Determining the Service Life of Polychloroprene Parts: A Case Study in Aging Behavior

Abstract

This paper addresses determination of the service life of an installed elastomeric part, which is an issue of great practical use every day in industry. Unfortunately, this issue is commonly misunderstood and mishandled. The perennial confusion between “shelf life” and “service life” is clarified. A comprehensive survey of published literature on polychloroprene (CR or neoprene) aging is provided. The methodology, considerations and pitfalls of similarity analysis, accelerated heat aging and prediction using activation energy are illustrated with a case study. Shear in the dynamic mode, tensile, hardness, specific gravity and volume swell were the tests used to quantify the effect of heat aging. Tensile modulus and volume swell were determined to be the tests most sensitive to changes resulting from heat aging while specific gravity was the least sensitive. Although illustrated by an example of a polychloroprene part, this methodology is equally valid for the assessment of other elastomers also.