Carbon-13 nuclear magnetic resonance determination of the sequence structure of styrene–butadiene copolymers

Abstract

Twenty-six peaks occurring in the ¹³C n.m.r. spectra of styrene–butadiene copolymers are assigned to the 16 diads that arise from the 4 individual repeating structural units; styrene, vinyl, cis-, and trans-buta-1,4-diene; diad populations are determined from deduced relationships with peak intensites and average block lengths are calculated for each unit individually and in pairs.