Relaxation of residual stress and reentanglement of polymers in spin-coated films.
Performing detailed studies of viscoelastic dewetting of thin polystyrene films on solid substrates, we demonstrate the existence of residual stress due to strongly out of equilibrium chain conformations and a reduced entanglement density resulting from film preparation by spin coating. The ratio of stress over elastic modulus was found to increase strongly with decreasing film thickness and increasing chain length. Full equilibration of chain conformations required long times comparable to bulk reptation times. However, for chains longer than about 3000 monomers, the residual stress relaxed faster, at a rate independent of chain length.
Damman
Pascal
P
Laboratoire de Physicochimie des Polymères, Centre d'Innovation et de Recherche en Matériaux Polymères, Université de Mons Hainaut, 20, Place du Parc, B-7000 Mons, Belgium. pascal.damman@umh.ac.be
Gabriele
Sylvain
S
Coppée
Séverine
S
Desprez
Sylvain
S
Villers
Didier
D
Vilmin
Thomas
T
Raphaël
Elie
E
Hamieh
Moustafa
M
Akhrass
Samer Al
SA
Reiter
Günter
G