DE1254624B - Process for the preparation of 3, 6-endoethyleneo-1, 2, 4,5-cyclohexane-tetracarboxylic acid esters suitable as plasticizers - Google Patents

Description

Process for the production of 3, 6-endoäthyleno-1, suitable as a plasticizer, 2, 4, 5-cyclohexanetetracarboxylic acid esters Process for the production of plasticizers suitable 3, 6-endoäthyleno-1, 2, 4, 5-cyclohexanetetracarboxylic acid esters It was found that there are suitable 3, 6-endoäthyleno-1, 2, 4, 5-cyclohexanetetracarboxylic acid esters as plasticizers obtained when 3, 6-endoäthyleno-1, 2, 4, 5-cyclohexanetetracarboxylic acid dianhydride with alcohols containing at least 6 carbon atoms at temperatures between 150 and 250 ° C in a known manner.

A particularly simple embodiment of the method consists in that the alcohol presented and the 3, 6-endoäthyleno-1, 2, 4, 5-cyclohexanetetracarboxylic acid dianhydride is admitted. The molar ratio of the components dianhydride and alcohol can be in wide limits fluctuate. An excess of up to four times the alcohol is expedient Molar amount; it is preferable to work with tube shots of 2 to 3 moles of alcohol. The alcohols that can be used include: cyclohexanol, 2-ethylhexanol, Nonanols, decanols, tridecanols and benzyl alcohol. The reaction temperature is between 150 and 250 ° C; preferably one works at the boiling point of the respective Alcohol with back nuts. You can do the reaction both at normal pressure and under under reduced pressure and, if desired, also under increased pressure. That at the reaction, which takes place in 5 to 20 hours, usually in 10 to 15 hours, resulting Water escapes in vapor form without the need for an entrainer or a catalyst is ; but such can also be included if desired. be applied, such as B. p-toluenesulfonic acid, Sulfuric acid and hydrochloric acid. The presence of inert gases such as B. nitrogen or Carbon dioxide is useful to achieve a good color number for the ester.

The new substances are not very volatile due to their high molecular weight and can also be used as an excellent plasticizer, which is one more optionally have a desired crosslinking effect, can be used; for example films of high mechanical strength with good heat resistance can thus be produced produce. Furthermore, the new esters can also be used as components for Use manufacture of unsaturated polyester resins.

In recent years, plasticizers with excellent electro-insulating properties found use. A characteristic representative this ester is tetra (2-ethylhexyl) pyromellitate.

As the following test report shows, over- meet in this regard the compounds to be prepared according to the invention also contain this plasticizer.

Test report The properties of the invention, as plasticizers suitable tetracarboxylic acid esters have the properties of tetra- (2-ethyl-hexyl) -pyromellitate compared according to the method given in French patent specification 1230 827.

The plasticizing esters and the other ingredients became powdery Polyvinyl chloride added and incorporated on differential rollers.

Foils were made from this plastic mass, from which Plates about 2.5 mm thick for use in Test 5 were molded. Found it two compositions A and B use. A refers to a standard mixture, B is a mixture for electrotechnical purposes.

Table I. AWAY Components Common electrical Mixtures technical (Parts) (parts) Polyvinyl chloride ........ 60 65 Plasticizers .......... 40 35 Barium felled together Cadmium laurate (Stabilizer) ....... 1- Tribasic lead sulfate (Stabilizer).....-- Clay (filler ................ - 15 Wax (lubricant) ..- 0, 3 The following were tested: TOP tetra- (2-ethyl-hexyl) -pyromellitate, BTA NON 3, 6-endoethyleno-1, 2, 4, 5 tetraisononyl cyclohexanetetracarboxylate.

The following tests were carried out: Test 1 volatility with Activated carbon.

Test pieces with a side length of 50.8 mm are weighed, between 5, 08 cm thick layers of activated charcoal and placed in tightly closed glass containers heated to 90 ° C for 24 hours and 4 days. Then the samples are taken out and cleaned them of coal dust and weigh them again.

Test 2 extraction with soapy water.

Samples with a side length of 76.2 mm are placed in 1% strength aqueous solution of soap and keeps it at 90 ° C for 24 hours. Then the samples are washed thoroughly, dries and weighs them again.

Test 3 extraction with hexane.

Weighed samples are placed in clear, lead-free hexane for 2 hours Submerged at 25 ° C, dried well and weighed again.

Test 4 Torsional modulus at low temperatures.

A 5.70.6 cm test piece is cut out of the material and affixed to a "Tinius-Olsen-Tester". which makes the torsional modulus more plastic Measures substances at different temperatures. The temperature at which a sample takes Torsional modulus of 9450 kg / cm2, known as T, or T94so, is determined. This corresponds roughly to the »brittle- keitpunkt ", the one with the" cantilever apparatus " is determined.

Test 5 Electrical Properties.

