DE2113818A1 - Pb, Ba and La salts of itatonic acid monoesters - Google Patents

Abstract

New cpds. (I) (where M = Pb, Ba or La and R = alkyl, (meth)allyl) are prepared from (I, M = H) and a metal oxide or hydroxide or salt and alkali. Other methods of salt formation hydrolyse the ester. (I) when polymerised or co-polymerised gives hard products having high refractive index and good transparency, useful for lenses and prisms.

Description

Process for the preparation of metal salts of itaconic acid monoester Priorities: Japan dated 24 Harz 1970 No. 25137/70 Japan dated March 24, 1970 No. 25138/70 The invention relates to a process for the preparation of nouon metal salts of Ztaconic acid monoesters and polymers thereof.

Itaconic acid and various thirds of it are currently in strong form Extent as starting materials for the production of a large number of polymers and copolymers used, but were metal salts of itaconic acid monoesters not yet known. In particular, salts of itaconic acid monoesters are difficult using any of the vera procedures that are commonly used to manufacture Salt formation can be used, since the Eaterbindlung undergoes hydrolysis when the ester to the usual salt formation process by neutralization is subjected.

The object of the invention is therefore to provide a method for easy production of metal salts of itaconic acid monoesters, which were not previously known, to deliver.

The metal salts obtained by the process according to the invention of In the polymerization, itaconic acid monoesters give polymers which are excellent Have transparency and a high refractive index. In addition, they provide copolymers, which have various optical properties and excellent hardness, when copolymerized with a vinyl monomer such as methyl methacrylate, styrene or the like will. Furthermore, they are effective as a stabilizer, and they can be mixed with vinyl chloride copolymerized to produce an excellent copolymer of vinyl chloride, which retains the polyvinyl chloride inherent transparency.

Based on the investigation into working methods for the production of metal salts of itaconic acid monoester, which. as starting material for the production of polymers with remarkably excellent optical and physical properties, such as as described above are useful, it has been found that the metal salts of itaconic acid monoester in high yield by converting an itaconic acid monoester with an oxide or hydroxide of lead, barium or lanthanum or by reaction of an itaconic acid monoester with a water-soluble salt of lead, barium or Lanthanum can be produced in the absence of a suitable amount of an alkali.

According to the method according to the invention, MetallsaX of itaconic acid monoester, which is represented by the following formula: wherein M represents one equivalent of one of the metals Pb, Ba or La and R is an alkyl radical, allyl radical or methallyl radical, can be prepared in high yield by an itaconic acid monoester of the formula: in which R has the meaning given above, is reacted with lead, barium or lanthanum as metal in the form of its oxide or hydroxide or with this metal in the form of its water-soluble salt in the presence of alkali.

Those used as starting materials for the process according to the invention Itaconic acid monoesters are compounds well known per se, and they can, for example according to the method described in Journal of Organic Chemistry, 17 (1952), p. 116 being represented.

In the aforementioned formulas, the alkyl radical is the substituent R is preferably a lower alkyl radical, e.g. B. the methyl, ithyl, propyl or butyl radical. When R is the allyl or methallyl radical, has that obtained from the metal salt Polymer has an increased hardness.

In one embodiment of the invention, one after the per se known method obtained itaconic acid monoester in a suitable organic Solvent dissolved, and it becomes an equimolar amount of a metal oxide or Hydroxides, e.g. 3. Add lead oxide, followed by heating for several hours. Preferably, but not necessarily, that formed during heating Water through a suitable agent removed, e.g. B. an azeotropic Distillation. After the completion of the reaction, the solvent is removed to to obtain the desired metal salt of the itaconic acid monoester as a residue. from the metal salts, the lead salt can sometimes be obtained in crystalline form, while the barium and lanthanum salts are usually obtained as a foamy mass which are then spray-dried to obtain a powdered product can. In such a case, the higher the alkyl radical, the more viscous the product, z. B. butyl radical.

The purification of the metal salts obtained in this way can be carried out by dissolving the crude salts in a suitable solvent followed by filtration or centrifugation to remove insoluble salts as by-products and other insoluble ones Substances are carried out. The filtrate or the supernatant liquid will then concentrated under reduced pressure or with heating. Anything left behind Solvent is then completely evaporated from the residue to give the purified Metal salts as white crystals (Pb salt) or as amorphous solids (La and Ba salts) or as viscous substances. In another embodiment of the invention becomes a solution of both itaconic acid monoester and a soluble salt of lead, Barium or lanthanum is mixed with an alkaline solution and the mixture is made left to react for several hours. The resulting transparent solution becomes Removal of insoluble salts as a by-product is filtered, and the filtrate is then worked up in the same manner as above to obtain the desired metal salt des To deliver itaconic acid ester.

