Changes of Free Radical Content in Exposed to Electrons GUR1020 and GUR1050 Polyethylene Types Intended for Endoprosthesis Acetabular Cups

Abstract:

The paper presents the results of the EPR examination of free radical content in GUR1020 and GUR1050 polyethylenes which were irradiated with an electron beam. Changes in the amount of radicals in the period of 12 months in the UHMWPE cross-linked with a dose of 26-156 kGy were analysed. Spectra registered 90 days after irradiation show a hyperfine structure. An image consisting of 7 characteristic lines is the most similar pattern that can be used to analyse this spectrum. Subsequent measurements (255 and 372 days after irradiation) produce images consisting of one resonance line. Alkyl and allyl radicals generated during the irradiation are the source of the EPR signal. The influence of atmospheric oxygen causes further changes of the radicals mentioned above, which leads to the formation of peroxyl radicals. The content of radicals in the polymer and its changes over time were calculated. The amount of radicals increases as the absorbed dose grows, but decreases over time. Comparative measurements of the material subjected to thermal processing at the temperature of 423 K have shown that in this case, no resonance lines are present, which testifies to the effective elimination of free radicals by means of UHMWPE recrystallisation.

• Periodical: Solid State Phenomena (Volume 199)
• Pages: 544-549
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.199.544
• Online since: March 2013
• Authors: Piotr Czaja, Joanna Maszybrocka, Jacek Michniowski, Jerzy Cybo, Adrian Barylski
• Keywords: Electron Beam Irradiation, EPR, Free Radical, UHMWPE

References

[1] K.W. Greer, J.W. Hamilton, Polyethylene wear in orthopedies, J&JP. Inc., (1994).

[2] K. Pruski, A. Górecki, T. Jabłoński, Tactics of coping with hip joint acetabular coups' revision operations, Ortopedia Traumatologia Rehabilitacja 3 (2001) 15-20.

[3] A.A. Edidin, C.M. Rimnac, V.M. Goldberg, S.M. Kurtz, Mechanical behaviour wear surface morphology and clinical performance of UHMWPE acetabular components after 10 years of implantation, Wear 250 (2001) 152-158.

DOI: 10.1016/s0043-1648(01)00616-0

[4] O.K. Muratoglu, J.L. Cook, M. Jasty, W.H. Harris, A novel technique to measure the cross-link density of irradiated UHMWPE, Trans 44th Orthop. Res. Soc. 23 (1998) 782.

[5] C.J. Bell, P.S. Walker, M.R. Abeysundera, J.M. Simmons, P.M. King, G.W. Blunn, Effect of oxidation on delamination of ultrahigh-molecular-weight polyethylene tibial components, J. Arthroplasty 3 (1998) 280-290.

DOI: 10.1016/s0883-5403(98)90173-5

[6] J. Cybo, J. Maszybrocka, A. Barylski, J. Kansy, Resistance of UHMWPE to plastic deformation and wear and the possibility of its enhancement through modification by radiation, Journay of Applied Polimer Science DOI 10. 1002/app. 36573.

DOI: 10.1002/app.36573

[7] B. Rånby, J.F. Rabek, ESR Spectroscopy in Polymer Research, Springer Verlag, (1977).

[8] M. K. Steven, UHMWPE Biomaterials Handbook, Academic Press is an imprint of Elsevier 2009, pp.433-450.

[9] A. M. Visco, N. Campo, L. I. Vagliasindi, G. Tabbi, Study of the radical species induced by electron-beam irradiation in vacuumon biomedical UHMWPE, International Journal of Polymer Anal. Charact. 15 (2010) 424-437.

DOI: 10.1080/1023666x.2010.510109

[10] M. S. Jahan, M. C. King, W. O. Haggard, K. L. Sevo, J. E. Parr, A study of long-lived free radicals in gamma-irradiates medical grade polyethylene, Radiation Physics and Chemistry 62 (2001) 141-144.

DOI: 10.1016/s0969-806x(01)00431-5

[11] P. Czaja, J. Cybo, J. Maszybrocka, A. Barylski, J. Michniowski, The EPR method investigation of free radicals in polymer UHMWPE applied in the biomedical knots of the friction, Tribologia 5 (2011) 39-47.

[12] A. Więckowski, Mathematical analysis of the exchange-narrowed EPR line, Poznańskie Towarzystwo Przyjaciół Nauk VII (1975) 101-119.

[13] D. L. Griscom, Electron Spin Resonance in Glasses, Journal of Non-Crystalline Solid 40 (1980) 211-272.

DOI: 10.1016/0022-3093(80)90105-2

[14] E. Oral, Ch. G. Beckos, O. K. Muratoglu, Free radical elimination in irradiated UHMWPE through crystal mobility in phase transition to the hexagonal phase, Polymer 49 (2008) 4733-4739.

DOI: 10.1016/j.polymer.2008.07.049

[15] V. Premnath, W. H. Harris, M. Jasty, E. W. Merrill, Gamma sterilization of UHMWPE articular implants: an analysis of the oxidation problem, Biomaterials 17 (1996) 1741-1753.

DOI: 10.1016/0142-9612(95)00349-5

[16] L. Costa, I. Carpentieri, P. Bracco, Post electron-beam irradiation oxidation of orthopaedic UHMWPE, Polymer Degradation nad Stability 93 (2008) 1695-1703.

DOI: 10.1016/j.polymdegradstab.2008.06.003

[17] J. Maszybrocka, J. Cybo, A. Barylski, P. Czaja, Changes in UHMWPE morphology and structure after with an electron beam and thermal treatment, Solid State Phenomena 2012 (in print).

DOI: 10.4028/www.scientific.net/ssp.199.538