Modeling the Degradation of Natural Rubber Male Condoms

Most condom manufacturers claim a 5 year shelf-life for their products; however, condoms can decay much more rapidly than the reported shelf-life would suggest, because of the uncontrolled storage conditions. For this reason, development of mathematical model to predict condom shelf-life as a function of storage conditions can be very useful. In this work, six brands of condoms were aged under subtropical ambient conditions for 5 years and under accelerated conditions at four temperatures for various times. The changes in burst pressure and burst volume were used as the main indicators of product degradation. Experimental data were analyzed and two mathematical models (both based on the reparameterized Arrhenius equation) were proposed to describe the obtained data. It is shown for the first time that it is possible to estimate and predict the degradation of natural rubber condoms with confidence with the help of the proposed models, based on data obtained from accelerated degradation experiments, provided that different activation energies are used for the burst pressure and volume. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 120: 839-849, 2011