Free volume-limited diffusion in ion-modified polymers

✍ Scribed by V. Švorčík; V. Rybka; O. Jankovskij; V. Hnatowicz

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 335 KB
• Volume: 61
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19960815)61:7<1097::aid-app4>3.0.co;2-h

✦ Synopsis

Iodine diffusion in ion-modified polyethylene (PE) using the Rutherford Backscattering method (RBS) has been studied. P E was irradiated by N+, Ar+ and As+ ions with an energy of 150 keV and doses of 1 X 1013-1 X 1015 cm12. Iodine diffused in ion-modified PE from vapor at 9OoC. Iodine's concentration profile changed its shape dramatically for ion doses over 1 X cm-' when it showed two maxima. A similar profile was exhibited by oxygen, which diffused in P E on implantation. Iodine's concentration dropped in the layer where the most significant polymer carbonization occurred. This range was found ahead of the implanted ions concentration. Iodine diffusion was most intensive for lower ion doses ( 5 1 X cm-2) while for higher doses it was substantially slower due to P E carbonization. The reason was the lower free volume in the PE carbonized layer as compared with the layer where the polymer's degradation was not reflected in such a significant increase in carbon content.