Cholesteric Liquid Crystal Based Polymeric Sensors for Detection of Volatile Organic Compounds

Date

2018-08-30

Author

Batır, Özge
Bat, Erhan
Büküşoğlu, Emre

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Polymeric materials have gained a recent interestespecially in sensor technology. Optical properties of polymeric sensors can betuned by templating the polymer network by liquid crystals (LCs).[1]LCs are stable fluid phases that possess molecular ordering. When a chiraldopant is added, helical twisting of the molecular directional order (n) can beinduced leading to a cholesteric liquid crystalline (CLC) phase.[2] CLCsexhibit a wavelength and polarization selective reflection due to theirperiodic helical structure. The periodic helical structure, therefore the wavelengthof the reflected light, has been shown to be influenced by various externalstimuli, such as temperature, electricity and chemicals.[3]Therefore, the presence of the chemical vapors can be identified according toextend of the change in the color appearance of the polymeric films templatedfrom CLCs. In this study, CLC-templated polymeric films were fabricated in thepresence of strain orthogonal to the molecular director and tested for sensorapplications in a controlled experimental system where the concentration of thevolatile organic compound (VOC) is controlled. Upon exposure to VOC vapor, weobserved a color change that is influenced by the amount of strain on thecholesteric axis of the polymeric sensor.

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https://hdl.handle.net/11511/84568

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Citation Formats

Ö. Batır, E. Bat, and E. Büküşoğlu, “Cholesteric Liquid Crystal Based Polymeric Sensors for Detection of Volatile Organic Compounds,” 2018, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/84568.