Graft polymerization onto wool fibre for improved functionality

•Internal deposition of specific monomers into the wool can alter its physiochemical properties.•Grafting onto wool provide a wider scope to diversify wool applications.•The major wool grafting mechanisms are summarized in this review.•The effect of important parameters on the grafting reaction is discussed. Internal deposition of specific monomers into the wool structure can alter its physiochemical properties, such as, improving thermal and mechanical stability, or improving the chemical resistance. Wool has a number of functional pendant groups e.g., thiol, amino and hydroxyl with the ability to form bonds with various vinyl monomers. There are a number of irradiation and chemical-based methods for the initiation of the grafting including metal and non-metal ion oxidisers and hydroperoxides. In this review, the techniques that are available for the internal deposition of the different monomers into the wool structure were reviewed with a focus on the properties of the grafted wool, such as, the thermal stability and the chemical and mechanical properties. The major grafting mechanisms are summarized and the effect of important parameters on the grafting reaction are discussed. These include time, temperature, pH and the concentration of grafting initiators and the monomers.