Faculty of Science

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https://ir.lib.pdn.ac.lk/handle/20.500.14444/213

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Browsing Faculty of Science by Author "Abeyrathne, A. R. N. M."

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    Liquid Crystal Behavior of three Novel Glycosides
    (2012) Abeyrathne, A. R. N. M.; Perera, A. D. L. Chandani; Karunaratne, D. N.
    Novel glycosides synthesized by linking D-glucose to three different non-polar aglycones parts: cinnamyl alcohol, chloroxylenol and 3-pentadecylphenol show both thermotropic and lyotropic liquid crystal phases. The effect of inclusion of a rigid spacer in between hydrophilic and hydrophobic parts on the stability of liquid crystal phases is investigated. Both acetylated and deacetylated compounds exhibit thermotropic and lyotropic liquid crystal behaviour. The liquid crystal phases were confirmed as Smectic A, Smectic B and hexagonal columnar by X-ray studies
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    Surfactant Behaviour of Novel Carbohydrate Liquid Crystals
    (Postgraduate Institute of Science, University of Peradeniya,, 2013) Abeyrathne, A. R. N. M.; Karunaratne, D. N.; Perera, A. D. L. Chandani
    The study of liquid crystalline behavior of new amphiphilic carbohydrate derived liquid crystals has gained world-wide interest since these glycolipids have technical and biological applications in a wide area such as thermotropic and lyotropic liquid crystals, surfactants, lubricants, solubilization and crystallization of membrane enzymes etc. Glycolipids are natural surfactants based on a hydrophilic sugar (carbohydrate) part and a hydrophobic hydrocarbon domain. In this paper, surfactant behavior of five novel glycolipids is presented based on their Critical Micelle Concentration (CMC). The nonionic surfactants treated with iodine form donor –acceptor complexes in aqueous medium. Thus the CMC is determined by the spectral absorption and the shift in the absorbance maximum (λmax) of I 2 upon complex formation with surfactant. For a better comparison of results, turbidity measurements are exploited to determine CMC. In accordance with the results of both methods, the CMC of all the acetylated compounds, lie within the typical range for nonionic surfactants; 10 -5 – 10 -4 mol dm-3 . Further, other fundamental parameters of surfactants, such as the HLB values and the cloud points of each compound were also studied.