Method for synthesizing sulfur-containing silane coupling agent from sodium polysulfide

Abstract

The invention relates to a method for synthesizing a sulfur-containing silane coupling agent from sodium polysulfide, belonging to the technical field of organic chemistry. The method comprises the following steps: reacting sodium hydroxide and sulfur to prepare sodium polysulfide, and synthesizing the sulfur-containing silane coupling agent from the sodium polysulfide. The invention solves the problems of great product quality fluctuation and heavy environmental pollution in the sulfur-containing silane in the production of sodium polysulfide from sodium sulfide and sulfur, and the problem of high cost in the sodium polysulfide prepared from sodium metal and sulfur at present in China. Since the temperature is low in the whole reaction process, no sulfur is volatilized, no sulfur dioxide (SO2) gas due to contact oxidation of air is generated, thus, the environmental pollution is slight, and the produced sulfur-containing silane product has stable sulfur distribution. The invention has the advantages of low cost, high control stability, stable product quality and light color.

Description

Technical field

[0001] The invention relates to a method for synthesizing a sulfur-containing silane coupling agent by using sodium polysulfide, and belongs to the technical field of organic chemistry. Background technique

[0002] Sulfur-containing silane is a conventional silane coupling agent, mainly used as an additive to tire rubber to improve the tire's tear resistance, wear resistance, wet grip and other properties. The most commonly used sulfur-containing silanes are bis-[3-(triethoxysilyl)propyl]-polysulfide, mainly bis-[3-(triethoxysilyl)propyl]-disulfide and Bis-[3-(triethoxysilyl)propyl]-tetrasulfide, the amount of which accounts for more than 90% of the total sulfur-containing silane. The synthesis method of its bis-[3-(triethoxysilyl)propyl]-polysulfide is mainly to use sodium polysulfide and 3-chloropropyltriethoxysilane to react to obtain the crude product, and then undergo a series of purification treatments Get its product. The quality level of sodium polysul...