Biodegradable polymers are an important part of the solution toolbox to achieve circularity in the plastic economy and overcome negative impacts of a linear plastic economy. Biodegradable polymers need to excel not only on a mechanical performance level in the application to fulfill their function during the use phase but also on a biodegradation performance level after use. The biodegradation performance is tailored to the application and the receiving environment of the polymer product after use, which can be both engineered systems (e.g., compost, anaerobic digestors, wastewater treatment plants) and natural systems (e.g., soils, freshwater, or marine environments). This chapter addresses key aspects of polymer biodegradability and biodegradation in both natural and engineered systems with the goal to advance a more holistic view on the topic and, thereby, provide guidance for all stakeholders working on developing, testing, and regulating biodegradable polymers. These aspects include definitions of biodegradability and biodegradation, elucidating polymer- and environmental factors that control the biodegradation process, a discussion of the analytical chemistry of polymer biodegradation, polymer biodegradability testing and certification, as well as a brief overview of research needs. In accordance with the diverse backgrounds of the authors of the chapter, this chapter targets all stakeholder groups from academics to industry and regulators.

In the present work, a procedure based on a dispersive medium for carbon black (CB) isolation from soil samples for analysis was proposed for the first time. Polymeric and biological dispersants and a sequential use of both dispersants were assayed. Asymmetrical flow field flow fractionation with dynamic light scattering detector (AF4-DLS) and sedimentation field flow fractionation with multi-angle light scattering detector (SdF3-MALS) were used for CB quantitation and characterization in the achieved dispersions. Soil samples contaminated with CB were processed, and CB isolation depended on the solid size distribution and composition and dispersant nature. More quantitative isolations were achieved for the four soils treated by the biological dispersant. As the organic matter percentage is higher in soil, the CB isolation was better, varying between 75 and 99% with standard deviation (s) ⩽ 2% for all soils. A soil contaminated with a CB-based pigment paste was analyzed, achieving (99 ± 2)% expressed as expanded uncertainty (K = 2) of dispersive isolation by the biological dispersant, and the sampling was scaled to 250 g of soil with positive results. The procedure was completed by CB recovery to obtain a solid residue able to be reused if necessary. For the filter-aided recovery step, different membranes (fiberglass, nylon, and Teflon) with a pore size between 0.1 and 5 μm were tested. The quantitation of the CB retained in the filter was measured by diffuse reflectance spectroscopy. Teflon (0.10 μm) provided better results for CB recovery, and its re-dispersion was also studied with suitable results. Determination of CB from the filters by diffuse reflectance spectrometry provided the same results than AF4 for CB dispersions.