Estimating shelf life and degradation mechanisms of nitrile butadiene rubber for viscoelastic dampers

• Published in: Journal of elastomers and plastics Vol. 56; no. 4; pp. 434 - 453
• Main Authors: Ammineni, Syam Prasad, Lingaraju, Dumpala, Nagaraju, Cherukuri
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01-06-2024
• Subjects: activation energy; kinetic modelling; viscoelastic damper; shelf-life estimation; Nitrile butadiene rubber
• ISSN: 0095-2443; 1530-8006
• DOI: 10.1177/00952443241243378

This study investigates the shelf life of nitrile butadiene rubber (NBR) based on age and temperature factors. Natural aging of nitrile butadiene rubber samples is performed under laboratory conditions for 2 years, followed by thermogravimetric analysis to evaluate Arrhenius parameters. Toop’s equation is used to predict shelf life at 5% conversion rate. Model-free kinetic methods, including Ozawa-Flynn-Wall (OFW), Kissinger-Akahira-Sunose (KAS), and Kissinger, estimate shelf life at different temperatures for both virgin and naturally aged nitrile butadiene rubber. Results show close correlation between KAS and Kissinger methods, with slight variations in activation energy impacting shelf life. Fourier-transform infrared spectroscopy (FTIR) tests assess functional group changes with age. Virgin nitrile butadiene rubber activation energy: OFW-73.33 kJ/mol, KAS-68.43 kJ/mol. Aged nitrile butadiene rubber activation energy: OFW-72.57 kJ/mol, KAS-67.88 kJ/mol. Shelf life at 40°C: Virgin nitrile butadiene rubber - OFW-111.29 years, KAS-26.31 years. Aged nitrile butadiene rubber - OFW-89.01 years, KAS-22.37 years. These findings provide valuable insights for predicting and assessing nitrile butadiene rubber viscoelastic damper performance in engineering applications.