Basic Information
- Name: CUROX® SOLAR SC
- Chemical Composition: 2,5-Dimethyl-2,5-di(tert-butylperoxy)hexane
- CAS Number: 78-63-7
- Form: Liquid, technically pure
- Molecular Weight: 290.4 g/mol
Description
- CUROX® SOLAR SC is a colorless, free-flowing liquid consisting primarily of technically pure 2,5-di(tert-butylperoxy)hexane.
- It is used as an initiator (radical source) for the cross-linking of polymers (especially EVA) and is widely used in photovoltaic applications.
Technical Data
- Appearance: Colorless liquid
- Purity: >93%
- Active oxygen content (calculated value): > 10.2% w/w
- No inhibitor
- Density (20°C): ~0.87 g/cm³
- Viscosity (20°C): ~7 mPa·s
- Refractive index (20°C): ~1.422
- Color Index (Hazen): ~50–80
- Insoluble in water, but miscible with alcohols and esters
- Vapor pressure (50°C/80°C/110°C): 8/27/95 mbar
- Critical temperature (SADT): ~90°C
- Refrigerated stability: Freezing point below 10°C
- Recommended storage temperature: 10°C to 40°C
- Storage stability (from date of delivery): 12 months
- Compliant with the European Waste Electrical and Electronic Equipment Directive (ElektroG) (EU Directives: RoHS 2002/95/EG, WEEE 2002/96/EG)
- Half-life: 10 hours/1 hour/1 minute (0.1 M/benzene): 120/142/190°C
Applications
- Used as a peroxide crosslinking agent for various polymers; particularly suitable for ethylene-vinyl acetate copolymer (EVA), polyethylene (LDPE, HDPE), ethylene-propylene-(diene) rubber (EPM, EPDM), silicone rubber (VMQ), and fluoroelastomers.
- Crosslinking temperature: Above 160°C; premature crosslinking does not occur below 130°C.
- Recommended usage: 0.5–3% w/w based on the material to be crosslinked. For certain inactive polymers, crosslinking efficiency can be improved by adding 0.5–1% w/w of a synergist (such as TAC or EDMA).
EVA Crosslinking
- CUROX® SOLAR SC can be premixed with EVA or added directly to a mixer or extruder suitable for thermoplastic materials.
- It is suitable for special encapsulation EVA grades with low softening temperatures (below 100°C) due to its sufficient thermal stability during the extrusion process.
- The final product (encapsulant sheet) exhibits long-term stability under ambient conditions, ensuring consistent compound quality over time.
- Vacuum lamination and crosslinking are typically performed at approximately 145°C; however, CUROX® SOLAR SC requires a higher crosslinking temperature, and it is recommended to use a crosslinking temperature above 160°C or to perform a second bake.
Measurement Data
- Table 1: Effect of peroxide dosage on torque (crosslinking rate) (viscoelastic plot at 180°C, EVA ELVAX® 1400Z (DuPont))
- Table 2: Effect of Temperature on Crosslinking Rate [minutes] (Viscoelastic plot, EVA ELVAX® 1400Z (DuPont))
Standard Packaging
- 25 kg (55.12 lb) polyethylene drum
Disclaimer
- The information and technical recommendations provided are based on internal testing and local raw materials and are intended solely to provide information about the product and its applications. They do not constitute a guarantee of the product’s properties or suitability, nor do they constitute complete instructions for use.
- This information does not constitute a guarantee of product performance or shelf life, nor does it assume any responsibility or liability regarding intellectual property rights, particularly patent rights.
- We reserve the right to make any changes based on technical progress or further development.
- The use and application of the product in accordance with our technical recommendations is beyond our control; it is the user’s responsibility to carefully inspect the goods upon receipt to verify their suitability.