The microstructure analysis of poly(vinylidene chloride-co-vinyl acetate) was done using chemical shift modeling and 2D NMR spectroscopy. Chemical shift modeling was applied to analyze the compositional sensitive resonances of quaternary carbon of vinylidene chloride unit. Reactivity ratios determination was done from the diad and triad fractions. To resolve the complex H-1 and C-13 {H-1} NMR spectra of copolymers, 2D H-1/C-13 hetero-nuclear single quantum coherence (HSQC). H-1/H-1 total correlation spectroscopy (TOCSY) and hetero-nuclear multiple bond correlation (HMBC) experiments were conducted. The combination of 2D NMR experiments Supported by chemical shift modeling enabled to assign the complex and overlapping proton and carbon-13 resonances unambiguously. (c) 2005 Elsevier Ltd. All rights reserved.