Large step shear experiments revealed through particle tracking velocimetry that entangled polymeric liquids display either internal macroscopic movements upon shear cessation or rupturelike behavior during shear. Visible inhomogeneous motions were detected in five samples with the number of entanglements per chain ranging from 20 to 130 at amplitudes of step strain as low as 135%.

Velocity profiles of six entangled polybutadiene solutions (PBD) have been determined during startup shear using a particle tracking velocimetric (PTV) technique, where the number Z of entanglements per chain in these solutions varies from 13 to 119, depending on the PBD molecular weight and solution concentration. Flow behavior of these solutions at various rates in the stress plateau region has been investigated in both paralleldisk and cone-plate cells. For the least entangled solution with Z ) 13, homogeneous shear was observed under all flow conditions. The solution with Z ) 27 displayed inhomogeneous shear after the stress maximum before returning to a linear velocity profile at long times. For solutions with Z g 40, shear banding was observed in both transient and steady states for a range of shear rates in the stress plateau region. At sufficiently high rates, shear homogeneity returns in steady state for these solutions (Z g 40) after initial banding.

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A new general anionic functionalization methodology is described based on (a) the quantitative silyl hydride functionalization of well‐defined polymeric organolithium compounds with either dimethylchlorosilane (ω‐chain end functionalization) or dichloromethylsilane (in‐chain functionalization) and (b) reaction of the silyl hydride‐functionalized polymer with a functionalized alkene using Karstedt's Pt(0) hydrosilylation catalyst.