Viscoelasticity near the gel point: A molecular dynamics study - art. no. 031505

Citation
D. Vernon et al., Viscoelasticity near the gel point: A molecular dynamics study - art. no. 031505, PHYS REV E, 6403(3), 2001, pp. 1505
Citations number
31
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW E
ISSN journal
1063651X → ACNP
Volume
6403
Issue
3
Year of publication
2001
Part
1
Database
ISI
SICI code
1063-651X(200109)6403:3<1505:VNTGPA>2.0.ZU;2-S
Abstract
We report on extensive molecular dynamics simulations on systems of soft sp heres of functionality f. i.e., particles that are capable of bonding irrev ersibly with a maximum of f other particles. These bonds are randomly distr ibuted throughout the system and imposed with probability p. At a critical concentration of bonds. p(c) approximate to 0.2488 for f = 6, a gel is form ed and the shear viscosity eta diverges according to eta similar to (p(c)-p )(-s). We find s approximate to 0.7 in agreement with some experiments and with a recent theoretical prediction based on Rouse dynamics of phantom cha ins. The diffusion constant decreases as the gel point is approached but do es not display a well-defined power law.