DE1084712B - Process for the production of higher molecular weight epoxy fatty acid esters - Google Patents

Description

Process for the production of higher molecular weight epoxy fatty acid esters It has been found that higher molecular weight esters containing epoxy groups are obtained can, if you fatty acid esters, their acid and / or alcohol content is unsaturated is, in the presence of di- or polycarboxylic acids and of acidic, with the carboxylic acids mixed anhydride-forming catalysts (activators) with hydrogen peroxide treated. The total amount of di- or polycarboxylic acids and acidic catalyst should usually not more than 0.5 mol per double bond of the starting material. The reaction temperature to be used is from 0 to 1000.degree. C., preferably from 40 to 60.degree.

Suitable esters of unsaturated fatty acids are: the naturally occurring glycerides, the fatty acid content of which is mono- or polyunsaturated can be, such as B. semi-drying oils, especially soybean oil, cottonseed oil and linseed oil. Olive oils, nipple oil, sperm oil and other marine animal oils are also suitable.

Further come z. B. Esters of the following alcohols as starting materials for the claimed process into consideration: ethyl, isopropyl, n-butyl, sec-butyl, tert. Butyl, tert. Amyl, n-octyl, 2-ethylhexyl, dodecyl, octadecyl, octadecenyl, Cyclohexyl, methylcyclohexyl, naphthenyl, benzyl alcohol and the like, polyhydric Alcohols such as ethylene glycol, 1,2-propylene glycol, 2-ethylenehexanediol-1,3, butanediol-1,4, Dodecanediol-1, i2 diethylene glycol, glycerine, pentaerythritol and others. Also esters from unsaturated Carboxylic acids and alcohol mixtures can be used as starting materials as well Mixed esters of polyhydric alcohols and various unsaturated fatty acids, such as B. the mixed ester of ethylene glycol with oleic acid and linseed oil fatty acid.

Furthermore, esters of unsaturated higher molecular weight can be used as starting materials Use alcohols such as B. the esters of naturally occurring by reduction Vegetable or animal unsaturated fatty acids with preservation of the double bond obtained alcohols, or esters of unsaturated alcohols, which by splitting natural Wax esters are obtained, such as. B. Esters of unsaturated fatty alcohols C14bis C18, especially of oleyl alcohol and other mono- or polyunsaturated Alcohols with any low or high molecular weight carboxylic acids. In the end - Esters in which both the acid and the alcohol content can also be used has a mono- or polyunsaturated hydrocarbon radical.

The starting materials mentioned are according to the invention with a di- or epoxidation mixture containing polycarboxylic acids. Di- or polycarboxylic acids, which are suitable for this purpose are, for example, succinic acid, adipic acid, Maleic acid or its halogen substitution products, fumaric acid, citric acid, Acetonedicarboxylic acid, sebacic acid, phthalic acids, benzene polycarboxylic acids or their Halogenated tion products, polyacrylic acids or others containing several carboxyl groups Polycondensation products, base exchange resins containing carboxyl groups, etc. It is also possible to use mixtures of di- or polycarboxylic acids. Further Polycarboxylic acids come into consideration, which are saturated by oxidative cleavage or unsaturated fatty acids or their esters, or mixtures thereof.

As catalysts (activators) that lead to the formation of mixed anhydrides are capable of the aforementioned di- or polycarboxylic acids, inorganic ones come or organic acids or acid halides in question, such as mineral acids, such as phosphoric acid, nitric acid, sulfuric acid, perchloric acid, boron trifluoride or Boron trifluoride water adducts, also acidic phosphoric acid esters, p-toluenesulfonic acid High molecular weight resins containing sulfonic acid groups, inter alia. Part of these activators is known under the name "Lewis acids". They have the ability to produce peracid to facilitate or speed up by using the di- or polycarboxylic acids come together intermediately to form high-energy mixed anhydrides.

The epoxidation proceeds in such a way that the di- or polycarboxylic acids in the presence of the unsaturated ester to be epoxidized initially by the influence the activators are able to work with the hydrogen peroxide with the formation of corresponding Peracids, which facilitate the transfer of active oxygen to the double bond of the cause unsaturated esters to react.

The proportions in which the reactants use find are based primarily on the number of those in the source material Double bonds which should be converted into epoxy groups.

The concentration of active oxygen, i.e. H. the content of hydrogen peroxide, in the reaction mixture should be between 1.1 and 2 moles per mole of double bond.

The maximum amount of di- or polycarboxylic acids and activator required should in general not exceed 0.5 mol per Mp double bond.

