In the world of polymer science and industrial manufacturing, BIPB (Di(tert-butylperoxyisopropyl)benzene, CAS 2212-81-9) stands out as a game-changing crosslinking agent. Known commercially as “odorless DCP” or “crosslinking agent BIPB”, this organic peroxide has revolutionized rubber and plastic processing by eliminating the pungent byproducts traditionally associated with peroxides like DCP (Dicumyl Peroxide). With the European Chemicals Agency (ECHA) recently classifying DCP as a Substance of Very High Concern (SVHC), BIPB’s eco-friendly profile positions it as the sustainable successor in global polymer markets.
1. Chemical Profile & Key Properties
BIPB (C₂₀H₃₄O₄, MW: 338.48 g/mol) is a white to pale yellow crystalline solid. Its molecular structure features dual peroxide groups bonded to an isopropyl benzene backbone, enabling efficient free-radical generation during decomposition. Key properties include:
Melting Point: 44–48°C
Decomposition Kinetics:
10-hour half-life temperature: 117–121°C
1-minute half-life temperature: 169–185°C
Solubility: Insoluble in water; partially soluble in ethanol, ether, benzene, and CCl₄.
Active Oxygen Content: 9.45% (theoretical), ensuring high crosslinking efficiency.
Unlike conventional peroxides, BIPB decomposes into tert-butanol and acetone—volatiles with low odor thresholds—instead of malodorous acetophenone.
2. Applications: Versatility Across Industries
BIPB’s low-odor decomposition and high reactivity make it ideal for consumer-facing and precision applications:
2.1. Rubber & Elastomer Crosslinking
EPDM Seals/Automotive Parts: Enhances compression set resistance and thermal stability.
Silicone Medical Devices: Replaces DCP to avoid toxic residuals.
HNBR (Hydrogenated Nitrile Rubber): Used in oil-resistant gaskets and seals.
2.2. Foamed Plastics & Footwear
EVA Foam: Critical for midsole production in brands like Adidas, Nike, and Li-Ning due to uniform cell structure and minimal shrinkage.
PE Wire & Cable Insulation: Meets indoor air-quality standards (e.g., RoHS) for HVAC systems.
2.3. Specialty Polymers
TPEs (Thermoplastic Elastomers): Enables co-crosslinking of blends like EVA/EPDM and NBR/EPDM.
Degradable PP: Acts as a chain scission promoter.
3. Technical Advantages Over DCP
BIPB outperforms DCP in three critical areas:
Efficiency: Achieves equivalent crosslinking density at ~67% of DCP’s dosage, reducing material costs.
Odor & Toxicity: Eliminates volatile sulfur compounds and SVHC-listed residuals (DCP is now an SVHC under REACH).
Process Flexibility: Stable below 38°C and compatible with mixing, extrusion, and injection molding.
4. Safety & Handling Guidelines
As a UN 3106 (Class 5.2) hazardous material, BIPB requires careful handling:
Storage: Below 30°C in ventilated areas away from acids/reducing agents.
Thermal Risks: Self-accelerating decomposition begins at 80°C (SADT).
Certifications: Leading grades (e.g., Guangxi Donglan’s B13) comply with REACH, RoHS, and PAHs standards.
5. Market Outlook: The Shift to Sustainable Crosslinkers
With DCP’s SVHC classification in 2024, BIPB demand is projected to grow >15% annually. Manufacturers like Guangxi Donglan (China) now produce 5,000 MT/year of high-purity (>98%) BIPB, while suppliers offer three primary grades:
BIPB-96: Pure form (96% min) for high-performance applications.
BIPB-40A/40B: 40% masterbatches on CaCO₃ or silica carriers for safer dispersion.
6. Conclusion: Why BIPB is the Future of Polymer Modification
BIPB (CAS 2212-81-9) transcends being a mere DCP alternative. Its unparalleled combination of efficiency, low odor, and regulatory compliance addresses the polymer industry’s urgent need for sustainable chemistry. As R&D focuses on optimizing decomposition kinetics (e.g., Donglan’s 1,3-isomer B13 for faster curing), BIPB will continue displacing legacy peroxides in everything from EV batteries to biodegradable plastics.