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Change of Crystalline Properties of Poly(ethylene-co-vinyl acetate) according to the Microstructures

  • Received : 2021.06.16
  • Accepted : 2021.06.30
  • Published : 2021.06.30

Abstract

Microstructure-dependent changes in the crystalline properties of poly(ethylene-co-vinyl acetate) (EVA) was investigated using various EVAs at different VA contents via X-ray diffraction (XRD). The parameters analyzed herein were percentage crystallinity (Xc), interplanar crystal spacing (dhkl), crystal stack size (Dhkl), and the number of crystal plane piles (Nhkl). The Xcs of [110] and [200] crystals were 21.0-4.1 and 6.7-1.4%, respectively, and they decreased by approximately 2.3 and 0.7% for every mol% of the VA content, respectively. The Xc ratios of the [110] and [200] crystals were approximately 3. The d110s and d200s values were 0.41-0.42 and 0.37-0.38 nm, respectively. The D110s and D200s values were 9.56 -21.92 and 7.00-16.42 nm, respectively. The dhkls increased with an increase in the VA content, whereas the Dhkls decreased. The N110s and N200s were 22.7-51.3 and 18.3-43.2, respectively, and they decreased by increasing the VA content. EVA with the same VA content showed different crystalline properties as per the suppliers, and some EVAs deviated from the average trends. This could be explained by the difference in their microstructures such as the sizes and distribution uniformity of the ethylene sequences in EVA chains.

