# Evidence: polymer swelling

Parent: — · class: transport and absorption · names merged here: polymer swelling; swelling

3 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.

## 2018 Bhardwaj — Surface area normalized dissolution to study differences in itraconazole-copovidone solid dispersions prepared by spray-drying and hot melt extrusion · Dissolution / A. Release mechanism and LoC

[2018-bhardwaj-surface-area-normalized-dissolution-itraconazole-pvpva-asd](../../../cards/2018-bhardwaj-surface-area-normalized-dissolution-itraconazole-pvpva-asd/paper.html) · Dissolution / A. Release mechanism and LoC · used · as: polymer swelling

| id | kind | content | locator |
|---|---|---|---|
| C20 | claim, mechanism, authors: "might" | The deviation of the 10% drug release from linearity (lower R²) might come from initial hydration and swelling of the polymer [rests on: R4.i-j] | p.12 |

## 2023 Deac — Dissolution Mechanisms of Amorphous Solid Dispersions: A Close Look at the Dissolution Interface · Dissolution / A. Release mechanism and LoC

[2023-deac-asd-dissolution-interface](../../../cards/2023-deac-asd-dissolution-interface/paper.html) · Dissolution / A. Release mechanism and LoC · used · as: swelling

| id | kind | content | locator |
|---|---|---|---|
| C42 | claim, prior hypothesis, authors: asserted | Linear, nonionic, glassy polymers above the entanglement molecular weight, such as PVPVA, dissolve through a rubbery gel layer: solvent plasticizes the glass at the glass/gel interface; entangled chains there diffuse slowly while segments are mobile; the gel grows and swells as solvent enters and its viscosity falls; at a critical solvent concentration the chains disentangle and leave at the gel/solution interface [rests on: cited: refs 30-38] | p.2227-2228 |
| C58 | claim, mechanism, authors: asserted ("accounting for") | The pores are first filled with hydrophilic phase through which water enters, so drug and polymer in that phase can release, accounting for some release just above the LoC; water entering through the pores moves the glass/gel boundary deeper and the gel grows, as for 50% DL MePHPH and 20% DL PHPH, whose 30 min gels were thicker than those of neat PVPVA and congruent ASDs and still growing [rests on: R4.f, R4.i, R1.f, R1.g] | p.2231 |
| C60 | claim, mechanism, authors: "appeared"; "A possible explanation"; "corroborating" | At 40% DL release stayed good (marginally faster than neat PVPVA) although continuous hydrophobic regions formed at times; this network was weaker than at 50% DL and intermittently ruptured, possibly because swelling pressure from water penetration overcame its strength; only parts of the surface were continuous (Fig. 11h) [rests on: R1.d, R1.e, R4.e, R6.d, R9.b] | p.2231 |

## 2024 Deac — Dissolution mechanisms of amorphous solid dispersions: Role of polymer molecular weight and identification of a new failure mode · Dissolution / A. Release mechanism and LoC

[2024-deac-asd-polymer-molecular-weight-failure-mode-loc](../../../cards/2024-deac-asd-polymer-molecular-weight-failure-mode-loc/paper.html) · Dissolution / A. Release mechanism and LoC · used · as: polymer swelling

| id | kind | content | locator |
|---|---|---|---|
| C46 | claim, mechanism, authors: "is expected to"; conclusion: "suggest" | Entangled polymers swell more and give a thicker gel layer; swelling is expected to increase the distance between droplets, so that when the diluted chains finally disentangle the droplets are far enough apart not to agglomerate at once [rests on: cited: ref 24; argument only] | p.10 |