| 摘要 |
Plant nutrients that are released in soil over a controlled period of time are comprised of plant nutrient particles containing urea and on the surface of the particles a water insoluble, biodegradable, interpenetrating polymer network comprised of a biuret, a urethane and tung oil; more specifically, an interpenetrating network comprised of the reaction product of the urea and an isocynate reactive with urea, the reaction product of the isocyanate and an alcohol reactive with isocyanate to form a urethane, and the reaction product of the urethane and tung oil. A method of making the controlled release plant nutrient conveniently and economically is also disclosed. |
