𝗡𝗲𝘄 𝗿𝗲𝘀𝗲𝗮𝗿𝗰𝗵 💡 𝗨𝗻𝗱𝗲𝗿𝘀𝘁𝗮𝗻𝗱𝗶𝗻𝗴 𝗮𝗻𝘁𝗶𝗼𝘅𝗶𝗱𝗮𝗻𝘁 𝗯𝗲𝗵𝗮𝘃𝗶𝗼𝗿 𝗶𝗻 𝗿𝗲𝗰𝘆𝗰𝗹𝗲𝗱 𝗽𝗼𝗹𝘆𝗽𝗿𝗼𝗽𝘆𝗹𝗲𝗻𝗲
What happens to antioxidants when polypropylene (PP) is recycled? And how can we accurately and affordably track them?
In their latest study, Niek Knoben, Max Vanhouttem, Aike Wypkema, and Nithya Subramanian from Brightlands Materials Center demonstrate a practical method to monitor antioxidant (AO) levels during mechanical recycling — both in open- and closed-loop systems.
They adapted a known technique (Oxidation Induction Temperature, or OIT) using Differential Scanning Calorimetry (DSC) in sealed pans under inert atmosphere. This avoids interference from volatile compounds and allows for safer, cleaner, and more representative measurements — particularly important in recycled plastics that may contain unknown contaminants.
Their findings show a strong correlation between the OIT and actual AO content at different recycling stages, offering recyclers a simple yet powerful tool to assess the state of stabilization in recycled PP. This not only helps in avoiding unnecessary AO build-up, but also in maintaining product performance and safety.
This work paves the way for smarter, safer additive strategies — a big step forward for circular polypropylene use. Read the full paper below 👇