Solvent effect on the complex formation of poly(methacrylic acid) with proton‐accepting polymers

A pair of polymers may interact with each other through hydrogen bond and form a polymer complex. Such polymer complex formation is affected by several chemical and physical factors, especially by solvent properties. This solvent effect was studied in the complex formation of poly(methacrylic acid) with a series of proton‐accepting polymers in aprotic solvents. The extraordinary behaviour of polymer complexes in dimethyl sulfoxide was well explained in terms of the strong interaction between proton‐donating polymer and dimethyl sulfoxide. In addition, a stronger proton‐accepting polymer, viz. poly(N,N‐dimethyl‐N′,N′,N″,N″‐tetramethylenephosphoramide), was synthesized. This polymer could form a polymer complex with poly(methacrylic acid) through hydrogen bond even in dimethyl sulfoxide. Selective polymer complex formation was achieved by controlling such solvent properties.