Thermal Analysis of Plastics Used in the Food Industry

Fires in landfills, where used plastic packaging waste is discarded, have shown how great a fire hazard these types of materials pose. In this study, the course of thermo-oxidation of samples made of polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET) based plastics was determined. Based on an analysis of the dissociation energy of bonds between atoms in a polymer molecule, the mechanisms responsible for the character and course of degradation were observed. It was found that the degradation rate of PP and PS could be a result of the stability of C-H bonds on the tertiary carbon atom. In the case of PS, due to facilitated intramolecular hydrogen transfer, stabilization of hydroperoxide, and formation of a stable tertiary alcohol molecule, the onset of degradation is shifted towards higher temperatures than in the case of PP. Notably, the PP fragmentation occurs to a greater extent due to the easier course of β-scission. In addition, it was found that during a fire, the least amount of heat would be generated by thermo-oxidation of PS-based plastics. This is a result of the formation of a styrene molecule during decomposition that, due to the high stability of bonds in the aromatic ring, escapes from the combustion zone without oxidation. It has been proven that the greatest thermal effect accompanies PET decomposition, during which a phenyl radical is produced, where the C-H bonds break more easily in comparison with the bonds of an intact ring.

[1]  Hans-Josef Endres,et al.  Plastics in the context of the circular economy and sustainable plastics recycling: Comprehensive review on research development, standardization and market , 2021 .

[2]  G. Sevastyanov.  Adiabatic heating effect in elastic-plastic contraction / expansion of spherical cavity in isotropic incompressible material , 2021 .

[3]  G. Shamlan,et al.  Food packaging’s materials: A food safety perspective , 2021, Saudi journal of biological sciences.

[4]  C. Park,et al.  Efficient and selective sequestration of perfluorinated compounds and hexavalent chromium ions using a multifunctional spinel matrix decorated carbon backbone N-rich polymer and their mechanistic investigations , 2021 .

[5]  A. Brandyk,et al.  Respirable particles and polycyclic aromatic hydrocarbons at two Polish fire stations , 2020 .

[6]  M. Arjmand,et al.  Influence of polypropylene and nanoclay on thermal and thermo-oxidative degradation of poly(lactide acid): TG-FTIR, TG-DSC studies and kinetic analysis , 2020 .

[7]  G. Britovsek,et al.  Polyethylene terephthalate degradation under natural and accelerated weathering conditions , 2020 .

[8]  O. Olofinnade,et al.  Recycling of high impact polystyrene and low-density polyethylene plastic wastes in lightweight based concrete for sustainable construction , 2020 .

[9]  Shengqiang Yang,et al.  Restraining effect of nitrogen on coal oxidation in different stages: Non-isothermal TG-DSC and EPR research , 2020 .

[10]  Jiang-Tao Liu,et al.  Density functional theory study on bond dissociation energy of polystyrene trimer model compound , 2020, IOP Conference Series: Materials Science and Engineering.

[11]  M. Majder-Łopatka,et al.  The Influence of Hydrogen on the Indications of the Electrochemical Carbon Monoxide Sensors , 2019, Sustainability.

[12]  A. Bahramian,et al.  Nanostructure of Aerogels and Their Applications in Thermal Energy Insulation , 2019, ACS Applied Energy Materials.

[13]  H. White,et al.  PROTOCOL: Plastics in the food system: Human health, economic and environmental impacts. A scoping review , 2019, Campbell systematic reviews.

[14]  C. Spicker,et al.  The use of rheological behavior to monitor the processing and service life properties of recycled polypropylene , 2019, Food Packaging and Shelf Life.

[15]  Xiu-li Wang,et al.  Effect of biphenyl biimide structure on the thermal stability, flame retardancy and pyrolysis behavior of PET , 2018, Polymer Degradation and Stability.

[16]  B. Xie,et al.  Products derived from waste plastics (PC, HIPS, ABS, PP and PA6) via hydrothermal treatment: Characterization and potential applications. , 2018, Chemosphere.

[17]  Q. Jiao,et al.  Investigation on the thermal decomposition of hydroxyl terminated polyether based polyurethanes with inert and energetic plasticizers by DSC-TG-MS-FTIR , 2018, Journal of Analytical and Applied Pyrolysis.

