Shape Effects on the Structure and Response of the Polymeric Particles Synthesized from Cholesteric Liquid Crystal Templates

2021-01-01
Avşar, Deniz Işınsu
Büküşoğlu, Emre
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: Liquid crystals (LCs) have been shown to provide molecular templates for the synthesis of polymeric particles. Past studies have revealed the elastic effects to dominate internal configuration of the LC molecular templates for the sizes below 10 µm. Sacrificial microwells were used in this study to study the effect of shapes of the particles synthesized from the cholesteric liquid crystals on their structure and response. Specifically, mixtures of diacrylate based reactive (RM257) and nonreactive mesogens (E7), and chiral dopant (S811) were initially filled into circular, triangular, square and star shaped microwells made from polyvinyl alcohol. After photopolymerization followed by the extraction of the non-reactive part, the particles were obtained. Optical and responsive characterization of the particles showed that the elastic effects of the liquid crystals can also be observed within the particles of the sizes of 50 µm, significantly above the usually expected sizes. We found that the three-dimensional confinement, inhomogeneous surface anchoring and the cholesteric symmetry to play a critical role in the dominant effect of elasticity at larger sizes. The findings of this study will be used in the design of responsive polymeric particles used in the sensing of the vapors of volatile organic compounds.
Liquid Crystals, Particles, Polymerization, Color, Response, Sıvı Kristaller, Parçacıklar, Polimerizasyon, Renk, Tepki
https://dergipark.org.tr/en/download/article-file/1384011
https://hdl.handle.net/11511/96442
Erciyes Üniversitesi Fen Bilimleri Enstitüsü Dergisi
Department of Chemical Engineering, Article

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Citation Formats
D. I. Avşar and E. Büküşoğlu, “Shape Effects on the Structure and Response of the Polymeric Particles Synthesized from Cholesteric Liquid Crystal Templates,” Erciyes Üniversitesi Fen Bilimleri Enstitüsü Dergisi, pp. 0–0, 2021, Accessed: 00, 2022. [Online]. Available: https://dergipark.org.tr/en/download/article-file/1384011.
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