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This paper describes a new method for the grafting of methacrylic acid (MAA) and other acrylic monomers onto wool fabric in aqueous medium. The novelty principally concerns the chemical approach of the redox grafting reaction that was carried out in the presence of sodium perborate (SPB) initiator. Before the grafting reaction was started, the wool fabric was treated first with a freshly prepared ferrous ammonium sulfate (FAS) solution. The so-treated fabric formed, with SPB, an efficacious redox system capable of initiating grafting of methacrylic acid (MAA) and other acrylic monomers onto the wool fabric. The effect of the polymerization conditions on the polymer criteria, namely, graft yield (%GY), homopolymer (%HP), total conversion (%TC), and grafting efficiency (%GE), was studied. These polymer criteria were found to depend spaciously upon concentrations of the Fe 2+ ion (activator), SPB (initiator), and MAA, pH of the polymerization medium, duration and temperature of polymerization. The graft copolymerization reaction has also been carried out in the presence of polymerization activators (e.g. reductant transition metal ions) and an inhibitor (e.g. hydroquinone). A suitable mechanism for the grafting processes has been suggested, in accordance with the experimental results. [ABSTRACT FROM AUTHOR]

Wood has been used as an engineering material because it is low in cost, renewable and strong and it requires low processing energy. Wood has many excellent properties that result from its exceptional combination of microstructural, ultrastructural and molecular features. The main drawback is its dimensional instability in the presence of moisture, which can affects also the biological stability. Wood is susceptible to degradation in a number of ways, including rot or decay, insect attack, fire and weathering. Each of these forms of degradation can potentially be inhibited by chemical means. New ecomaterials with biocide activity were synthesized by emulsion copolymerization of acrylic comonomers (ethyl acrylate, butyl acrylate, acrylonitrile, acrylic acid) with lignin derivatives ammonium, aluminium and chromium lignosulfonates, as partial substitutes for acrylic monomers. Having in view the biocide activity both, for acrylic comonomers and lignin derivatives, the obtained copolymers were biologically tested as new wood preservation agents. [ABSTRACT FROM AUTHOR]

Research regarding chemically modifying the wood in order to prevent its deterioration is an alternative to the protection of wood with toxic chemicals. The paper presents the research concerning the chemical modification of pine wood sawdust by esterification with acrylic monomers, in order to improve its biological resistance. [ABSTRACT FROM AUTHOR]