Dresden 2009 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
CPP: Fachverband Chemische Physik und Polymerphysik
CPP 6: Thin Films
CPP 6.2: Talk
Monday, March 23, 2009, 14:15–14:30, ZEU 160
Surface enrichment layers in pressure sensitive adhesive films — •Alexander Diethert1, Stephan V. Roth2, and Peter Müller-Buschbaum1 — 1TU München, Physik Department LS E13, James-Franck-Str.1, 85748 Garching (Germany) — 2HASYLAB at DESY, Notkestr. 85, D-22603 Hamburg (Germany)
Pressure sensitive adhesives (PSAs) are used for many different applications, such as for example adhesive foils or binding materials. A prominent class of PSA films is based on statistical copolymers. Typically, two or three different monomers are combined to balance the different requests of the PSA. The adhesive properties of the PSA films are mainly determined by surface-near regions. However, detailed structural information about this region is still missing.
In the presented work we focus on PSA model systems of statistical copolymers consisting of two different types of monomers: a tacky monomer (e.g. ethyl hexylacrylate) and a glassy monomer (e.g. methyl methacrylate). The PSA films were prepared with solution casting.
From a naive point of view, one would have expected homogenous films which are characterized by the average monomer composition. To investigate the surface structure, we probed the density profile perpendicular to the PSA surface using x-ray reflectivity (XRR). We detected an oscillating composition profile depending on the chosen monomers, the molecular weight of the polymer and the sample age.
Lateral structures within the surface near region are probed with grazing incidence small angle x-ray scattering (GISAXS).