Adsorption of monodisperse polybutadienes on carbon black, 2 Bulk adsorption

Abstract

Abstract The adsorption on carbon black (CB) of a series of monodisperse polybutadienes (PBs) with different molecular weights (Mn in the range of 3000 to 120 000) but identical microstructure (1,2-PB content ≈ 80%) was studied in the bulk for different polymer/CB ratios (τ, in the range of 2 to 10 g/g). In this respect we particularly studied the evolution of the amount of polymer, which cannot be extracted from the polymer/filler system upon blending, the so-called bound polymer, and attempted to investigate the conformation of the resulting adsorbed molecules as well as the conditions that control the formation of the polymer/filler network. The conformational transition turned out to depend exclusively on molecular weight, and the networking transition to occur at constant Mn1/2/τ, essentially through an entanglement process of the adsorbed chains.