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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A calix [4]arene modified carbon paste electrode was used for trace determination of copper. The study of the preconcentration of copper as well as the other heavy metal ions at the modified electrode, with subsequent measurement by differential pulse anodic stripping voltammetry (DPASV), indicates the efficient open-circuit accumulation of the analytes onto the electrode. Many parameters such as the composition of the paste, pH, preconcentration time and stirring rate influence the response of the measurement. The procedure was optimized for copper determination. For a 10-minute preconcentration time at pH 6.5 -7.5, the detection limit (LOD) was 1.1 mg L À1. The optimized method was successfully applied to the determination of copper in tap water sample by means of standard addition procedure. The copper content of the sample was comparable with the result obtained with AAS method.

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