On study of X-ray absorption and properties of dispersion of W, MoS2 and B4C particles in high density polyethylene

Document Type : Research Article

Authors

Department of Polymer Processing, Iran Polymer and Petrochemical Institute, Tehran, Iran

Abstract

Shielding radiation from both x-rays and gamma-rays is important for personnel in medical fields e.g. interventional radiology, nuclear power stations, and other inspection facilities where radiation is involved. Lead is known for its effective shielding property against these high energy radiations, however heaviness and toxicity are its main drawback. In this study effectiveness of non-lead polymeric composite materials, which include high-atomic-number / or known barrier elements to absorb photons from the radiations was evaluated. High density polyethylene as matrix and powders of spherical W and lamellar MoS2 and B4C as particulate fillers with different loadings were melt mixed in an internal mixer, followed by compression molding in to sheet form. The goodness of dispersion was manifested via SEM and EDX images. Radiation attenuation capability of these compounds was examined with direct diagnostic x-ray exposure and compared with that of Pb. Dynamic rheology measurements were carried out to evaluate viscoelastic properties of the molten composite materials, necessary in shaping process operations. The mechanical and thermal properties were further investigated from the product performance point of view. Results demonstrated that the flexible composite sheet made with 45% (wt) tungsten provided comparable x-ray absorption to non-flexible lead sheet but much lighter in weight. Significant difference was observed between flow characteristics and yield strength of composite materials of highly loaded spherical metallic particles and lamellar particles of metallic compounds. The melt viscoelastic behavior of former was similar to that of neat matrix melt.

Highlights

  • 45% (wt) tungsten powder dispersed in HDPE has a comparable x-ray shielding performance to lead.
  • This developed composite material also has γ-ray radiation attenuation capability with no degradation in its polymer matrix.
  • The highly W filled material has the same processability as its neat polymer constituent.
  • Enhancement of yield stress and strength of HDPE with W loading imparts better load bearing performance.

Keywords

References

[1] X. Cao, X. Xue, T. Jiang, Z. Li, Y. Ding, H. Yang, Mechanical properties of UHMWPE/Sm2O3 composite shielding material, J. Rare Earth., 28 (2010) 482-484.
[2] S. Navas, Study of the neutron shielding capacity of different carbon materials for space application, Dep. Space Programs and Sciences, National Institute of Aerospace Technology. (2016).
[3] S. Nambiar, J.T. Yeow, Polymer-composite materials for radiation protection, ACS Appl. Mater. Inter., 4 (2012) 5717-5726.
[4] A. Bhattacharya, Radiation, industrial polymers, Prog. Polym. Sci., 25 (2000) 371-401.
[5] C. Harrison, S. Weaver, C. Bertelsen, E. Burgett, E. Grulke, Polyethylene/boron nitride composites for space radiation shielding, J. Appl. Poly. Sci., 109 (2008) 2529-2538.
[6] K. Yue, W. Luo, X. Dong, C. Wang, G. Wu, M. Jiang, A new lead-free radiation shielding material for radiotherapy, Radiat. Prot. Dosim., 133 (2009) 256-260.
[7] T. Ivanoua, K. Bliznakova, N. Pallikarakis, Simulation studies of field shaping in rotational radiation therapy, J. Med. Phys., 33 (2006) 4289-4298.
[8] A. El-Sayed Abdo, M.A.M. Ali, M.R. Ismail, Natural fiber high-density polyethylene and lead oxide composites for radiation shielding, Radiat. Phys. Chem., 66 (2003) 185-195.
[9] J.R. Gaier, W. Hardebeck, J.R.T. Bunch, M.L. Davidson, D.B. Beery, Effect of interaction in graphite epoxy composites on the shielding of high energy radiation, National aeronautics and space administration, Washington, D.C., 1997.
[10] E. Najafi, K. Shin, Radiation resistance polymer-carbon nanotube nanocomposite thin films, Colloid. Surface. A, 257-258 (2005), 333-337.
[11] L.M. Clayton, T.G. Gerasimor, M. Cinke, M. Meyyappan, J.P. Harmon, Dispersion of Single-Walled Carbon Nanotubes in a Non-Polar Polymer, Poly(4-methyl-1-pentene), J. Nanosci. Nanotechno., 6 (2006) 2520-2524.
[12] G. Gnduz, A. Usanmaz, A development of new nuclear shielding materials containing vitrified colemanite and impregnated polymer, J. Nucl. Mater., 140 (1986) 4-55.
[13] M.M. Ashton-Patton, M.M. Hall, J.E. Shelby, Formation of low density polyethylene/ hollow glass microspheres composites, J. Non-Cryst. Solids, 352 (2006) 615-619.
[14] C. Harrison, S. Weaver, C. Bertelsen, E. Burgett, N. Hertel, Radiation Oncology Physics, Polyethylene/boron nitride composites for space radiation shielding, J. Appl. Polym. Sci., 109 (2008) 2529-2538.
[15] J. Kim, B. Lee, Y, Rang, Enhancement of thermal neutron attenuation of nano-B4C, -Bn dispersed neutron shielding polymer composites, J. Nucl. Mater., 453 (2014) 48-53.
[16] T.F. Tadros, Rheology of Dispersions: Principles and Applications, Wiley-Vch, New York, 2010.
[17] F.M. Mirabella, A. Bafna, Determination of the crystallinity of polyethylene/α-olefin copolymers by thermal analysis: Relationship of the heat of fusion of 100% polyethylene crystal and the density, J. Polym. Sci., 15 (2002) 1637-1643.
[18] Y. Kim, S. Park, Y. Seo, Enhanced X-ray shielding ability of polymer-nonleaded metal composites by multilayer structuring, Ind. Eng. Chem. Res., 54 (2015) 5968-5973.
Journal of Particle Science and Technology
Volume 3, Issue 1
March 2017
Pages 13-24

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History

  • Receive Date: 25 January 2017
  • Revise Date: 04 July 2017
  • Accept Date: 23 September 2017

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