| 摘要 |
A controlled-release, delivery composition which comprises (A) a crosslinked copolymer, capable of swelling in ethanol to give a swollen copolymer containing at least 40% by weight of ethanol, and capable of swelling in water to give a swollen copolymer containing no more than 20% by weight of water, where the swelling ratio (% ethanol: % water) is 2:1 to 22:1, which comprises the copolymerization product of (a) 50 to 99 % by weight of said copolymer of a water-insoluble monoolefinic monomer or (a) with 0 to 45 % weight of total monomers of a water-soluble monoolefinic monomer, with (b) 50 to 1 % by weight, but not more than 20 mol % of a divinyl or polyvinyl crosslinking agent; and (B) an effective amount of an active agricultural ingredient is useful for the controlled and prolonged release of said ingredient. |
