Liquid phase migration in the extrusion and squeezing of microcrystalline cellulose pastes

Salvatore Mascia; Milan Patel; Sarah Rough; Peter Martin; D. Ian Wilson

doi:10.1016/j.ejps.2006.04.011

Liquid phase migration in the extrusion and squeezing of microcrystalline cellulose pastes

Salvatore Mascia, Milan Patel, Sarah Rough, Peter Martin, D. Ian Wilson

Research output: Contribution to journal › Article › peer-review

60 Citations (Scopus)

Abstract

Extensive movement of the liquid phase relative to the solids in solid-liquid pastes during extrusion forming is an undesirable process phenomenon. The impact of formulation and flow pattern on liquid phase migration (LPM) during extrusion of model pharmaceutical pastes (40-50 wt% microcrystalline cellulose/water) has been investigated by ram extrusion through square-entry and 45 degrees conical-entry dies, and by lubricated squeeze flow (extensional flow). Threshold velocities for LPM were observed in both configurations. Squeeze flow testing showed that dilation during extension can cause LPM, while ram extrusion featured both dilation effects and drainage due to compaction. The threshold velocities observed in the two configurations agreed when presented as characteristic shear rates. The threshold velocity increased with paste solids content.

Original language	English
Pages (from-to)	22-34
Journal	European Journal of Pharmaceutical Sciences
Volume	29
Issue number	1
DOIs	https://doi.org/10.1016/j.ejps.2006.04.011
Publication status	Published - 2006
Externally published	Yes

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title = "Liquid phase migration in the extrusion and squeezing of microcrystalline cellulose pastes",

abstract = "Extensive movement of the liquid phase relative to the solids in solid-liquid pastes during extrusion forming is an undesirable process phenomenon. The impact of formulation and flow pattern on liquid phase migration (LPM) during extrusion of model pharmaceutical pastes (40-50 wt% microcrystalline cellulose/water) has been investigated by ram extrusion through square-entry and 45 degrees conical-entry dies, and by lubricated squeeze flow (extensional flow). Threshold velocities for LPM were observed in both configurations. Squeeze flow testing showed that dilation during extension can cause LPM, while ram extrusion featured both dilation effects and drainage due to compaction. The threshold velocities observed in the two configurations agreed when presented as characteristic shear rates. The threshold velocity increased with paste solids content.",

keywords = "extrusion , conical-entry die , square-entry die , squeeze flow , dilation , dewatering , microcrystalline cellulose",

author = "Salvatore Mascia and Milan Patel and Sarah Rough and Peter Martin and Wilson, {D. Ian}",

year = "2006",

doi = "10.1016/j.ejps.2006.04.011",

language = "English",

volume = "29",

pages = "22--34",

journal = "European Journal of Pharmaceutical Sciences",

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TY - JOUR

T1 - Liquid phase migration in the extrusion and squeezing of microcrystalline cellulose pastes

AU - Mascia, Salvatore

AU - Patel, Milan

AU - Rough, Sarah

AU - Martin, Peter

AU - Wilson, D. Ian

PY - 2006

Y1 - 2006

N2 - Extensive movement of the liquid phase relative to the solids in solid-liquid pastes during extrusion forming is an undesirable process phenomenon. The impact of formulation and flow pattern on liquid phase migration (LPM) during extrusion of model pharmaceutical pastes (40-50 wt% microcrystalline cellulose/water) has been investigated by ram extrusion through square-entry and 45 degrees conical-entry dies, and by lubricated squeeze flow (extensional flow). Threshold velocities for LPM were observed in both configurations. Squeeze flow testing showed that dilation during extension can cause LPM, while ram extrusion featured both dilation effects and drainage due to compaction. The threshold velocities observed in the two configurations agreed when presented as characteristic shear rates. The threshold velocity increased with paste solids content.

AB - Extensive movement of the liquid phase relative to the solids in solid-liquid pastes during extrusion forming is an undesirable process phenomenon. The impact of formulation and flow pattern on liquid phase migration (LPM) during extrusion of model pharmaceutical pastes (40-50 wt% microcrystalline cellulose/water) has been investigated by ram extrusion through square-entry and 45 degrees conical-entry dies, and by lubricated squeeze flow (extensional flow). Threshold velocities for LPM were observed in both configurations. Squeeze flow testing showed that dilation during extension can cause LPM, while ram extrusion featured both dilation effects and drainage due to compaction. The threshold velocities observed in the two configurations agreed when presented as characteristic shear rates. The threshold velocity increased with paste solids content.

KW - extrusion

KW - conical-entry die

KW - square-entry die

KW - squeeze flow

KW - dilation

KW - dewatering

KW - microcrystalline cellulose

U2 - 10.1016/j.ejps.2006.04.011

DO - 10.1016/j.ejps.2006.04.011

M3 - Article

SN - 0928-0987

VL - 29

SP - 22

EP - 34

JO - European Journal of Pharmaceutical Sciences

JF - European Journal of Pharmaceutical Sciences

IS - 1

ER -

Liquid phase migration in the extrusion and squeezing of microcrystalline cellulose pastes

Abstract

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