Stretching a polymer brush by making in situ cyclodextrin inclusion complexes.

The interaction between poly(ethylene oxide) (PEO) chains grafted onto polystyrene latex particles and alpha-, beta-, and gamma-cyclodextrins (CD) was studied by small-angle neutron scattering. The particles were contrast-matched to the solvent in order that only the scattering from the polymer layers was detected. The signal from the layers was fitted to a double-exponential volume fraction profile. The effects of adding cyclodextrin on the polymer profile are shown as a function of cyclodextrin concentration. The polymer layers are seen to extend on addition of CD, which is consistent with a complexation between the grafted PEO and the CD molecules. The effect is the strongest with alpha-CD.