Thermo‐Oxidative Aging Behavior and Lifetime Prediction of Rubber Latex Foam with Various Natural‐to‐Synthetic Ratios

Abstract

Rubber latex foam (RLF) is widely used in daily life and its characteristics are active areas of research. However, the thermo‐oxidative aging behaviors of RLF at high temperatures have not been elucidated in detail. Herein this study, the aging degree and characteristics of five types of RLF materials with various ratios of natural rubber latex and synthetic rubber latex are investigated by using the yellowness index (YI), whiteness index, cross‐linking density, indentation density, and infrared spectrum. It is indicated in the results that the structural failure degree, YI, and cross‐linking density of the sample increased linearly with increasing natural‐to‐synthetic ratio (N/R ratio). It is observed that all RLF samples with various N/R ratios undergo aging reactions during the aging process, but the aging degree and aging rate of the samples differ. Furthermore, a lifetime prediction model is calculated by the standard method and the variable activation energy method, and the YI of RLF is used as an index to evaluate the service life, which serves as a useful tool for the quality evaluation of RLF.