Thermal and tensile behavior of LLDPE films containing limited amounts of an oxo-biodegradable additive and/or amorphous poly(1-hexene) before and after UV irradiation

Document Type: Original research

Authors

1 Department of Polymer Engineering, Shiraz Branch, Islamic Azad University, Shiraz, Iran, P.O. Box: 71993-3

2 Faculty of Engineering, Iran Polymer and Petrochemical Institute, Tehran, Iran, P.O. Box: 14975-112

10.22063/poj.2020.2611.1149

Abstract

Varying amounts of an amorphous poly(1-hexene) (PH, Mv 1.7×106 Da) were added to an LLDPE matrix containing 3% w/w Addiflex oxo-biodegradable additive (HES-W) and extruded and converted into films. Then the effect of presence of PH was investigated on microstructure, thermal and tensile behavior of polymer films before and after 6 weeks of ultra violet irradiation (UVR). Due to UVR, viscosity average molecular weight (Mv) of the sample without PH decreased from 9.6×104 to 4.6×103 Da and for the sample containing 3% w/w PH from 11.3×104 to 3.0×104 Da, also carbonyl index (CI) of the sample without PH increased from 0 to 28.7 while for the sample containing 3% w/w PH increased from 1.8 to 30.4. Moreover, differential scanning calorimetry (DSC) showed that crystallinity of the sample without PH increased from 34.4% to 36.9% and from 28.7% to 32.1% for the sample containing 3% w/w PH. Thermal gravimetric analysis (TGA) showed lower decomposition temperature for the samples containing PH. The elongation-at-break decreased from 723.0% to 88% for the sample without PH and from 410% to 10% for the sample containing PH. Atomic force microscopy (AFM) indicated smoother surfaces for samples containing 3% w/w PH before and after UVR. Although, the aforementioned results showed that the presence of limited amounts of PH in the LLDPE matrix deteriorated thermal and mechanical properties of the matrix, it hindered the oxo-biodegradablity of the matrix by opposing assimilation process perhaps due to high Mv and/or gelation.

Keywords

Main Subjects


  1. Weiland M, Daro A, David C (1995) Biodegradation of thermally oxidized polyethylene. Polym Degrad Stab 48: 275-89
  2. Albertsson A-C, Barenstedt C, Karlsson S, Lindberg T (1995) Degradation product pattern and morphology changes as means to differentiate abiotically and biotically aged degradable polyethylene. Polymer 36: 3075-83
  3. Jakubowicz I (2003) Evaluation of degradability of biodegradable polyethylene (PE). Polym Degrad Stab 80: 39-43
  4. Khajehpour-Tadavani S, Nejabat G-R, Mortazavi SMM (2018) Oxo-biodegradability of high-density polyethylene films containing limited amount of isotactic polypropylene. J Appl Polym Sci 135: 45843
  5. Khajehpour-Tadavani S, Nejabat G-R, Mortazavi SMM (2020) Changes in crystallinity of HDPE films containing different amounts of an oxo-biodegradable additive due to UVC exposure. Polyolefins J 7: 25-32
  6. Ammala A, Bateman S, Dean K, Petinakis E, Sangwan P, Wong S, Leong KH (2011) An overview of degradable and biodegradable polyolefins. Prog Polym Sci 36: 1015-49
  7. Linear Low-Density Polyethylene (LLDPE) Resins , https://ihsmarkit.com/products/linear-low-density-polyethylene-chemical-economics-handbook, Accessed 23 Feb 2020
  8. Ojeda TFM, Dalmolin E, Forte MMC, Jacques RJS, Bento FM, Camargo FAO (2009) Abiotic and biotic degradation of oxo-biodegradable polyethylenes. Polym Degrad Stab 94: 965-970
  9. da Luz JMR, Paes SA, Nunes MD, da Silva MCS, Kasuya MCM (2013) Degradation of oxo-biodegradable plastic by Pleurotus Ostreatus. PLOS ONE 8: e69386
  10. Koutny M, Sancelme M, Dabin C, Pichon N, Delort A, Lemaire J (2006) Acquired biodegradability of polyethylenes containing pro-oxidant additives. Polym Degrad Stab 91:1495–1503
  11. Ahmadjo S (2016) Preparation of ultra-high molecular weight amorphous poly(1-hexene) by a Ziegler–Natta catalyst. Polym Adv Technol 27: 1523-1529
  12. Nagle DJ, George GA, Rintoul L, Fredericks PM (2010) Use of micro-ATR/FTIR imaging to study heterogeneous polymer oxidation by direct solvent casting onto the ATR IRE. Vib Spectrosc 53: 24-27
  13. Kurata M, Tsunashima Y (1999) Viscosity-molecular weight relationships and unperturbed dimensions of linear chain molecules. In: Brandrup J, Immergut EH, Grulke EA, Editors. Polymer Handbook, New York, Wiley, pp. VII/10
  14. Ahmadjo S, Dehghani S, Zohuri G-H, Nejabat G-R, Jafarian H, Ahmadi M, Mortazavi SMM (2015) Thermal behavior of polyethylene reactor alloys polymerized by Ziegler–Natta/late transition metal hybrid catalyst. Macromol React Eng 9: 8-18
  15. Mohamed R, Mohd AF, Abdullah AFI (2011) Effect of aging on film strength and morphology of natural additive polypropylene packaging film. J Mater Sci Eng 5: 555-60
  16. Bernstein R, Thornberg SM, Assink RA, Mowery DM, Alam MK, Irwin AN, Hochrein JM, Derzon DK, Klamo SB, Clough RL (2007) Insights into oxidation mechanisms in gamma-irradiated polypropylene, utilizing selective isotopic labeling with analysis by GC/MS, NMR and FTIR. Nucl Instrum Methods Phys Res Sect B 265: 8-17

Volume 7, Issue 2
Summer and Autumn 2020
Pages 111-119
  • Receive Date: 29 November 2019
  • Revise Date: 10 March 2020
  • Accept Date: 10 March 2020