Eur. Phys. J. E 2, 359-365
Viscosity critical behaviour at the gel point in a 3d lattice model
E. Del Gado1 - L. de Arcangelis2 - A. Coniglio1
1 Dipartimento di Scienze Fisiche, Università di Napoli
"Federico II'', INFM Sezione di Napoli, Mostra d'Oltremare pad.
19, 80125 Napoli, Italy
2 Dipartimento di Ingegneria
dell'Informazione, Seconda Università di Napoli, INFM Sezione di
Napoli, via Roma 29, 81031 Aversa (Caserta), Italy
This email address is being protected from spambots. You need JavaScript enabled to view it.
Received 20 December 1999 and Received in final form 18 February 2000
Abstract
Within a recently introduced model based on the
bond-fluctuation dynamics, we study the viscoelastic behaviour of a
polymer solution at the gelation threshold. We here present the
results of the numerical simulation of the model on a cubic
lattice: the percolation transition, the diffusion properties and
the time autocorrelation functions have been studied. From both the
diffusion coefficients and the relaxation times critical behaviour
a critical exponent k for the viscosity coefficient has been
extracted: the two results are comparable within the errors giving
,
in close agreement with the Rouse model prediction and
with some experimental results. In the critical region below the
transition threshold the time autocorrelation functions show a long-time
tail which is well fitted by a stretched exponential decay.
PACS
05.20.-y Classical statistical mechanics
- 82.70.Gg gels and sols
- 83.10.Nn Polymer dynamics
Copyright EDP Sciences, Società Italiana di Fisica, Springer-Verlag
