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

被引：56

作者：

Mascia, S.

Patel, M. J.

Rough, S. L.

Martin, P. J.

Wilson, D. I.

机构：

[1] Univ Cambridge, Dept Chem Engn, Cambridge CB2 3RA, England

[2] Univ Oxford, Dept Engn Sci, Oxford OX1 3PJ, England

来源：

EUROPEAN JOURNAL OF PHARMACEUTICAL SCIENCES | 2006年 / 29卷 / 01期

基金：

英国工程与自然科学研究理事会;

关键词：

extrusion; conical-entry die; square-entry die; squeeze flow; dilation; dewatering; microcrystalline cellulose;

D O I：

10.1016/j.ejps.2006.04.011

中图分类号：

R9 [药学];

学科分类号：

1007 ;

摘要：

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. (c) 2006 Elsevier B.V. All rights reserved.

引用

页码：22 / 34

页数：13

共 27 条

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