Applications of Di-O-Tolythiourea in Industrial Manufacturing

As a direct manufacturer of Di-O-Tolythiourea, we supply this specialized compound to a select range of industrial sectors where its performance properties align with rigorous operational and regulatory standards. The following scenarios demonstrate how downstream manufacturers integrate our material within their process environments to deliver stable, high-quality finished products for international markets.

1. Rubber Curing Accelerator for Automotive and Industrial Tires

Major tire and technical rubber manufacturers use Di-O-Tolythiourea as a secondary accelerator in demanding sulfur vulcanization systems, where it enhances cure speed and crosslink density without compromising physical properties. Its controlled reactivity profile supports precision in batch and continuous processes, especially for high-performance radial and off-the-road tires requiring uniform mechanical properties and low cure reversion.

Industry compliance standards

• ISO 9001:2015 Quality Management Systems
• ISO 14001:2015 Environmental Management Systems
• REACH (EC 1907/2006) registration for rubber additives
• ASTM D3182, D2000 (Rubber Compound & Test Specifications)

Typical usage ratio

• 0.10–0.40 phr (parts per hundred rubber), finely adjusted per compound to balance cure kinetics and modulus targets, considering polymer type and processing method

Downstream process integration

• Dispersed into the masterbatch stage with other accelerators and sulfur during banbury mixing, followed by high-shear milling to ensure uniformity prior to extrusion or calendering

Final product types

• Passenger car radial tires
• Truck and bus tires
• Conveyor belts
• Industrial hoses and molded technical parts

2. Heat-Resistant Rubber Seals for Automotive and Industrial Gaskets

Producers of molded and injected seals specify Di-O-Tolythiourea in sulfur-cured EPDM, NBR, and HNBR rubber compounds to improve compression set and resistance to permanent deformation at elevated temperatures. This approach is essential for meeting automotive and mechanical sealing requirements in engine compartments, gearboxes, and aggressive fluid environments, where elastomer stability is critical for extended service intervals.

Industry compliance standards

• SAE J200 (Automotive Elastomer Standard)
• ISO 23936-2 (Elastomeric Seals for Oil & Gas)
• IATF 16949:2016 (Automotive Quality Management)
• RoHS Directive (2011/65/EU) for restricted substances

Typical usage ratio

• 0.15–0.35 phr, tailored to rubber type and target performance for high-heat environments, based on laboratory aging and dynamic testing results

Downstream process integration

• Incorporated during the initial mixing phase with primary and secondary accelerators, often alongside stearic acid and zinc oxide activators, followed by open mill refining for dispersion

Final product types

• Valve cover gaskets
• Oil pan seals
• Automotive O-rings and hydraulic seals
• High-temperature flange gaskets for industrial plants

3. Industrial Conveyor Belt Compound Formulation

Manufacturers of heavy-duty conveyor belts add Di-O-Tolythiourea to improve hot tear strength and maintain flexibility under prolonged stress and abrasion, particularly in mining, bulk materials handling, and logistics. Its use helps suppress cure reversion during long-duration vulcanization cycles typical of thick-gauge belt production and supports compliance with regulatory requirements for safety and mechanical integrity.

Industry compliance standards

• DIN 22102 (Conveyor Belts with Textile Carcass)
• MSHA Title 30 CFR Part 14 (Flame Resistance) for mining belts
• ISO 14890 (Conveyor Belts—Specification for Rubber or Plastics)
• GB/T 7984 (China National Standard—Rubber Conveyor Belts)

Typical usage ratio

• 0.10–0.30 phr, refined by batch based on cured thickness and target resistance to thermal aging and tear propagation

Downstream process integration

• Added to the compounding mixer alongside reinforcing fillers during masterbatch preparation, typically before final sulfur addition to control pre-curing

Final product types

• Underground mining conveyor belts
• Bulk cargo handling belts
• Inclined transport belts with heat resistance requirements

4. Anti-Scorch Compounding in Rubber Hose Production

Industrial hose factories use Di-O-Tolythiourea as a retarder/secondary accelerator to reduce premature scorch and extend safe processing time for complex extruded profiles and multi-layer hoses. This is crucial for long extrusion runs, reinforcement winding, and achieving proper adhesion between rubber layers, especially for oil-resistant and hydraulic hose lines subjected to stringent burst and longevity standards.

Industry compliance standards

• SAE J517 (Hydraulic Hose Standard)
• EN 853/854/857 (European Standards for Hydraulic Hoses)
• ISO 1402 (Rubber and Plastics—Hydraulic Hose Test Methods)
• UL 1660 (Safety for Liquid-Tight Flexible Nonmetallic Conduit)

Typical usage ratio

• 0.12–0.28 phr, carefully optimized based on in-process scorch time, targeted by laboratory Mooney viscosity and extrusion speed trials

Downstream process integration

• Introduced in the early mixing phase alongside polymer and filler loading, with active monitoring of scorch and rheometric properties before transition to extrusion or mandrel winding

Final product types

• Wire-reinforced hydraulic hoses
• Automotive coolant and fuel hoses
• Industrial multipurpose hoses for chemical and oil transfer

5. Specialty Rubber Rollers for Printing and Textile Machinery

Downstream producers of precision rubber rollers leverage Di-O-Tolythiourea in their compounding process to balance high abrasion resistance with resilience and long service intervals essential for modern high-speed printing presses, textile calenders, and laminators. Its inclusion addresses demands for stable mechanical properties under dynamic loading and repeated cleaning cycles, specifically where dimensional stability and aging resistance are mission-critical.

Industry compliance standards

• ISO 19447 (Rubber Rollers—Physical Properties)
• EN 12301 (Printing Machinery—Rollers—Requirements)
• ROHS 3 Directive (2015/863/EU)
• CQC-Marking (China Quality Certification for Equipment)

Typical usage ratio

• 0.14–0.25 phr, set by pilot compounding trials to achieve hardness, compression set, and surface finish retention

Downstream process integration

• Blended with elastomer base and reinforcing additives during initial mixing, followed by batch milling and precision extrusion/coating application onto pretreated roller mandrels

Final product types

• Offset and gravure printing press rollers
• Textile finishing and embossing rollers
• Film and sheet laminating rollers