INQUIMAE   12526
INSTITUTO DE QUIMICA, FISICA DE LOS MATERIALES, MEDIOAMBIENTE Y ENERGIA
Unidad Ejecutora - UE
artículos
Título:
Numerical Simulations of Stick Percolation: Application to the Study of Structured Magnetorheological Elastomers
Autor/es:
J.L. MIETTA; R. M. NEGRI; P. I. TAMBORENEA
Revista:
JOURNAL OF PHYSICAL CHEMISTRY C
Editorial:
AMER CHEMICAL SOC
Referencias:
Lugar: Washington; Año: 2014 vol. 118 p. 20594 - 20604
ISSN:
1932-7447
Resumen:
In this article we explore how structural parameters of composites
filled with one-dimensional, electrically conducting elements (such as
sticks, needles, chains, or rods) affect the percolation properties of
the system. To this end, we perform Monte Carlo simulations of
asymmetric two-dimensional stick systems with anisotropic alignments. We
compute the percolation probability functions in the direction of
preferential orientation of the percolating objects and in the
orthogonal direction, as functions of the experimental structural
parameters. Among these, we considered the average length of the sticks,
the standard deviation of the length distribution, and the standard
deviation of the angular distribution. We developed a computer algorithm
capable of reproducing and verifying known theoretical results for
isotropic networks and which allows us to go beyond and study
anisotropic systems of experimental interest. Our research shows that
the total electrical anisotropy, considered as a direct consequence of
the percolation anisotropy, depends mainly on the standard deviation of
the angular distribution and on the average length of the sticks. A
conclusion of practical interest is that we find that there is a wide
and well-defined range of values for the mentioned parameters for which
it is possible to obtain reliable anisotropic percolation under
relatively accessible experimental conditions when considering
composites formed by dispersions of sticks, oriented in elastomeric
matrices.