Study of the Properties of Rubber-Resin Compounds by Time-Domain NMR: Effect of The Resin Content

Resins play crucial roles in the tire industry as tackifi ers, reinforcing agents, and curing agents. Theymodify the rheological behaviour of rubber compounds, improving processability and enhancingmechanical properties.[1] The presence of resins alters polymer chain dynamics, impacting the 14/09/2023, 08:33 Galoá Proceedings https://proceedings.science/admin/proceedings/proceedings/100337/papers/book-of-abstracts?lang=en 71/75 viscoelastic behaviour and the fi nal mechanical properties. To achieve precise product requirementsthe miscibility between polymers and resins plays a fundamental role. In this research, we focused on studying the effect of the content of a natural resin on SBR compounds.The resin content was varied from 15 to 45 phr (parts per hundred parts of rubber). To gain insights intothe molecular dynamics and structural properties of the elastomeric blends, we employed acombination of ¹H Time Domain Nuclear Magnetic Resonance techniques.[2-3] From spin-spinrelaxation times we obtained valuable information on the molecular dynamics of the polymer chains.Additionally, fi eld-cycling NMR relaxometry allowed us to measure the spin-lattice relaxation timesacross a broad range of ¹H Larmor frequencies,[4] from 10 kHz to 35 MHz. The NMR data obtainedfrom these experiments were complemented with a range of other techniques such as rheometric,calorimetric and chemical analyses. These techniques provided a comprehensive understanding of themechanical, thermal, and vulcanization properties of the elastomeric blends. References [1] P.O. Powers Rubber Chem. Technol. 36, 1542 (1963) [2] M. Pierigé, F. Nerli, F. Nardelli, L. Calucci, M. Cettolin, L. Giannini, M. Geppi, and F. Martini Appl. Sci.13, 1939 (2023) [3] F. Nardelli, L. Calucci, E. Carignani, S. Borsacchi, M. Cettolin, M. Arimondi, L. Giannini, M. Geppi and F.Martini Polymers 14, 767 (2022) [4] F. Martini, E. Carignani, F. Nardelli, E. Rossi, S. Borsacchi, M. Cettolin, A. Susanna, et al.Macromolecules 53 (22), 10028 (2020)