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Multiple cracking of a thin platinum film deposited on polyethylene terephtalate, isoprene rubber, and natural rubber substrates under tensile deformation was studied by light and scanning electron microscopy. The cover fractures on several fragments elongated in the direction perpendicular to the loading direction. The width of the fractured platinum fragments depends on the thickness of the deposited layer and applied tensile stress. A semiempirical equation describing the average width of the cover fragments was obtained. Appearance of a wavy pattern on an originally smooth surface of composites with rubberlike polymer substrate was observed. The mechanism of the appearance of the surface wave is a mechanical buckling instability of the cover under compressive force.

The fragmentation of thin platinum films, nanometers thick, deposited on isoprene rubber and poly(ethylene terephthalate) substrates was studied. Light and scanning electron microscopy was used. The length of a fragment depends on the thickness of the coating film and the tensile stress applied to the specimen. An equation describing the tensile stress in an elastic coating fragment is derived. The equation is used to analyze the fragmentation of a coating film under tension. Two stages of fragmentation are distinguished. At low strains, when the length of the fragments is lower than the ineffective length, fragmentation is occasional, as determined by defects in the coating. At high strains, the mechanism of fragmentation changes to the division of the fragments into halves. The division repeats when the load is doubled. During this stage of fragmentation, the crack density is proportional to the applied stress and reversibly proportional to the thickness of the coating.

New phosphorescent oxygen-sensitive materials based on nanostructured high density polyethylene and polypropylene films are described. The polymer substrates undergo treatment by a solvent crazing process to create a well-developed network of controlled, nanometer-size pores. Indicator dye molecules are then embedded by physical entrapment in such nanostructures which subsequently can be healed. Such sensors demonstrate improved working characteristics and allow simple, cost-efficient production and disposable use. They are well suited for large-scale applications such as nondestructive control of residual oxygen and "smart" packaging.