Chemical synonyms:

   Insoluble Sulfur, Polymeric sulfur

Product description

CAS No. Polymeric sulfur: 9035-99-8 Process oil: 64742-52-5

Crystex™ Cure Pro is a non-blooming vulcanizing agent for unsaturated elastomers that offers tire manufactures improved productivity and reliability of supply without compromising safety. Crystex Cure Pro offers an unmatched combination of premium thermal stability, in-rubber dispersion and flowability. Crystex Cure Pro is oiled to 10.5 % but maintains the high standard of dust safety exhibited by existing Crystex products.


Crystex Cure Pro is polymeric sulfur and is insoluble in elastomers. Consequently, it will retard bin scorch, prevent migration of sulfur and preserve surface tack.

Crystex Cure Pro is used in compounds containing a relatively large sulfur loading above the solubility of sulfur in the elastomer and compounds that require higher processing temperatures or additional bloom protection.

Crystex Cure Pro offers less hassle during material handling, less tendency for product to compact, and improved accuracy in automatic dosing systems due to its significantly improved flow characteristics.

At vulcanization temperatures Crystex Cure Pro will de-polymerize to soluble sulfur and will behave similarly to Rubber Maker's sulfur.

Reversion of Crystex Cure Pro to soluble sulfur is also catalyzed by alkaline products. The presence of alkaline accelerators can be critical.

Crystex Cure Pro is non-staining and non-discoloring.


  • Rubber modification
  • Tires
  • Tires-custom

    Regulatory information and data sheets

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