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The Influence of Deformation and Chemical Composition on Elementary Free Volumes in Glassy Polymers

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Shantarovich V., Novikov Y., Suptel Z., Oleinik E., Boyce M.

Acta Physica Polonica A

1999

vol. 95

issue 4

659-662

A relation between positronium annihilation characteristics and concentration of elementary free volumes is considered for the case of positronium formation before its localization. We estimated the diffusion coefficient of nonlocalized positronium (≈10^{-4} cm^{2}/s). The positron annihilation lifetime studies of uniaxial compression and annealing of some glassy polymers revealed variations of the shape of elementary free volumes size-distributions.

Comments on the Effect ofγ-Irradiation on Positronium Formation in Polymers at Low Temperatures

100%

Shantarovich V., Hirade T., Kevdina I., Gustov V., Oleinik E.

Acta Physica Polonica A

2001

vol. 99

issue 3-4

497-501

Quantitative description of the effect of γ-irradiation of PE and PMMA on positronium formation on the trapped electrons at low temperatures is suggested. The consideration shows that, at least in these substances, the number of the trapping centers is probably enough to localize all ortho-positronium, and therefore the intensity of the long-lived positronium component is dependent mostly on the probability of Ps formation but not on the number of the trapping centers.

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2 Acta Physica Polonica A

1 2001

1 1999

2 Oleinik E.

2 Shantarovich V.

1 Boyce M.

1 Gustov V.

1 Hirade T.

1 Kevdina I.

1 Novikov Y.

1 Suptel Z.

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The Influence of Deformation and Chemical Composition on Elementary Free Volumes in Glassy Polymers

Comments on the Effect ofγ-Irradiation on Positronium Formation in Polymers at Low Temperatures