Preparation of lignin/polyethylene glycol film-forming agent and its application in chlorantraniliprole 5% flowable concentrate for seed coating (FS)

Five Lignin/Polyethylene Glycol (L-PEG) film-forming agents with different lignin contents were prepared using industrial Alkali Lignin (AL) and Polyethylene Glycol (PEG) as the main raw materials. FI-IR and 1H NMR analysis demonstrated the introduction of large amounts of polyethylene chains in lignin molecules. The prepared L-PEGs could be dispersed in water to form a stable nanoemulsion with a particle size of 131–232 nm and a zeta potential of − 27.22~− 38.64 mV. After L-PEGs drying into film, the obtained films can swell rapidly in water, with a swelling rate of 183.3–257.6%. The swollen wet film dissolved slowly in water with a dissolution rate of 42.3–57.1% in 14 days. The 5% flowable concentrate for seed coating (FS) of chlorantraniliprole was prepared by using L-PEG as a film-forming agent. The storage stability at elevated temperature experiment showed that the FS had good storage stability. The coating experiment showed that the FS had good coating performance, with film forming time less than 4 min, coating uniformity higher than 93.3%, and shedding rate lower than 7.67%. The pot experiment showed that the germination percentage of coated maize (Zea mays L.) seeds increased from 86.67% to over 93.33%, which could promote the growth of seedlings.