Mechanism of acetaldehyde formation in polyethylene terephthalate resin—A new insight

Abstract

Acetaldehyde is one of the well‐known undesirable by‐product formed during different stages of polyethylene terephthalate manufacturing process. The migration of acetaldehyde from polyethylene terephthalate, even at trace levels of 10–25 ppb is known to adversely impact organoleptic property of water and/or beverages. We are reporting for the first time in‐situ formation of acetaldehyde in polyethylene terephthalate pellets due to the presence of residual levels of 2‐methyl 1, 3‐dioxolane in the final polymer. A new insight on generation of acetaldehyde through hydrolysis of 2‐methyl 1, 3‐dioxolane present in polyethylene terephthalate resin has been established through water spiking studies in a controlled environment. Further, systematic studies were conducted to also understand the mechanism of formation of 2‐methyl 1, 3‐dioxolane during the polyethylene terephthalate manufacturing.

Poly(alkylene terephthalate)s: From current developments in synthetic strategies towards applications

“…Both FA and AA can leach out from PET and the latter gives rise to an undesirable taste or odour to the content of the package. [149,150] There are multiple ways in which FA and AA can be generated in PET including via thermal degradation during the solid state polymerisation or injection moulding and through byproduct formation during melt polycondensation of PET. [151] Villain et al reported on the degradation of PET and showed that a mass loss of 0.5 % was reached after exposing a sample to 300 °C for approximately 20 minutes in an inert atmosphere.…”