N. Elkissi et al., EFFECT OF SURFACE-PROPERTIES ON POLYMER MELT SLIP AND EXTRUSION DEFECTS, Journal of non-Newtonian fluid mechanics, 52(2), 1994, pp. 249-261
The purpose of this study is to analyse the flow of a linear polydimet
hylsiloxane of high molecular weight on plane surfaces that may intera
ct differently with the silicone fluid used. Stainless steel surfaces
and slightly rough silicon surfaces were examined, including silica su
rfaces where monolayers of fluorine chains were grafted on by silanati
on reactions. The interest and principle of these reactions are briefl
y recalled. The quality of the surface treatment was checked by wettin
g experiments. For each ''fluid-wall material'' pair, flow rate measur
ements were performed under a given pressure. In addition, the extruda
te was photographed under various flow regimes. Combined analysis of t
he flow curves and observations at the die outlet helped to determine
the effect of roughness and of the wall material for the specific flow
conditions considered.