| abstract |
Compositions of and a method for preparing polymeric formulations that gradually, continuously and uniformly release various compounds over a long period of time in ionic form that are well recognized as essential to the growth of agricultural commodities. The compounds, such as inorganic salts of varying water solubilities, are monolithically incorporated into a thermoplastic matrix containing porosigens to regulate the release rate. Said porosigens can be the low or moderate soluble salts such as the carbonate, bicarbonates, sulfates, phosphates, nitrates, etc.; of the alkali metals, the alkaline earths or ammonium. Upon exposure to moisture, water ingress into the dispensing pellet removes said porosigen through dissolution processes thus creating a porous network permitting water contact with the incorporated nutrient molecules and their gradual egress in said water over a period of time such as for about a couple of months to four years, or longer. |