The synthesis, morphology and liquid-crystalline property of polysiloxane-modified perylene derivative

A novel polysiloxane-modified perylene derivative was designed and synthesized through the amidation reaction between aminopropyl-terminal polysiloxane and perylene tetracarboxylic diester monoimides with n-dodecyl as the alkyl chain connected to the perylene core. The synthesized compound was subjected to IR and 1H NMR. The liquid-crystalline property of the modified perylene derivative at room temperature (ranged from 27.1 °C to 61.3 °C) was characterized via differential scanning calorimetry, polarization optical microscope, X-ray powder diffraction, and small-angle X-ray scattering. The morphology of the compound was evaluated via scanning electron microscopy and atomic force microscopy in tapping mode. The static contact angle of the perylene derivative with distilled water as the test liquid was improved after modification by polysiloxane. All the measurements revealed that the polysiloxane-modified perylene derivative exhibited good thermal stability, excellent optical property, good hydrophobic property, and low temperature liquid-crystalline property. These properties may be attributed to the presence of flexible Si–O–Si chain and ordered π–π* stacking between adjacent perylene cores.

► Synthesis method of polysiloxane-modified perylene derivative had high yield.
► The desired product owned excellent optical property.
► It also had hydrophobic liquid-crystalline property under room temperature.
► It had good thermal stability and can be used as high-temperature material.