反气相色谱法测定苯乙烯-氧乙烯-苯乙烯三嵌段聚合物的表面能

 采用反气相色谱法测定了苯乙烯 氧乙烯 苯乙烯三嵌段聚合物 (PS PEO PS)的色散成分的表面能 (γsd) ,研究探讨了温度及嵌段聚合物链段结构组成对γsd 的影响 ,并确定了γsd 与温度的数学关系式。研究结果表明 :在 70℃～ 12 0℃范围内 ,PS PEO PS的表面能较低 ;随着PS PEO PS表面组成中氧乙烯 (EO)成分的增加 ,色散成分的γsd 增大 ,且对温度的变化极其敏感 :随温度的升高 ,γsd 急剧地呈线性下降。

Determination of Surface Energy of PS-PEO-PS Triblock Copolymers by Inverse Gas Chromatography

The surface energy(gamma sd) of the dispersive component of the triblock copolymers, poly(styrene)-poly (ethylene oxide)-poly(styrene)(PS-PEO-PS), was determined by using inverse gas chromatography(IGC). A series of linear alkanes were used to determine the free energy of adsorption (delta GCH2) of a CH2 group in a temperature range of 70 degrees C-120 degrees C, and gamma sd of PS-PEO-PS were calculated. The effects of the polymer composition and temperature on gamma sd values were discussed. IGC data indicated that gamma sd values of PS-PEO-PS were lower (gamma dPS-PEO-PS-1 = 16.99 mJ.m-2, gamma dPS-PEO-PS-2 = 17.98 mJ.m-2, 70 degrees C) than that of PEG (gamma dPEG = 21.74 mJ.m-2, 70 degrees C), and increased as the ethylene oxide content increased in PS-PEO-PS. The gamma sd was sensitive to temperature, decreased sharply with the increase of temperature. Linear relationships were obtained between the gamma sd and temperature (t, degree C), which were gamma dPE-PEO-PS-1 = 28.12-0.161t and gamma dPS-PEO-PS-2 = 28.23-0.148t.