The sodium lignosulphonate polyethenoxy ether (SL-PEG) was prepared by electrophilic substitution reaction using sodium lignosulphonate (SL) and polyethylene glycol (PEG600).The chemical structure of SL-PEG was characterized and the weight-average molecular weight of SL-PEG was up to 32900

because of the grafting of many polyethenoxy ether units.The grafting reaction was found to occur at phenolic hydroxy of SL

thus the phenolic hydroxy contents of SL-PEG reduced from 1.17 to 0.30 mmolg-1.Subsequently

the lignin-based cationic-anionic surfactant (CA-SL) was prepared via electrostatic self-assembled method combining SL-PEG with cetyl trimethyl ammonium bromide (CTAB).The surface activity and aqueous solution behaviour of CA-SL was studied

the result showed that the CA-SL aqueous solution presents far lower surface tension (minimum to 38.75 mNm-1) and critical aggregation concentration (0.0050~0.0065 gL-1) than SL.In order to investigate the dispersing and stabilizing properties of CA-SL

the CA-SL was used as dispersants to prepare imidacloprid and dimethomorph suspension concentrates.The results indicated that the CA-SL has good grinding and dispersion effect

and these two suspension concentrates exhibit good stability during the heat storage process

owing to its excellent ability to restrain the creaming and particle coarsening effectively.