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[Study on thermodynamic interactions between polyoctene-1 and solvents using gas chromatography].

Abstract

Polymer of long chain alpha-olefins is a kind of comb-like polymer with special properties. In this paper, the thermodynamic interactions of polyoctene-1 with eight solvents have been studied by using gas chromatography. The eight Flory-Huggins interaction parameters chi 1 were calculated. The results indicated that chi 1 decreases with increase of the carbon number of linear alkane, but when the carbon number is larger than 8, chi 1 tends to increase with the carbon number. It was also shown that the interaction of polyoctene-1 with cyclohexane is the strongest among all the studied solvents, and that with n-octane is the strongest among the linear alkanes. The relation of interaction parameter (polyoctene-1/n-octane) with temperature T was also determined: chi 1 = 1.697-523.1/T. It was shown that the dissolution of polyoctene-1 in n-octane is an exothermic process with an enthalpy change of -4.84 kJ/mol. The solubility parameter delta 2 of polyoctene-1 is 27.42 (J/mL)1/2, determined from the interaction parameters chi 1.

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BibTeXRIS

Y Zhang, L Feng, Z Fan. 1999. [Study on thermodynamic interactions between polyoctene-1 and solvents using gas chromatography].. https://pubmed.ncbi.nlm.nih.gov/12548823/

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