Process for producing rubber vulcanization accelerant penta-methylene thiuram tetrasulfide

Abstract

The invention relates to a method for preparing a rubber vulcanization accelerator, namely dipentamethylenethiuram tetrasulfide, wherein the method takes water as a solvent; raw materials together with the molar ratio thereof used in the method are: the molar ratio of piperidine to carbon disulfide to sulfur to hydrogen peroxide is 1:1-1.3:1.8-2.5:0.4-0.7; the method comprises the following concrete technological processes: under normal pressure, the piperidine and the sulfur are sequentially added to a reaction kettle holding water in a stirring state; after adding is over, temperature is controlled in a range between 20 and 30 DEG C; then carbon disulfide liquid is dripped, and the dripping time is controlled to be 2 to 3 hours; after dripping is over, the pH value of a reaction solution is measured; after the pH value of the reaction solution is steady in the range between 6.5 and 7.5, the temperature of the reaction solution is controlled between 30 and 40 DEG C; hydrogen peroxide is dipped so as to perform oxidation reaction for 3 to 4 hours; after the oxidation reaction is over, the reaction solution is thermally insulated and reacts for 1 hour; then solid-liquid separation is performed; and an obtained solid is dried, ground, sieved and packaged so as to obtain a product. The method has the advantages that the method is short in production period, high in safety factor, nearly free from exhaust emission, high in product melting point, good in product appearance, high in yield, obviously superior to other preparation methods, low in comprehensive cost and capable of improving product quality, saving energy, reducing consumption and reducing three-waste 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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