气相色谱法研究聚辛烯-1与不同溶剂的热力学相互作用

Study on Thermodynamic Interactions Between Polyoctene 1 and Solvents Using Gas Chromatography

用气相色谱法测定了聚辛烯－１与８种溶剂的Ｆｌｏｒｙ－Ｈｕｇｇｉｎｓ相互作用参数χ１和聚辛烯－１的溶解度参数，确定了χ１与温度的数学关系式。测定结果表明聚辛烯－１溶于正辛烷是一个放热过程。

Polymer of long chain α 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 χ 1 were calculated. The results indicated that χ 1 decreases with increase of the carbon number of linear alkane, but when the carbon number is larger than 8, χ 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:χ 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 δ 2 of polyoctene 1 is 27.42 (J/mL) 1/2 , determined from the interaction parameters χ 1.