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An Approach to Classify Degradable Polymers

Published online by Cambridge University Press:  15 February 2011

F. v. Burkersroda  and
A. M. Goepferich
F. v. Burkersroda
Affiliation:
Dept. of Pharm. Technology, University of Regensburg, 93040 Regensburg, Germany
A. M. Goepferich
Affiliation:
Dept. of Pharm. Technology, University of Regensburg, 93040 Regensburg, Germany to whom correspondence should be addressed
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Abstract

Despite tremendous progress towards a better understanding of polymer erosion, degradable polymers could so far not be classified according to their erosion behavior. It was the goal of this study to close this gap and to find those parameters that determine how a polymer erodes. Therefore, a dimensionless erosionnumber ε was defined, that can be calculated from the velocity of polymer degradation and water diffusion in the polymer bulk. s indicates whether erosion is a surface phenomenon (surface erosion) or whether it affects the complete polymer bulk bulk erosion). ε is characteristic for a polymer type and depends on the diffusivity of water inside polymer matrix, on the molecular weight of a polymer, and the dimensions of an eroding polymer matrix. The proposed erosion theory shows that ‘surface erosion’ and ‘bulk erosion’ are two potential erosion pathways that are open to any degradable polymer.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 550: Symposium GG/HH/II – Biomedical Materials-Drug Delivery, Implants and Tissue Engr , 1998 , 17
Copyright
Copyright © Materials Research Society 1999

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