Effect of Thermal Aging on Migration Characteristics of Heavy Metal in PET

Abstract:

Polyethylene terephthalate (PET) is usually used as food packaging materials. And the heavy metal introduced during the process of manufacture usually exists in the spaces between macromolecules as monomer form. When PET contacts with real food, some heavy metals will migrate into the food since the motion of these molecules overcomes the binding power. As a result, it does great harm to our health. In this article PET was disposed in different thermal ageing conditions in order to accelerate its aging process. Then the original and aged PET samples were tested by Different Scanning Calorimeter (DSC) to characterize its crystallinity. And migration experiments was conducted on them using 4% acetic acid (V/V) as food simulate, the heavy metal content in food simulates was detected by Inductively Coupled Plasma Mass Spectrometry (ICP-MS), so that we can get the migration characteristics of heavy metal. The results show that different aging conditions can do harm to the structure of PET in varying degrees by changing its crystallinity and molecules arrangement. But the difference of crystallinity has no obvious effect on Sb migration characteristic of PET samples. While, the migration quantity of Sb increases significantly with the increase of migrate temperature. It will provide an important reference to the evaluation of use security and service life of PET in real usage to study the relation between heavy metal migration features and aging degree.

• Periodical: Materials Science Forum (Volume 850)
• Pages: 142-147
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.850.142
• Online since: March 2016
• Authors: Xiao Yun Song, Zhuo Jun Sun, Chun Ping Li, Jian Gao, Jing Long Ma, Bing Guo, Fu Wen Zhao, Hong Guan Yu, Jian Guo Gao
• Keywords: Crystallinity, Different Scanning Calorimeter, Heavy Metal Migration Quantity, Inductively Coupled Plasma Mass Spectrometry (ICP-MS), Polyethylene Terephthalate

References

[1] Demont M, Boutakhrit K, Fekete V, et al. Migration of 18 trace elements from ceramic food contact material: Influence of pigment, pH, nature of acid and temperature[J]. Food and Chemical Toxicology, 3-4(2012) 734-743.

DOI: 10.1016/j.fct.2011.12.043

[2] Lai S M, Liu J L, Huang C Y, et al. Preparation and Properties of Polyethylene Terephthalate (PET)/Near Infrared Reflective Pigment (NIR) Composites[J]. Journal of Macromolecular Science, Part B, 10(2013) 1355-1371.

DOI: 10.1080/00222348.2013.766075

[3] M H, A A, A B, et al. Migration of antimony from PET trays into food simulant and food: determination of Arrhenius parameters and comparison of predicted and measured migration data[J]. Food Additives & Contaminants: Part A, 3(2013) 587-598.

DOI: 10.1080/19440049.2012.751631

[4] Ruamcharoen P, Phetphaisit C W, Bumee R, et al. The Chemical Modification of Waste PET and its Application for a Wood-Polymer Composite Binder[J]. Advanced Materials Research, 488-489(2012) 648-653.

DOI: 10.4028/www.scientific.net/amr.488-489.648

[5] Rischpler C, Higuchi T, Nekolla S G. Current and Future Status of PET Myocardial Perfusion Tracers[J]. Current Cardiovascular Imaging Reports, 1(2015).

DOI: 10.1007/s12410-014-9303-z

[6] Tan C, Ahmad I, Heng M. Characterization of polyester composites from recycled polyethylene terephthalate reinforced with empty fruit bunch fibers[J]. Materials & Design, 8-9(2011) 4493-4501.

DOI: 10.1016/j.matdes.2011.03.037

[7] Mahdi F, Abbas H, Khan A A. Flexural, shear and bond strength of polymer concrete utilizing recycled resin obtained from post consumer PET bottles[J]. Construction and Building Materials, 44(2013) 798-811.

DOI: 10.1016/j.conbuildmat.2013.03.081

[8] Djebara M, Stoquert J P, Abdesselam M, et al. FTIR analysis of polyethylene terephthalate irradiated by MeV He+[J]. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 274(2012) 70-77.

DOI: 10.1016/j.nimb.2011.11.022

[9] Mohan T P, George A P, Kanny K. Combined Effect of Isophthalic Acid and Polyethylene Glycol in Polyethylene Terephthalate Polymer on Thermal, Mechanical, and Gas Transport Properties[J]. Journal of Applied Polymer Science, 2(2012) 536-543.

DOI: 10.1002/app.36818

[10] Liu S, Zhou L, Li L, et al. Isooctanol alcoholysis of waste polyethylene terephthalate in acidic ionic liquid[J]. Journal of Polymer Research, 12(2013).

DOI: 10.1007/s10965-013-0310-6

[11] The E C. Commission regulation (EU) No 10／2011on plastic materials and articles intended to come into contact with food: (2011).

[12] Takahashi Y, Sakuma K, Itai T, et al. Speciation of Antimony in PET Bottles Produced in Japan and China by X-ray Absorption Fine Structure Spectroscopy[J]. Environmental Science & Technology, 24(2008) 9045-9050.

DOI: 10.1021/es802073x

[13] Mahdi F, Abbas H, Khan A A. Strength characteristics of polymer mortar and concrete using different compositions of resins derived from post-consumer PET bottles[J]. Construction and Building Materials, 1(2012) 25-36.

DOI: 10.1016/j.conbuildmat.2009.08.006

[14] Colomines G, van der Lee A, Robin, et al. X-ray diffraction of the crystallinity of glycolysates derived from PET[J]. European Polymer Journal, 9(2008) 2874-2885.

DOI: 10.1016/j.eurpolymj.2008.07.008

[15] Mallick B. Analysis of strain-induced crystallinity in neutron-irradiated amorphous PET fiber [J]. Applied Physics A, 2(2015) 653-657.

DOI: 10.1007/s00339-015-9009-3

[16] Baseri S, Karimi M, Morshed M. Study of microstructure of oriented PET fibres exposed to supercritical carbon dioxide[J]. Fibers and Polymers, 1(2014) 161-168.

DOI: 10.1007/s12221-014-0161-8

[17] Kong Y, Hay J N. The measurement of the crystallinity of polymers by DSC [J]. Polymer, 43(2002) 3873-3878.

DOI: 10.1016/s0032-3861(02)00235-5

[18] Mohan T P, George A P, Kanny K. Determination of monomers and oligomers in polyethylene terephthalate trays and bottles for food use by using high performance liquid chromatography-electrospray ionization-mass spectrometry[J]. Polymer Testing, 3(2012).

DOI: 10.1016/j.polymertesting.2012.02.001

[19] Elżbieta S, Maria B, Frank V. Determination of chromium, cadmium and lead in food-packaging materials by axial inductively coupled plasma time-of-flight mass spectrometry[J]. Analytica Chimica Acta, 2(2003) 191-202.

DOI: 10.1016/s0003-2670(02)01527-1

[20] Qin Y, Zhang Z, Li L, et al. Inductively coupled plasma orthogonal acceleration time-of-flight mass spectrometry (ICP-oa-TOF-MS) analysis of heavy metal content in Indocalamus tesselatus samples[J]. Food Chemistry, 3(2013) 2154-2157.

DOI: 10.1016/j.foodchem.2013.04.103

[21] Xiaohong Y. Research of migrating behavior of harmful substance in food contact materials[D]. Zhejiang University, (2012).