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Hydrogen peroxide can be catalyzed to bleach cotton fibers at temperatures as low as 308C by incorporating dinuclear tri-l-oxo bridged manganese(IV) complex of the ligand 1,4,7-trimethyl-1,4,7-triazacyclononane (MnTACN) as the catalyst in the bleaching solution. The catalytic system was found to be more selective under the conditions applied than the non-catalytic H 2 O 2 system, showing better bleaching performance while causing slightly lower decrease in degree of polymerization (DP) of cellulose. In order to gain fundamental knowledge of the bleach effect on cotton fibers and cellulose as its main component, especially after catalytic bleaching, X-ray Photoelectron Spectroscopy (XPS) was used to study surface chemical effects. The Washburn method was applied to investigate wetting properties, and liquid porosity was used to obtain pore volume distribution (PVD) plots. Parallel analyzes performed on model cotton fabric, i.e. ''clean'' cotton fabric stained with morin -a pigment regularly found in native cotton fiber, helped to differentiate between pigment oxidation and other bleaching effects produced on the (regular) industrially scoured cotton fabric. Bleaching was not limited to the chemical action but also affected cotton fiber capillary parameters most likely due to the removal of non-cellulosic materials as well as chain-shortened cellulose.

This study examines in detail the influence of low-temperature plasma and biopolymer chitosan treatments on wool dyeability. Wool knitted fabrics were treated and characterized by whiteness and shrink-resistance measurements. Surface modification was assessed by contactangle measurements of human hair fibers, which were used as a model to study the wetting properties of the treated wool knitted fabrics. The dyeing behavior was assessed from the diffusion mechanism point of view. The dyeing kinetics were measured at two different pHs (4.2 and 6.5) and three different temperatures (60, 85, and 100°C) to gain information about the contribution of the surface modification treatment to the dyeing mechanism. The exhaustion and reflectance data were compared, and the apparent diffusion coefficients were calculated. On the basis of the obtained results, a model for the dyeing mechanism of the chitosan treated wool was proposed. When treated with chitosan, the polymer sheath spread on the surface of the fibers acted as a predominant dyeing site in very short dyeing times, thus interacting with the dye and in later stages imparting the dye to the wool fiber.

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We have dcveloped a homogeneous model system to study the mechanism of hydrogen peroxide bleaching using [Mn2O3(N,N'N ''-trimethyl-1-1,4,7-triazacyclononane)(2)](PF6)(2) (MnTMTACN) as catalyst. Thee primary model pigment exarnined is morin (3,5,7,2',4'-pentahydroxyflavone) owing to its presence in native cotton 1-iber. Additionally, a series of model compounds with systematic structural diffierences are examined in order to facilitate the development ofa mechanistic understanding of the bleaching system. The pigment oxidative degradation reaction is monitored by UV-Vis spectrophotornetry. The influence of pH is examined in both hornooeneous and heterogenous model systems. The use of MnTMTACN catalyst enables low-temperature hydrogen peroxide bleaching of cotton fabric at slightly lower pH values

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The new concept of the combined treatment consisting of specific fibre surface tailoring and activation prior to biopolymer or enzyme post-application is introduced. Low-temperature plasma treatment is considered as very useful for superficial treatment of wool and hemp. Some interesting combinations of low-temperature plasma and enzymatic treatments are presented in this paper. These treatments result in an increase in wettability, dimensional stability, polymer adhesion and dyeability of both, wool and hemp fabrics.

The modern textile fibre treatments aim to obtain the required level of beneficial effect while attempting to confine the modification to the fibre surface. Recently, much attention has been focused on different physical methods of fibre surface modification, cold plasma treatment being considered as very useful. Moreover, there are efficient chemical methods available, such as peroxide, biopolymer and enzyme treatment. Some interesting combinations of these physical and chemical surface modification methods as means to modify fibre surface topography and thus controlling the surface-related properties of the fibre are presented in this paper. The properties obtained are discussed on the basis of the physico-chemical changes in the surface layer of the fibre, being assessed by wettability and contact angle measurements, as well as by FTIR-ATR and XPS analysis. The SEM and AFM technique are used to assess the changes in the fibre surface topography and to correlate these changes to the effectiveness, uniformity and severity of the textile fibre surface modification treatments