How Entropy Calculates Biobased Content Figures
All biobased content data for Entropy products are reported according to ASTM D6866. This standard is recognized by governments and companies world-wide as a valid tool for quantifying the renewable carbon content of biobased products.
Entropy Resins uses two metrics for reporting biobased content:
1) ASTM D6866 for measuring biobased CARBON content (C atoms only)
2) A calculated total biobased content by MASS (includes bio-based C,O, and N atoms)
ASTM D6866 is the standard used for testing and reporting bio-content by the USDA BioPreferredSM Program. Because the test can only measure biobased carbon atoms, the USDA can only certify that portion of the total biomass. This reading is the number we report as part of our USDA certified biobased content.
Our polymers are hybrid molecules that contain both bio-based and petroleum based parts. However, since we know the structure of the bio-based pre-polymers and the chemistry involved during polymerization, we can therefore calculate the total biomass (carbon, nitrogen, and oxygen) in the polymeric chain based on the ASTM D6866 reading alone, i.e. we know which nitrogens and oxygens that accompany the bio-based carbons during polymerization. The total atomic weight of all bioderived atoms is then divided by the molecular weight of the polymeric subunit to get a total biobased content by mass.
Entropy Resins reports the total bio-content by mass as a semi-empirical number, using partial experimental data (ASTM D6866) and basic scientific laws. Please refer to our products' Technical Data Sheets for their exact biobased content.
For more information about ASTM D6866: http://www.astm.org/Standards/D6866.htm