CS219574B1 - A method of preparing a mixture of antimony and tin mercaptides - Google Patents

Abstract

The invention relates to a method of preparing a mixture of mercaptides of antimony and tin. It solves the preparation of a mixture of mercaptides of antimony and tin in one operation. It consists in the preparation of a mixture by the reaction of mercaptoacetates with a mixture of antimony and dibutyltin oxide in the presence of a dibasic organic acid. The mixtures of the stage of the invention — dibutyltin bis-isooctylmercaptoacetate and trisisooctyl antimony mercaptoacetate — can be used as thermal stabilizers in the processing of polyvinyl chloride.

Description

219 574 [54] Preparation of antifungal and mercaptide mixtures thereof 1

The invention relates to a process for the preparation of antimony and tin mercaptide mixtures.

Antimony and tin mercaptides are widely used as effective polyvinyl chloride heat stabilizers. It has been found that their blends exhibit at least the same effect in controlling polyvinyl chloride as the antimony and tin mercaptides themselves.

These mixtures can be prepared by over-proportions. A disadvantage of the known processes is that it is first necessary to prepare the individual components, i.e. the antimony mercaptide and the tin-tin capide, from which mixtures of certain proportions are formed by mechanical mixing. This entails the drawbacks of a process step of several stages.

These disadvantages are eliminated by the invention of the preparation of mixtures of mercaptide, anti-mono and tin containing mercaptide anti-mono of formula I

Sb (S-CH2-COOiC H17) 3 (I)

and tin mercaptide of formula II (C 4 H 9] 2 Sn (S-CH 2 -COOH 2 O 3) (II) in a weight ratio of, for example, 20:80 to 80:20, wherein the compound of formula III-HS-CH 2 -COOiC 8H71 (III) reacted with a mixture of anti-mono-oxide and dibutyltin oxide in a molar ratio of 1: 9.1 to 1.7: 1 in the presence of 0.1 to 5.0% by weight of citric acid; under vacuum (13.3 to 2.7 kPa) removal of reaction water.

The oxidation resistance of crude products can be enhanced by the addition of conventional phenolic antioxidants such as 2,6-di-tert-butyl-4-methylphenol or phosphite antioxidants such as tris (nonylphenyl) phosphine to the crude product.

The present invention has many advantages over conventional methods. In particular, it is possible to produce a mixed stabilizer in one boiler using one continuous operation; there is no need for several reaction vessels to carry out the invention, as has been the case hitherto. This results in the advantages of, for example, the lower equipment costs, the ease of operation and the management of the entire process, with a consistent quality and riot product.

The following examples explain, but do not limit, the preparation and properties of the compositions of the invention. Example 1

44.32 g (0.22 mole) of iso-octyl mercaptoacetate and 0.12 g of citric acid are metered into a 100 ml reactor equipped with a condenser, the addition of reaction water, a 2 thermometer, a stirrer and a conduit. The mixture was gently bubbled with nitrogen. With vigorous stirring at 25 ° C, the mixture of antimony trioxide and dibutyltin oxide, i.e. 5.97 g (0.0205 mol) of Sb 2 O 3 and 11.68 g (0.0469 mol) of Bu 2 O 2 were metered in. After charging the mixture of oxides, the nitrogen flow is switched off and under a vacuum of 10.664 to 13.333 kPa the reactor is heated so that water is distilled off. The water will be released as the temperature rises. The water release rate drops to a pressure of 10,664 kPa and a maximum heat of 115 ° C is applied at a maximum vacuum of 2,666 kPa and the temperature is maintained at 115 ° Geist for 30 minutes. The reaction mixture was cooled to 40 ° C and the nitrogen was removed by vacuum. 1,2 g 2,6-diterbutyl-4-methyl phenol is added and stirred for 30 minutes. While stirring, the product was gently bubbled with nitrogen. 1 g of filtration silica was added and the product was filtered through a frit.

Said process allows to prepare a mixed stabilizer

Bu2Sn (S-CH2-COOiCiH17) 2: Sb (S-CH2-COOiC1Hi7) 3 = -50: 50 (wt%) Yield: 97.5%

Elemental analysis:% Sb% Sn calculated 8.27 9.2 found 8.12 9.01 Example 2

Following the procedure described in Example 1, from the following batches: 3.99 g (0.0137 mol) Sb2O331.15 g (0.125 mol) Bu2SnO67.7 g (0.332 mol) HS-CH2-COO1C8H17 0.2 g (acid) a citric acid blend stabilizer Bu2Sn (S-CH2-COOiCsH2) 2: Sh (S-Target2-COOiCsH17) 3 = 80: 20 (% by weight);

Elemental analysis:% Sb% Sn calculated 3.31 14.74 found 3.25 14.55 Example 3

Following the procedure described in Example 1, 15.94 g (0.0547 mol) Sb2O3 7.79 g (0.313 mol) Bu2SnO79.83 g (0.3907 mol) HS-CH2-COOiC8HJ7 0.2 g acid citrónovej

Claims (1)

219 574 m < 2 > m & m < tb > ______________________________________ < tb > ______________________________________ < tb > 20: 80 (< / RTI > w / w) Yield: 97.1% Elemental Analysis: Calculated% Sb% Sn13.2 3.69 13.25 3.59 SUBJECT OF THE INVENTION Process for the preparation of mixtures of anti-mono and tin mercapeptides containing mercaptides of anonone of formula I Sb (S-OHa-COOiC8H17) 3 (tin and mercaptides of tin of formula II (C " H9) 2 Sn (S-CH2-COOlC8H17) 3 (II) in a ratio of 20:80 to 80:20, by reacting the compound of formula III HS-CH2-COOiC8H7i (III) with an anionic oxide mixture and dibutyl oxide in molar ratio 1: 9.1-1.7: 1 in the presence of 0.1-5.0% by weight of citric acid], at 25-115 ° C with the evacuation of the reaction water at pressure 13.3 to 2.7 kPa