Polymer complexation

Phenolics. PVP readily complexes phenolics of all types to some degree, the actual extent depending on stmctural features such as number and orientation of hydroxyls and electron density of the associated aromatic system. A model has been proposed (102). Complexation with phenoHcs can result in reduced PVP viscosity and even polymer-complex precipitation (103). 

Polymer/Polymer Complexes. PVP complexes with other polymers capable of interacting by hydrogen-bonding, ion-dipole, or dispersion forces. For example mixing of PVP with poly(acryHc acid) (PAA) in aqueous solution results in immediate precipitation of an insoluble complex (113). Addition of base results in dismption of hydrogen bonding and dissolution (114—116). Complexes with a variety of poly-acids (117) and polyphenols (118) have been reported. The interest in compatibiHty on a molecular level, an interesting phenomenon rarely found to exist between dissimilar polymers, is favored by the abiHty of PVP to form polymer/polymer complexes. 

Adding hydrogen terminates the propagating polymer. The reaction between the polymer complex and the excess triethylaluminum also terminates the polymer. Treatment with alcohol or water releases the polymer ... 

The stability of the enzyme-polymer complex and its dissociation upon the variation of pH depends on the structural and other physico-chemical properties of CP and enzyme molecule. Thus, a Biocarb-T heteroreticular biosorbent (Fig. 26) is characterized by a stability of its complex with ot-amylase (under the condition of its stabilization) in acid solutions and a complete dissociation of the complex during isolation of the active enzyme at pH 7-8. 

We also found the saturation kinetics for alkaline hydrolyses of 44 (PNPA), 3-nitro-4-acetoxybenzoic acid 56 (NABA), and 3-nitro-4-acetoxybenzenearsonie acid 57 (NABAA) in the presence of QPVP1025. If ester-polymer complex formation occurs prior to the attack of OH-, Eq. (5) holds, according to Bunton etal. 103 where K is the equilibrium association constant of polyelectrolyte (PE) and ester (S), and kt the first-order rate coefficients1035, PE, S, and P indicate the poly-... 

Theng, B.K.G. 1979. Formation and properties of clay-polymer complexes. Amsterdam. 

The ionic conductivity of the MEEP/metal salt systems was improved by adding a-Al203 particles into the complexes. Chen-Yang [603] obtained a conductivity 0=9.7x10" S cm" for the composite polymer complex MEEP/Li-CIO4/2.5 wt% AI2O3. The cation transport number was in this case 0.77. 

The ionic conductivity of complexes of the polymer VIII n=3 with potassium, sodium and cesium thiocyanates were also determined. The conductivity of the polymer complexed with CsSCN is in the order of 10" S cm" at 30 °C, and lO- Scm-i at 90 °C [616]. 

This type of DNA/polymer complex includes DNA alone, since both DNA strands are linked via hydrogen bonding. Also included are DNA assemblies containing sequence blocks that do not participate in double-helix formation. 

Theng, BKG, Eormation and Properties of Clay-Polymer Complexes, Elsevier, New York, 1979. 

The synergism of surfactant-polymer complex formation has been studied by gel permeation chromatography [114],... 

I Iliopoulos, R Audebert, C Quivoron. Reversible polymer complexes stabilized through hydrogen bonds. In P Russo, ed. Reversible Polymeric Gels and Related Systems. ACS Symp Ser 350. Washington, DC American Chemical Society, 1987, pp 72-86. 

The erosion or dissolution of the polymer complex during the application... 

IC Kwon, YH Bae, SW Kim. Heparin release from polymer complex. J Controlled Release 30 155-158, 1994. 

Sedilo, L.P., Newlove, J.C., Peiffer, D.G., and Lundberg, R.D. "Hydrocarbon Soluble Polymer Complexes Useful as Viscosifiers in Fracturing Operations," US Patent 4,615,393(1986). 

The organoboron polymer complex was prepared as follows. First, poly(organoboron halide)55 was prepared according to the reported method, by hydroboration polymerization between 1,7-octadiene and the monobromoborane dimethylsuffide complex. The polymer obtained was then reacted with half an equivalent of methanol and 1-methylimidazole to give the corresponding copolymer efficiently (scheme 4). The structure of the polymer was characterized by H- and UB-NMR spectra. 

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