Method for preparing insoluble sulfur

Abstract

The present invention discloses a method for preparing insoluble sulfur, and the method comprises the following steps of: adding sulfur into a reactor, when the temperature in the reactor rises to 160 degrees centigrade, starting stirring, and adding a stabilizer after keeping the temperature for 10-15min; continuing to heat to a reaction temperature, actuating a fan after the reaction is terminated, simultaneously feeding nitrogen gas into the reactor, and rapidly cooling the reaction product which enters an ice water bath from sieve pores; placing the cooled product into an drying oven for curing and drying, then ball milling for crushing, adding the crushed product together with an extractant into an extraction tank to perform extraction, for residue after suction filtration, repeatedly performing the above-mentioned extraction and filtration until the final residue is substantially constant in weight, and vacuum drying the residue to obtain insoluble sulfur powder. The insoluble sulfur obtained by using the present method is not mixed with metal ions; the improvement of the reactor apparatus can accelerate the cooling of the product; and the organic solvent used is non-toxic and non-volatile.

Description

technical field

[0001] The invention relates to the preparation of vulcanizing agent insoluble sulfur used in tire rubber, in particular to a method for preparing insoluble sulfur by melting at low temperature. Background technique

[0002] Insoluble sulfur, also known as μ-type sulfur. The product is a light yellow powder with an amorphous structure, insoluble in organic solvents such as carbon disulfide and toluene, and is a non-toxic polymer modified by special processing and polymerization of ordinary sulfur with an eight-membered ring structure that is soluble in carbon disulfide Variety. Insoluble sulfur is chemically inert and physically inert. It has good distribution stability in the rubber compound, uniform vulcanization and cross-linking points of the product, overcomes the "blooming" phenomenon on the surface of the rubber compound, and can prevent early scorching of the rubber compound during processing. It can be widely used in tire carcass rubber, buffer rub...