Temperature‐induced aggregation of the copolymers of N‐isopropylacrylamide and sodium 2‐acrylamido‐2‐methyl‐1‐propanesulphonate in aqueous solutions

A series of random copolymers of N-isopropylacrylamide (NIPAM) and sodium 2-acrylamido-2-methyl-1-propanesulphonate (AMPS) was synthesized by free-radical copolymerization. The content of AMPS in the copolymers ranged from 1.1 to 9.6 mol %. The lower critical-solution temperature (LCST) of copolymers in water increased strongly with an increasing content of AMPS. The influence of polymer concentration on the LCST of the copolymers was studied. For the copolymers with a higher AMPS content, the LCST decreased faster with an increasing concentration than for copolymers with a low content of AMPS. For a copolymer containing 1.1 mol % of AMPS the LCST dropped by about 3 °C when the concentration increased from 1 to 10 g/L, whereas for a copolymer containing 9.6 mol % of AMPS the LCST dropped by about 10 °C in the concentration range from 2 to 10 g/L. It was observed that the ionic strength of the aqueous polymer solution very strongly influences the LCST. This effect was most visible for the copolymer with the highest content of AMPS (9.6 mol %) for which an increase in the ionic strength from 0.2 to 2.0 resulted in a decrease in the LCST by about 27 °C (from 55 to 28 °C), whereas for the copolymer containing 1.1 mol % of AMPS the LCST decreased only by about 6 °C (from 37 to 31 °C) when the ionic strength increased from 0.005 to 0.3. The reactivity ratios for the AMPS and NIPAM monomer pairs were determined using different methods. The values of rAMPS and rNIPAM obtained were 11.0–11.6 and 2.1–2.4, respectively. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2784–2792, 2001

[1]  M. Kępczyński,et al.  New polymeric photosensitizers , 2001 .

[2]  P. C. Rieke,et al.  Temperature-Sensitive Surfaces Prepared by UV Photografting Reaction of Photosensitizer and N-Isopropylacrylamide , 2000 .

[3]  D. H. Napper,et al.  Effect of Heating Rate on Nanoparticle Formation of Poly(N-isopropylacrylamide)−Poly(ethylene glycol) Block Copolymer Microgels , 2000 .

[4]  W. Xue,et al.  Observations on some copolymerisations involving N-isopropylacrylamide , 2000 .

[5]  K. Ulbrich,et al.  Thermally Controlled Association in Aqueous Solutions of Diblock Copolymers of Poly[N-(2-hydroxypropyl)methacrylamide] and Poly(N-isopropylacrylamide) , 2000 .

[6]  J. Feijen,et al.  Quasi-Living Polymerization of N-Isopropylacrylamide onto Poly(ethylene glycol) , 2000 .

[7]  K. Akiyoshi,et al.  Controlled association of amphiphilic polymers in water : Thermosensitive nanoparticles formed by self-assembly of hydrophobically modified pullulans and poly(N-isopropylacrylamides) , 2000 .

[8]  F. Winnik,et al.  Solution Properties of Hydrophobically Modified Copolymers of N-Isopropylacrylamide and N-Glycine Acrylamide: A Study by Microcalorimetry and Fluorescence Spectroscopy , 2000 .

[9]  K. Nishinari,et al.  Effect of the Introduced Charge on the Thermal Behavior of N-Isopropylacrylamide Gels in Water and NaCl Solutions , 2000 .

[10]  S. Varghese,et al.  Designing new thermoreversible gels by molecular tailoring of hydrophilic-hydrophobic interactions , 2000 .

[11]  Jing Zhang,et al.  Synthesis and Characterization of pH- and Temperature-Sensitive Poly(methacrylic acid)/Poly(N-isopropylacrylamide) Interpenetrating Polymeric Networks , 2000 .

[12]  A. Hoffman,et al.  Thermoprecipitation of streptavidin via oligonucleotide-mediated self-assembly with poly(N-isopropylacrylamide). , 1999, Bioconjugate chemistry.

[13]  C. Pichot,et al.  STUDY OF CATIONIC N-ISOPROPYLACRYLAMIDE-STYRENE COPOLYMER LATEX PARTICLES USING FLUORESCENT PROBES , 1999 .

[14]  Chi Wu,et al.  Self-association of poly(N-isopropylacrylamide) and its complexation with gelatin in aqueous solution , 1999 .

[15]  F Liu,et al.  Modulating insulin-release profile from pH/thermosensitive polymeric beads through polymer molecular weight. , 1999, Journal of controlled release : official journal of the Controlled Release Society.

[16]  K. Kono,et al.  Temperature sensitization of liposomes using copolymers of N-isopropylacrylamide. , 1999, Bioconjugate chemistry.

[17]  Françoise M. Winnik,et al.  Contribution of Hydrogen Bonding to the Association of Liposomes and an Anionic Hydrophobically Modified Poly(N-isopropylacrylamide)† , 1999 .

[18]  Y. Bae,et al.  Insulin release from islets of Langerhans entrapped in a poly(N-isopropylacrylamide-co-acrylic acid) polymer gel. , 1999, Journal of biomaterials science. Polymer edition.

