Low-voltage-driven and highly-diffractive holographic polymer dispersed liquid crystals with spherical morphology

Peng, H., Yu, L., Chen, G., Bohl, T. W., Ye, Y., Zhou, X., Xue, Z., Roy, V.A.L. and Xie, X. (2017) Low-voltage-driven and highly-diffractive holographic polymer dispersed liquid crystals with spherical morphology. RSC Advances, 7(82), pp. 51847-51857. (doi: 10.1039/c7ra08949j)

Abstract

It is a constant pursuit to form highly-diffractive and low-voltage-driven holographic polymer dispersed liquid crystals (HPDLCs) for meeting the requirements of practical applications. Nevertheless, the high-voltage-driven characteristic is usually given while improving the diffraction efficiency of HPDLCs, and it remains a challenge to form HPDLCs with concurrent features of high diffraction and low driving voltage via a simple method. In this work, we synthesize a non-room-temperature LC, 4-butyloxy-4′-cyanobiphenyl (4OCB), and mix it with a room-temperature nematic LC mixture named P0616A. These new LC mixtures are then homogeneously mixed with monomers and a photoinitibitor composed of 3,3′-carbonylbis(7-diethylaminocoumarin) (KCD) and N-phenylglycine (NPG), followed by patterning via laser interference, generating well-structured HPDLCs. The introduction of 4OCB into the standard formulation is found to be able to optimize the morphology and electro-optical properties of the resulting HPDLC transmission gratings. By doping 5 wt% of 4OCB into the HPDLCs, a high diffraction efficiency of 92 ± 3% is obtained; meanwhile, the threshold and saturated voltages significantly decrease by 80.8% (i.e., from 12.0 ± 0.8 to 2.3 ± 0.9 V μm−1) and 73.2% (i.e., from 19.0 ± 0.6 to 5.1 ± 0.7 V μm−1), respectively, in comparison with the pristine. The enhanced performance is believed to be ascribed to the formed larger LC droplets (70 ± 20 nm) and lower interface anchoring strength (0.7 μN m−1) of the polymer network on LCs.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Vellaisamy, Professor Roy
• Authors: Peng, H., Yu, L., Chen, G., Bohl, T. W., Ye, Y., Zhou, X., Xue, Z., Roy, V.A.L., and Xie, X.
• College/School: College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: RSC Advances
• Publisher: Royal Society of Chemistry
• ISSN: 2046-2069
• ISSN (Online): 2046-2069
• Published Online: 07 November 2017
• Copyright Holders: Copyright © 2017 The Authors
• First Published: First published in RSC Advances 7:51847–51857
• Publisher Policy: Reproduced under a Creative Commons Licence

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