Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5190734 | Polymer | 2005 | 9 Pages |
Abstract
When the poly(acrylic acid) (PAA) gel-1,8-diazabicyclo-[5,4,0]-7-undecene salt (DAA) was placed in N-methyl-2-pyrrolidone containing an excess of alkylamine and triphenylphosphine, selective amidation took place from the outside to give the corresponding poly(N-alkylacrylamide) gel containing a C3 alkyl chain through a DAA-poly(N-alkylacrylamide) type gel capsule consisting of a hydrophilic unreacted core part and an amidated shell layer. The amidation proceeded by a reaction mechanism similar to the unreacted-core model. Thermal properties of the resulting poly(N-alkylacrylamide) gels such as deswelling behavior and equilibrium swelling ratio in water as a function of temperature were measured. The release of methyl orange from a poly(N-alkylacrylamide) gel and the gel capsule was also examined. PAA-poly(N-alkylacrylamide) type gel capsules containing a PAA core part and thermosensitive poly(N-alkylacrylamide) shell layer, prepared by the neutralization of DAA-poly(N-alkylacrylamide) type gel capsules, showed on-off chemical release characteristics in response to stepwise temperature changes across the LCST.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Organic Chemistry
Authors
Takashi Iizawa, Yoshinobu Matsuura, Yukio Onohara,