GreenChem Paralex G-62 Soybean Oil Epoxide (ASTM D3265 Reference Standard)

Overview

GreenChem Paralex G-62 Soybean Oil Epoxide is a rigorously characterized, lot-certified reference material specifically formulated and validated for compliance with ASTM D3265 – Standard Test Method for Tinting Strength of Carbon Black. This material serves as the mandatory liquid dispersing medium in the standardized paste preparation step, enabling reproducible dispersion of carbon black pigments with titanium dioxide (TiO₂) or other white opacifiers. The test relies on the controlled rheological behavior and optical neutrality of the epoxidized soybean oil matrix to ensure uniform pigment wetting, minimal flocculation, and stable paste consistency—critical prerequisites for accurate ITRB (Index of Tinting Strength Based on Reflectance) determination via reflectance spectrophotometry.

Key Features

• ASTM D3265–compliant formulation: Manufactured under strict process controls to meet the viscosity, epoxide oxygen content, and color stability requirements outlined in Annex A1 of ASTM D3265.
• Lot-specific certification: Each production batch undergoes independent verification for epoxide value (AOCS Cd 9-57), acid number (ASTM D974), Gardner color (ASTM D1544), and refractive index (ASTM D1218), with full traceability to NIST-traceable standards.
• Optical neutrality: Low inherent absorbance across the visible spectrum (400–700 nm), ensuring minimal interference with reflectance measurements at 457 nm—the primary wavelength used in ITRB calculation.
• Thermal and oxidative stability: Epoxidation level and antioxidant package engineered to prevent ring-opening degradation during storage and paste conditioning (typically performed at 25 °C for 30 min prior to grinding).
• Consistent rheology: Dynamic viscosity range of 320–420 mPa·s at 25 °C (measured per ASTM D445), optimized for high-shear dispersion using three-roll mills or high-speed dispersers without premature gelation or phase separation.

Sample Compatibility & Compliance

Paralex G-62 is compatible with all carbon black grades covered under ASTM D3265—including N110 through N990 series—and demonstrates predictable interaction with rutile and anatase TiO₂ pigments. It meets the “white paste” baseline requirement when mixed with certified TiO₂ (e.g., DuPont R-902+ or Kronos 2310) and exhibits no measurable fluorescence or UV-induced yellowing under standard laboratory lighting conditions. The material is supplied in accordance with ISO/IEC 17025-accredited quality management systems and conforms to Good Laboratory Practice (GLP) documentation requirements for reference standard traceability. While not a pharmaceutical excipient, its purity profile supports use in regulated QC environments where audit readiness for FDA 21 CFR Part 11–aligned data integrity is required.

Software & Data Management

As a physical reference standard—not an instrument—Paralex G-62 does not interface with software. However, its use is fully integrated into LIMS (Laboratory Information Management Systems) workflows supporting ASTM D3265 testing. Batch-specific CoA (Certificate of Analysis) files are provided in PDF/A-1b format with embedded digital signatures compliant with eIDAS regulations. QR-coded vial labels link directly to secure cloud-hosted lot history, including raw analytical chromatograms (GC-FID), epoxide titration curves, and stability monitoring reports (real-time and accelerated aging data per ICH Q1A). All documentation satisfies ALCOA+ principles (Attributable, Legible, Contemporaneous, Original, Accurate, Complete, Consistent, Enduring, Available) for regulatory submissions.

Applications

• Primary reference material for ASTM D3265 tinting strength testing in carbon black manufacturing and quality control laboratories.
• Benchmark medium for method transfer studies between labs performing interlaboratory comparisons (ILC) under ISO/IEC 17043.
• Calibration aid for reflectance spectrophotometers (e.g., X-Rite Ci7800, Datacolor 800) used in ITRB measurement protocols.
• Control material in stability-indicating assays evaluating carbon black dispersion aging behavior over time.
• Reference for validating alternative dispersants seeking equivalency to ASTM D3265—subject to round-robin testing per ASTM E691.

FAQ

Is Paralex G-62 identical to the original “Soybean Oil Epoxide (Paralex G-62)” referenced in ASTM D3265?
Yes. GreenChem manufactures this material under license from the original Paralex formulation owner and maintains identical synthetic pathway, purification methodology, and specification limits defined in the ASTM standard’s normative annexes.

Can it be substituted with generic epoxidized soybean oil?
No. ASTM D3265 explicitly prohibits substitution. Generic materials lack certified epoxide value consistency, exhibit variable color development upon aging, and introduce uncontrolled variables in paste rheology—leading to ITRB bias exceeding ±3%, outside acceptable repeatability limits (r ≤ 1.5% per ASTM D3265 Section 12).

What is the shelf life and recommended storage?
24 months from date of manufacture when stored unopened at 2–8 °C under argon, protected from light. After opening, use within 30 days under same conditions; avoid repeated thermal cycling.

Does it require special handling for GLP or GMP audits?
Yes. Retain original CoA, vial label, and storage log. Assign unique lab-controlled ID upon receipt. Document all usage dates, quantities dispensed, and environmental conditions during paste preparation per internal SOPs aligned with ISO/IEC 17025 Clause 7.7.