A waterborne bio-based polymer pigment: colored regenerated cellulose suspension from waste cotton fabrics

Waterborne bio-based polymer pigments are promising environmentally friendly coloring materials. In this work, novel colored cellulose suspensions applicable for coloring, labelling and anti-counterfeiting were prepared from waste cotton fabrics. It was demonstrated that cellulose regenerated from a phosphoric acid solution of waste cotton fabrics could be conveniently colored by reacting with reactive dyes. The high specific surface area of the regenerated cellulose(RC) allowed for high color build-up of up to 210mg/g dye fixation and K/S value of up to 31. The resulting colored regenerated cellulose(CRC) suspension had typical characteristics of regenerated cellulose and was used to color polyurethane (PU). The resulting colored PU films exhibited excellent color fastness/resistance to leaching when soaked in water. This study demonstrated a way of alleviating the environmental burden of waste cotton fabrics by converting them to high value-added colored waterborne cellulose suspension. Graphical abstractPreparation and application of CRC suspensions from waste cotton fabrics [GRAPHICS] .