Premium
Control of release characteristics in pH‐sensitive poly(vinyl alcohol)/poly(acrylic acid) microcapsules containing chemically treated alumina core
Author(s) -
Yun Jumi,
Kim HyungIl
Publication year - 2009
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.31332
Subject(s) - acrylic acid , vinyl alcohol , polymer chemistry , polymerization , swelling , emulsion polymerization , nuclear chemistry , vitamin , emulsion , controlled release , chemistry , materials science , chemical engineering , copolymer , organic chemistry , polymer , biochemistry , composite material , nanotechnology , engineering
The pH‐sensitive poly(vinyl alcohol)/poly(acrylic acid) hydrogel microcapsules containing vitamin B 12 ‐loaded Al 2 O 3 core were prepared with a three‐step emulsion polymerization. Al 2 O 3 was chemically treated with HCl or NaOH solutions at room temperature for 24 h to modify the binding properties with vitamin B 12 . The colon‐targeted release characteristics of vitamin B 12 from the microcapsules were evaluated at different pHs. These microcapsules showed the faster and larger release of vitamin B 12 due to the high swelling of microcapsule shell as the pH was changed into more basic condition. However, these microcapsules showed the slower and less release of vitamin B 12 as the acid value of Al 2 O 3 increased due to the strong binding interaction between Al 2 O 3 core and vitamin B 12 even though the initial loading of vitamin B 12 was higher. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010