Solid state nuclear magnetic resonance (NMR) is a powerful technique to analyze polymer composites. The use of proton relaxation data to evaluate the dispersity of the dispersion phase in the composite and its homogeneity are very wide. In this work PVC=silica composites were prepared using different ratios to obtain a new material to be used in chromatograph column for separation of plant extracts. Thus, this study used proton spin-lattice and spin-spin nuclear magnetic resonance relaxation data, determined in a low field NMR spectrometer as a method to characterize those composites in relation to silica dispersion as well as PVC= silica compatibility. From the relaxation data analyses, the best ratio of PVC= silica, according to the components dispersion and consequently composite compatibility, was 80=20, according to the determined T 1 values.