Zinc Mercaptobenzothiazole, Accelerator, ZMBT, ZMBT-80, 155-04-4

ZINC MERCAPTOBENZOTHIAZOLE (ZMBT) 

CAS Number: 155-04-4
EC Number (EINECS): 205-840-3
Molecular Formula: C₁₄H₈N₂S₄Zn
Molecular Weight: 397.85 g/mol
REACH Status: Registered

SECTION 1: PRODUCT IDENTIFICATION AND CHEMICAL IDENTITY

SECTION 2: PHYSICAL AND CHEMICAL PROPERTIES

SECTION 3: SOLUBILITY PROFILE

Critical Note: ZMBT is insoluble in water but soluble in acetone and alkaline solutions. This solubility profile affects its incorporation into rubber formulations and its dispersion in latex systems.

SECTION 4: CHEMICAL PROPERTIES AND REACTIONS

4.1. Rubber Curing Mechanism

ZMBT is a secondary accelerator belonging to the benzothiazole class:

• Exhibits transition properties between MBT and MBTS

• Provides the longest scorch safety (processing safety)

• Curing speed is moderate

• Shows synergistic effect with MBTS/DPG system

• Provides lower crosslink density compared to MBT and MBTS

• In latex applications, provides higher modulus without extending curing time

4.2. Stability

SECTION 5: SPECTRAL DATA

SECTION 6: PURITY AND QUALITY SPECIFICATIONS

SECTION 7: MAJOR APPLICATIONS AND END-USES

7.1. Rubber Accelerator (Primary Application)

7.2. Corrosion Inhibitor

7.3. Dosage Levels

SECTION 8: COMPARATIVE PROPERTIES

8.1. Comparison of Thiazole Accelerators

SECTION 9: INDUSTRY SUITABILITY MATRIX

SECTION 10: PRODUCT VARIANTS AND COMMERCIAL FORMULATIONS

10.1. Commercial Forms

10.2. Trade Names

SECTION 11: OTHER NAMES AND SYNONYMS

SECTION 12: ADVANTAGES AND LIMITATIONS

12.1. Advantages

12.2. Limitations

SECTION 13: TOXICOLOGY AND HEALTH EFFECTS

SECTION 14: ECOTOXICOLOGY AND ENVIRONMENTAL BEHAVIOR

Ecotoxicological Summary: ZMBT shows low toxicity to aquatic organisms (LC₅₀ > 100 mg/L). Due to slow biodegradability, it may exhibit persistence in the environment. Classified as WGK 2 (hazardous to water). Release to the environment should be avoided.

SECTION 15: SAFETY MEASURES AND PERSONAL PROTECTIVE EQUIPMENT

SECTION 16: STORAGE INFORMATION

SECTION 17: TRANSPORT INFORMATION

SECTION 18: FIRE-FIGHTING MEASURES

SECTION 19: ACCIDENTAL RELEASE AND CLEANUP

SECTION 20: FIRST AID MEASURES

SECTION 21: REGULATORY INFORMATION

SECTION 22: SUMMARY AND CRITICAL WARNINGS

Basic Properties

CRITICAL WARNINGS

1. Superior Scorch Safety: ZMBT provides the longest scorch safety among thiazole accelerators. This is critical for processing safety in complex mold curing operations. Compared to MBT and MBTS, it offers a wider processing safety margin.

2. Secondary Accelerator: Exhibits transition properties between MBT and MBTS. Compared to MBTS/DPG system, it provides lower crosslink density; therefore, secondary accelerators (DPG, TMTD, etc.) should be used in applications requiring high crosslink density.

3. Latex Applications: When used with ZDMC/ZDEC in latex systems, it provides higher modulus without extending curing time. It does not affect latex stability and is preferred in latex foam production.

4. Non-Staining / Non-Discoloring: Can be safely used in colored and light-colored rubber products. Unlike MBT, it does not cause staining or discoloration in products.

5. Food Contact Approval: Regulated for food contact under FDA (21 CFR 177.2600, 175.105, 178.3120) and German BgVV. Can be used in rubber products that come into contact with food.

6. Low Toxicity: Has a lower toxicity profile compared to MBT and MBTS. Shows low acute toxicity with oral LD₅₀ > 2,000 mg/kg.

7. Nitrosamine Risk: Carries moderate nitrosamine risk. Careful evaluation is required in medical and sensitive applications. For low-nitrosamine formulations, alternative accelerators (TBzTD, ZBEC) should be considered.

8. Chemical Incompatibilities: Decomposes in strong acids and alkalies. Contact with these substances should be avoided.

9. Dusting and Inhalation Risk: Powder form may cause respiratory tract irritation and allergic skin reactions (H317). Proper dust control and personal protective equipment are mandatory.

10. Transport: Classified as UN 3077, Class 9, Packing Group III. Considered a marine pollutant.

11. Storage: Should be stored in cool, dry, well-ventilated areas. Protect from moisture, direct sunlight, and ignition sources.

12. Crosslink Density: Provides lower crosslink density compared to MBT and MBTS. Therefore, additional accelerator or sulfur adjustment may be required in applications requiring high hardness or modulus.

13. Curing Speed: Has moderate curing speed. In fast-curing systems, should be supported by secondary accelerators (DPG, TMTD, ZDC).

14. Masterbatch Use: ZMBT-80 (80% active masterbatch in rubber or EVA) provides lower dusting, better dispersion, and easier dosage compared to powder.

15. Sustainability: Due to nitrosamine risk, there is a trend toward transitioning to low-nitrosamine accelerators (TBzTD, ZBEC) for sustainable and safe rubber production.

IMPORTANT DISCLAIMER: This Technical Data Sheet (TDS) is for informational purposes only and is based on available scientific data. The user is solely responsible for determining the product's suitability for their specific application and for complying with all applicable local, national, and international regulations. For complete safety, storage, handling, transportation, disposal, and regulatory compliance information, always refer to the official Safety Data Sheet (SDS/MSDS) provided by the manufacturer/supplier. Users are responsible for testing the product in their own processes and applications. All local, national, and international regulations must be followed when working with ZMBT.