The temperature-independence of adsorption of lac dye on PEI-treated cotton fibres could be attributed to the characteristic of modified surface discussed via zeta potential.
However,these results might affect the interaction time of the dye molecule and the surface of cotton fibres and also thermodynamics of the adsorption. In addition, the PEI-treated cotton fibres demonstrated the highest amount of lac dye adsorption with respect to the BSA-treated and the untreated cotton fibres