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

作　　者：Paulo Sergio Rangel Cruz da Silva Gisele Cristina Valle Iulianelli Maria Inês Bruno Tavares 

机构地区：[1]Instituto de Macromoléculas Professora Eloisa Mano-IMA,Universidade Federal do Rio de Janeiro-UFRJ, Rio de Janeiro-RJ, Brasil

出　　处：《Materials Sciences and Applications》2017年第5期342-350,共9页材料科学与应用期刊（英文）

摘　　要：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, T2>H, although being a revealing as T1>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 T2>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 T2>H data indicated that the clay ratio can influence the chain degradation processes, acting to inhibit or accelerate the aging process [1] [2].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, T2>H, although being a revealing as T1>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 T2>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 T2>H data indicated that the clay ratio can influence the chain degradation processes, acting to inhibit or accelerate the aging process [1] [2].

关 键 词：DEGRADATION High Impact POLYSTYRENE Nanocomposites RELAXOMETRY Spin-Spin 

分 类 号：R73[医药卫生—肿瘤]