Qualitative FT-Raman investigation of the ring opening metathesis polymerization of dicyclopentadiene

This study describes the qualitative analysis of the polymerization reaction of DCPD (DiCycloPentaDiene) and its reaction products. The polymerization was carried out using WCl6/Si(allyl)4 (1), first generation Grubbs’ (2) and second generation Grubbs’ (3) catalysts. When system 1 was used as a catalyst, solution concentration determined whether soluble or insoluble polymer was obtained. When Grubbs’ catalysts were employed, insoluble polymer was formed in all cases. The ring opening metathesis polymerization (ROMP)-reaction and the resulting polymers were monitored in situ via FT-Raman-spectroscopy. Using FT-Raman-spectroscopy, the stereospecific nature of the forming polymer can be determined during the polymerization reaction. The obtained spectra illustrate that the linear polymer has a prevailing cis double bond configuration, while the polymer formed using the 1e generation Grubbs catalyst has a predominant trans double bond configuration. The second generation Grubbs catalyst exhibits a poor stereoselectivity. These results are in accordance to literature data where the stereospecific nature of these polymers where determined using NMR-spectroscopy.

Graphical abstractThe qualitative analysis of the catalytic ring opening metathesis polymerization reaction of dicyclopentadiene (DCPD) and its resulting polymers by means of FT-Raman spectroscopy is described. The polymerization was conducted using WCl6/Si(allyl)4 (1), Grubbs’ first (2) and second (3) generation catalysts. It was found that 1 has a prevailing cis selectivity while 2 has a predominant trans-selectivity. Catalyst 3 exhibits a poor stereoselectivity. Figure optionsDownload full-size imageDownload as PowerPoint slide