Only in the case of using a carboxyl group-containing one Base exchange resin (polycarboxylic acid) as an oxygen carrier, it is recommended to use slightly larger amounts. It is appropriate to use the proportion of di- or polycarboxylic acids for reasons of economy and to suppress side reactions so to keep as low as possible, when using too high proportions of di- or polycarboxylic acids it can decompose as a result of an increase in the reaction rate and temperature of the epoxy groups to form dioxy and acyloxy derivatives, which the Reduce the value of the epoxy compounds.

The procedure is carried out in such a way that first the starting material to be epoxidized with the di- or polycarboxylic acid and the acidic one Activator mixed in the reaction vessel and a temperature of preferably 40 is brought to 6Q ° C. Then stir vigorously for a longer period of time Period, the calculated amount of at least 30 years, preferably 50 to 60 ° / Oigen aqueous hydrogen peroxide solution added, the reaction temperature if necessary, is kept at the specified value by cooling. After finished In many cases, it is advantageous to add hydrogen peroxide to the temperature of the Reaction mixture by interrupting the cooling or, if necessary, by supplying heat increase to bring the reaction to completion.

The inventive method has over other known Epoxidation process has a number of benefits. By extending the addition of hydrogen peroxide The oxidizing agent is always in such a dilution over a period of several hours suggests that the explosive limit of the peracids formed as intermediates is not reached will. In addition, the peracids formed from the di- or polycarboxylic acids tend to contribute nowhere near as capable of forming explosive mixtures as in the known epoxidation processes Performic acid or peracetic acid formed. Compared to known processes, in which the total amount of hydrogen peroxide required is in the reaction mixture from the outset is present, it is also achieved that the epoxidation process with respect to control the exothermic reaction process can be controlled more easily. As a result of the delayed course of the reaction, there is also the risk of the formation of undesired dioxy- or acyloxy compounds reduced by splitting the epoxy ring. In the event of the use of synthetic resins containing carboxyl groups results in the further advantage that even in amounts above 0.5 mole per mole of double bond no splitting of the Cause formed epoxy groups. According to the method according to the invention can the reaction product is much easier to work up after the reaction has ended than when using formic acid or acetic acid, since the according to the invention as Oxygen carriers used di- or polycarboxylic acids after cooling of the Reaction mixture present in solid form and from the epoxy compounds formed separated off by filtration and used again without further regeneration measures can be.

The higher molecular weight epoxy esters obtainable in the specified route have a wide range of technical interests. You are e.g. B. because of their good tolerance and Migration resistance as plasticizers and stabilizers for polyvinyl chloride and its copolymers are important auxiliaries for plastics processing. Farther they can be used as lubricants, lubricating oil additives or textile oils.

The process according to the invention is illustrated below with the aid of a few examples explained in more detail: Example 1 In a VA stirred vessel equipped with heating and cooling coils 750 parts by weight of a soybean oil (SZ = 0.2, VZ = 188, 0HZ = 2, JZ = 122), 100 parts by weight of techn. Succinic acid and 10 parts by weight of 70 to 80 ° 10% sulfuric acid brought in. The contents of the kettle are then heated to a temperature of 40 to 45 ° C. In the course of 3 to 4 hours, with stirring, 300 parts by weight of a 50 weight percent Hydrogen peroxide solution added, the temperature by cooling to 40 to 45 "C is held.

After the addition has ended, the cooling is left by throttling the temperature of the boiler contents rise to 50 to 60 "C. At this temperature the reaction product is stirred for 10 to 12 hours - and then with Washed neutral in water. To remove small amounts of still remaining acidic It is refined with diluted lye and washed neutral.

Obtained after heating to 70 to 90 "C under reduced pressure a dry soybean oil epoxy with an epoxy oxygen content of 5.3 01o (JZ = 30.2, SZ = 0).

Example 2 If the method of operation of example 1 is modified to the effect that that with otherwise constant conditions instead of succinic acid, 50 parts by weight Adipic acid and 50 parts by weight of concentrated phosphoric acid are obtained after 15 hours a soybean oil epoxy with an epoxy oxygen content of 4.3 (SZ = 0, JZ = 50.2).

Example 3 A cation exchange synthetic resin containing carboxyl groups (»Levatit CNO«) is swollen with dilute phosphoric acid and after 2 to 3 hours Let stand pressed. 100 parts by weight of the resin prepared in this way are with Slurried 50 parts by weight of concentrated phosphoric acid, stirred for a few hours and then freed from liquid components by pressing again. to 750 parts by weight of a well deacidified soy oil are added to this resin (SZ = 0.2, VZ = 188.5, OHZ = 2.9, JZ = 129) and adds at a temperature of about 40 to 45 "C 300 parts by weight of a 60 percent by volume hydrogen peroxide solution with stirring to. The feed ended after 3 hours. Then the temperature is increased to about 50 to 60 ° C. and stir the mixture for a further 10 to 12 hours.

