反相气相色谱法测定高密度聚乙烯溶解度参数

摘要

采用反相气相色谱(IGC)技术测定了高密度聚乙烯(HDPE)在303.15～343.15 K温度范围内的溶解度参数(δ2)及相关指标.以正己烷(n-C6)、正庚烷(n-C7)、正辛烷(n-C8)、正壬烷(n-C9)、三氯甲烷(CHCl3)及乙酸乙酯(EtAc)作为探针分子溶剂,经计算获得了探针溶剂的比保留体积(V0g)、摩尔吸收焓(ΔHS1)、无限稀释摩尔混合焓(ΔH∞l)、摩尔蒸发焓(ΔHv)、无限稀释活度系数(Ω∞1)以及探针溶剂与HDPE的Flory-Huggins相互作用参数(χ∞1,2)等指标.结果表明,上述6种探针溶剂在测定温度范围内均为HDPE的不良溶剂.此外,还推导出了HDPE在室温(298.15 K)下的溶解度参数δ2为19.00 (J/cm3)0.5.%Inverse gas chromatographic ( IGC ) technology was used to determine the solubility parameters of high density polyethylene ( HDPE ) at the absolute temperatures from 303. 15 to 343. 15 K. Six solvents were applied as test probes including hexane ( n-C6), heptane ( n-C7 ), octane ( n-C8 ), nonane ( n-C9), chloroform ( CHCl3) and ethyl acetate ( EtAc ). Some thermo-dynamic parameters were obtained by IGC data analysis such as the specific retention volumes of the solvents (Vg0), the molar enthalpy of sorption ( △H0s), the partial molar enthalpy of mix-ing at infinite dilution ( △H1∞ ), the molar enthalpy of vaporization ( △Hv), the activity coeffi-cients at infinite dilution ( Ω1∞ ), and Flow-Huggins interaction parameters (x1∞,2) between HDPE and probe solvents. The results showed that the above six probes are poor solvents for HDPE. The solubility parameter of HDPE at room temperature ( 298. 15 K) was also derived as 19. 00 (J/cm3)05.