[19]  T. Okano,et al.  Growth factor release from thermally reversible tissue culture substrates. , 1998, Journal of controlled release : official journal of the Controlled Release Society.

[20]  P. C. Rieke,et al.  Reversible Surface Properties of Glass Plate and Capillary Tube Grafted by Photopolymerization of N-Isopropylacrylamide , 1998 .

[21]  D. Bergbreiter,et al.  Poly(N-isopropylacrylamide) Soluble Polymer Supports in Catalysis and Synthesis , 1998 .

[22]  M. Shibayama,et al.  Kinetics of Volume Phase Transition in Poly(N-isopropylacrylamide-co-acrylic acid) Gels , 1998 .

[23]  M. Akashi,et al.  Effects of salt on the temperature and pressure responsive properties of poly(N-vinylisobutyramide) aqueous solutions , 1998 .

[24]  Jan Feijen,et al.  Thermosensitive Micelle-Forming Block Copolymers of Poly(ethylene glycol) and Poly(N-isopropylacrylamide) , 1997 .

[25]  B. Cabane,et al.  Effects of surfactants on thermally collapsed Poly(N-isopropylacrylamide) macromolecules , 1997 .

[26]  W. Bare,et al.  Reactions of Laser-Ablated Vanadium Atoms with Dioxygen. Infrared Spectra of VO, VO 2 , OOVO 2 , and V 2 O 2 in Solid Argon , 1997 .

[27]  F. Winnik,et al.  Mechanism of the interaction of hydrophobically-modified poly-(N-isopropylacrylamides) with liposomes. , 1997, Biochimica et biophysica acta.

[28]  E. Kokufuta,et al.  On the Local Binding of Ionic Surfactants to Poly(N-isopropylacrylamide) Gels , 1997 .

[29]  李梅,et al.  Fluorescence Studies of Hydrophobic Association of Fluorocarbon-Modified Poly(N-isopropylacrylamide) , 1997 .

[30]  J. Rička,et al.  Coil−Globule Transition of Poly(N-isopropylacrylamide): A Study of Polymer−Surfactant Association , 1996 .

[31]  F. Winnik,et al.  Pyrene-labeled amphiphilic poly-(N-isopropylacrylamides) prepared by using a lipophilic radical initiator: synthesis, solution properties in water, and interactions with liposomes , 1995 .

[32]  Vladimir N. Uversky,et al.  "Domain" Coil-Globule Transition in Homopolymers , 1995 .

[33]  H. Ringsdorf,et al.  Hydrophobically-modified poly(N-isopropylacrylamides) in water : a look by fluorescence techniques at the heat-induced phase transition , 1992 .

[34]  H. Ringsdorf,et al.  Hydrophobically-modified poly(N-isopropylacrylamides) in water: probing of the microdomain composition by nonradiative energy transfer , 1992 .

[35]  Jaroslav Ricka,et al.  Coil-globule transition of poly(N-isopropylacrylamide): a study of segment mobility by fluorescence depolarization , 1991 .

[36]  H. Ringsdorf,et al.  Interactions of surfactants with hydrophobically-modified poly(N-isopropylacrylamides). 1. Fluorescence probe studies , 1991 .

[37]  H. Ringsdorf,et al.  Fluorescence studies of hydrophobically modified poly(N-isopropylacrylamides) , 1991 .

[38]  H. Ringsdorf,et al.  Bis(1-pyrenylmethyl) ether as an excimer-forming probe of hydrophobically modified poly(N-isopropylacrylamides) in water , 1991 .

[39]  H. Ringsdorf,et al.  Interaction of Hydrophobically‐Modified Poly‐N‐isopropylacrylamides with Model Membranes—or Playing a Molecular Accordion , 1991 .

[40]  F. Winnik.  Phase transition of aqueous poly-(N-isopropylacrylamide) solutions: a study by non-radiative energy transfer , 1990 .

[41]  F. Winnik.  Quenching of fluorescence from pyrene-labeled poly(N-isopropylacrylamide) solutions heated above their lower critical solution temperature , 1990 .

[42]  Toyoichi Tanaka,et al.  Phase transition in polymer gels induced by visible light , 1990, Nature.

[43]  K. Kubota,et al.  Single-chain transition of poly(N-isopropylacrylamide) in water , 1990 .

[44]  Allan S. Hoffman,et al.  Applications of thermally reversible polymers and hydrogels in therapeutics and diagnostics , 1987 .

[45]  H. Harwood.  Structures and compositions of copolymers , 1987 .

[46]  Toyoichi Tanaka,et al.  Volume phase transition in a nonionic gel , 1984 .

[47]  T. Kelen.  Analysis of the Linear Methods for Determining Copolymerization Reactivity Ratios. I. A New Improved Linear Graphic Method , 1975 .

[48]  M. Heskins,et al.  Solution Properties of Poly(N-isopropylacrylamide) , 1968 .

[49]  S. Ross,et al.  Linear method for determining monomer reactivity ratios in copolymerization , 1950 .