RT Journal Article
T1 Annealing-induced enhancement of the gas diffusivity in coextruded LLDPE films investigated by positron lifetime spectroscopy
A1 Monge, M. A.
A1 García Villaluenga, Juan Pedro
A1 Muñoz, A.
A1 Leguey, T.
A1 Pareja, R.
AB The annealing effect on coextruded linear low-density polyethylene (LLDPE) films has been investigated by positron annihilation lifetime spectroscopy (PALS). From the continuous positron lifetime distribution found for these films, the size distribution of the free-volume holes in the amorphous phase is calculated, as well as their fractional free volume. Also, diffusivity measurements at 298 K for He, O-2, and N-2 and X-ray diffraction measurements have been performed. The results reveal that annealing induces changes in the hole size distribution and in the amorphous fractional free volume of the films, along with an enhancement of the gas diffusivity. The correlation found between the amorphous fractional free volume and diffusion coefficients agrees with the free-volume model for diffusion in polymers. Moreover, the results show that the probability density function of the free-volume holes has certain influence on the diffusion coefficients, revealing that the impedance factors for diffusion would be controlled by the size distribution shape of the free-volume holes in the amorphous phase.
SN 0024-9297
YR 2002
FD 2002-10-08
LK https://hdl.handle.net/20.500.14352/58970
UL https://hdl.handle.net/20.500.14352/58970
LA eng
NO © 2002 American Chemical Society. The research carried out at Universidad Carlos III de Madrid was supported byConsejería de Educación de la Comunidad Autónoma de Madrid (Spain) under the auspices of the Financing Program for Strategic Research Groups. The authors are grateful to Dr. B. Seoane for useful discussions.
NO Consejería de Educación de la Comunidad Autónoma de Madrid (Spain)
DS Docta Complutense
RD 5 abr 2025