The preferred soluble metal salt used in the invention is, includes z. B. lead nitrate, barium chloride, lanthanum chloride or the like. This metal salt is generally in a stoichiometric equivalent amount is used, but it can be used in a slightly excess amount will. The alkaline solution can be an aqueous or alkaline solution of sodium hydroxide, Potassium hydroxide, ammonia, an amine, etc. An anion exchange resin can also be used (e.g. Ämberlite CG LtOO - trade name) in an aqueous or alcoholic medium be used. The alkali or the anion exchange resin is preferably used in an equimolar amount, based on the itaconic acid monoester, applied.

The metal salts obtained by the process according to the invention Itaconic acid monoesters are in methanol, ethanol, acetone, dimethylformamide, dimethyl sulfoxide, Chloroform, dioxane, etc. soluble, but they are generally non-polar Solvent insoluble.

The metal salt of the itaconic acid monoester is easy to polymerize by heating it in the presence of a polymerization catalyst or with Radioactive radiation is irradiated to produce a polymer with a high refractive index to build. The metal salt of the itaconic acid ester can also be used with a vinyl monomer such as methyl methacrylate, styrene or the like. Are copolymerized to form a copolymer with excellent properties. The one in the above-mentioned polymerization The polymerization catalyst used includes radical catalysts such as peroxides or azobisisobutyronitrile. The amount of catalyst is in the range from 0.01 to 0.5% by weight, based on the monomer, i.e. H. the metal salt of itaconic acid monoester. The polymerization temperature is in the range from 40 ° to 120 ° C., preferably from 0 60 ° to 80 0. The polymerization can be carried out in any way, d. H. as block polymerization, solution polymerization, suspension polymerization or the like. The polymerization takes from several hours to several tens of hours carried out with the usual polymerization period nearly 10 hours. The solvents usually used for the polymerization used are used, z. B.

Alcohol, acetone, dimethylformamide, dimethyl sulfoxide and the like.

In case the polymerization is carried out by radioactive irradiation is, the metal salt of itaconic acid monoester as a monomer as such or irradiated in the form of a solution in a suitable solvent while the temperature is kept between 0 0 to 100 0. The preferred radioactive Radiation is Ganima radiation, however other radioactive rays can do that usually used for polymerizations, e.g. B. ß-radiation or neutron radiation be used. The irradiation period depends on the radioactive dose and others Conditions, however, a radiation duration of several hours, i.e. H. 2 to 10 h is usually sufficient.

Although the metal salt of itaconic acid monoester easily through either catalytic polymerisation or radiation polymerisation with radioactive radiation, as described above, is the latter method advantageous as it allows control of the degree of polymerization and other conditions, which influence the properties of the polymer obtained, facilitates. Further, the polymerization can be carried out with a combination of catalyst polymerization and irradiation polymerization are carried out. The metal salts of itaconic acid monoester can be polymerized alone or copolymerized by a combination of two or more different metal salts is applied.

In the copolymerization, a copolymer can be obtained which Has intermediate properties between the various monomers. The polymers including the copolymers which were obtained in this way colorless, transparent and hard resins, and they are optical in terms of their appearance Properties, especially their refractive index compared to those of the conventional ones Remarkably superior to polymers. For example, shows a methyl methacrylate polymer or Polycarbonate (CR 39), which was used as a material for optical elements, a refractive index on the order of only 1.5, while that after the The polymers obtained in the process according to the invention have a refractive index of 1.60 or more and in particular as materials for compression molded optical elements how lenses and prisms are useful.

The invention is explained in more detail below with the aid of examples, without restricting them.

Example 1: (A) One with a mechanical stirrer and a reflux condenser Equipped 1 l flask was filled with 260 g of itaconic acid, v00 g of methanol and 5 g of acetyl chloride filled and the mixture was heated. After all of the itaconic acid is dissolved the solution was refluxed for about 20 minutes and the overflow methanol, hydrogen chloride and methyl acetate were distilled off under reduced pressure. Recrystallization of the residue from benzene gave 230 g (80 above yield) Itaconic acid monomethyl ester.

