The Infrared Spectra of Commonly Used Diene Rubbers

2 The Infrared Spectra of Commonly Used Diene Rubbers 

All diene rubbers may have few isomers depending on the addition of diene monomers. 

Butadiene rubber (BR) is the simplest case with R = H. It shows strong bands at 1625, 1643 and 1666 cm 1 for C=C stretching (n), for pendent -CH=CH2 (vinyl), cis 1, 4 BR and trans 1,4 BR, respectively. It also shows characteristic peaks at 967, 910 and 740-732 cm-1 associated with wagging of the vinylic C-H bonds for trans 1,4, pendent and cis 1,4 double bonds, respectively [11]. 

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