反气相色谱法研究聚己烯-1与不同溶剂的热力学相互作用

Using Inverse Gas Chromatography to Study Thermodynamic Interactions Between Polyhexene-1 and Solvents

用反相气相色谱法测定了聚己烯－１与８种溶剂的Ｆｌｏｒｙ－Ｈｕｇｇｉｎｓ相互作用参数Ｘ１和聚乙烯－１的溶解度参数，确定了Ｘ１与温度的数学关系式：Ｘ１＝０．９２３－２５６．４／Ｔ。测定结果表明聚己烯－１溶于正辛烷是一个放热过程，而且Ｘ１随着溶剂中碳数的增加而减小。同时也根据Ｘ１值和溶剂的溶解度参数δ１计算出了聚己烯－１的溶解度参数δ，其值为２７．５０（Ｊ／ｍＬ）１／２。

Long chaina-olefins polymer is a kind of comb-like polymer with special properties, which is widely usedas additives in crude oil and it's products. The structure and solution properties of the polyhexene-1 have beenreported in literature, but few report on its thermodynamic interaction with solvents and it's solubility parameter. Inthis paper, the thermodynamic interactions of polyhexene-1 tvith eight solvents have been studied by using inversegas chromatography. The eight Flory-Huggins interaction parameters X1 were calculated, results indicate that X1decrease with increase of the carbon number of linear alkane, but when the carbon number is larger than 8, X1tends to increase with the carbon number. It was also shown that the interaction of polyhexene-1 with cyclohexane isthe strongest among all the studied solvents, and that with n-octane is the strongest among the linear alkanes. Therelation of interaction parameter (polyhexene/n-octane) with temperature T was also detendned: X1 = 0. 852 -229. 09/ T. It was shown that the dissolution of polyhexene-1 in n-octane is an exothermic process with an enthalpychange of - 4. 84kJ. mol - 1. The solubility parameter δ2 of polyhexene-1 is 27. 5 (J/moL) 1/2, determined from theinteraction parameters X1.