(B) 144 g of the itaconic acid monomethyl ester obtained above, 114 g of lead oxide and 400 cc of methanol were poured into one with a mechanical stirrer and a reflux condenser equipped 1 1 flask, and the mixture was stirred for 1 h in the Refluxed heat. After the mixture has been allowed to cool, it was filtered and the solvent was removed from the filtrate under reduced pressure Distilled pressure. The residue was dried, giving 226 g (95 goat yield) Lead salt of itaconic acid monomethyl ester as a colorless, transparent, light flowing solids were obtained.

Example 2: One with a mechanical stirrer and a dropping funnel equipped 1 1 flask was filled with 144 g of itaconic acid, 170 g of lead nitrate, 200 ccm Methanol and 200 cc of water, and to the mixture was added dropwise A solution of 67 g of 85% potassium hydroxide in 200 ccm of water was added while cooling with ice. After the addition was complete, the mixture was allowed to stand for about 1 hour and allowed to cool Removal of the by-product potassium nitrate filtered. The solvent was then distilled off from the filtrate under reduced pressure, and the residue became dissolved in methanol, which after removal of insoluble materials by Filtration was then distilled off. The recrystallization of the residue from 800 ccm of methanol-water mixture gave 185 g (75% yield) of a crystalline lead salt of itaconic acid monomethyl ester; Melting point 9 62 - 64 00.

Example 3: A 1 l flask was filled with 47 g of itaconic acid monoethyl ester (produced according to the same procedure as described in Example 1 (A), however using ethyl alcohol instead of methyl alcohol), 50 g lead oxide, 400 cc of ethanol and 200 cc of benzene, and the mixture was refluxed 8 h heated, while the water formed during the heating is removed as an azeotrope was, and the remaining alcoholic solution was cooled, whereby 66 g (85% yield) of the lead salt of itaconic acid monoethyl ester were obtained. The resulting salt was insoluble in cold benzene, but soluble in chloroform; Melting point = 81-8300.

Example 4: 158 g of itaconic acid monoethyl ester, 170 g of lead nitrate, 67 G 85% potassium hydroxide and one consisting of ethanol and water Solvent systems were reacted in the same manner as in Example 2. After the solvent system from the reaction mixture under reduced pressure had been distilled off, the residue was dissolved in ethanol in the heat, followed by filtration to remove insolubles, and the filtrate was cooled, giving 214 g (82 above yield) of a crystalline lead salt of itaconic acid monoethyl ester were obtained.

Example 5: 186 g of itaconic acid mono-n-butyl ester (prepared according to the same Procedure as described in Example 1 (A), but using n-butyl alcohol instead of methyl alcohol), 170 g lead nitrate, 67 g 85 gOiges potassium hydroxide and a solvent system consisting of ethanol and water were made in the same way reacted as in Example 2. After the completion of the reaction, EaMl1mnitrate removed as a by-product by filtration and the solvent was removed from the The filtrate was distilled off under reduced pressure. The resulting residue was dissolved in ethanol, which after filtration to remove insoluble substances Was distilled off under reduced pressure, with 247 g (88% yield) of the desired lead salt of itaconic acid mono-n-butyl ester were obtained. That so obtained product was a colorless, viscous liquid and it was soluble in benzene.

Example 6: A 1 l flask equipped with a mechanical stirrer was with 170 g of itaconic acid monoallyl ester (prepared according to the same procedure as described in Example 1 (A), but using allyl alcohol instead of methanol), 114 g lead oxide and 400 cc methanol as solvent and the mixture was reacted in the same manner as in Example 1 (B) calmly. Working up the mixture obtained as before gave 246 g (93% strength Yield) of a lead salt of itaconic acid monoallyl ester. . The product was one colorless, viscous liquid and it was soluble in benzene.

Example 7: (A) One equipped with a calcium chloride drying tube 500 cc flask was filled with 224 g of anhydrous itaconic acid, 160 g of hethallyl alcohol and 2 cc of acetyl chloride filled, and the mixture was at a temperature between Heated to 60 ° C and 70 ° C for about 1 hour and then to 80 ° C for 10 minutes. After letting it cool down 300 cc of toluene was added to the mixture, which was then used to remove insolubles Substances was filtered, and the filtrate was sharply cooled with dry ice-ethanol, to obtain a crystalline product. Recrystallization of the resulting product from toluene gave 153 g (85% yield) of crystalline itaconic acid monomethallyl ester.

