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To promote the application of lignin in Pickering emulsions, the influences of six lignin particles with different hydrophobicity on the emulsifying and stabilizing performances for oil phases with different polarity to form oil in water Pickering emulsions were investigated. The results showed that the best emulsification performance was achieved when the three-phase (oil–water–lignin particle) contact angle was close to 90°. Alkyl-bridged lignin particles with stronger hydrophobicity have a better emulsification effect on cyclohexane with less polarity, while carboxymethylated lignin particles with stronger hydrophilicity have better emulsification effect on n-heptanol with higher polarity. Furthermore, the stability of Pickering emulsions can be improved by appropriately increasing the surface charge and decreasing the particular size of the lignin particles. [ABSTRACT FROM AUTHOR]

Improving the thermal storage stability of nanosuspension concentrate (SC) prepared from low-melting-point pesticide is a recognized problem. In this work, using pyraclostrobin as the raw material, 25 wt% of pyraclostrobin nano-SC was prepared through a water-based grinding method, and the optimal grinding conditions were obtained as follows: a grinding time of 23 h, D-3911 as dispersant and a dispersant dosage of 12 wt%. The pyraclostrobin nano-SC D90 size prepared based on this best formula was 216 nm. Adding glycerin could improve the stability of nano-SC at room temperature, but its thermal storage stability was still poor. For this problem, sodium lignosulfonate and cetyltrimethylammonium bromide (NaLS/CTAB) colloidal spheres were prepared through electrostatic and hydrophobic self-assembly and characterized. The delamination and precipitation of nano-SC can be significantly improved by adding an appropriate amount of colloidal spheres, and the nano-SC D90 size decreased from 2726 to 1023 nm after 7 days of thermal storage. Farmland experiments indicated the control efficiency of pyraclostrobin nano-SC against flowering cabbage downy mildew disease was about 30% higher than that of SC. Especially after adding the wetting agent, the effect of nano-SC could be comparable to that of commercial Kairun (currently the best pyraclostrobin formulation in the world). [ABSTRACT FROM AUTHOR]