Introduction
Tert-Butyl peroxy-2-ethylhexanoate (TBPEH), CAS 3006-82-4, is a widely used peroxyester initiator that has earned its place as a cornerstone of the PVC and acrylic polymer industries. Its reactivity profile, characterized by a moderately low decomposition temperature, makes it ideally suited for suspension and mass polymerization processes conducted in the 50-80 deg C range.
Key Facts: TBPEH
- CAS Number: 3006-82-4
- Molecular Formula: C12H24O3
- Molecular Weight: 216.32 g/mol
- Appearance: Colorless to pale yellow liquid
- Density: ~0.90 g/cm3 at 20 deg C
- 10-Hour Half-Life Temperature: ~73 deg C
- 1-Hour Half-Life Temperature: ~92 deg C
- SADT: ~45 deg C
- UN Classification: UN 3113 (Organic Peroxide Type D, liquid, temperature controlled)
Physical and Chemical Properties
| Property | Value |
|---|---|
| Appearance | Colorless to pale yellow liquid |
| Purity (Typical) | 95-98% |
| Active Oxygen | ~7.4% (theoretical) |
| Density (20 deg C) | 0.90 g/cm3 |
| Viscosity (20 deg C) | ~3 mPa.s |
| Solubility in Water | Insoluble |
| Solubility in Monomers | Excellent in styrene, MMA, VCM, acrylates |
Key Applications
1. PVC Suspension Polymerization
TBPEH is one of the most important initiators for suspension PVC (S-PVC) production. Its decomposition rate in the 55-65 deg C range is well-matched to industrial PVC reactor conditions, providing controlled radical generation throughout the polymerization cycle. TBPEH-initiated PVC exhibits excellent particle morphology, porosity, and thermal stability.
2. Polystyrene Production
In general-purpose polystyrene (GPPS) and high-impact polystyrene (HIPS) manufacturing, TBPEH serves as a medium-temperature initiator. It is particularly valued in continuous mass polymerization processes where predictable radical flux is essential for maintaining steady-state operation and product consistency.
3. Acrylic Polymerization
TBPEH effectively initiates the polymerization of methyl methacrylate, butyl acrylate, and other acrylic monomers in both bulk and solution processes. Its decomposition products are relatively benign, resulting in minimal impact on polymer color and clarity.
Safety and Handling
Due to its SADT of approximately 45 deg C, TBPEH requires temperature-controlled storage and transport. Critical safety measures include:
- Refrigerated storage at temperatures below 10 deg C (or as specified by manufacturer)
- Continuous temperature monitoring during storage and transport
- Use of explosion-proof equipment in handling areas
- Strict avoidance of contamination with strong acids, bases, and accelerators
- Emergency response planning including spill containment and fire suppression
Frequently Asked Questions
Q: Why is TBPEH preferred over other peroxyesters for PVC production?
A: TBPEH offers an optimal combination of decomposition temperature, solubility in VCM, and cost-effectiveness for PVC suspension polymerization. Its half-life at typical S-PVC temperatures (55-65 deg C) provides efficient initiation without excessive residual peroxide at the end of the polymerization cycle. Additionally, TBPEH contributes to good particle morphology control, which is critical for PVC resin quality.
Q: What are the storage requirements for TBPEH?
A: TBPEH must be stored under refrigeration, typically at temperatures below 10 deg C (the exact maximum storage temperature depends on the specific formulation and concentration). Storage areas must be equipped with temperature monitoring and alarm systems, explosion-proof electrical equipment, adequate ventilation, and secondary containment. TBPEH should never be stored near heat sources, incompatible materials, or in unmonitored areas.
Key Takeaways
- TBPEH (CAS 3006-82-4) is a medium-temperature peroxyester initiator essential for PVC suspension polymerization.
- Its 10-hour half-life of ~73 deg C and 1-hour half-life of ~92 deg C provide excellent reactivity in the 55-80 deg C range.
- Primary applications include S-PVC, polystyrene, and acrylic polymer production.
- Due to its SADT of ~45 deg C, TBPEH requires refrigerated storage and temperature-controlled transport.
- Shandong Do Sender Chemicals supplies high-quality TBPEH for demanding industrial polymerization processes.