Modified polymer surface analysis limitations

Most plastic products contain additives or other components, whose purpose is to modify the properties of the base resin, change its appearance, or lower the cost. Blends of more than one polymer are common, and composites contain inorganic fillers. Additives are incorporated into polymers for many reasons, such as altering transition temperatures, improving stability, or enhancing surface properties. NMR is very useful for characterizing the composition of blends, and solid-state techniques provide insight into compatibility and phase structure. Since NMR s sensitivity is limited, its utility for filler and additive analysis is limited, as they are often used at very low (pg/g) levels. In specific cases, however, NMR can be useful even for these components. 

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