Graft copolymers of functionalized polyethylene having free carboxylic groups (PEox) and liquid-crystalline polyester SBH (derived from sebacic acid, 4,4＇-dihydroxybiphenyl and 4-hydroxybenzoic acid) prepared under various conditions were investigated by means of high-resolution solid-state C-13 nuclear magnetic resonance spectroscopy. Fractionation products of the graft copolymers and a mixture of PEox with SBH were also studied.