The main development in macromolecular complexation in aqueous media due to hydrogen bonding over the last decade has been a better understanding of the process of complex formation. Meanwhile an ever growing interest has occurred in introducing hydrogen bonding into the polymers which originally lack donor or acceptor groups. For such polymer solutions it has been demonstrated that the transition from separated coils to complex aggregates takes place when the content of introduced interaction sites reaches a certain level. For the blends with controllable hydrogen bonding in the solid state, the relevant experiments have shown that immiscibility-miscibility-complexation transitions occur upon progressive increase in the density of hydrogen bonding.

Interpolymer Complexation and Miscibility Enhancement by Hydrogen Bonding

Unusual pH-Dependent Polarity Changes in PAMAM Dendrimers: Evidence for pH-Responsive Conformational Changes

The contribution of anionic polymer structural features to mucoadhesion

The effect of pH on the complex formation between poly(acrylic acid) (PAA) and poly(ethylene oxide) (PEO) has been studied in aqueous solutions by turbidimetric and fluorescent methods It was shown that the formation of insoluble interpolymer complexes is observed below a certain critical pH of complexation (pHcrit1) The formation of hydrophilic interpolymer associates is possible above pHcrit1 and below a certain pHcrit2 The effects of polymer concentrations in solution and PEO molecular weight as well as inorganic salt addition on these critical pH values were studied The polymeric films based on blends of PAA and PEO were prepared by casting from aqueous solutions with different pHs These films were characterized by light transmittance measurements and differential scanning calorimetry The existence of the pH value above which the polymers form an immiscible blend was demonstrated The transitions between the interpolymer complex, miscible blend, and immiscible blend caused by pH changes are disc

PH effects in the complex formation and blending of poly(acrylic acid) with poly(ethylene oxide).

Complexing blends of polyacrylic acid-polyethylene glycol and poly(ethylene-co-acrylic acid)-polyethylene glycol as shape stabilized phase change materials

H. Morawetz

Papers

Fluorometric study of the equilibrium and kinetics of poly(acrylic acid) association with polyoxyethylene or poly(vinyl pyrrolidone)