Preparation of slow release nanopesticide microspheres from benzoyl lignin

Abstract In this paper, benzoyl lignin (BzL) was prepared from alkali lignin (AL) by hydrophobic modification, and then nanospheres (BzLCN) were prepared by the reverse solvent method of BzL and λ-cyhalothrin (λC), while BzL served as the carrier material. BzLCN particle size was decreasing with the increasing amount of BzL reaching the minimum diameters of 90–100 nm. The emulsifier 600 # further reduces the particle size to about 40 nm. The prepared BzLCN had a remarkable slow release property, while the emulsifier increased the release rate. The formation mechanism of BzLCN showed that BzL mainly contains carboxyl groups and acts as a carrier material. BzL tends to aggregate on the surface of BzLCN nanospheres and provides negative charge and contributes to maintaining its stability. The hydrophobic λC moves toward the interior of the nanospheres. The emulsifier adsorbed on the surface of BzLCN is a steric hindrance and enhances the stability of BzLCN.