The electrical properties of the molded bodies produced are tested by determining the specific resistance. It has been shown that the resistivity is highly correlated to volume resistance.

The tests are carried out on a test piece that is placed in an »ASTM cavity mold 4 "and that is 15, 24-15, 24-about 0, 1905 cm tall. Silver-plated electrodes are attached centrally on both sides of the specimen.

Using a vacuum tube electrometer, a shunt and a direct current source, the resistance of the sample is determined. In more detail this test is described in "Rubber Age", pp. 105 to 108, April 1956 (C. E. Balmer and R. F. Conne), as well as in "Resin Review", pp. 3 to 9, Vol. 6, No. 1, Rohm & Haas Company. The electrical properties related to volume resistance are checked by placing the standard samples on a certain number of tests subject to the resistivity. The samples are at the following temperatures tested: (a) 90 ° C.

(b) 60 ° C, immediately after immersion in 60 ° C for 20 hours Water.

The following Table II illustrates mechanical, physical and electrical properties of the tetraesters according to the invention in comparison to tetra- (2-ethyl-hexyl) -pyromellitate.

Table II Resistance properties .. Electrical preservation of the electrical % Weight loss Property property Soft elasticity More specifically, 24 hours in water Volatility at lower macher resistance at 75 ° C with activated charcoal soap temperature Hexane (Ohm / cm # 1012) More specific resistance 24 hours 4 days at 90 ° C 90 ° C 60 ° C at 90 ° C j at 90 ° C dry! wetj (ohms / cm-10 ") Item 0, 6 0, 9 33 16, 0 4, 5-21 BTA NON 0 j 0 j-0 to 0, 04 1, 5'0 02, 1 0, 8 EXAMPLE 1 The parts given in the example are parts by weight.

864 parts of isononanol are placed in a 2 l round bottom flask and with 248 parts of 3, 6-endoäthyleno-1, 2, 4, 5-cyclohexanetetracarboxylic acid dianhydride heated under nitrogen to a boiling point of 213 ° C. Under reflux this temperature is maintained for a further 10 hours, the acid number being the Value 10 reached. The reaction mixture is cooled and neutralized by addition of 1300 parts of 3% aqueous sodium hydroxide solution at 80 ° C using a vibromixer, which takes about 20 minutes, washes the after separation of the two phases Ester twice with 800 parts of water each time and frees the organic phase in one go Thin film evaporator at a temperature of 180 ° C and 0, 5 torr of volatile Shares. the Yield of 3, 6-endoäthyleno-1, 2, 4, 5-cyclohexanetetracarboxylic acid tetraisononyl ester is 725 parts, corresponding to 92% of theory. The molecular weight is 788.

Analysis values and physical data: Calculated ... C74, 0, H 10, 6, O 16.1%, esterification number 284; found ... C 73.8, H 10.3, O 16.3%, esterification number 289

Acid number = 0.5, hydroxyl number = 0, viscosity (20 ° C) = 4255 cP, Refractive index (20 ° C) = 1.4774, density (20 ° C / 4 ° C) = 0.99959, pour point = -12.5 ° C.

Example 2 780 parts of 2-ethylhexanol are placed in a stirred vessel and with 248 parts of 3, 6-endoäthyleno-1, 2, 4, 5-cyclohexanetetracarboxylic acid dianhydride under Nitrogen heated to the boiling point of 183 ° C. Under boiling at the Rückiluß is Maintain this temperature until the acid number reaches 10. The reaction mixture is cooled and neutralized with thorough mixing by adding 1300 parts of 30% aqueous sodium hydroxide solution at 80.degree. The neutralization takes about 20 minutes. After separating the two phases, the ester becomes twice washed with 800 parts of water and then in a thin film evaporator at a temperature of 180 ° C and under a pressure of 0, 5 torr by addicts Shares exempt.

The yield of 3, 6-endoäthyleno-1, 2, 4, 5-cyclohexanetetracarboxylic acid tetra- (2-ethylhexyl) ester is 674 parts, corresponding to 92% of theory. The molecular weight is 732.

Analysis: Calculated ... C 72.1, H 10, 4.017, 5 ° / os found ... C72, 0, H 10.6, O 17.8%.

Claims (1)

Claim: Process for the production of suitable plasticizers 3, 6-Endoäthyleno-1, 2, 4, 5-cyclohexanetetracarboxylic acid esters, d a d u r c h g e It is not possible to indicate that 3, 6-endoäthyleno-1, 2, 4, 5-cyclohexanetetracarboxylic acid dianhydride is used with alcohols containing at least 6 carbon atoms at temperatures between 150 and 250 ° C in a known manner. Publications considered: German Patent No. 526 138; French Patent No. 1 230 827; U.S. Patent No. 2,850 523; Liebigs Annalen der Chemie, Vol. 490 (1931), p. 266.