ABSTRACT: In the present work, thiomer have been synthesized via thiourea reactions in high degree of modifica-tion and degree of substitution is 2.1. Preparation of polymer follows green chemistry protocol with respect to green solvent utilization and zero waste generation. The thiol products are responsive for further derivatization and were modified to a sulphide. The above mentioned reactions were also carried out using microwave heating to achieve maximum yet uniformmodification of red toon lignin. The extent of the derivatization processes was confirmed by iodine titration and precipitation titration. The prepared material have been characterised by some physical and chemical methods such as analytical determination, FTIR, SEM and EDX analysis. The analytical results supported highest sulphur content of 47.93% in thiomer. Synthesised green thiomers have been explored as arsenic ion sorbent at 60ppm. The result showed maximum sorption efficiency 86-90% for Fe(III) in aqueous system.