Effect of carbon nanotubes content on the vulcanization kinetic in styrene–butadiene rubber compounds

Because of the chemically crosslinked 3D molecular structure of rubbers, their recycling is a challenging task, especially when cost efficiency is also considered. One of the most straightforward procedures is the grinding of discarded rubber products with subsequent devulcanization. The devulcanized rubber can be used as a feedstock for fresh rubber compounds or can be blended with uncured virgin rubber and thermoplastic polymers to form thermoplastic dynamic vulcanizates (TDVs). TDVs combine the beneficial (re)processability of thermoplastics and the elastic properties of rubbers. Our current work focuses on the development of polypropylene (PP)-based TDVs with the use of a tire model rubber (MR) composed of natural rubber (NR) and styrene-butadiene rubber (SBR) in a ratio of 70/30. The research target was the partial substitution of the above fresh MR by microwave devulcanized crumb rubber (dCR). TDVs were produced by continuous extrusion, and the effects of composition (PP/MR/dCR = 40/60/0…50/35/15) and processing parameters (different screw configurations, temperature profiles, the feeding method of PP) were investigated. Results showed that the fresh rubber compound can be replaced up to 10 wt % without compromising the mechanical properties of the resulting TDV.

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Filler-polymer interactions in both silica and carbon black-filled styrene-butadiene rubber compounds

Journal of Polymer Science Part B Polymer Physics ◽

10.1002/1099-0488(20010215)39:4<439::aid-polb1016>3.0.co;2-3 ◽

2001 ◽

Vol 39 (4) ◽

pp. 439-445 ◽

Cited By ~ 29

Author(s):

Sung-Seen Choi

Keyword(s):

Carbon Black ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Rubber Compounds ◽

Polymer Interactions ◽

Styrene Butadiene

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Organic Zinc Salts as Pro-Ecological Activators for Sulfur Vulcanization of Styrene–Butadiene Rubber

Polymers ◽

10.3390/polym11101723 ◽

2019 ◽

Vol 11 (10) ◽

pp. 1723 ◽

Cited By ~ 4

Author(s):

Magdalena Maciejewska ◽

Anna Sowińska ◽

Judyta Kucharska

Keyword(s):

Zinc Oxide ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Zinc Ions ◽

Organic Zinc ◽

Rubber Compounds ◽

Curing Characteristics ◽

Sulfur Vulcanization ◽

Zinc Salts ◽

Styrene Butadiene

Organic zinc salts and complexes were applied as activators for sulfur vulcanization of styrene–butadiene elastomer (SBR) in order to reduce the content of zinc ions in rubber compounds as compared with conventionally used zinc oxide. In this article, the effects of different organic zinc activators on the curing characteristics, crosslink densities, and mechanical properties of SBR as well as the aging resistance and thermal behavior of vulcanizates are discussed. Organic zinc salts seem to be good substitutes for zinc oxide as activators for sulfur vulcanization of SBR rubber, without detrimental effects to the vulcanization time and temperature. Moreover, vulcanizates containing organic zinc salts exhibit higher tensile strength and better damping properties than vulcanizate crosslinked with zinc oxide. The application of organic zinc activators allows the amount of zinc ions in SBR compounds to be reduced by 70–90 wt % compared to vulcanizate with zinc oxide. This is very important for ecological reasons, since zinc oxide is classified as being toxic to aquatic species.

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