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CPP: Chemische Physik und Polymerphysik
CPP 35: Single molecules I
CPP 35.3: Vortrag
Mittwoch, 9. März 2005, 10:15–10:30, TU C243
Fluorescence Correlation Spectroscopy Investigations of Water-soluble Polymers — •T. Bonne1, K. Lüdtke2, R. Jordan2, P. Stepanek3, R. Ivanova1, and C. M. Papadakis1 — 1Physik Department E13, TU München, Germany — 2Chemie Department, TU München, Germany — 3Inst. Macromol. Chem., Prague
The diffusional behavior of 2-alkyl-2-oxazoline based on homo- and block copolymers in aqueous solution is studied using fluorescence correlation spectroscopy (FCS). The hydrophobicity can be varied continuously by changing the length of the alkyl side chain, and fluorescence groups can be attached. The chain length dependence of the diffusion coefficient of a series of low molar mass poly(2-methyl-2-oxazoline)s is in good agreement with a model based on rod-like particles. Furthermore, FCS allowed us to determine the very low critical micelle concentration (CMC) of amphiphilic poly[(2-methyl-2-oxazoline)-b-(2-nonyl-2-oxazoline)] diblock copolymers in aqueous solution (< 10−5 M). With dynamic light scattering we were able to determine the same micellar hydrodynamic radius as with FCS, but the CMC was below the detection limit [1].
[1] T. B. Bonné et. al (2004), Coll. Polym. Sci. 282: 833.