AbstractThe rotational dynamic behaviour of a polymer of the hairy rod type has been investigated in the solid state. Octa‐(alkoxy)‐phthalocyaninatopolysiloxanes have been synthesized selectively deuterated at the aromatic core positions for this study. They form a hexagonal columnar structure without any phase change in the temperature range from 170 to 470 K. Thermally activated uniaxial rotation involving the phthalocyanato moiety around the long axis of the polymer is detected by solid‐echo2H‐NMR spectroscopy. Two‐dimensional NMR spectroscopy shows that the motional process involves 90° jumps with considerable broadening of the reorientation potential, reflecting the four‐fold symmetry of the repeat unit. This indicates that the siliconphthalocyanine moieties can rotate around their covalent Si‐O bond within a single macromolecule, rather than the molecules as a whole around their