Equilibrium interaction of solid surfaces across a polymer melt.
Forces across polymer melts are poorly understood despite their importance for adhesion and fabricating composite materials. Using an atomic force microscope (AFM), this interaction was measured for poly(dimethyl siloxane) (PDMS). The structure of the polymer at the surface changed during the first approximately 10 h. Afterward, short-range attractive forces were observed with short-chain PDMS (M(w) = 4200 g/mol). Using PDMS with a molecular weight (M(w) = 18 000 g/mol) above the entanglement limit, we measured a monotonically decaying repulsive force, which indicates that a quasi-immobilized layer had formed at the solid surface. Due to the small radius of curvature of the tip, forces could be measured in equilibrium.
Sun
Gexiao
G
Max-Planck-Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany.
Kappl
Michael
M
Pakula
Tadeusz
T
Kremer
Kurt
K
Butt
Hans-Jürgen
HJ
D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D018625:Microscopy, Atomic Force / Q000379:methods; D008970:Molecular Weight; D012680:Sensitivity and Specificity; D013499:Surface Properties
D004129:Dimethylpolysiloxanes