使用红外光谱仪测分子的特征官能团，由此对比分析是否参与反应。取少量样品用乙醇稀释后滴到以溴化钾压成的基片上，放置烘箱60℃，1h，而后进行红外光谱测试。通过两个表面活性剂的出峰对比，是否含有C=C双键，以此来进行选择反应物。

Infrared spectroscopy is used to measure the characteristic functional groups of molecules and compare and analyze whether they participate in the reaction. A small amount of sample was diluted with ethanol and dropped onto a substrate pressed with potassium bromide, placed in an oven at 60 °C for 1h, and then subjected to infrared spectroscopy testing. By comparing the peaks of the two surfactants, whether they contain C=C double bonds, the reactants are selected.