Cross-linked modified waxes for controlled release fertilizers
AssigneeAgrium Advanced Technologies
InventorsGARRARD LEE HARGROVE, Sriramakrishna Maruvada, Robert Scott Wilson, Nick Peter Wynnyk, Baozhong Xing
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Abstract
A controlled release fertilizer material comprising a particulate plant nutrient surrounded by, a coating of a mixture including an isocyanate and a polyol, and further comprising a modified wax that may include a polyhydroxyt compound in which the wax and/or the polyhydroxyl compound are cross-linked with a sulfur or oxygen or a peroxide cross-linking moiety. In certain embodiments, the wax and polyhydroxyl compound are cross-linked at unsaturated sites in the wax or polyhydroxyl compound using heat, UV or ionizing radiation.
Claims20
A controlled release fertilizer composition including a plant nutrient coated with a reaction product of a mixture including an isocyanate and a polyol and comprising a modified wax, wherein the modified wax is cross-linked.
A process of producing a controlled release fertilizer comprising the steps of:
- contacting a wax, a polyhydroxyl compound or a mixture of a wax and a polyhydroxyl compound with cross-linking agent comprising sulfur, oxygen, and/or a peroxide cross-linking moiety to provide a modified wax;
- contacting a particulate plant nutrient with a mixture comprising the modified wax, an isocyanate, and a polyol to provide a coated particulate plant nutrient, and
- curing the coated particulate plant nutrient to provide the controlled release fertilizer.
A process of producing a controlled release fertilizer comprising the steps of:
- contacting a mixture of castor oil and an olefin wax with a cross-linking agent comprising sulfur, oxygen, and/or a peroxide moiety to produce a cross-linked mixture of castor oil and the olefin wax, wherein the castor oil and the olefin wax are cross-linked with either sulfur, oxygen, or the peroxide cross-linking moiety;
- contacting a particulate plant nutrient with a mixture comprising the cross-linked castor oil and olefin wax, a polyol and an isocyanate to provide a coated particulate plant nutrient, and curing the coated particulate plant nutrient to provide the controlled release fertilizer
Dependencies are inferred from the claim text.