Comparison of the Rates of Polypropylene Fibre Degradation Caused by Artificial Light and Sunlight

The rates of degradation of two types of polypropylene (PP) fibres caused by sunlight and xenon tube light were assessed. Changes in the tensile strength and elongation at break of the fibres as well as changes in the fibre surface topography due to their irradiation with the same doses of UV radiation of both types of light were compared. The tensile strength of PP fibres exposed to xenon tube light decreases four up to six times faster than that of PP fibres exposed to sunlight during the summer season. The elongation at break of these fibres decreases about four times faster. The light emitted by an xenon tube causes consider ably greater damage to the fibre surface in the form of crosswise cracks, although there are fewer of which than in the case of sunlight.