Then the solid fractions are filtered off from the raw epoxide. This will refined, washed and dried by known processes. A product is obtained with an epoxy oxygen content of 3.24ovo (SZ = 0, JZ = 67.7).

Example 4 1000 parts by weight of a cottonseed oil fatty acid methylcyclohexyl ester (made from the liquid components of a cottonseed oil fatty acid and methylcyclohexanol; VZ = 147, JZ = 97, AN = 0.17, OHZ = 1.4) with 131.5 parts by weight of succinic acid and 13.2 parts by weight of 70 to 80 ° 10iger sulfuric acid and mixed to a temperature brought from 40 to 45 "C.

The mixture is then stirred in over a period of 4 hours more careful Maintaining the temperature of 45 "C. 400 parts by weight of a 60 percent by volume hydrogen peroxide solution a. The temperature is then increased to 50 to 60 ° C. and the batch is stirred 12 to 14 hours after. After cooling down, the contents of the kettle are drawn in which the succinic acid has largely precipitated in crystalline form, through a filter device away.

About 75 to 800 / o of the succinic acid used is recovered, which can be used again in a new approach. The reaction product will deacidified in a refining tank, washed and then under reduced pressure Pressure released from the water. The epoxy obtained in this way has an epoxy oxygen content of 4.2 01o and a JZ of 12.4.

Example 5 If you work according to the instructions in Example 1 instead of succinic acid with 100 parts by weight of citric acid, a product is obtained with an epoxy oxygen content of 3.0% (SZ = 0, JZ = 76).

Example 6 200 parts by weight of a soy fatty acid butyl ester (AN = 0, VZ = 165, 0HZ = 2, JZ = 110) are according to the information in Example 1 in the presence of 20 parts by weight of succinic acid and 12 parts by weight of 70 to 800% sulfuric acid epoxidized with 360 parts by weight of a 60 percent by volume hydrogen peroxide solution. After working up, an epoxy ester with an epoxy oxygen content is obtained of 4.10 01o and a JZ of 15.0.

Example 7 580 parts by weight of an oleyl phthalate are epoxidized with 340 parts by weight of 40 oil strength hydrogen peroxide in the presence of 16 parts by weight one pretreated with dilute acid and then washed neutral and then dried, sulfonic acid group-containing cation exchanger and 40 parts by weight Adipic acid for a total of 15 hours at 65 "C, so you get a light oil with a Epoxy oxygen content of 5.5 0 /, and an JZ of 2.8.

Example 8 Closely based on the procedure of Example 1 750 parts by weight of an oleyl ester (SZ = 0.5, VZ = 106.5, JZ = 86.3, 0HZ = 10.0) with 60 parts of adipic acid and a mixture of 350 parts by weight of a 60 percent by volume hydrogen peroxide solution and 8 parts by weight more concentrated Phosphoric acid reacted at a temperature of 50 "C. The feed of the hydrogen peroxide ends after 3 hours. The mixture is then kept under constant stirring another 10 to 12 hours at a temperature of 50 to 60 "C. After work-up an epoxy ester that is waxy in the cold is obtained (SZ = 0.7, VZ = 104.8, JZ = 5.9, epoxy oxygen content = 4.48 01o corresponding to about 900 / o of theory).

Claims (5)

PATENT CLAIMS. 1. Process for the production of higher molecular weight epoxy fatty acid esters by converting fatty acid esters whose acid and / or alcohol content is unsaturated is, with hydrogen peroxide in the presence of a carboxylic acid and an acidic catalyst, characterized in that a mixture of the ester to be epoxidized with the acidic catalyst and a di- or polycarboxylic acid 1.1 to 2 mol of hydrogen peroxide per double bond at a temperature of 0 to 1000 G, preferably 40 to 60 "C, adds, the total amount of di- or polycarboxylic acids and catalyst not is greater than 0.5 mol per double bond of the ester to be epoxidized. 2. The method according to claim 1, characterized in that the Gradual addition of hydrogen peroxide, expediently over a period of several hours, performs. 3. The method according to claim 1 and 2, characterized in that one used as dicarboxylic acid, succinic acid. 4. The method according to claim 1 and 2, characterized in that one as a polycarboxylic acid, a cation ion exchanger containing carboxyl groups - synthetic resin used. 5. The method according to claim 1 to 4, characterized in that one as a catalyst (activator) phosphoric acid or 70- to 8001, sulfuric acid used. Documents considered: German Auslegeschrift No. 1,024,514.