The Effects of Surface Chemical Interactions on the Properties of Filler-Reinforced Rubbers

Abstract

1. Heat treatment of carbon black-rubber mixtures is a method of “in process” polymer grafting which gives a definite improvement in the dynamic properties of vulcanizates. 2. The heat treatment process can be more effective if chemical promoters are used. These chemical promoters function as coupling agents between filler surface and rubber. 3. With very unreactive butyl rubber an effective interaction is produced both by the addition of chemical promoters and by the use of specially active surface-modified carbon black. 4. In normal unsaturated rubbers, surface modifications of carbon black with a wide variety of groups has shown only minimal effects on rubber-reinforcing ability. Halogenated blacks have a pronounced effect on vulcanization kinetics, giving cured vulcanizates of high crosslink density. 5. Carbon black surfaces can be deactivated by calcining at high temperatures. The loss of surface-bound hydrogen may not account for this loss in surface activity. 6. Grafting of polymers to the surface of carbon black is a new method for surface deactivation. 7. Activation of carbon black surfaces by polymer grafting or other types of surface modification has not as yet been demonstrated for normal hydrocarbon rubbers.

Using a sulfur-bearing silane to improve rubber formulations for potential use in industrial rubber articles

“…These properties were similar to those reported previously for sulfur-cured carbon black-filled SBR, IR, and NBR rubbers [22,24]. It appeared that reducing the chemical curatives had no adverse effect on the rubber properties.…”

Mechanical and Electrical Properties of Elastomer Nanocomposites Based on Different Carbon Nanomaterials

“…Equation (1) was established for unfilled elastomers but it has been widely used in filled elastomeric materials (see Reference [1] and all the papers of Mark et al on filled elastomers and [51]). Dannenberg [52] explains that Equation (1) should apply to a filled vulcanizate if it can be assumed that the major function of the dispersed phase is to increase the effective strain of the rubber phase.…”

Multiwall carbon nanotube-filled natural rubber: Electrical and mechanical properties

“…Such increases in stiffness are not observed for similar loading fractions of spherical carbon black or silica particles in the same matrix, thus highlighting the effect of the high aspect ratio (length/diameter) of the nanotubes. In conventional composites, the increase in the modulus has been ascribed to a hydrodynamic effect arising from the inclusion of rigid particles in the soft matrix and to an increase in the cross-linking density created by polymerfiller interactions [1,2,26,[37][38][39][40]. But the anisometry of the filler structures as well as the quality of their dispersion can greatly affect the composite performance.…”