| Abstract
| - Ordered structures in samples of Bisphenol A polycarbonate (BPAPC) prepared by varyingthermal and solvent conditions were investigated by infrared and Raman spectroscopy, wide-angle X-rayscattering (WAXS), and differential scanning calorimetry (DSC). Based on the spectroscopic analysisand ab initio quantum mechanical calculations of diphenyl carbonate as a model compound, an assignmentof the bands conformationally sensitive to the trans−trans and cis−trans structures is proposed.Temperature dependences of the vibrational spectra of BPAPC show that cis−trans structure is theenergetically preferred conformation in the amorphous state and in solution and its population can beincreased with decreasing temperature in amorphous BPAPC even below the glass transition temperature.Differences in the degrees of ordering in semicrystalline BPAPC assessed from the vibrational spectra,WAXS, and DSC indicate partial order in the interfacial region between the crystalline and amorphousphases. In some solvents (toluene, benzene), aggregation of BPAPC occurs, leading to the ordered structureanalogous to crystalline BPAPC. The order is preserved in semicrystalline BPAPC obtained by the room-temperature evaporation of the solvent.
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