Abstract: A kind of ternary copolymer anionic surfactant NaOL-AA-SMAS was synthesized by aqueous solution free radical polymerization with sodium oleate (NaOL),acrylic acid (AA) and sodium methallyl sulfonate (SMAS) as starting materials.The product was applied as an ingredient of waste paper deinking agent.Optimization of conditions for the preparation of the product was conducted taking the deinking effect as criteria.Further,the product was blended with a nonionic surfactant polyethoxy lauryl ether (AEO₉) and the deinking efficacy of the blend was examined.Structure of the product was characterized by FT-IR;the molecular weight and its distribution of the product were measured by GPC;and the deinking efficacy of deinking agents containing the product or the blend,and purchased from market was tested and compared.Results showed that the synthesis process conditions,which shows the optimal deinking effect are as follows:n(NaOL)∶n(SMAS)∶n(AA)=1∶1∶3;reaction temperature,85 ℃;reaction time,5 h;w(APS)=2.5% (the mass of total reactants).When the blended deinking agent is formulated in accordance with m(NaOL-AA-SMAS)∶m(AEO₉)=2∶1,the brightness of the deinked waste paper can reach to 71.9% and the residual ink concentration is 42.3 mm²/m².

Key words: deinking agent, sodium oleate, acrylic acid, sodium methallyl sulfonate, copolymer, brightness, residual ink concentration