The Synthesis Of Styrene Dimer And Its Temperature-Dependent Infrared Spectroscopy

In order to investigate the change of polymer structure, Fourier Transforminfrared spectroscopy(FTIR) is widely applied for its high sensitivity. It can also beused to study the glass transition behavior of the polymer system. The configurationand conformation of polystyrene (PS) are very complex and hard to be confirmed, soa simplified model of polystyrene, especially styrene dimer is needed for auxiliarystudy.In this paper, styrene dimer was generated via Wurtz coupling reaction andKumada coupling reaction and then the product was extracted by vacuum distillationand column chromatography. The structures and properties were characterized viaMass Spectrometry (MS), Gas Chromatography (GC) and Nuclear MagneticResonance (NMR).1,4-diphenylbutane was successfully synthesized by Wurtz coupling reactionwith two different catalytic systems. We changed the time and temperature, andanalyzed the effect and GC yield. When the reaction time and temperature was16hours and25℃, the results showed that the product with β-bromine ethyl benzeneacted as raw material had the highest GC yield. FTIR was used to verify the productand the assignments of infrared peaks were analyzed. It was confirmed that1,4-diphenylbutane can be used as PS model molecule. We also found several changesof1,4-diphenylbutane at various temperatures by analyzing its infrared spectra.1,3-diphenylbutane was successfully synthesized by Kumada cross couplingreaction. We also compared the effect and GC yield of experiments using twodifferent catalytic systems. Two different catalytic systems were used in theexperiment and the results suggested that the experiment withFe(acac)3/TMEDA/HMTA performed better.