TY - JOUR
T1 - From Nanoscale to Macroscale Characterization of Sulfur-Modified Oxidized Carbon Nanotubes in Styrene Butadiene Rubber Compounds
AU - Posadas, Pilar
AU - Bernal-Ortega, Pilar
AU - Bernal, M. Mar
AU - Nogales, Aurora
AU - Navarro, Rodrigo
AU - Valentín, Juan L.
PY - 2024/7/23
Y1 - 2024/7/23
N2 - The homogeneous dispersion of carbon nanotubes (CNTs) in a rubber matrix is a key factor limiting their amazing potential. CNTs tend to agglomerate into bundles due to van der Waals interactions. To overcome this limitation, CNTs have been surface-modified with oxygen-bearing groups and sulfur. Using atomic force microscopy (AFM) techniques, a deep nanoscale characterization of the morphology, the degree of dispersion of the CNTs in the styrene butadiene rubber (SBR) matrix, and the thickness of the interfacial layer was carried out in this study. In this context, the results from nanoscale characterization showed that the thermal oxidation-sulfur treatment leads to a composite with better dispersion in the matrix, as well as a thicker interfacial layer, indicating a stronger filler–rubber interaction. The second part of this work focused on the macroscale results, such as the Payne effect, vulcanization curves, and mechanical properties. The Payne effect, vulcanization curves, and mechanical properties confirmed the lower reinforcing effect observed in the case of the chemical oxidation treatment because, on the one hand, this composite showed the highest agglomeration of CNTs after the acid treatment. On the other hand, the presence of acid residues provoked the absorption of basic accelerators on the surface of the CNTs.
AB - The homogeneous dispersion of carbon nanotubes (CNTs) in a rubber matrix is a key factor limiting their amazing potential. CNTs tend to agglomerate into bundles due to van der Waals interactions. To overcome this limitation, CNTs have been surface-modified with oxygen-bearing groups and sulfur. Using atomic force microscopy (AFM) techniques, a deep nanoscale characterization of the morphology, the degree of dispersion of the CNTs in the styrene butadiene rubber (SBR) matrix, and the thickness of the interfacial layer was carried out in this study. In this context, the results from nanoscale characterization showed that the thermal oxidation-sulfur treatment leads to a composite with better dispersion in the matrix, as well as a thicker interfacial layer, indicating a stronger filler–rubber interaction. The second part of this work focused on the macroscale results, such as the Payne effect, vulcanization curves, and mechanical properties. The Payne effect, vulcanization curves, and mechanical properties confirmed the lower reinforcing effect observed in the case of the chemical oxidation treatment because, on the one hand, this composite showed the highest agglomeration of CNTs after the acid treatment. On the other hand, the presence of acid residues provoked the absorption of basic accelerators on the surface of the CNTs.
UR - http://www.scopus.com/inward/record.url?scp=85199367585&partnerID=8YFLogxK
U2 - 10.1021/acsomega.4c02163
DO - 10.1021/acsomega.4c02163
M3 - Article
SN - 2470-1343
VL - 9
SP - 31669
EP - 31683
JO - ACS Omega
JF - ACS Omega
IS - 29
ER -