Synthesis and magnetic properties of mesogenic side-chain polymers containing stable radicals

An amorphous and a liquid-crystalline side-chain polymer containing stable nitroxyl radicals are synthesized, the free radical being located either in a piperidine N-oxyl or a 1,3-oxazolidine N-oxyl moiety. These polymers are available by reaction of precursor polymer having a formyl group in every repeating unit with low-molecular-weight nitroxyl free radicals functionalized with an amino group. The conversion of the polymer-analogous reaction is nearly quantitative. Both the amorphous and the liquid-crystalline polymer show paramagnetic behaviour in the temperature range from 6 to 300 K.