کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1786211 1023409 2014 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Comparison of thermal and elastic properties of glassy racemic and enantiomorphic ibuprofen studied by Brillouin light scattering and modulated differential scanning calorimetry
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم فیزیک ماده چگال
پیش نمایش صفحه اول مقاله
Comparison of thermal and elastic properties of glassy racemic and enantiomorphic ibuprofen studied by Brillouin light scattering and modulated differential scanning calorimetry
چکیده انگلیسی


• We measure the elastic properties of racemic and enantiomorphic ibuprofens.
• The sound velocity is determined during the vitrification process.
• The fragility of racemic and enantiomorphic ibuprofens is determined.

The vitrification process of racemic RS- and enantiomorphic S-ibuprofen was studied by using Brillouin light scattering and modulated differential scanning calorimetry (DSC). The sound velocity and the attenuation coefficient of both compounds were determined for the first time in the glassy, supercooled liquid and liquid states. The sound velocity and the hypersonic damping were similar between the two ibuprofen pharmaceuticals over the whole investigated temperature range including glassy, supercooled liquid and liquid states. The thermal expansion coefficient of the RS-ibuprofen was smaller than that of the S-ibuprofen, which suggests that the intermolecular force of the former is slightly stronger than the latter. The thermal relaxation times derived from the modulated DSC were consistent with the dielectric relaxation times in both RS- and S-ibuprofens. The fragility index of S-ibuprofen just above the glass transition was determined to be 73, which was smaller compared to the value of RS-ibuprofen, 89. This difference in the fragility indicates that the decrease in the fragility of S-ibuprofen compared to the racemic one may improve its stability of the amorphous state below the glass transition temperature against crystallization.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Current Applied Physics - Volume 14, Issue 7, July 2014, Pages 965–969
نویسندگان
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