Meaning
Analytical testing of the carbon isotope ratio provides a physical method for determining the bio-based content in polymer samples. This radiocarbon c14 analysis distinguishes between modern carbon from renewable sources and ancient carbon found in fossil fuels. The method follows ASTM D6866 standards to quantify the percentage of biological material present in a resin.
Scientific Basis
Living organisms maintain a constant ratio of the radioactive carbon-14 isotope which begins to decay at a known rate once the organism dies. Since fossil fuels are millions of years old, they contain no measurable carbon-14, making radiocarbon c14 analysis a precise tool for detecting adulteration. The presence of the isotope confirms the renewable origin of the feedstock.
Industrial Validation
Manufacturers use this test to verify the claims made by suppliers of bio-polymers or bio-composites. While mass balance accounting relies on bookkeeping, radiocarbon c14 analysis offers an empirical check on the final part. It is the gold standard for verifying renewable content in the absence of a tracked supply chain.
Application Limits
This technique cannot identify the presence of chemically recycled plastic because both recycled and virgin plastics are derived from fossil sources. For those materials, radiocarbon c14 analysis will return a result of zero percent bio-based content. It is strictly a tool for biological feedstock verification.
