CS239127B1 - Organotin compounds and processes for their preparation - Google Patents

Abstract

Biocidally effective organotin compounds of general formula I. These new compounds based on the condensate of a copolymer of sulfonated styrene and divinylbenzene with organotin compounds of general formula III or IV are characterized by high efficiency against a wide range of microorganisms from bacteria to algae. They are useful in particular for the preservation of liquids used for cooling machine tools and tools and for many other purposes.

Description

The invention relates to biocidally active organotin compounds of the formula I

S0 ₃ Sn (R) ₃ S0 ₃

(AND).

wherein R is alkyl of two to six carbon atoms or aryl of one to two benzene nuclei. The invention also relates to a process for the preparation of these novel compounds.

The importance of organotin compounds, as is known, lies in their antimicrobial to biocidal activity. This activity is very broad and includes bacteria, yeasts, algae, fungi, wood-decaying fungi and the like. Trialkyltins are used as herbicides, rhodendorepelents, insecticides, etc. Organotin compounds have found wide application in practice due to their activity. They are currently used for preventive protection of various materials239 127

- 2 woods, such as wood, paper, plasters, masonry, textiles, etc. to prevent fungal and other microbial attack. Organotin compounds are also used to preserve coolants, such as water in surface coolers or water-oil emulsions, for cooling and lubricating cutting or forming tools. Water-surface emulsions, without the addition of preservatives, rapidly overgrow with algae. Water-oil emulsions, especially for the cooling and erasing of machining or forming tools, deteriorate relatively rapidly without the addition of preservatives due to the multiplication of microorganisms, making them unusable for cooling and harmful to health. Frequent replacement of cooling emulsions in one to three weeks results in considerable national economic losses, endangers the working environment and often leads to waste water pollution.

A shortcoming of the prior art is that the organotin compounds used to preserve the water-oil emulsion volatilize relatively rapidly, thereby reducing their effective concentration. Thus, in order to provide the necessary biocidal concentration, these compounds need to be continuously supplied to the cooling fluids. This is a relatively complex manipulation since the organotin compounds are highly toxic in the concentrated state. More recently, mercury compounds have been used to preserve emulsions. These means pose a health risk and endanger the working environment when used for a long time. Furthermore, they are not applicable in the case of machining of aluminum and its alloys which disturb it. Also these substances are poisonous, which causes problems in their metering into emulsions. A common drawback of all types of said compositions contained in treated liquids is that their remainder, due to their toxicity, greatly increases the risk of wastewater pollution and increases disposal costs.

The deficiencies of the prior art are overcome by the invention of the biocidally active organotin compounds of the formula I. The process for the preparation of the biocidally active organotin compounds of the formula I according to the invention consists in the formation of a sulfonated styrene copolymer of the formula II

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(II)

with ₃ h is treated with an organotin compound of formula III

Sn (R) ₃ (III), wherein R is the same as in Formula I or Formula IV

Sn (R) ₃ X (IV), wherein R is the same as in Formula I and X is halogen, especially chlorine or bromine, in the molar ratio of copolymer of formula II to compounds of formulas III and IV 1: 1 to 1: 100 ALIGN!

Practical importance and advantage of the novel organotin compounds of the invention, which are prepared by condensation of the available organotin compounds, preferably trialkyl tin compounds, with copolymers f

sulfonated styrene and divinylbenzene consist in the fact that they are insoluble in water, acids, alkalis, common organic solvents and oils, do not volatilise and are stable in the long term. The biocidally active organotin compounds of the invention retain the significant biocidal effects of conventional organotin compounds. They are effective in a wide range of bacteria, fungi, algae and in many cases their effect is immediate. They are not toxic to mammals and

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- 4 treatment of 8 is very, safe. Due to their properties, these compounds are particularly suitable for the preservation of water and water-oil emulsions, where decontamination (bacteria, algae, molds, etc.) occurs on the basis of an oligodynamic effect. The biocidal effects of the compounds according to the invention increase with the tin content which depends on the degree of hydrogen substitution of the sulfone groups with organotin residues, i.e. the degree of the condensation reaction.

Of the organotin compounds, tributyltin tin compounds such as bistributyltin oxyd, tributyltin chloride or bromide and, in the copolymer group, a copolymer of sulfonated styrene and divinylbenzene are particularly preferred.

The following examples illustrate the process without limiting it.

Example 1 kg of a dry granulate of a copolymer of sulfonated styrene and divinylbenzene (a sulfonated styrene polymer that is crosslinked with divinylbenzene to such a degree that the resulting product is insoluble in conventional solvents) with a particle size of 0.3 to 1.0 mm was wetted with distilled water brought to a swollen state and washed away from impurities. The excess water was removed by centrifugation and the swollen damp particles were introduced into a rotating spray bottle. After hermetically sealing, the vessel was rotated and sprayed onto the stirred particles with a solution of 10 g of bistributyltin oxide in 10 ml of ethanol over 13 minutes. After stirring for 30 minutes, the particles were removed from the vessel and used to preserve the water-oil emulsion in the machine tool.

Example 2

The organotin compound prepared according to Example 1 in an amount of 375 ml was placed in a turret lathe so that a 25 liter recirculating water-oil emulsion came into contact with it. After a ten-month operation, the water-oil properties did not change, neither an increased content of the tin compounds in the emulsion nor a corrosive effect, in particular on aluminum workpieces, were found. Microbiological examination revealed that the concentrations of multiplying capable microbial cells, predominantly acinetobacter calcoaceticus, were consistently maintained at 10

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- 5 cells per ml, which is commonly found in the external environment, with no coliform or pathogenic germs detected.

Example 3

The organotin compound prepared according to Example 1 in an amount of 1.1 liters was placed in the circulating water-oil emulsion of the milling cutter. The initial volume of the water-oil emulsion was 42 liters. After one month of operation, when the emulsion showed no changes, 100ml of contaminated emulsion from another machine that had already smelled was added. Within 10 minutes the water-oil emulsion was decontaminated and the odor disappeared. The water-oil emulsion was not replaced during the next 9 months of operation of the cutter, which was only replenished to the original volume. The microbial contamination of the water-oil emulsion was maintained at approximately 10 cells per ml without coliform or pathogenic germs.

Claims (2)

OBJECT OF THE INVENTION Biocidally active organotin compounds of formula I SO ₃ Sn (R) ₃ (I) in which R represents alkyl of two to six carbon atoms or aryl β of one to two benzene nuclei · Process for the preparation of the biocidally active organotin compounds of the formula I according to claim 1, characterized in that the copolymer of sulfonated styrene and divinylbenzene of the formula II - 7 239 127 acts with an organotin compound of formula III ^with n (R) ₃ J ₂ 0 (III), in which R denotes the same as in formula I or formula IV Sn (R) ₃ X (IV), wherein R denotes the same as in formula I and X denotes a halogen atom, especially chlorine or bromine, in the molar ratio of the copolymer of formula II to the compounds of formulas III and IV 1: 1 to 1: 100 .