Motional Heterogeneity and Polymorphism of Bisphenol-A Diacetate

Article abstract of DOI:10.1002/mrc.1260310605

Two polymorphs of bisphenol-A diacetate <2,2-bis(p-acetoxyphenyl)propane> were characterized by solid-state (13)C cross-polarization magic-angle spinning NMR, X-ray powder diffraction and differential scanning calorimetric measurements.The structure of one polymorph was determined by single-crystal x-ray diffraction methods, and shown to have two molecules in the asymmetric unit.The two polymorphs show markedly different molecular mobilities, as reflected in variable-temperature solid-state NMR measurements, with one-polymorph exhibiting motional heterogeneity in the flipping of the phenylene rings.KEY WORDS: (13)C NMR; (13)C CP MAS; Motional heterogeneity; Polymorphism; Bisphenol-A diacetate