Hydrophobically Modified Poly(sodium 2-acrylamido-2-methylpropanesulfonate)s Bearing Octadecyl Groups:  A Fluorescence Study of Their Solution Properties in Water

Abstract

Fluorescently labeled amphiphilic polyelectrolytes have been prepared by free-radical copolymerization in dimethylformamide using azobis(isobutyronitrile) as the initiator of sodium 2-acrylamido-2-methylpropanesulfonate (AMPS) and (1) N- [4-(1-pyrenyl)butyl]-N-n-octadecylacrylamide (PyODA) in 98:2 and 95:5 molar ratios, (2) N- [2-(1-naphthyl)ethyl]-N-n-octadecylacrylamide (NpODA) in 98:2 and 95:5 molar ratios, and (3) a mixture of the two labeled monomers in a molar ratio of 95:4:1 (AMPS: NpODA:PyODA). The solution properties of the copolymers in water and in salt solutions have been studied by viscometry, 1 H NMR spectroscopy, and fluorescence spectroscopy. Evidence from nonradiative energy transfer between excited naphthalene (Np*) and pyrene (Py) in aqueous solutions of the doubly labeled polymers points to the formation of polymeric micelles. The inefficiency of nonradiative energy transfer between Np* and Py in mixed solutions of the singly labeled polymers indicates that the micelles are mostly unimolecular. The quenching of fluorescence of polymer-linked pyrene by nitromethane and thallium nitrate has been used to assess the accessibility of the chromophore to neutral molecules and to cationic species, respectively, in water and in solutions of increasing ionic strength. The results are discussed in light of previous studies of the properties in solution of neutral polymers carrying the same hydrophobic substituents as PAMPS-Py(Np)ODA and of amphiphilic PAMPS substituted with various other hydrophobic groups.

Rheological Properties of Mixtures of Oppositely Charged Polyelectrolytes. A Study of the Interactions between a Cationic Cellulose Ether and a Hydrophobically Modified Poly[sodium 2-(acrylamido)-2-methylpropanesulfonate]

“…12 The polyanions PAMPS and PAMPS-Dod were prepared as described earlier. 13,14 PAMPS-Dod is a copolymer of sodium 2-(acrylamido)-2-methylpropanesulfonate (AMPS) and N-n-dodecylmethacrylamide (Dod) with a dodecyl content of 5 mol%. The molecular weight of PAMPS-Dod was determined to be approximately 5×10 4 Dalton by size exclusion chromatography (SEC) on a JASCO GPC-900 system equipped with Shodex Asahipak GF-7 M HQ columns using a 0.2 M solution of LiClO 4 in methanol as the eluent and was calibrated with poly(ethylene glycol) standards (Scientific Polymer Products, Inc.).…”

Synthesis and association properties in water solution of random copolymers of 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid and isodecyl methacrylate—potential application as surfactants in micellar‐enhanced ultrafiltration processes

“…2 Morishima and coworkers prepared random copolymers of 2-acrylamido-2-methylpropane sulfonic acid (AMPS) with fluorescently labeled acrylamide comonomers, and their solution properties in water were studied. 3,4 Also, other authors have prepared random copolymers of AMPS with hydrophobic monomers. 5 The association behavior of different random copolymers of AMPS was clearly dependent on structural differences of the hydrophobic side chains.…”

Red‐Emitting Polymer Microspheres Containing Zinc Porphyrins

“…[19][20][21][22][23][24][25][26] Moreover, Table 2. Solubility of ZnAOTPP, NVP, and PVP in different solvents.…”

“…In solution, the polymer can self-assemble to form micelle-like assemblies in the presence of a selective solvent that is incompatible with parts of the polymer chains. [19][20][21][22][23][24][25][26] Moreover, the polymer assemblies can be controlled by a force balance involving compatibility of soluble parts with solvent and incompatibility of insoluble parts with solvent, and depend on the relative importance of each contribution. [19,20] This is a feasible route to fabrication of a micelle-like system, which is used to fix the porphyrin assemblies with high color purity of red fluorescence not only in solution but also in the solid state.…”