An oxidative reaction of cellulose with sodium methaperiodate was performed in order to reproduce the natural ageing of textiles. The oxidised groups were transformed into free macroradicals by treatment with UV light. In presence of acrylic monomers in the vapour phase, these reactive sites become the starting point for the graft copolymerisation of methyl methacrylate and ethyl acrylate onto cellulose. Thermal analysis is a convenient, useful and reproducible method for characterising complex organic materials from plants. In this research we have examined the thermal stability of oxidised and grafted flax and cotton using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) analyses, in order to evaluate the effect of the grafting on their thermal behaviour. In presence of acrylic grafted polymer, the thermal stability of the textiles increases. (C) 2004 Elsevier B.V. All rights reserved.