Abstract
Rutherford backscattering spectrometry has been used to determine the concentration against depth profiles of n-iodoalkanes diffusing into a polymer glass photoresist. All the iodoalkanes smaller than iodohexane show strongly non-Fickian, or Case II, diffusion. After an induction time a sharp front forms, with almost no concentration gradient behind the front. Ahead of the front the concentration decreases exponentially with depth, a form predicted for Fickian diffusion ahead of a moving boundary. Values of the diffusion coefficientD extracted from this Fickian precursor decrease strongly withn, the number of carbon atoms in the iodoalkane. A similar decrease is observed for the front velocity, the magnitude of which is in qualitative agreement with that predicted by the Thomas and Windle model of Case II diffusion. For the larger values ofn, D decreases asn −2, prompting speculation that these longer chains diffuse into the glass by a reptation-like mechanism.
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References
J. Crank andG. S. Park,Trans. Faraday Soc. 82 (1951) 1072.
J. Crank,J. Polym. Sci. 11 (1953) 151.
G. S. Park,ibid. 11 (1953) 97.
E. Bagley andF. A. Long,J. Amer. Chem. Soc. 77 (1955) 2172.
A. C. Newns,Trans. Faraday Soc. 52 (1956) 1533.
R. A. Ware andC. Cohen,J. Appl. Polym. Sci. 25 (1980) 717.
R. A. Ware, S. Tirtowidjojo andC. Cohen,ibid. 26 (1981) 2975.
H. L. Frisch, T. T. Wang andT. K. Kwei,J. Polym. Sci. A2 7 (1969) 872.
T. T. Wang, T. K. Kwei andH. L. Frisch,ibid. 7 (1969) 2019.
A. Peterlin,J. Polym. Sci. B 3 (1965) 1083.
Idem, Makromol. Chem. 124 (1969) 136.
Idem, J. Res. NBS 81A (1977) 243.
G. S. Park, in “Diffusion in Polymers”, edited by J. Crank and G. S. Park (Academic Press, London, 1968) p. 114.
J. H. Petropolis andP. P. Rousis,J. Chem. Phys. 47 (1967) 1491.
Idem, J. Polym. Sci. C 22 (1969) 917.
J. H. Petropolis,J. Polym. Sci., Polym. Phys. 22 (1984) 183.
G. Sarti,Polymer 20 (1979) 827.
N. L. Thomas andA. H. Windle,ibid. 23 (1982) 529.
L. Nicolais, E. Dricoli, H. B. Hopfenberg andD. Tidone,ibid. 18 (1977) 137.
N. L. Thomas andA. H. Windle,ibid. 18 (1977) 1195.
F. A. Long andD. Richmond,J. Amer. Chem. Soc. 82 (1960) 513.
P. J. Mills, C. J. Palmstrøm andE. J. Kramer,J. Mater. Sci. 21 (1986) 1479.
T. Alfrey,Chem. Eng. News 43 (1965) 64.
W.-K. Chu, J. W. Mayer andM.-A. Nicolet, “Backscattering Spectrometry” (Academic Press, New York, 1978) pp. 21–53.
H. S. Carslaw andJ. C. Jaeger, “Conduction of Heat in Solids” (Oxford University Press, Oxford, UK) p. 373.
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Mills, P.J., Kramer, E.J. The effect of molecular size on non-Fickian sorption in glassy polymers. J Mater Sci 21, 4151–4156 (1986). https://doi.org/10.1007/BF01106522
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DOI: https://doi.org/10.1007/BF01106522