Synthesis and gelation of novel fluoroalkyl end‐capped N‐(1,1‐dimethyl‐3‐oxobutyl)acrylamide copolymers containing triol segments—Interaction of these fluorinated gels with various hydrophilic compounds

Abstract Fluoroalkyl end‐capped N ‐(1,1‐dimethyl‐3‐oxobutyl)acrylamide (DOBAA) copolymers containing triol segments were prepared by the reactions of fluoroalkanoyl peroxide with the corresponding monomer and N ‐tris(hydroxymethyl)methylacrylamide (NAT). These obtained fluorinated copolymers [R F ‐(DOBAA) x ‐(NAT) y ‐R F ] were found to cause gelation in water, dimethyl sulfoxide, and N , N ‐dimethylformamide under the non‐crosslinked conditions, although the corresponding nonfluorinated DOBAA–NAT copolymer [‐(DOBAA) x ‐(NAT) y ‐] could cause no gelation in these solvents. This gelation is governed by the synergistic interaction of strong aggregations of end‐capped fluoroalkyl segments and intermolecular hydrogen bonding between triol segments. We also studied the uptake and release of a variety of hydrophilic compounds such as methylene blue, methyl orange, 4‐hydroxyazobenzene‐4′‐sulfonic acid sodium salt, 2,4‐dihydroxyazobenzene‐4′‐sulfonic acid sodium salt, acriflavine hydrochloride, acridine hydrochloride, lucigenin, and fluorescein by this fluorinated copolymer gel and fluoroalkyl end‐capped NAT homopolymer gel [R F ‐(NAT) n ‐RF] for comparison. It was demonstrated that the uptake and release ratios of these hydrophilic compounds by R F ‐(DOBAA) x ‐(NAT) y ‐R F gel become generally lower than those of R F ‐(NAT) n ‐R F gel. Interestingly, R F ‐(DOBAA) x ‐(NAT) y ‐R F gel has no releasing power toward methylene blue, acridine hydrochloride, lucigenin, and fluorescein, although R F ‐(NAT) n ‐R F gel has a good releasing power toward these compounds. Additionally, R F ‐(DOBAA) x ‐(NAT) y ‐R F gel was applied to the controlled release of anticancer drugs such as methotrexate (MTX), and the releasing ratios of MTX became higher with increasing pH values (from pH 4.3 to 9.1). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88:3212–3217, 2003