(B) 184 g of the monomethallyl itaconate obtained above, 114 g of lead oxide and 400 cc of methanol were allowed to react with one another and then in worked up in the same way as in Example 1 (B), with 256 g (92% yield) of a lead salt of itaconic acid monomethallyl ester. The resulting Product was a colorless, viscous liquid and was soluble in benzene.

Example 8: Following the procedure described in Example 1 (B) 186 g of itaconic acid mono-iso-butyl ester (prepared according to the same in example 7 (A) described procedure, but using isobutyl alcohol instead of methallyl alcohol), 114 g of lead oxide and 400 cc of methanol react left, with 252 g (90% yield) of a lead salt of itaconic acid mono-iso-butyl ester were obtained as a colorless, viscous liquid.

Example 9: A 1 liter flask equipped with a mechanical stirrer was with 144 g of itaconic acid monomethyl ester, 77 g of barium oxide and 400 ccm of methanol filled, and the mixture was reacted for 1 hour while cooling with water and stirring calmly. After the completion of the reaction, the reaction mixture was used for removal insolubles filtered, and the solvent was taken from the filtrate distilled off under reduced pressure.

The resulting residue was dried, 187 g (92 goat yield) of a barium salt of itaconic acid monomethyl ester as a white, amorphous solid were obtained.

Example 10: Following the procedure described in Example 9 158 g of itaconic acid monoethyl ester, 77 g of barium oxide and 400 ccm of ethanol were reacted left, 197 g (90% yield) of a barium salt of itaconic acid monoethyl ester were obtained as a white, amorphous solid.

Example 11: One with a mechanical stirrer and a dropping funnel equipped 1 1 flask was with 188 g of itaconic acid mono-n-butyl ester, 125 g of barium chloride, 350 cc of methanol and 50 cc of water were filled, and the mixture was added dropwise a solution of 67 g of a potassium hydroxide in 200 cc of methanol with ice cooling added. After the addition was complete, the mixture was allowed to stand for about 1 hour left and filtered to remove the by-product potassium chloride. The solvent was therefrom the filtrate under reduced Distilled off pressure, and the residue was dissolved in methanol. After filtration to remove insolubles Methanol was distilled off, and the residue was dried, leaving 208 g (87 goat yield) of a barium salt of itaconic acid mono-n-butyl ester were obtained became. The resulting product was a colorless, easily flowable festival.

Example 12: Following the procedure described in Example 11 170 g of itaconic acid monoallyl ester, 125 g of barium chloride and one of methanol and a small amount of water allowed to react the existing solvent system, 206 g (90% yield) of a barium salt of itaconic acid monoallyl ester were obtained. The resulting product was a colorless, easily flowable one Solid.

Example 13: One with a mechanical stirrer and a dropping funnel Equipped 1 1 flask was with 64 g of lanthanum chloride heptahydrate, 72 g of itaconic acid monomethyl ester and 500 com of methanol, and a solution was added dropwise to the mixture of 33.5 g of an Ealius hydroxide in 200 cc of methanol were added while cooling with ice. After the addition was complete, the mixture was allowed to stand for about 1 hour and allowed to cool Removal of the by-product potassium chloride is filtered off. The solvent was then distilled off from the filtrate under reduced pressure, and the residue became dissolved in methanol followed by the addition of benzene. After filtration for removal soluble substances, the solvent was distilled off under reduced pressure, and the residue was dried to obtain 94 g (92% yield) of a lanthanum salt of itaconic acid monomethyl ester as a white, amorphous solid.

Example 14: Following the procedure described in Example 13 64 g of lanthanum chloride heptahydrate, 79 g of itaconic acid monoethyl ester, 33.5 g of 85 % potassium hydroxide and ethanol allowed to react as a solvent, 97 g (89 ° yield) of a lanthanum salt of itaconic acid monoethyl ester as a white, amorphous solid.

Example 15: Following the procedure described in Example 13 were 64 g of lanthanum chloride heptahydrate, 85 g of itaconic acid monoallyl ester, 33.5 g of 85 % potassium hydroxide and ethanol allowed to react as a solvent, with 105 g (91 yield) of a lanthanum salt of itaconic acid monoallyl ester were obtained. The product thus obtained was colorless, transparent, light, or weak flowable solid, and at about 70 ° C it became a viscous liquid, which exhibited increased flow.

