Process for producing rubber vulcanization accelerant penta-methylene thiuram tetrasulfide

Abstract

The present invention relates to a kind of preparation method of rubber vulcanization accelerator bispentamethylene thiuram tetrasulfide, wherein said method uses water as solvent, and the raw materials used and their molar ratio are: hexahydropyridine: carbon disulfide: sulfur: hydrogen peroxide =1: 1~1.3: 1.8~2.5: 0.4~0.7, the specific process of the method is: under normal pressure, add hexahydropyridine and sulfur successively in the reaction kettle filled with water under stirring state, after adding Finally, control the temperature within the range of 20°C to 30°C, then add carbon disulfide liquid dropwise, and control the dropwise addition time for 2 to 3 hours. After the dropwise addition, measure the pH value of the reaction solution. After the temperature is stable within the range, control the temperature of the reaction solution at 30°C to 40°C, and start to add hydrogen peroxide dropwise to carry out the oxidation reaction. The oxidation reaction time is 3 to 4 hours; The liquid is separated, and the obtained solid is dried, crushed, sieved, and packaged to obtain the product. The method of the present invention has short production cycle, high safety factor, almost no waste gas emission, high melting point, good appearance and high yield of the obtained product, which is obviously superior to other preparation methods, and the comprehensive cost is low. Adopting the method of the present invention can improve the product Quality, energy saving and consumption reduction, reducing "three wastes" pollution.

Description

1. Technical field: [0001] The invention relates to a preparation method of a rubber vulcanization accelerator, in particular to a preparation method of a rubber vulcanization accelerator bispentamethylenethiuram tetrasulfide. 2. Background technology: [0002] In recent years, with the rapid development of domestic automobile industry and communication industry, etc., it has driven the rapid growth of rubber processing industry and provided unprecedented good opportunities for the development of rubber additives industry. Rubber vulcanization accelerator Dipentamethylenethiuram tetrasulfide (DPTT) is used as an accelerator for natural rubber, synthetic rubber and latex. Because it can decompose free sulfur when heated, it can also be used as a vulcanizing agent. When used as a vulcanizing agent, it is relatively safe at operating temperature, and the vulcanized rubber has excellent heat resistance and aging resistance. This product can be used as the main accelerator in ch...

AI Technical Summary

Problems solved by technology

[0003] The production technology of rubber vulcanization accelerator bispentamethylenethiuram tetrasulfide (DPTT) is generally produced by oxygen method or disulfide dichloride as raw material in China. These processes remove a large amount of organic pollutants during production. Excluding the toxic gas of the solvent; more seriously, because the reaction is carried out under pressure, the reactant in the reactor is a gaseous substance, which is very easy to explode during the reaction process, so there is a great safety hazard in the production process At the same time, the production process consumes a lot of energy and produces a large amount of waste water and waste gas, which brings great difficulties to environmental protection. It is difficult to achieve "clean and green" production, which does not meet the national environmental protection policy and energy-saving production requirements.

In addition, the melting point of the product is low, the appearance is yellow, and the yield is low. It is difficult for the finished product to meet the high-end requirements of the domestic and foreign sales markets.

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