Pyrolytic carbon: factors controlling in-rubber performance

Abstract

Pyrolysis of waste tyres not only tackles the environmental issues associated with disposal, but also enables the recovery of valuable products such as oils and carbon fillers for elastomeric materials. This study was instigated to benchmark the in-rubber properties of pyrolytic carbon (often referred to as pyrolysis carbon black, pCB) and to understand the compositional parameters that dictate performance. Colloidal properties suggest the pCB materials to have a reinforcing potential between that of N330 and N550 carbon blacks, whereas physical property data suggest that they are more akin to the N700 series. Fundamentally, this disparity in performance appears to be the result of carbonaceous residues on the pCB surface, which both reduce surface activity and dispersability of the recyclate. Both thermogravimetric and dynamic mechanical analyses confirmed a number of pCB samples to have the same specific surface activity, regardless of the pyrolysis process or feedstock utilised.

Tensile and Fracture Mechanical Properties of Styrene-Butadiene Rubbers (SBR) Filled with Industrial and Pyrolytic Carbon Blacks, and Organoclay

“…pCB contains inorganic materials from the initial rubber recipe (CaCO3, ZnO, SiO2) based on which it has a dual character [6]. The quality of the resulting carbon black depends on the "feedstock" (rubber recipe) and production conditions (temperature, pressure, atmosphere) [1,4,6], and on the post-treatment, as well. During oxygen-free pyrolysis the product has higher carbon content which when heat-treated at a high temperature may approach the quality of the commercial CBs.…”

“…These treatments are not always practical because some benefits of the dual structure (especially the silica content) are lost. According to Norris the guaranteed quality pCB is between N300-N700 standard CBs [6].…”

“…The pyrolytic carbon black (pCB) may well be used as rubber reinforcement [5][6][7]. pCB contains inorganic materials from the initial rubber recipe (CaCO3, ZnO, SiO2) based on which it has a dual character [6]. The quality of the resulting carbon black depends on the "feedstock" (rubber recipe) and production conditions (temperature, pressure, atmosphere) [1,4,6], and on the post-treatment, as well.…”

“…The latter is a common feedstock of the pyrolysis itself [1,4]. The pyrolytic carbon black (pCB) may well be used as rubber reinforcement [5][6][7]. pCB contains inorganic materials from the initial rubber recipe (CaCO3, ZnO, SiO2) based on which it has a dual character [6].…”

Influence of pyrolytic carbon black and pyrolytic oil made from used tires on the curing and (dynamic) mechanical properties of natural rubber (NR)/styrene-butadiene rubber (SBR) blends

“…In recent years, Du and coworkers [14,15], Cataldo [16] and Norris et al [17] tested CBp in new rubber compounds. Jie et al [18], Jie et al [19] and Delchev et al [20] investigated the modification of CBp and studied the effect of modified CBp on the properties of NR and SBR vulcanizates.…”