# Evidence: remixing of separated amorphous phases

Parent: — · class: phase behaviour · names merged here: phase remixing on heating; remixing of separated amorphous phases

2 papers measured or used it, 0 only mentioned it (of 207 kept papers). Papers in year order; each section heading ends with the paper's category / subcategory. Generated by tools/build_evidence.py from registry/concepts.csv and the cards; do not edit.

## 2010 Marsac — Effect of Temperature and Moisture on the Miscibility of Amorphous Dispersions of Felodipine and Poly(vinyl pyrrolidone) · Solid state stability / Physical stability

[2010-marsac-temperature-moisture-miscibility-felodipine-pvp-asd](../../../cards/2010-marsac-temperature-moisture-miscibility-felodipine-pvp-asd/paper.html) · Solid state stability / Physical stability · measured · as: remixing of separated amorphous phases

| id | kind | content | locator |
|---|---|---|---|
| R16 | record, measured | NH spectra during isothermal hold at 125 °C — 50% PVP film after about 4 h at 94% RH and 1 h dry-air purge; 0 to 1500 min (P13) — initial spectrum: main band ≈3340 cm−1, shoulder ≈3300 cm−1, weak band ≈3230 cm−1; with time the band near 3290–3297 cm−1 grows relative to the band near 3340–3345 cm−1, and the late spectra approach the never-exposed reference (maximum ≈3297 cm−1, band ≈3228 cm−1) (read from Fig. 11) | Fig. 11, p.178; text p.177 |
| R17 | record, measured | peak-height ratio h(3290)/h(3345) (E2) vs ln time at 125 °C — the R16 sample; reference line = never-exposed film of the same ratio — sub-table below | Fig. 12, p.178 |
| R18 | record, derived (relation named, not printed) | time to reach the maximum level of drug–polymer hydrogen bonding at 125 °C, by extrapolation of R17 — R16 sample — approximately 39 h; extrapolation method not printed (see X8) | p.178 |
| C21 | claim, conclusion, authors: "likely reflecting"; "probably indicating" | The shift of the thermal event to higher temperature with each DSC cycle reflects progressive remixing of the phase-separated system; the final exotherm followed by an endotherm reflects crystallization and melting [rests on: R15] | p.177 |
| C22 | claim, conclusion, authors: "indicating"; "indicates" | At 125 °C the growth of the 3290 relative to the 3345 cm−1 band shows drug–polymer hydrogen bonds re-forming as drug and polymer remix; the ratio approaches that of a never-exposed dispersion, and extrapolation gives the maximum level of drug–polymer hydrogen bonding after approximately 39 h [rests on: R16, R17, R18] | p.177, p.178 |
| C47 | claim, conclusion, authors: "supports the supposition" | At 125 °C, well above the Tg of felodipine and of the one-phase dispersion (about 80 °C), remixing takes place over several hours, which supports miscibility of amorphous felodipine and PVP in the absence of moisture [rests on: R16, R17, R21] | p.182 |

## 2017 Xie — Effect of Temperature and Moisture on the Physical Stability of Binary and Ternary Amorphous Solid Dispersions of Celecoxib · Solid state stability / Physical stability

[2017-xie-temperature-moisture-celecoxib-binary-ternary-asd-stability](../../../cards/2017-xie-temperature-moisture-celecoxib-binary-ternary-asd-stability/paper.html) · Solid state stability / Physical stability · used · as: phase remixing on heating

| id | kind | content | locator |
|---|---|---|---|
| C34 | claim, mechanism, authors: "A possible explanation" | The single Tg on reheating may arise because the separated CEX:PVP phases remixed during heating [rests on: R18; cited: ref 16] | p.7 |