Abstract
Evaluation of biobased content of biobased polymers and their composites by measuring carbon-14 using accelerator mass spectrometry (AMS) was described. Biobased carbon content can be evaluated by measuring
carbon-14 content using AMS, since biomass includes carbon-14 atoms in atoms of its constitution and fossil include no carbon-14 atoms in it. Sample preparation and pretreatment for AMS were explained in detail. Results of
biobased content of plants, polymers and polymer composites by AMS were shown. Reproducibility and accuracy of
AMS measurement were investigated. Evaluation method for biobased polymer content of polymer products can be
also obtained using results by AMS. Examples of these evaluation results were shown. The international standards
concerning this method were also described.