when dissolved in THF, which always has a low humidity.

Closest to the claimed method is to obtain copolymers from dichlorohydrides of phthalic acids and bis-phenols by mixing a solution of bis-phenol in a mixture of tetrahydrofuran-water containing an inorganic salt and alkali with a solution of phthalic dichlorides in tetrahydrofuran at a temperature below 20 ° C for 2 -3 min followed by precipitation with water [3]. The disadvantage of this method is the insufficiently high molecular weight of the resulting copolymers due to the hydrolysis of dichlorohydrides, as well as the contamination of the polymer with the ingredients of the reaction mixture due to its lumpiness due to insufficient mixing during synthesis and precipitation of the polymer.

The aim of the proposed method for producing copolymers is to obtain them in the form of a powder with high molecular weight.

The essence of the invention is as follows: The process is carried out in a reactor with a high-speed stirrer having a peripheral speed of 8.0-8.5 m / s, before loading phthalic acid dichlorides, they are melted, and terephthalic acid dichloride is first melted and 2-5 minutes before draining isophthalic acid dichloride is introduced into the reactor into the melt. The melt and the solution of diamines or bis-phenols are mixed for 2-3 minutes, after which water is supplied to the reactor in an amount of 2.0-2.29 volumes per volume of tetrahydrofuran.

Example 1. In a reactor with a high-speed open-type turbine stirrer having a diameter of 0.03 mm, a peripheral speed of 8.5 m / s, pour 0.32 L of water, 0.32 L of tetrahydrofuran, add 12.88 g of m-phenylenediamine, 25.10 g of sodium carbonate are dissolved in 10 minutes and cooled to + 15 ° C. 9.66 g of terephthalic acid dichloride is poured into the melter, melted, 2.5 minutes before the melt is drained, 14.53 g of isophthalic acid dichloride is poured into it, the contents of the melter are poured into the reactor, mixing is carried out for 2 minutes, after which 0, 65 liters of water for planting. The ratio of the volume of water to the volume of tetrahydrofuran is 2.03.

The resulting copolymer is in powder form

η _beats = 1.52, MM = 37000

The specific viscosity was determined according to GOST 1103.

The peripheral speed - W okr of the mixer is calculated by the formula

W _ocp = π _m ND,

where N is the frequency of rotation of the mixer, s ^-1 ;

D is the diameter of the mixer [4].

Example 2. In a reactor with a fast open-type turbine stirrer having a diameter of 0.2 m and a peripheral speed of 8 m / s, pour 48 L of water, 48 L of tetrahydrofuran, pour 560 g of n-phenylenediamine, 1654 g of m-phenylenediamine, 4336 g sodium carbonate, dissolved in 20 minutes and then cooled to + 10 ° C. 2090 g of terephthalic acid dichloride is poured into the melter, melted, and 568 minutes before the melt is discharged, 2068 g of isophthalic acid dichloride is charged into it, the contents of the melter are poured into the reactor, stirring is carried out for 3 minutes, after which 110 l of water are precipitated into the reactor. The ratio of the volume of water to the volume of tetrahydrofuran is 2.25.

The resulting copolymer has the form of a powder and η _beats. = 1.28, MM = 29000

Example 3. In a reactor with a fast turbine mixer of an open type, having a diameter of 0.06 m and a peripheral speed of 8.2 m / s, pour 2.3 l of water, 2.3 l of tetrahydrofuran, 192 g of diphenylolpropane, 326 g of sodium chloride are poured , 75 g of sodium hydroxide, dissolved in 15 minutes and cooled to 20 ° C. 86.4 g of terephthalic acid dichloride is poured into the melter, melted, 3 minutes before the melt is drained 86.4 g of isophthalic acid dichloride is poured into it, the contents of the melter are poured into the reactor, stirring is carried out for 2.5 minutes, after which it is poured into the reactor 5 l of water for planting. The ratio of the volume of water to the volume of tetrahydrofuran is 2.17. The resulting copolymer has the form of a powder and η _beats. = 1.02, MM = 22500

Example 4. In a reactor with a fast turbine mixer of an open type, having a diameter of 0.13 m and a speed of 8.3 m / s, pour 12 L of water, 12 L of tetrahydrofuran, pour 1000 g of phenolphthalein, 1875 g of sodium chloride, dissolve for 20 min and cooled to + 12 ° C. 638 g of terephthalic acid dichloride is poured into the melter, melted, and 638 g of isophthalic acid dichloride is charged into the reactor 3 minutes before the melt is drained, the contents of the melter are poured into a reactor into which 690 g of a 40% alkali solution has previously been poured. The melt is mixed with a solution of bis-phenol for 3 minutes, after which 25 liters of water are deposited into the reactor for precipitation. The ratio of the volume of water to the volume of tetrahydrofuran is 2.08. The resulting polymer has the form of a powder and η _beats. = 0.93, MM = 20,000

Thus, the proposed method makes it possible to obtain copolymers in the form of a powder and with a molecular weight that allows them to be used for the production of plastic products, varnishes and film materials.

Literature

1. US Patent No. 3624033 from 07/09/1969, publ. 11/30/1971.

2. Japanese Patent No. 18874 filed April 11, 1967, publ. 06/27/1970.

3. USSR copyright certificate No. 493119, publ. 10/26/1977.

4. F. Holland, D. Chopman “Chemical reactors and mixers for hydrophase processes”. M .: Chemistry, 1974

Claims (1)

A method of producing powders of aromatic copolymers, which consists in mixing a solution of aromatic diamine or bis-phenol in a mixture of tetrahydrofuran-water containing an inorganic salt or inorganic salt and alkali with a melt of terephthalic acid dichloride, to which is added 2-5 minutes before mixing isophthalic acid dichloride at a speed of 8-8.5 m / s and a temperature of no higher than 20 ° C for 2-3 minutes, then the copolymer is precipitated with water taken in relation to tetrahydrofuran in the ratio (2.0-2.29): 1 .