Keywords

References

  1. S. Bistac, P. Kunemann, and J. Schultz, "Crystalline modifications of ethylene-vinyl acetate copolymers induced by a tensile drawing: effect of the molecular weight", Polymer, 39, 4875 (1998). https://doi.org/10.1016/S0032-3861(97)10328-7
  2. S. Bistac and J. Schultz, "Influence of tensile deformation on the crystalline organization of ethylene copolymers", J. Macromol. Sci. B Phys., 38, 663 (1999). https://doi.org/10.1080/00222349908248129
  3. X. M. Shi, J. Zhang, J. Jin, and S. J. Chen, "Non-isothermal crystallization and melting of ethylene-vinyl acetate copolymers with different vinyl acetate contents", Exp. Polym. Lett., 2, 623 (2008). https://doi.org/10.3144/expresspolymlett.2008.75
  4. M. Alexandre, G. Beyer, C. Henrist, R. Cloots, A. Rulmont, R. Jerome, and P. Dubois, "Preparation and properties of layered silicate nanocomposites based on ethylene vinyl acetate copolymers", Macromol. Rapid Commun., 22, 643 (2001). https://doi.org/10.1002/1521-3927(20010501)22:8<643::AID-MARC643>3.0.CO;2-#
  5. W. Zhang, D. Chen, Q. Zhao, and Y. Fang, "Effects of different kinds of clay and different vinyl acetate content on the morphology and properties of EVA/clay nanocomposites", Polymer, 44, 7953 (2003). https://doi.org/10.1016/j.polymer.2003.10.046
  6. V. Pasanovic-Zujo, R. K. Gupta, and S. N. Bhattacharya, "Effect of vinyl acetate content and silicate loading on EVA nanocomposites under shear and extensional flow", Rheol. Acta, 43, 99 (2004). https://doi.org/10.1007/s00397-003-0324-9
  7. C. Schneider, R. Langer, D. Loveday, and D. Haire, "Applications of ethylene vinyl acetate copolymers (EVA) in drug delivery systems", J. Control. Rel., 262, 284 (2017). https://doi.org/10.1016/j.jconrel.2017.08.004
  8. Y. Kong and J.N. Hay, "The enthalpy of fusion and degree of crystallinity of polymers as measured by DSC", Eur. Polym. J., 39, 1721 (2003). https://doi.org/10.1016/S0014-3057(03)00054-5
  9. P. Cebe, D. Thomas, J. Merfeld, B. P. Partlow, D. L. Kaplan, R. G. Alamo, A. Wurm, E. Zhuravlev, and C. Schick, "Heat of fusion of polymer crystals by fast scanning calorimetry", Polymer, 126, 240 (2017). https://doi.org/10.1016/j.polymer.2017.08.042
  10. J. E. K. Schawe, "Remarks regarding the determination of the initial crystallinity by temperature modulated DSC", Thermochim. Acta, 657, 151 (2017). https://doi.org/10.1016/j.tca.2017.09.006
  11. N. S. Murthy and H. Minor, "General procedure for evaluating amorphous scattering and crystallinity from X-ray diffraction scans of semicrystalline polymers", Polymer, 31, 996, (1990). https://doi.org/10.1016/0032-3861(90)90243-R
  12. T. H. Lee, F. Y. C. Boey, and K. A. Khor, "X-ray diffraction analysis technique for determining the polymer crystallinity in a polyphenylene sulfide composite", Polym. Compos., 16, 481 (1995). https://doi.org/10.1002/pc.750160606
  13. K. A. Moly, H. J. Radusch, R. Androsh, S. S. Bhagawan, and S. Thomas, "Nonisothermal crystallisation, melting behavior and wide angle X-ray scattering investigations on linear low density polyethylene (LLDPE)/ethylene vinyl acetate (EVA) blends: effects of compatibilisation and dynamic crosslinking", Eur. Polym. J., 41, 1410 (2005). https://doi.org/10.1016/j.eurpolymj.2004.10.016
  14. Y. Chen, H. Zou, M. Liang, and Y. Cao, "Melting and crystallization behavior of partially miscible high densitypolyethylene/ethylene vinyl acetate copolymer (HDPE/EVA) blends", Thermochim. Acta, 586, 1 (2014). https://doi.org/10.1016/j.tca.2014.04.007
  15. X. Ju, M. Bowden, E. E. Brown, and X. Zhang, "An improved X-ray diffraction method for cellulose crystallinity measurement", Carb. Polym., 123, 476 (2015). https://doi.org/10.1016/j.carbpol.2014.12.071
  16. C. Motta, "The effect of copolymerization on transition temperature of polymeric materials, J. Therm. Anal., 49, 461 (1997). https://doi.org/10.1007/BF01987471
  17. W. Stark and M. Jaunich, "Investigation of ethylene/vinyl acetate copolymer (EVA) by thermal analysis DSC and DMA", Polym. Test., 30, 236 (2011). https://doi.org/10.1016/j.polymertesting.2010.12.003
  18. X. M. Shi, J. Zhang, D. R. Li, and S. J. Chen, "Effect of damp-heat aging on the structures and properties of ethylene-vinyl acetate copolymers with different vinyl acetate contents", J. Appl. Polym. Sci., 112, 2358 (2009). https://doi.org/10.1002/app.29659
  19. H. A. Khonakdar, S. H. Jafari, A. Haghighi-Asl, U. Wagenknecht, L. Haeussler, and U. Reuter, "Thermal and mechanical properties of uncrosslinked and chemically crosslinked polyethylene/ethylene vinyl acetate copolymer blends", J. Appl. Polym. Sci., 103, 3261 (2007). https://doi.org/10.1002/app.25268
  20. K. Agroui, A. Maallemi, M. Boumaour, G. Collins, and M. Salama, "Thermal stability of slow and fast cure EVA encapsulant material for photovoltaic module manufacturing process", Sol. Energy Mater. Sol. Cells, 90, 2509 (2006). https://doi.org/10.1016/j.solmat.2006.03.023
  21. H. Varghese, T. Johnson, S. S. Bhagawan, S. Joseph, S. Thomas, and G. Groeninckx, "Dynamic mechanical behavior of acrylonitrile butadiene rubber/poly(ethylene-co-vinyl acetate) blends", J. Polym. Sci. B: Polym. Phys., 40, 1556 (2002). https://doi.org/10.1002/polb.10204
  22. A. Marcilla, J. A. Reyes-Labarta, and F. J. Sempere, "DSC kinetic study of the transitions involved in the thermal treatment of polymers. Methodological considerations", Polymer, 42, 5343 (2001). https://doi.org/10.1016/S0032-3861(00)00925-3
  23. V. Chevallier, M. Bouroukba, D. Petitjean, M. Dirand, J. Pauly, J. L. Daridon, and V. Ruffier-Meray, "Crystallization of a multiparaffinic wax in normal tetradecane", Fuel, 79, 1743 (2000). https://doi.org/10.1016/S0016-2361(00)00036-3
  24. H. S. Ashbaugh, A. Radulescu, R. K. Prudhomme, D. Schwahn, D. Richter, and L. J. Fetters, "Interaction of paraffin wax gels with random crystalline/amorphous hydrocarbon copolymers", Macromolecules, 35, 7044 (2002). https://doi.org/10.1021/ma0204047
  25. I. A. M. Al-Raheil and A. M. Okaz, "Chain-folding in polyethylene lamellar structure", Polym. Int., 28, 261 (1992). https://doi.org/10.1002/pi.4990280403
  26. J. D. Hoffman and R. L. Miller, "Kinetic of crystallization from the melt and chain folding in polyethylene fractions revisited: theory and experiment", Polymer, 38, 3151 (1997). https://doi.org/10.1016/S0032-3861(97)00071-2
  27. D. L. Dorset and B. K. Annis, "Lamellar order and the crystallization of linear chain solid solutions", Macromolecules, 29, 2969 (1996). https://doi.org/10.1021/ma9514277
  28. S. Patel, D. R. Nelson, and A. G. Gibbs, "Chemical and physical analyses of wax ester Properties", J. Insect Sci., 1, 4 (2001). https://doi.org/10.1673/031.001.0401
  29. S-S Choi and Y. Y. Chung, "Simple analytical method for determination of microstructures of poly(ethylene-co-vinyl acetate) using the melting points", Polym. Test., 90, 106706 (2020). https://doi.org/10.1016/j.polymertesting.2020.106706
  30. J. Zhang, C. Wu, W. Li, Y. Wang, and Z. Han, "Study on performance mechanism of pour point depressants with differential scanning calorimeter and X-ray diffraction methods", Fuel, 82, 1419 (2003). https://doi.org/10.1016/S0016-2361(03)00028-0