RAMAN-SPECTROSCOPIC CHARACTERIZATION OF MICROSTRUCTURE OF POLYBUTADIENES DURING HYDROGENATION AND HYDROBROMINATION REACTIONS

The microstructures of hydrogenated polybutadienes produced using diff erent hydrogenation routes, namely the low-temperature hydrogenation u sing tris(triphenylphosphine)rhodium(I) chloride or platinum black cat alysts, have been studied by Raman spectroscopy. The same spectroscopi c method has also been used to examine the products formed by a hydrob romination reaction. The selectivity of these methods towards the vari ous microstructural units has been quantitatively examined from observ ation of the nu(C=C) stretching vibrations of the cis-1,4, trans-1,4 a nd vinyl-1,2 components in the polymer. The isolation and spectroscopi c characterization of an intermediate formed during the hydrogenation of polybutadienes using tris(triphenylphosphine)rhodium(i) chloride is also reported.