Ozone detection by crack-induced opacity in rubber

initially transparent polybutadiene develops micron-sized surface cracks wh en stretched and exposed ro ozone. The consequent reduction in the transpar ency of the rubber provides a facile method for quantifying the ambient ozo ne concentration. The rate at which opacity develops is linearly dependent on the amount of ozone, and increases with increasing strain. This method o f detecting atmospheric ozone has high sensitivity (1 ppb), a broad dynamic range, and is unaffected by the presence of other chemicals. The surface m orphology of exposed material can be interpreted in terms of crack nucleati on and growth.