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Development of hot-melt extrusion as a novel technique for the ...

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Fig. 4.1a: MTDSC <strong>the</strong>rmograms <strong>of</strong> pure PMOL (inset) and Eudragit EPO, Kollidon VA64Previous studies [33–34] <strong>of</strong> pure PMOL reported <strong>the</strong> existence <strong>of</strong> three crystal <strong>for</strong>ms, <strong>the</strong>Form III which is highly unstable (<strong>melt</strong>ing point at 148 o C), <strong>the</strong> met<strong>as</strong>table orthorhombic(Form II) with <strong>melt</strong>ing point at 160 o C and <strong>the</strong> stable monoclinic (Form I) with <strong>melt</strong>ing pointat 170 o C while <strong>the</strong> amorphous <strong>for</strong>m h<strong>as</strong> a gl<strong>as</strong>s transition at 23 o C. The polymorphic <strong>for</strong>m <strong>of</strong>PMOL that w<strong>as</strong> used in <strong>the</strong> current study w<strong>as</strong> <strong>the</strong> monoclinic Form I. The DSC scans <strong>of</strong> <strong>the</strong>PMOL/EPO extrudates (Fig. 4.1b) showed <strong>melt</strong>ing endo<strong>the</strong>rms at 143.3 o C, 148.5 o C and151.5 o C, respectively that correspond to 40, 50 and 60% PMOL loadings.Fig. 4.1b: MTDSC <strong>the</strong>rmograms <strong>of</strong> PMOL/EPO extrudates at different PMOL loadings.70 | P a g e

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