Spin-Spin Relaxation Time to Evaluate Degradation of HIPS/Organoclaynano Composites by Aging

Abstract

NMR relaxometry is one of the techniques that allow observing changes in the molecular mobility that come from materials’ morphology. T₁H has been used to monitor food and polymer sciences. However, T <sub> 2</sub > H, although being a revealing as T <sub> 1</sub > H, is rarely used to analyze changes in thermoplastic systems it is more sensitive to the mobile region. High Impact Polystyrene nanomaterials were prepared through solution casting and were exposed for different times to UV light in the air. The samples, removed after each exposure interval, were characterized by T <sub> 2</sub > H, focusing on the changes in the relaxation data. The results for this parameter showed that the changes in the relaxation data come from the competition of chain scission and chain recombination processes, which occurs due to the UV light influence with increased time. The T <sub> 2</sub > H data indicated that the clay ratio can influence the chain degradation processes, acting to inhibit or accelerate the aging process [1] [2].