Title of article :
Anomalous behaviour of comb-like dextran–polyacrylamide copolymers in mixed solvents
Author/Authors :
Rimma Sushko، نويسنده , , Dominique Sarazin، نويسنده , , Cyrille Rochas، نويسنده , , Natalya Kutsevol، نويسنده , , Jean-Michel Guenet، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2009
Pages :
8
From page :
1698
To page :
1705
Abstract :
Copolymers obtained by grafting polyacrylamide (PAA) onto dextran (DEX) have been synthesised by ceric-ion-reduced redox initiation method. These copolymers have been characterized by light scattering and self-exclusion chromatography. Viscometry measurements in mixed solvents, water/dimethyl formamide (DMF) have revealed an anomalous behaviour reminiscent of a polyelectrolyte behaviour, namely a strong upturn when decreasing polymer concentration, effect which is absent in pure water. The origin of this phenomenon has been studied by determining by means of SAXS the short-range molecular structure of these copolymers in the binary solvents. Comparison has been also performed with water/methyl formamide (MF) and water/formamide (FA) binary solvents where the pseudo-polyelectrolyte effect is absent. A molecular model is discussed on the basis of the results from SAXS that throws some light on the viscometry effect. This model considers the occurrence of an interdigitation process between the PAA grafts together with the formation of a PAA–DMF complex.
Keywords :
Methyl formamide , Graft copolymer , Dextran , Polyacrylamide , Binary solvents , DMF
Journal title :
European Polymer Journal(EPJ)
Serial Year :
2009
Journal title :
European Polymer Journal(EPJ)
Record number :
1228134
Link To Document :
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