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Reinforcing fillers are necessary in rubber compounding to aid in enhancing the mechanical properties of the compound for various applications. Carbon black (CB) is currently the most common reinforcing filler used in tire compounding. Lignin, an amorphous polyphenolic material derived from plants and a by-product of the pulp and paper industry, is also an attractive material that can serve as a dispersant and as a reinforcing filler. This paper evaluates the interactions between styrene-butadiene rubber and reinforcing fillers with an electron-rich π- system, such as lignin and CB, in the presence of a graft copolymer (PB-g-PPFS) of PB and electron-deficient 2,3,4,5,6-pentafluorostyrene (PFS). The interactions are attributed to areneperfluoroarene interactions between the electron-deficient π-system of the polyperfluoroarene grafts and the electron-rich π-system of lignin and/or CB particles. The effects of improved fillerrubber interactions on mechanical properties and dynamic mechanical properties are analyzed. This paper will demonstrate the use of PB-g-PPFS as a coupling agent in rubber compounds to enhance the interaction between the filler, lignin and lignin-carbon black hybrid filler, and the rubber matrix to achieve a reduction in the hysteresis loss and enhanced filler dispersion.
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This content will become publicly available on March 28, 2026
Improvement of Carbon Black Dispersion in Mussel-Inspired Composites from Epoxidized Natural Rubber Using Aromatic Interactions
A mussel-inspired mechanism was used to solve the problem of filler aggregation in rubber composites. This research aims to improve carbon black (CB) dispersion in epoxidized natural rubber (ENR) composites through π−π stacking and cation−π interactions by adding dopamine (D). In this study, various aromatic interactions (π−π stacking and cation−π interactions) between the D-functionalized ENR molecules and the surface of the CB were observed by Fourier transform infrared (FTIR) and Raman spectroscopy. Notably, the small and wideangle X-ray scattering (SAXS/WAXS) analyses supported our inference from the rubber processing analysis (RPA) and transmission electron microscopy (TEM) results that the aromatic interactions enhanced the CB dispersion in ENR composites. This phenomenon improved the tensile strength (138%), Young’s modulus (93%), and energy-saving properties (50%). Finally, this research provided an alternative strategy using mussel-inspired material to solve the CB aggregation problem in rubber products, yielding ENR composites with superior performance properties.
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- Award ID(s):
- 1933487
- PAR ID:
- 10592658
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Applied Polymer Materials
- Volume:
- 7
- Issue:
- 6
- ISSN:
- 2637-6105
- Page Range / eLocation ID:
- 3576 to 3587
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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