Detail of "2424-01-3"

Reference

Synthesis, Characterization, and Aqueous Solution Behavior of Electrolyte- and pH-Responsive Carboxybetaine-Containing Cyclocopolymers

Synthesis, Characterization, and Aqueous Solution Behavior of Electrolyte- and pH-Responsive Carboxybetaine-Containing Cyclocopolymers. Thomas, David B.; Vasilieva, Yulia A.; Armentrout, R. Scott; McCormick, Charles L. (Department of Polymer Science, University of Southern Mississippi, Hattiesburg, MS 39406-0076, USA). Macromolecules, 36(26), 9710-9715 (English) 2003 American Chemical Society. CODEN: MAMOBX. ISSN: 0024-9297. DOCUMENT TYPE: Journal CA Section: 35 (Chemistry of Synthetic High Polymers) A novel pH- and salt-responsive carboxybetaine monomer, 4-(N,N-diallyl-N-methylammonio)butanoate (2), was prepd. and cyclocopolymd. with the cationic monomer N,N-diallyl-N,N-dimethylammonium chloride (3) in 0.5 M NaCl aq.Chemicals with cas numbers 2424-01-3 and 258843-07-1 also play role. soln. (pH = 7.0) using 2-hydroxy-1-[4-(hydroxyethoxy)phenyl]-2-methyl-1-propanone (Irgacure 2959) as the free-radical photoinitiator. The molar feed ratio of 2:3 was varied from to 0:100 with the total monomer concn. held const. at 2.5 M. Cyclopolymn. to five-membered ring structures common to diallylammonium salts was confirmed by 13C NMR spectroscopy. Reactivity ratio studies indicate that 2 and 3 copolymerize in a nearly ideal fashion (r1 = 0.86, r2 = 0.99). Wt.-av. mol. wts. and second virial coeffs. vary from (6.0 to 12.8) ′ 104 g mol-1 and (1.62 to 5.36) ′ 10-4 mL mol g-2, resp. Dil. soln. viscosity behavior depends on copolymer compn., ionic strength, and pH. Copolymers with a large excess charge exhibit typical polyelectrolyte behavior, while those with balanced charge exhibit "anti-polyelectrolyte" behavior reported for zwitterionic (co)polymers. The polymers studied here are closely analogous cyclocopolymers we previously reported contg. sulfobetaine mer units.25 Unlike solns. of sulfobetaine-contg. polymers, solns. of poly(2-co-3) remain sol. at very low ionic strength even up to 100% incorporation of 2. Addnl., while the sulfobetaine systems are insensitive to pH, solns. of poly(2-co-3) exhibit a pH-dependent viscosity. All the copolymers have an apparent pKa of ~3.6. Copolymers with 2 incorporations of 28 mol % and above have viscosity responsiveness between pH values of 2.5 and 4.5. The max. pH response was achieved for solns. of poly(2-co-3) contg. 37 and 56 mol % of the carboxybetaine monomer 2. .