In this experiment elastic light scattering (Rayligh- and Mie-Scattering) in the form of dynamical light scattering (DLS) is employed. From the time and scattering angle dependent intensity, structural and dynamical temperture dependent characteristics of the microgelpartilces are investigated.

(Nanometer) small particles are applied in numerous industrial application ranging from chemistry, medicine, pharmacy to paint industry – to name a few. For example, gold nanoparticles are interesting as model systems as an alternative for dyes. Their colour impression depends on the spectral absorption of photons, which is given by its dielectric function – a function that depends on shape, size and surrounding dielectrics in addition to material constants.

In this experiment PolyNIPAM(microgel)- and Polystyrene-particles serve as nanoparticles. In contrast to Polystyrene, PolyNIPAM is a temperature sensitive macrolmolecule that is hydrophillic up to ~32°C and hydrophobic above this temperature. As consequence PolyNIPAM is in a swollen conformation at temperatures below and in collapsed state when above 32°C.