RU2039738C1 - Mono-3- (3,5-di-tert-butylphenyl) -thiopropionate -2,2-methylene- -bis- (6-tert-butyl-4-methylphenol) as stabilizing agent for rubber ски-3 - Google Patents

Abstract

FIELD: organic chemistry. SUBSTANCE: product: mono-3- (3,5-di-tert.-butylphenyl) -thiopropionate-2,2-methylene -bis- (6-tert.-butyl-4-methylphenol), empirical formula is C₄₀H₅₆O₄S, yield is 98.7% purity is 99% Reagent 1: 4-mercapto-2,6-di-tert. -butylphenol. Reagent 2: 2,2′-methylene-bis-(6-tert. -butyl-4-methylphenol). Reaction conditions: in the presence of potassium fluoride as catalyst, at 10-50 C, in acetonitrile medium, at molar ratio mercaptophenol/acrylate/catalyst 1:(1-1.2):(0.01-0.14). EFFECT: increased effectiveness of agent. 3 tbl

Description

SCH₂CH₂R

в качестве стабилизатора для СКИ-3.The invention relates to organic chemistry, namely to a new derivative of 3- (3,5-di-tert-butylphenyl) thiopropionic acid of the formula:
HO

SCH ₂ CH ₂ R

as a stabilizer for SKI-3.

SCH₂CH₂R где R= -CN, -COOCH₃
Производное получают взаимодействием 4-меркапто-2,6-ди-трет-бутилфенола с виниловыми соединениями при температуре 0-80^оС, в среде i-PrOH, EtOH, MeOH, CH₂Cl₂, CH₃CN, в присутствии в качестве катализаторов третичных аминов. Продукт выделяется с количественным выходом [1]
Недостатками способа являются сложность выделения целевого продукта и отделения растворителя от катализатора путем многоступенчатой ректификации.A known derivative of 3- (3,5-di-tert-butylphenyl) thiocarboxylic acid of the formula:
HO

SCH ₂ CH ₂ R where R = -CN, -COOCH ₃
Derivative is prepared by reacting 4-mercapto-2,6-di-tert-butylphenol with vinyl compounds at a temperature of 0-80 ^{° C,} in a medium i-PrOH, EtOH, MeOH, CH ₂ Cl _2, CH ₃ CN, in the presence of a tertiary amine catalysts. The product is released in quantitative yield [1]
The disadvantages of the method are the difficulty of isolating the target product and separating the solvent from the catalyst by multi-stage distillation.

Stabilizers for polymers are also known, such as ionol (Alkofen BP), stabilizer NG-2246 (Bisalkeofen BP) [2]
But these stabilizers are volatile, especially when using rubber filled with a stabilizer at elevated temperatures, which accordingly affects the physical and mechanical properties of the rubber.

 The aim of the invention is to obtain a new stabilizer based on 4-mercapto-2,6-di-tert-butylphenol with higher stabilizing properties.

The goal is achieved in that 4-mercapto-2,6-di-tert-butylphenol is reacted with 2,2'-methylene-bis- (6-tert-butyl-4-methylphenol) monoacrylic ester in the presence of potassium fluoride as catalyst at a temperature of 10-50 ^{° C} in an organic solvent (acetonitrile) with following molar ratio of the catalyst components mercaptophenol acrylate 1: (1-1.2): (0,01-0,14).

The starting reagents must meet the following requirements:
1) 4-mercapto-2,6-di-tert-butylphenol is obtained according to US Pat. U.S. No. 3,479,407;
2) acetonitrile TU 6-09-3534-82;
3) potassium fluoride GOST 20848-75;
4) 2,2'-methylene-bis- (6-tert-butyl-4-methylphenol) monoacrylic ester is prepared according to US Pat. U.S. Patent 4,562,281.

PRI me R 1. Into a flask with a capacity of 50 ml load 2.4 g (0.01 mol) of 4-mercapto-2,6-di-tert-butylphenol, 10 ml of acetonitrile and 0.04 g of potassium fluoride (0 7 x 10 ^-4 mol). With stirring, a solution of 4.0 g (0.01 mol) of 2,2'-methylene-bis- (6-tert-butyl-4-methylphenol) monoacrylic ester in 10 ml of acetonitrile is metered. The mixture was stirred at ²⁵ ° C for 2 hours. The catalyst was filtered off, the filtrate was evaporated, the residue was recrystallized from hexane. Yield 6.3 g (98.7%), purity 99% (HPLC data).

The elemental composition of the resulting product:
Gross formula C ₄₀ H ₅₆ O ₄ S.

 Calculated, C 75.96; H 8.55; S 5.07.

 Found, C, 76.1; H 8.7; S 5.13.

 The structure of the obtained product is proved by the methods of IR and PMR spectroscopy.

In the IR spectrum, absorption is characteristic of the stretching vibrations C = O (1733 cm ^-1 ); OH (3487 and 3637 cm ^-1 ) bonds.

); 2,21 c. 3 H (ArC

); 2,9 т. 2 Н (C

S); 3,1 т. 2 Н (С

-С=О); 3,62 с. 2 Н (ArC

Ar); 5,03 c. 1H (O-

); 5,17 c. 1 H (O-H); 6,8 м. 6 Н (Ar).PMR spectrum, ppm 1.29 m. 36 N (4-t-Bu); 2.13 s 3 N (ArC

); 2.21 c. 3 H (ArC

); 2.9 t. 2 N (C

S); 3.1 t. 2 N (C

-C = O); 3.62 s 2 N (ArC

Ar); 5.03 c. 1H (O-

); 5.17 c. 1 H (OH); 6.8 m. 6 N (Ar).

 Examples with another claimed amount of starting reagents are given in table. 1. The stabilizing ability of the obtained compound is presented in the examples below (in comparison with ionol and NG-2246).

Example 2. After decontamination, an alcoholic solution of mono-3- (3,5-di-tert-butylphenyl) thiopropionen-2,2'-methylene bis- (6-tert) is introduced into the SKI-3 polymerizate -butyl-4-methylphenol) 1 wt. on rubber. The polymer was isolated by first degassing followed by drying in vacuo at 705 ^{° C} for 7 hours. Under the same conditions secrete rubber samples stabilized ionol (compound I) and NG-2246 (compound II). Determine the plasticity conservation index (ICP) by the Wallace velocity method and the induction period of oxidation. The results are presented in table.2.

PRI me R 3. In the SKI-3 polymerizate after deactivation, the test product is introduced analogously to the described example. The polymer is recovered by reprecipitation with ethanol toluene solution of isoprene rubber, followed by pressing and drying in an extruder at a die temperature of 180 ° ^C. Under the same conditions, isolated rubber samples stabilized ionol (compound I) and NG-2246 (compound II). The data for these examples are given in table.3. As can be seen from table 3, the claimed compound in stabilizing ability when drying on an extruder exceeds industrial antioxidants by 1.2 times (compound I) and 2 times (compound II).

 Based on the data presented, it is seen that the resulting product mono-3- (3,5-di-tert-butylphenyl) thiopropionate-2,2-methylene-bis- (6-tert-butyl-4-methane is new in organic chemistry and exhibits stabilizing properties for SKI-3 rubbers.

Claims (1)

Mono-3- (3,5-di-tert-butylphenyl) -thiopropionate-2,2-methylene-bis- (6-tert-butyl-4-methylphenol) of the formula

as a stabilizer for rubbers SKI-3.

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