Linear and cyclic oligomers in polybutylene terephthalate for food contact materials
- 28 December 2017
- journal article
- research article
- Published by Taylor & Francis Ltd in Food Additives & Contaminants: Part A
- Vol. 35 (3), 583-598
- https://doi.org/10.1080/19440049.2017.1414958
Abstract
Polybutylene terephthalate (PBT) is a polyester (PES) gaining more importance on the food contact material (FCM) market. However, little is known about the potential migration of PBT oligomers which are formed during polymer production. In this work, PBT pellets and a slotted spoon manufactured from this material by injection moulding were analysed on extractable oligomers and their migration potential into hydrophilic foods. Overall 27 oligomers (cycles and linears) could be identified in different extracts by HPLC-DAD/ESI-MS data, but without confirmation by reference substances. The oligomers were quantified by HPLC-DAD using bis(2-hydroxyethyl) terephthalate (BHET) as external standard and the total amount of oligomers isolated by reprecipitation from the pellets and the spoon were 0.69 and 0.71%, respectively. While cyclic oligomers made up for approximately 90% of the extractable oligomers, linear oligomers proved to be more relevant for migration into aqueous foodstuffs. Furthermore, it was shown that hydrolysis of oligomers can take place in water at elevated temperatures. Consequently, the qualitative and quantitative composition of PBT oligomers in aqueous foods from FCMs does not only depend on migration but also on hydrolysis. Migration testing of the PBT spoon under repeat use conditions with water at 100°C for 2 h resulted in 0.29 mg item−1 of linear oligomers and 0.05 mg item−1 of the cyclic PBT dimer in the third migrate.Keywords
This publication has 22 references indexed in Scilit:
- Qualitative and quantitative analysis of monomers in polyesters for food contact materialsFood Additives & Contaminants: Part A, 2016
- Migration of Cyclic Monomer and Oligomers from Polyamide 6 and 66 Food Contact Materials into Food and Food Simulants: Direct Food ContactPackaging Technology and Science, 2014
- Analysis of specific migration of monomers and oligomers from polyethylene terephthalate bottles and trays according to the testing methods as prescribed in the legislation of the EU and Asian countriesPolymer Testing, 2012
- Scientific Opinion on Exploring options for providing advice about possible human health risks based on the concept of Threshold of Toxicological Concern (TTC)EFSA Journal, 2012
- Scientific Opinion on the safety evaluation of the substance, cyclic oligomers of (butylene terephthalate), CAS No. 263244-54-8, for use in food contact materialsEFSA Journal, 2009
- Thermal stability of polyethylene terephthalate (PET): oligomer distribution and formation of volatilesPackaging Technology and Science, 1999
- Cyclic polyesters: 7. Preparation and characterization of cyclic oligomers from solution ring-chain reactions of poly(butylene terephthalate)Polymer, 1997
- Migration testing of plastics and microwave‐active materials for high‐temperature food‐use applicationsFood Additives & Contaminants, 1990
- High-performance liquid chromatographic determination of migrating poly(ethylene terephthalate) oligomers in corn oilJournal of Agricultural and Food Chemistry, 1990
- The structures and reversible polymerization of cyclic oligomers from poly(ethylene terephthalate)Journal of Polymer Science, 1960