SU431162A1 - METHOD OF OBTAINING GLYCIDYL ETHERS OF CARBONIC ACIDS - Google Patents

Description

one

This invention relates to a process for the preparation of carboxylic acid glycndyl esters used in the polymer industry.

A known method for the preparation of glycidyl esters of carboxylic acids by the interaction of carboxylic acids or their anhydrides with epichlorohydriom at 50-110 ° C in the presence of catalysts (tertiary amines, tetrasubstituted ammonium bases or their salts in an amount of 0.1-1% by weight of acid) followed by alkaline dehydrochlorination of the resulting chlorohydrin esters of carboxylic acids and the selection of the target products by known methods.

In a known way, from dibasic carboxylic acids in the presence of tetrasubstituted ammonium salts with a yield of 80-92%, resins containing 84.5-96.4% of epoxy oxygen and 1% chlorine are obtained.

However, the impossibility of completely removing the catalysts from the target products leads to a decrease in the viability of the compositions of glycidyl ethers with hardeners, which makes it difficult to process them, especially with the simultaneous processing of large quantities.

In order to increase the purity of the target product and simplify the process, it is proposed to use an alkali metal halide as a catalyst, mainly

the amount of 0.01-0.4 mol per 1 equivalent of acid or anhydride, and the process is conducted in the presence of water, preferably in an amount of 0.2-10.0 mol per 1 equivalent of acid

or anhydride.

Depending on the nature of the starting carboxyl-containing compound, epichlorohydrin is taken in an amount of 3-15 mol per 1 equivalent of acid or anhydride (in the known

method 3-10 mol, respectively).

The proposed method is applicable for the preparation of complex glycidyl esters of saturated and unsaturated mono-, di- and polycarboxylic aliphatic, cycloaliphatic and aromatic acids. It is possible to use both the acids themselves and their anhydrides, and mixtures thereof.

The catalysts used are easily removed from the reaction mixture and, being neutral, do not reduce the quality of the cured compositions based on glycidyl esters of carboxylic acids.

The resulting target esters have low viscosity and are storage stable.

Example 1. In a flask with a thermometer, a stirrer and a reflux condenser, 18.4 g (0.1 mol) of methyltetrahydrophthalic acid, 184 g (2.0 mol) of epichlorohydrin, 0.3 g (0.004 mol) of potassium chloride, 2 g are charged.

(0.11 mol) of water and heated for 2 hours with vigorous stirring and a temperature of 90 ° C. The fatty reaction is determined by the absence of acid in the reaction mixture. After cooling to 40 ° C at 35-40 ° C and vigorous stirring, 10.0 g (0.25 mol) of caustic soda in the form of flakes are added in 1 hour, stirred for 2 hours at 35-40 ° C, the precipitate is filtered off, and the distillation the epichlorohydri "under vacuum, the residue is dissolved in 100 ml of benzene, washed with 3X20 ml of water, the benzene is distilled off under vacuum, and the residue is dried under vacuum

(750 mm) and get 23D g (78%) of a slightly colored resin with an epoxy number of 25.0 (86% of theory) and a total chlorine content of 1.3%.

In examples 2-9, the experiment was carried out under the same conditions as in example 1, using 0.1 mol of the corresponding carboxylic acid and 0.044 mol of various alkali metal halides. The results are shown in the table.

 In parentheses are the percentage of epoxy groups from the theory. It is 0.2 mol of acid. T. Kip. 98-UOS / BZ mm.

Example 10. Under the conditions of example 1 of 16.6 g (0.1 g-mol) of methyl tetrahydrophthalic anhydride (a mixture of two isomers - c "c-4 (3) -methyl - 1,2,3,6 - tetrahydrophthalic anhydride ), 83 g (0.9 g-mol) of epichlorohydrin, 1.67 (0.028 g-mol) of potassium chloride and 3.8 g (0.2 g-mol) of water receive 25.7 g (87%) of light yellow resin with an epoxy number of 26.5.

Example 11. Under the conditions of example 1 of 15.4 g (0.1 g-mol) of hexahydrophthalic anhydride, 46.1 g (0.5 g-mol) of epichlorohydrin, 1.67 g (0.028 g-mol) of chloride potassium and 8.3 ml (0.046 g-mol) of water receive 21.0 g (74.8%) of a slightly colored resin with an epoxy number of 25.3.

Subject invention

Claims (3)

1. A method of producing glycidyl esters of carboxylic acids by the interaction of acids or their anhydrides with epichlorohydrin at 50-110 ° C in the presence of catalysts with subsequent alkaline dehydrochlorination of the obtained chlorohydrin esters of carboxylic acids and isolation of the target products using known methods, in order to simplify the process and increase the purity of the target product, the halide is used as a catalyst alkali metal and the process is carried out in the presence of water. 2. A method according to claim 1, characterized in that the alkali metal halide is used in an amount of 0.01-0.4 mol per 1 equivalent of acid or anhydride. 3. The method according to claim 1, wherein water is used in an amount of 0.2-10.0 mol per 1 equivalent of acid or anhydride.