Biodegradable Plasticizer from Cardanol via Acid-Free Catalysis of Quaternary Ammonium Phosphotungstate

The most widely used phthalic ester plasticizers are reproductive toxic and nonbiodegradable. Developing biodegradable plasticizers from biomass resources remains a great challenge for the enrichment and pollution of plasticizers that seriously damage the environment. In this study, a biodegradable plasticizer (CEPT, cardanol-based epoxy plasticizer containing a triazine ring) was fabricated and derived from cardanol via acid-free catalysis. Subsequently, the essential performances, including mechanical properties, thermal degradation, thermal aging properties, solvent extraction resistance, and the microstructure of polyvinyl chloride plasticized with CEPT, were investigated. The mechanism behind these performances was explored. In addition, the biodegradability of CEPT was studied in active soil and in the Tenebrio molitor digestive system. The degradation products were obtained from the two research systems and characterized via Fourier-transform infrared spectroscopy, proton nuclear magnetic resonance, electrospray ionization mass spectrometry, and gas chromatography-mass spectrometry. The results illustrated that CEPT did undergo biodegradation and produced small-molecular components. The insect degradation method of biomass plasticizers proposed an original and available strategy for prevention of the pollution problem of plasticizers.

Automated summary

In this study, a biodegradable plasticizer called CEPT was synthesized from cardanol via acid-free catalysis. The polyvinyl chloride plasticized with CEPT exhibited good mechanical properties, thermal degradation, thermal aging properties, and solvent extraction resistance. It was found that CEPT underwent biodegradation and produced small-molecular components in active soil and in the Tenebrio molitor digestive system.