Rheological properties of silica dispersions stabilized by stereoregular poly(methyl methacrylate).
The adsorption of stereoregular polymers and its effect on the conformation and dynamics of the polymer at interfaces are only poorly understood. 1H NMR has revealed a lowering of the peaks assigned to isotactic sequences whatever the PMMA tacticity, which provides evidence of stereospecific adsorption of the isotactic segments on silica. Entropic factors are therefore assumed to control the configuration of the adsorbed layer. Tacticity-dependent rheological behavior is revealed by dynamic investigations carried out on silica dispersions. The driving forces likely to induce the stereoselective adsorption and tacticity-dependent rheology of suspensions are discussed.
Laboratoire des matériaux à propriétés spécifiques, Université de Toulon et du Var, avenue de l'université BP 132, 83 957 La Garde Cedex, France. pascal.carriere@univ-tln.fr
Pascal
P
Carriere
Jean-François
JF
Feller
Dominique
D
Dupuis
Yves
Y
Grohens
D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D012212:Rheology; D012822:Silicon Dioxide / Q000737:chemistry*; D013237:Stereoisomerism
D012822:Silicon Dioxide; D019904:Polymethyl Methacrylate