Development of novel ionic liquids based on bentazone

Bentazone is one of the widely used herbicides for controlling sedges and broad-leaf weeds. Due to its high mobility in soils, bentazone has been frequently found among the contaminants detected in surface and ground water and poses a potential threat to aquatic organisms by runoff and leaching. In this work, novel herbicidal ionic liquids (HILs) based on bentazone with four typical cations were synthesized and characterized. The physicochemical properties (water solubility, surface activity, leaching and soil adsorption) and herbicidal activity of HILs were investigated. The result showed that the water solubility of HILs was reduced along with the increasing length of alkyl chains in cations. Compared with bentazone sodium, HILs showed higher adsorption capacity, weaker mobility, and excellent surface activity and Pyr-1 substantially performed higher efficacy under field condition. With high activity of weed control and fascinating physicochemical properties, HILs can reduce the risk of bentazone in aquatic environment and they will be applied widely in the future. (c) 2015 Elsevier Ltd. All rights reserved.