Ulteriori informazioni
Throughout most of this century, progress in Polymer Science took place by way of studies of dilute polymer solutions and of the solid state. More recently, attention has been focused on the semi-dilute regime. The elucidation of transi ent network and temporal gel states under conditions of moderate concentra tion by numerous hydrodynamic and optical techniques is now well established and a solid theoretical underpinning for these phenomena is in place. However, in most of the systems studied, interpolymer interactions are relatively weak forces, because in solutions oftypical polymers, strong interpolymer interactions lead to bulk phase separation. However, polymers that form highly associating structures in equilibrium solution now constitute an important class of synthetic macromolecules, and it is evident that strong intermacromolecular interactions - without accompanying phase separation - are prevalent in biopolymer sys tems as well. This behavior is generally characteristic of amphiphilic polymers, which contain both hydrophilic and hydrophobic repeat units. It is also charac teristic of systems in which two macromolecular species are complementary, such as hydrogen-bond-donating and hydrogen-bond-accepting polymers, or polycations and polyanions. Interest in associating polymer systems currently derives from both applied and fundamental questions. Synthetic water-soluble polymers bearing hydro phobic groups exhibit special rheological properties that make them well-suited as thickeners and viscosity-modifiers. Drag-reduction effects may arise in such polymer solutions, and may also be observed in polymer complexes based on hydrogen-bonding.
Sommario
I. Hydrophobically Associating Polymers.- 1 Synthesis and Characterization of Hydrophobically Associating Water-Soluble Polymers.- 2 Analysis of Hydrophobically Associating Copolymers Utilizing Spectroscopic Probes and Labels.- 3 Solution Properties of Hydrophobically Associating Water-Soluble Polymers.- 4 Aggregation of Hydrophobically Modified Polyelectrolytes in Dilute Solution: Tonic Strength Effects.- 5 Microdomain Composition in Two-Phase Hydrogels.- 6 Molecular Association and Polymerization of 1-Alkyl-4-vinylpyridinium Ions.- 7 Fluorocarbon-Modified Water Soluble Polymers.- II. Polyelectrolyte Complexes.- 8 Static Light Scattering of Polyelectrolyte Complex Solutions.- 9 Interaction Between Oppositely Charged Low Ionic Density Polyelectrolytes: Complex Formation or Simple Mixture?.- 10 Basic Properties of Soluble Interpolyelectrolyte Complexes Applied to Bioengineering and Cell Transformations.- 11 Conformation Presumption for Polysaccharide-Polylysine Complexation.- 12 Interpolymer Complexes and their Ion-Conduction.- 13 Fluorescence Probe Studies of Poly(acrylic acid) Interchain Complexation Induced by High Shear Flow and Influence of Cationic Surfactants on the Complexation.- III. Biopolymer Systems.- 14 Water-Soluble Biospecific Polymers for New Affinity Purification Techniques.- 15 Protein-Polyelectrolyte Complexes.- 16 Precipitation of Proteins with Polyelectrolytes: Role of Polymer Molecular Weight.- 17 Complex Coacervation: Micro-Capsule Formation.- 18 Complexation of Proteins with Polyelectrolytes in a Salt-Free System and Biochemical Characteristics of the Resulting Complexes.- IV. Ionomers in Solution.- 19 Ionomer Solutions: Polyelectrolyte or Ionomer behavior.- 20 Scattering Studies of Ionomer Aggregates in Nonpolar Solvents.
