The invention discloses a long-acting molluscicidal composition and a preparation method thereof, and belongs to the technical field of molluscicidal preparations, the long-acting molluscicidal composition and the preparation method thereof are characterized in that firstly, hydroxyl at the
tail end of
polyethylene glycol
monomethyl ether is subjected to
esterification reaction to obtain a hydrophilic
polyethylene glycol-based polymeric precursor, then the precursor is grafted with hydrophobic
benzyl methacrylate to obtain an amphipathic block
copolymer, and then the amphipathic block
copolymer is subjected to
polymerization reaction to obtain the long-acting molluscicidal composition. The preparation method comprises the following steps: preparing a
niclosamide solution, constructing a nano slow-release carrier through
hydrazide modification, stably entrapping
abamectin to form a high-dispersion nano slow-release medicament, and carrying out composite solubilization on the indissolvable
niclosamide by using an outer hydrophilic and inner hydrophobic cavity structure of 2-hydroxypropyl-beta-
cyclodextrin, then, the dual-
drug-loading
system and a food calling component are jointly introduced into a
sodium alginate-
starch gel skeleton and are extruded and formed, so that the preparation forms an effective
drug effect unit which stably exists at the bottom of a
water body, and therefore, an effective killing concentration can be quickly established in a complex
water environment, and
drug effect output can be maintained for a long time; the method is suitable for continuous and efficient prevention and control of
pomacea canaliculata in rice fields and
open water areas.