Molecular Insights into End-Group Cluster Formation in Natural Rubber Induced by <scp>l</scp> -Quebrachitol, a Major Component of Natural Rubber Serum Waste

+ Q). Using equilibrated molecular dynamics simulations, we examine static, dynamic, and structural properties, including the end-to-end distance, radius of gyration, end-to-end vector autocorrelation, stress autocorrelation, diffusion coefficients, radial distribution functions of terminal groups around Q, and survival probabilities of terminal groups around Q. The incorporation of Q markedly slows rotational and stress relaxation in both ester- and hydroxy-terminated PI melts through the formation of stable Q-α5 and Q-α6 clusters mediated by a strong bifurcated hydrogen bonding. These results demonstrate that Q-induced physical junctions play a central role in enhancing the mechanical performance of NR.