Morphological Study of PDLC Films with Refractive Index Using Catalyst

Mujtaba Ellahi, Muhammad Nawaz, M. Yasir Rafique


In present study the smart glass films whose feed ratio based on Nemetic liquid crystal (LC) and epoxy resins through the polymerization induced phase separation (PIPS) technique. Study the applications in display technology to inspect the morphological activities and refractive indices of epoxy resins based PDLC films (Smart Glass)  using Tris(hydroxymethyl)amine as catalyst. In this study, best possible preparation condition was 20% LC, curing time 5 hrs at 90°C temperature. In this research, the refractive index of the domain size of PDLC films was studied using Abbe Refractometer at ambient temperature. The Tris(hydroxymethyl)amine have distorted the difference between the refractive indices of the polymer and the LC, and the aggregation increases the light scattering that could develop the morphological characteristics of the composites. In addition, PDLC films were prepared with different amounts of Tris(hydroxymethyl)amine to investigate the best ratio of the catalyst. It is revealed that when the weight feed ratio of LC was 20% in PDLC and 2% of Tris(hydroxymethyl)amine catalyst, then dispersed state of LC were well proportioned, and the variation of transmittance reached the highest value which noticeably affect the morphological characteristics of the composites. The refractive index of polymer matrix varied in the series due to the composition difference .Concurrently, these result lengthen the possible applications of epoxy resins smart glass thin films by choosing accurate compositions ratio, heating time, and catalyst reaction used for fabrications of smart films.

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Doane, J. W., Vaz, N. A., Wu, B. G., & Žumer, S. (1986). Field controlled light scattering from nematic microdroplets. Applied Physics Letters, 48(4), 269-271.

Bahadur, B. (Ed.). (1992). Liquid Crystals - Applications and Uses, Singapore: World Scientific.

Kitzerow, H. S. (1994). Polymer-dispersed liquid crystals from the nematic curvilinear aligned phase to ferroelectric films. Liquid Crystals, 16(1), 1-31.

Kim, Y. B., Park, S., & Hong, J. W. (2009). Fabrication of flexible polymer dispersed liquid crystal films using conducting polymer thin films as the driving electrodes. Thin Solid Films, 517(10), 3066-3069.

Park, S., & Hong, J. W. (2009). Polymer dispersed liquid crystal film for variable-transparency glazing. Thin Solid Films, 517(10), 3183-3186.

Ellahi, M., Gao, Y., & Rafique, M. Y. (2013). Influence of enhanced curing temperature of epoxy monomers structure on the electro-optical properties and morphology of polymer-dispersed liquid crystal films. American Journal of Engineering Research, 2(3), 01-06.

Lee, S. H., Lee, S. L., & Kim, H. Y. (1998). Electro-optic characteristics and switching principle of a nematic liquid crystal cell controlled by fringe-field switching. Applied physics letters, 73(20), 2881-2883.

Ellahi, M., Gao, Y., & Yang, H. (2013). Effects of di and tetra functional epoxy monomers structure on the morphology and the electro-optical properties of polymer-dispersed liquid crystal films. International Journal of Science and Technology Research, 2(3), 127-131.

Yun, H. J., Jo, M.H., Jang, I. W., Lee, S.H., Ahn, S. H., Hur, H.J. (2012). Achieving high light efficiency and fast response time in fringe field switching mode using a liquid crystal with negative dielectric anisotropy. Journal of Liquid Crystals, 39, 1141-1148.

Ahmad, F., Jamil, M., Woo, L. J., & Jeon, Y. J. (2012). The investigation of molecular affinity involved in poly (ethylene glycol)-based polymer-dispersed liquid crystal display. Colloid and Polymer Science, 290(7), 599-606

Ahmad, F., Jamil, M., Lee, J. W., Ri, Y. H., & Jeon, Y. J. (2014). Characteristics of di-and tri-block copolymers: polymer disperse liquid crystal display. Journal of Modern Optics, 61(12), 1027-1032.

Murai, H., & Gotoh, T. (1993). Stabilization of epoxy-based polymer-dispersed liquid crystal films by addition of excess hardener. Molecular Crystals and Liquid Crystals, 226(1), 13-23.

Ellahi, M., Liu, F., Song, P., Gao, Y., Cao, H., Rafique, M. Y., Khaskheli, M. A., Iqbal, M. Z., Yang, H. (2013). Influence of the multi-functional epoxy monomers structure on the electro-opticalproperties and morphology of polymer-dispersed liquid crystal films, Journal of Polymer Bulletin,70 (11), 2967-2980.

Ellahi, M., Liu, F., Song, P., Gao, Y., Rafique, M. Y., Khan, D. F., Cao, H., Yang, H., (2014). Characterization and Morphology of Polymer-Dispersed Liquid Crystal Films. Journal of Soft Materials,12(3),339-345.

Sarkar, M. D., Gill, N. L., Whitehead, J. B., & Crawford, G. P. (2003). Effect of monomer functionality on the morphology and performance of the holographic transmission gratings recorded on polymer dispersed liquid crystals. Macromolecules, 36(3), 630-638.

Song, P., Yu, L., Cao, H., Wang, F., Liu, F., Zhang, C., Yang, H. (2012). Studies on electro-optical properties of polymer dispersed liquid crystal films based on epoxy resins prepared by UV-initiated cationic polymerisation. Liquid Crystals, 39(3), 313-321.

Song, P., Cao, H., Wang, F., Liu, F., Wang, J., Ellahi, M., Yang, H. (2012). The UV polymerisation temperature dependence of polymer-dispersed liquid crystals based on epoxies/acrylates hybrid polymer matrix components. Liquid Crystals, 39(9), 1131-1140.

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