Polymer-polymer miscibility determination via CP-MAS NMR in blends of deuteriated and protonated polymers

Intermolecular cross polarization is further applied to high molecular weight polymer--polymer blends such as polystyrene (PS) and polyvinyl (PVME) blends to obtain useful information about miscibility at the molecular level and to show that the method is applicable to blends in which one component polymer is present in small quantities ( < 5-10%). Miscibility information can also be obtained from relaxation times of the blend of the component polymers, such as polymethyl methacrylate (PMMA) and polyvinyl chloride (PVC), have very different relaxation times. However, proton-relaxation experiments are of little value if the component polymers have similar characteristic relaxation times or if the sample contains low volume fractions of either component.--K.L.B.