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Versatile phosphite stabilizer that improves color, processing stability, and end-use of a variety of polymers.
WESTON™ 398 is a phosphite antioxidant that improves color and processing stability during recovery, drying, compounding, processing and end use. It has low nonylphenol content and synergizes when used along side hindered phenolic antioxidants.
Appearance: Clear liquid
Specific Gravity @ 25 °C: 0.980-0.992
Color (Pt - Co): 75 max
Flash Point (Closed Cup): 196 °C
Density @ 25 °C: 0.98 g/mL
Vapor Pressure @ 6 mm Hg: 245 °C
Molecular Weight: 688 g/mol
Viscosity @ 60 °C: 250 cps
Acid Number: 0.25 mg KOH/g
Refractive Index @ 25 °C: 1.5250-1.5280
Free Nonylphenol Content: ≤0.1
Phosphorus Content: 4.1-4.5%
Chlorine Content: < 25 ppm
Free Phenol Content: < 50 ppm
Specific Heat: 0.4 mcal/mg°C
Thermal Conductivity: 0.0003 gcal/sec(cm²)(°C/cm)
Auto-ignition Temperature: 439 °C
Primary Chemistry: Trisnonylphenyl Phosphite
Low color
Low nonylphenol content
Synergizes when used along side phenolic antioxidants
High concentration of nonylphenols in liquid phosphite antioxidants
Staining and coloring issues with the use of phosphite antioxidants
Compatibility and processability of phosphite antioxidants in HDPE and LLDPE applications
High density polyethylene, linear low density polyethylene
The SI Group portfolio of WESTON™ phosphite antioxidants protects plastics and elastomers from peroxide decomposers and offers excellent synergism with primary antioxidants, such as hindered phenols.
Compounders and recyclers face multiple challenges with the stabilization and processing of recycled plastics. Learn more and explore our solutions
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ChemPoint will not under any circumstances release personal user information to individuals or companies. All information collection is solely used to support ChemPoint customers service communications. Read our Privacy Notice.
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