PMSE 168 |
| Amphoteric hydrogel hollow capsules were produced by chemical cross-linking of hydrogen-bonded poly(methacrylic acid) (PMAA)/polyvinylpyrrolidone capsules deposited onto silica core with ethylenediamine followed by core dissolution. Highly swellable at acidic and basic pH due to excess positive and negative charge in the capsule wall, capsules showed minimum size at pH 5.5. Capsule swelling can be controlled through variation of cross-linking time and ionic strength. We contrast the swelling and permeability of capsules whose wall contains LbL-deposited and chemically cross-linked hydrogen bonded polymers in pH range from 2 to 10, when such capsules transit from hydrogen-bonded cross-linked multilayers to highly swollen hydrogels with no intermolecular association. We compare their properties with those found for hollow capsules composed of PMAA hydrogel. These capsules have potential for applications in biomaterials and biotechnology. |
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Polymers for Biomedical Applications
8:30 AM-12:10 PM, Tuesday, 12 September 2006 San Francisco Marriott -- Salon B1, Oral
Division of Polymeric Materials: Science & Engineering |