Example 16: Following the procedure described in Example 13 were 64 g of lanthanum chloride heptahydrate, 92 g of itaconic acid monomethallyl ester, 33.5 g of 85% potassium hydroxide and ethanol allowed to react as a solvent, wherein 110 g (90 above yield) of a lanthanum salt of itaconic acid monomethallyl ester were obtained. The product thus obtained was colorless, transparent, light flowing solid, and it became a viscous liquid at approximately 70 ° d, which exhibited increased flow.

Example 17; 10 g of the lead salt of itaconic acid monomethyl ester prepared in Example 1 were poured into a probe tube, and after heating to a temperature of 70 ° C to 80 ° C for 5 minutes, the tube was sealed under reduced pressure.

The probe tube was then held while the temperature was around 30 ° C with gamma rays of 60Co, which had a radioactivity of 3000 Ci, irradiated at a distance of 50 cm for 10 h, whereby the ester polymerizes became.

After this period of irradiation, the resulting polymer became Heated for 1 hour at a temperature of 115 ° C to give a colorless, transparent polymer with a refractive index of 1.61.

Example 18: Following the procedure described in Example 17 10 g of the lead salt of itaconic acid monomethallyl prepared in Example 7 were obtained polymerized in the probe tube, a colorless, transparent polymer obtained became.

Example 19: 10 g of the lead salt of itaconic acid monoethyl ester prepared in Example 3 and 10 g of the lanthanum salt of itaconic acid monoethyl ester prepared in Example 14 were dissolved in 20 cc of methanol, and the methanol was then reduced under reduced pressure Pressure evaporated to give a colorless, viscous mass. The resulting viscous mass, was then polymerized in the same manner as in Example 17, wherein obtained a colorless, transparent copolymer with a refractive index of 1.58 became.

Example 20: 10 g of the lead salt of Itaconic acid monoethyl ester and 5 g of the barium salt prepared in Example 10 of itaconic acid monoethyl ester was dissolved in 10 g of styrene, followed by addition of 20 mg of azobisisobutzronitrile, and the mixture was then at a temperature of 50 0G under reduced pressure for 20 h. After completion of the Reaction, the mixture was heated to a temperature of 90 oC for 3 h, with a colorless, transparent copolymer was obtained.

Example 21: 10 g of the lead salt of itaconic acid monoallyl ester prepared in Example 6 were dissolved in 10 g of methyl methacrylate, and the solution was in a test tube housed, which was then sealed under reduced pressure. The pipe was then at 20 ° a with radioactive radiation from 60Co with a radioactivity fully irradiated 3000 Ci at a distance of 100 cm for 40 h. After this exposure period the resulting polymer was heated to 80 0 h for 10 h, a colorless, transparent Copolymer was obtained, which has a high hardness and a refractive index of 1.55 owned.

Example 22: 5 g of the lead salt of itaconic acid monobutyl ester prepared in Example 5, 20 g of vinyl chloride, 50 cc of benzene and 30 mg of azobisisobutyronitrile were in a Filled into the autoclave. The mixture was then at a temperature of 50 0C during Allowed to polymerize for 15 h with stirring. After the completion of the polymerization was the precipitated polymer isolated by filtration, 20 g of a copolymer -were obtained, which has excellent heat stability, weather resistance and Possessed transparency.

According to the invention, metal salts of itaconic acid monoesters are thereby obtained obtained that an itaconic acid monoester with an oxide or hydroxide of lead, barium or lanthanum is reacted, or that an itaconic acid monoester with a water-soluble Salt of lead, barium or lanthanum reacted in the presence of an alkali will. The metal salts of itaconic acid monoester thus obtained are furthermore in the presence a polymerization catalyst heated or irradiated with radioactive radiation, whereby a polymer with a high refractive index is produced.

Claims (2)

P a t e n t a n s p r ü c h e 1. A method for producing metal salts of itaconic acid monoesters which are represented by the following formula; wherein M represents an equivalent of the metals Pb, Ba or La and R is an alkyl radical, an allyl radical or a methallyl radical, characterized in that an itaconic acid monoster represented by the following formula wherein R has the meaning given above, is unset with an oxide or hydroxide of lead, barium or lanthanum. 2. Process for the preparation of metal salts of itaconic acid monoesters the formula given in claim 1, characterized in that an itaconic acid monoester of the formula given in claim 1 with a soluble Salt of one of the metals lead, barium and lanthanum in the presence of alkali, unsettled will.