Introduction
Diisopropyl peroxydicarbonate (IPP), CAS 105-64-6, is one of the most reactive commercially available peroxydicarbonates. With a 10-hour half-life temperature of approximately 40 deg C, IPP is valued for its ability to provide rapid radical generation at very low polymerization temperatures, enabling the production of specialty PVC grades with exceptionally high molecular weight.
Key Facts: IPP
- CAS Number: 105-64-6
- Molecular Formula: C8H14O6
- Molecular Weight: 206.19 g/mol
- Appearance: Colorless to pale yellow liquid or solid (temperature-dependent)
- Active Oxygen: ~7.8% (theoretical)
- 10-Hour Half-Life Temperature: ~40 deg C
- SADT: ~0 to 5 deg C
- Storage: Deep refrigerated, typically -20 to -25 deg C
Physical Properties
| Property | Value |
|---|---|
| Appearance | Colorless liquid (liquid) or white solid (solid, below ~8-12 deg C) |
| Molecular Weight | 206.19 g/mol |
| Active Oxygen | 7.8% (theoretical) |
| Solubility in VCM | Excellent |
| SADT | ~0-5 deg C |
Applications
High K-Value PVC
IPP’s extremely low decomposition temperature makes it the initiator of choice for producing PVC grades with K-values above 70. Low-temperature polymerization favors chain propagation over chain transfer and termination, yielding higher molecular weight polymer. These high K-value PVC grades are essential for applications requiring maximum mechanical strength and durability, including pressure pipes, window profiles, and industrial sheet.
Specialty Copolymers
IPP is also employed in the production of specialty vinyl copolymers and graft copolymers where low-temperature initiation provides advantages in controlling copolymer composition and molecular architecture.
Safety and Storage
IPP’s exceptionally low SADT of 0-5 deg C demands the most stringent cold chain management in the organic peroxide industry:
- Storage at -20 to -25 deg C in explosion-proof deep-freeze facilities
- Transport in specialized refrigerated containers with redundant cooling and real-time temperature monitoring
- Maximum transport/storage duration strictly controlled
- All handling equipment must be explosion-proof and grounded
Q: Why does IPP require such extreme cold storage?
A: IPP’s SADT of approximately 0-5 deg C means that self-accelerating decomposition can begin at temperatures only slightly above freezing. Storage at -20 to -25 deg C provides a substantial safety margin (approximately 25 deg C below SADT), ensuring that the decomposition rate remains negligible throughout the storage period. Even brief temperature excursions above the recommended maximum can initiate decomposition that may not be immediately apparent but can compromise product quality and, critically, safety.
Q: What are the alternatives to IPP for low-temperature PVC initiation?
A: While IPP is the most reactive common peroxydicarbonate, alternatives include di-sec-butyl peroxydicarbonate (SBP, T10h ~42 deg C) and di-n-propyl peroxydicarbonate (NPP, T10h ~41 deg C). Initiator selection involves balancing reactivity, availability, cost, and storage requirements for the specific application.
Key Takeaways
- IPP (CAS 105-64-6) is the most reactive common peroxydicarbonate with a T10h of ~40 deg C.
- It is essential for producing high K-value PVC grades with exceptional mechanical properties.
- Its SADT of 0-5 deg C demands storage at -20 to -25 deg C with rigorous cold chain management.
- Shandong Do Sender Chemicals supplies IPP with industry-leading cold chain logistics and safety management.