Resistance of fabric made of wool and wool/polyester mixture to environmental impact
It is important to evaluate the impact of environmental factors on textile fabrics made of fibres mixtures. The influence of natural environmental conditions, i.e. natural sun light, wind, rain and chemical materials soluble in it on the properties of natural wool fiber and a mixture of natural and synthetic fibres (wool 45% and polyester 55%) was investigated. The samples were aged under natural environmental conditions for 336 and 672 hours. Also, a comparable analysis of natural fibres and mixture of synthetic and natural fibres was done under artificial irradiation conditions, using a UV lamp. The fabrics were isolated by ultraviolet irradiation for 20, 40 and 60 hours, respectively. The water sorption, solubility in alkali solution and pH values of all fabric samples was investigated. Under the effect of natural or artificial environmental conditions, the pH value of the fabric samples decreased comparing with the initial levels. The moisture content in the fabric kept under natural conditions decreased. The weight loss value, determined by the method of solubility in alkali solution of the fibres, was higher when the fabrics samples were influenced by natural or UV irradiation conditions compared with the initial values. In all cases, the weight loss of wool fibre was higher than that of a mixture of natural and synthetic fibres, and this implies that fabrics produced from wool – a natural polymer – degrades faster under the effect of environmental factors.