[18]  D. Schiraldi,et al.  Comparison of Thermal Decomposition of Polystyrene Products vs. Bio-Based Polymer Aerogels , 2017 .

[19]  P. Soudant,et al.  Occurrence and effects of plastic additives on marine environments and organisms: A review. , 2017, Chemosphere.

[20]  Alexander Schindler,et al.  Identification of polymers by means of DSC, TG, STA and computer-assisted database search , 2017, Journal of Thermal Analysis and Calorimetry.

[21]  O. Frör,et al.  Plastic mulching in agriculture. Trading short-term agronomic benefits for long-term soil degradation? , 2016, The Science of the total environment.

[22]  R. Verma,et al.  Toxic Pollutants from Plastic Waste- A Review , 2016 .

[23]  John Lucas,et al.  A differential scanning calorimetric (DSC) study on the characteristics and behavior of water in low-rank coals , 2014 .

[24]  Hiroshi Ishii,et al.  Thermal oxidative degradation of additive-free polypropylene pellets investigated by multichannel Fourier-transform chemiluminescence spectroscopy , 2013 .

[25]  P. Whitmore,et al.  Measurement of peroxides in the volatile degradation products of polypropylene photooxidation , 2013 .

[26]  A. Ribes‐Greus,et al.  Thermal and thermo-oxidative stability of reprocessed poly(ethylene terephthalate) , 2013 .

[27]  Santiago Ferrándiz,et al.  Process behavior of compatible polymer blends , 2012 .

[28]  A Kashef,et al.  Survey Results of Combustible Contents and Floor Areas in Canadian Multi-Family Dwellings , 2011 .

[29]  Raf Dewil,et al.  Polymeric Cracking of Waste Polyethylene Terephthalate to Chemicals and Energy , 2011, Journal of the Air & Waste Management Association.

[30]  D. Bertin,et al.  Polypropylene degradation: Theoretical and experimental investigations , 2010 .

[31]  W. Nie,et al.  Effect of Copolymerization Time on the Microstructure and Properties of Polypropylene/Poly (ethylene- co -propylene) In-Reactor Alloys , 2009 .

[32]  S. Saengsuwan,et al.  Thermal decomposition kinetics of in situ reinforcing composite based on polypropylene and liquid crystalline polymer , 2009 .

[33]  E. Hinrichsen,et al.  Modification of mechanical properties of recycled polypropylene from post-consumer containers. , 2008, Waste management.

[34]  Pradip Paik,et al.  Kinetics of thermal degradation and estimation of lifetime for polypropylene particles: Effects of particle size , 2008 .

[35]  Xiaofeng Wang,et al.  Regulation of morphology and mechanical properties of polypropylene/poly(ethylene-co-propylene) in-reactor alloys by multi-stage sequential polymerization , 2007 .

[36]  S. H. Kim,et al.  Comparison of Pyrolysis Kinetics Between Rigid and Flexible Polyurethanes , 2007 .

[37]  Said Ahzi,et al.  Influence of temperature and strain rate on the mechanical behavior of three amorphous polymers: Characterization and modeling of the compressive yield stress , 2006 .

[38]  M. Kök.  Temperature-controlled combustion and kinetics of different rank coal samples , 2005 .

[39]  Linda J. Broadbelt,et al.  Tertiary Resource Recovery from Waste Polymers via Pyrolysis: Neat and Binary Mixture Reactions of Polypropylene and Polystyrene , 2001 .

[40]  Lin-Xian Feng,et al.  Structure and properties of polypropylene/poly(ethylene-co-propylene) in-situ blends synthesized by spherical Ziegler–Natta catalyst , 2001 .

[41]  Xinsheng Zhu.  Thermal and Thermo-Oxidative Degradation of Polystyrene with Ammonium Polyphosphate , 1996 .

[42]  J. Pospíšil.  Chemical and photochemical behaviour of phenolic antioxidants in polymer stabilization: A state of the art report, part II , 1993 .

[43]  V. Pacáková,et al.  A study of oxidative degradation of plastics by GC and GC-MS , 1985 .