4-[4-(2-Etilhekziloksi)benzoiloksi]benzoik asid Sıvı Kristalinin Bazı Çözücülerle Termodinamik Etkileşimleri

Abstract

Bu çalışmada 4-[4-(2-Etilhekziloksi)benzoiloksi]benzoik asid’in n-alkanlar ile termodinamik etkileşimleri ters gaz kromatografi metoduyla incelendi. Çözücülerin alıkonma hacimlerinden, 170oC-195oC sıcaklık aralığında, sonsuz seyreltiklikteki ağırlık kesri aktivite katsayısı, Ω1∞, Flory-Hugginsve hal denklemi etkileşim parametreleri ((X12∞ ve X12*), etkin değişim enerji parametresi X12-, kısmi molar sorpsiyon ısısı, ΔHs-, kısmi molar karışma ısısı, ΔH1∞-, molar buharlaşma ısısı, ΔHv- gibi termodinamik etkileşim parametreleri hesaplandı.

Keywords

• Ters gaz kromatografisi, termodinamik, sıvı kristaller

Thermodynamical Interactions of 4-[4-(2- Ethylhexyloxy)benzoyloxy] benzoic acid Liquid Crystals with Some Solvents

Abstract

In this study, thermodynamic interactions of 4-[4-(2-Ethylhexyloxy)benzoyloxy] benzoic acid liquid crystal with n-alkane were examined by inverse gas chromatography method. From the retention volumes, it was calculated some thermodynamic interaction parameters such as the weight fraction activity coefficient of the solvents at infinite dilution, Ω1∞, Flory-Huggins and hard core polymer-solvent interaction parameters, (X12∞ and X12*), effective exchange energy parameter,X12- the partial molar heat of sorption, ΔHs- the partial molar heat of mixing, ΔH1∞- and molar heat of vaporization, ΔHv- at temperature range between 170 oC and 195oC

Keywords

• Inverse gas chromatography, thermodynamics, liquid crystals

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