CS231224B1 - Organosilicon esters and process for their preparation - Google Patents

Abstract

The method of preparing organosilicon esters according to the invention by reacting dichlorodiphenylsilane with polyethylene glycol ethers or polypropylene glycol ethers or their mixtures and by reacting phenyltrichlorosilane with monohydric alcohols in such a way that diphenyldichlorosilane reacts successively with polyalkyl glycol ethers, then with phenyltrichlorosilane and monohydric alcohols at a temperature of 15 to 160 °C, after the reaction is complete, the hydrogen chloride content is reduced by displacement and a solution of sodium hydroxide in the alcohol used is added, after which the volatile components are distilled off. The esters obtained according to the invention are very stable and usable in a wide temperature range not only separately in lubrication technology, but also in a mixture with siloxane, diester and mineral oils.

Description

The invention relates to organosilicon esters and a method for their preparation from diphenyldichlorosilane, polyethylene glycol ethers, polypropylene glycol ethers, phenyltrichlorosilane and monohydric alcohols. The new esters are suitable for use in lubrication technology and could not be further developed.

used in the plastics industry as a plasticizer.

The ever-increasing requirements for the parameters of equipment, machines and engines, especially aircraft engines, also create increased requirements for lubricating oils. For the purposes of lubrication technology, many types of oils have been tested, from mineral to esters of organic alcohols and mono- or dicarboxylic acids to organosilicon compounds. The disadvantageous properties of methyl phenyl aloxanes themselves were eliminated by the later discovered alkoxysilanes with lower alkyls. The compounds mentioned are commonly prepared β using solvents and hydrogen chloride acceptors. Amines such as pyridine, aniline, triethylamine, etc. are usually used as acceptors. When they are used, a large amount of bulky salt is formed, so it is necessary to use a large amount of solvent both to allow homogenization of the reaction mixture and to isolate the esters from the salts.

A large amount of hydrochloride of the base used is formed, which is a ballast substance. For this reason, the procedure is unacceptable for industrial practice. The problem of preparing the above compounds generally falls under the methods of esterification of halogenosilanes. The conditions of the reactions of alcohols with chlorosilanes are the subject of a number of publications (Organosilicon compounds, part I, Academia, Prague 1965, Ladenburg Ber, 6,379 /1983/). An overview of various methods of esterification of halogenosilanes is also given in Chem. Revs. £2, 97 (1947). For the purposes of lubrication technology, only certain groups of the above substances are suitable. Therefore, new and new liquids with better lubricating properties are constantly being sought.

It has now been found that it is possible to synthesize esters containing an aryl, or haloaryl group, and an alkoxy group with a bulkier substituent in the molecule. This knowledge was used in the preparation of new organosilicon esters according to the invention, for which a new production process was simultaneously developed eliminating the aforementioned disadvantageous conditions in the synthesis of these substances from the use of solvents and hydrogen chloride acceptors.

The obtained esters are very stable from a thermo-oxidative and hydrolytic point of view and have excellent lubricity. They are usable in a very wide temperature range and are well miscible with siloxane, diester and mineral oils. They dissolve additives very well and can therefore be used for the preparation of synthetic oils, hydraulic fluids, plastic lubricants, etc.

New organosilicon esters of theoretical formula

°6» ₅ <p R,0-- Si-X- - Yes — X - or ₂ ^{C6H5 ​} X = -O(CH,.CH„O) 2 i y· or -O(CH.GH ₂ O) _y and it is

— Si--OR,

C,H i o 5

STEED,

R, to R^ are the same or different and represent alkyl with 8 to 14 carbon atoms, x represents 1 to 3, y represents 1 to 5, are prepared according to the invention by reacting diphenyldichlorosilane with polyethylene glycol ethers or polypropylene glycol ethers or mixtures thereof, further with phenyltrichlorosilanes and monohydric alcohols with 8 to 14 carbon atoms, whereby diphenyldichlorosilane is successively reacted with polyalkyl glycol ethers, then with phenyltrichlorosilane and monohydric alcohols at a temperature of 15 to 160 °C, after the reaction is complete the hydrogen chloride content is reduced by displacement with a stream of nitrogen, then a solution of sodium hydroxide in the alcohol used is added and the volatile components are distilled off.

The example below illustrates an embodiment of the invention.

Example of execution

384 g of tripropylene glycol ether was introduced into a 1 L Keller four-necked flask equipped with a stirrer, thermometer, reflux condenser, addition funnel, heating bath and outlet pipe with manometer and, while stirring and simultaneously heating the flask, 253 g of diphenyldichlorosilane, 320 g of a mixture containing 85% decanol and 15% dodecanol, 423 g of phenyltrichlorosilane and 286 g of 2-ethylhexanol were added over 1 h. After adding 2-ethylhexanol, a stream of nitrogen was introduced to the bottom of the flask through a tube and, while stirring and heating the flask to 110 to 120 °C, the acidity content in the flask was reduced by the nitrogen stream within 30 to 60 min to an acid number of 1.0 mg KOH/g. Then, the calculated amount of saturated sodium hydroxide solution in 2-ethylhexanol was added to the flask with stirring. The contents of the flask were then transferred to a vacuum distillation apparatus and the excess alcohol was distilled off at a pressure of 2,100 Pa to a boiling point of 225 0. After cooling, the distillation residue was filtered through paper, yielding 995 g of clear yellowish ester with an acid number of 0.03, η^ ² ^1.495 0, flash point of 227 °C, burning point of 260 °C, pour point of -32 °C, viscosity at 100 °C 25.91 mm ² .s ¹ , at 50 °C 143 mm ² .s ^-1 , at -20 °C 61,400 mm ² .

Claims (2)

1. Organosilicon esters of theoretical formula I Γ C,H C,H _r Ί C,H | 6 5 I 6 5 .65 RO — j Si ---- ¹ I X - Yes - 1 — x-i i í — Shi- -person 4 (I) i I ! OR ₂ C.H, 6 5 i i _{Or 3} L where X = -0(CH ₂ -CH ₂ 0) — y -O(OH-CH ₂ O) CH ₃ or a is the same or different to R^ are the same or different and represents alkyl with 8 to y representing 1 to 5. 14 carbon atoms, x represents 1 to 3, 2. A method for preparing organosilicon esters according to item 1, characterized in that diphenyldichlorosilane of formula II (C _g H ₅ ) ₂ SiCl ₂ (II) is reacted with polyethyleneglycoethers or polypropyleneglycoethers or a mixture thereof, further with phenyltrichlorosilane of formula III CgH ₅ SiCl ₃ (III), with monohydric alcohols with a number of carbon atoms of 8 to 14, whereby diphenyldichlorosilane is gradually allowed to react _with polyalkylglycolethei^, then with phenyltrichlorosilane and monohydric alcohols at a temperature of 15 to 160 ^U C, after the reaction is complete, the hydrogen chloride content is reduced by displacement with a stream of nitrogen, then a solution of sodium hydroxide in the alcohol used is added and the volatile components are distilled off.