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It was determined that the thermal stability of poly(4-methyl-1-pentene) (P4MP) was maintained up to 424 C in an inert atmosphere by thermogravimetric analysis. The retention diagrams of ethyl acetate, tert-butyl acetate, and benzene on P4MP were plotted at temperatures between 30 and 280 C by inverse gas chromatography (IGC) technique. Melting temperature of the polymer was determined as 230 and 239.5C by IGC and differential scanning calorimetry (DSC), respectively. The percent crystallinity of P4MP was obtained from the retention diagrams at temperatures below melting point. , and effective exchange energy parameter, X eff of octane, nonane, decane, undecane, dodecane, tridecane, n-butyl acetate, isobutyl acetate, isoamyl acetate with P4MP, were determined between 240 and 280 C by IGC.

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The synthesis, characterisation and mesomorphic properties of a new chiral liquid crystal, (S)-5-(10-undecenyloxy)-2- [[[4-(2-methylbutoxy)phenyl]imino]methyl]phenol (UMBPIMP) are described. The phase transition temperatures of this mesogenic compound have been investigated by optical polarising microscopy, differential scanning calorimetry and inverse gas chromatography. The thermodynamics of UMBPIMP were investigated in order to understand its selectivity as a stationary phase in gas chromatography. Its liquid crystal selectivity was tested using the isomers nbutyl acetate, tert-butyl acetate and iso-butyl acetate, and the isomers n-butyl alcohol, tert-butyl alcohol and iso-butyl alcohol, as model chromatographic probes. The retention diagrams of the isomers were plotted between 30 C and 110 C using inverse gas chromatography. Using the specific retention volume, V 0 g , parameters such as the Flory-Huggins polymer-solvent interaction, w 1 12 , and hard-core polymer-solvent interaction, w à 12 , and exchange parameters such as effective energy, X eff , enthalpy, X 12 and entropy, Q 12 , were determined for the solvents chosen.

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