Quick drying polymeric coating

Abstract

Improved agriculturally useful products are provided, including solid materials such as nitrogenous fertilizers (e.g., urea), together with a polycarboxylated polymer selected from the group consisting of a salts of copolymers containing individual quantities of maleic and itaconic moieties. The polymer composition also includes from about 10-60% by weight of an organic drying agent such as a lower alcohol which enhances the quick drying properties thereof. The compositions may also include an amount of boron, and bimodal vinylic polymer made up of quantities of high and low molecular weight (MW) vinylic polymers such as PVA.

1 . A polymer-containing aqueous composition adapted for application to agriculturally useful solid products, said polymer-containing composition including a copolymer containing individual quantities of maleic and itaconic moieties, and an organic compound drying agent selected from the group consisting of organic alcohols and ketones and operable to enhance the vaporization of water when the composition is applied to said solid product. 
   
   
       2 . The polymer-containing composition of  claim 1 , said copolymer containing from about 10-90% maleic moieties, and from about 90-10% itaconic moieties. 
   
   
       3 . The polymer-containing composition of  claim 1 , said copolymer consisting essentially of said maleic and itaconic moieties. 
   
   
       4 . The polymer-containing composition of  claim 1 , said drying agent selected from the group consisting of C1-C4 alcohols. 
   
   
       5 . The polymer-containing composition of  claim 1 , said organic drying agent being present at a level of from about 5-60% by weight. 
   
   
       6 . The polymer-containing composition of  claim 1 , said copolymer being in partial salt form and having at least about 93% itaconic and maleic moieties. 
   
   
       7 . The polymer-containing composition of  claim 1 , said composition comprising from about 20-70% by weight of said copolymer in partial salt form, from about 5-60% by weight methanol, and from about 10-50% by weight water. 
   
   
       8 . The polymer-containing composition of  claim 7 , said copolymer salt being present at a level of from about 30-60% by weight, from about 30-50% by weight methanol, and from about 10-25% by weight water. 
   
   
       9 . The polymer-containing composition of  claim 1 , including from about 0.5-5% by weight boron as boric acid. 
   
   
       10 . The polymer-containing composition of  claim 9 , including an amount of bimodal vinyl polymer therein, said bimodal vinyl polymer including individual high and low molecular weight vinyl polymer fractions. 
   
   
       11 . The polymer-containing composition of  claim 10 , said bimodal vinyl polymers comprising low MW PVA having a weight averaged molecular weight Mw of from about 13,000-23,000, and high MW PVA having a weight averaged molecular weight Mw of about 145,000 and above, said low MW PVA being present in an amount greater than said high MW PVA. 
   
   
       12 . The polymer-containing composition of  claim 11 , the ratio of said high MW PVA to said low MW PVA being from about 1:2 to 1:20. 
   
   
       13 . The polymer-containing composition of  claim 12 , said ratio being from about 1:4 to 1:12. 
   
   
       14 . The polymer-containing composition of  claim 1 , adapted for application to a solid, nitrogenous fertilizer, said polymer-containing composition comprising:
 (1) from about 20-50% by weight of maleic-itaconic copolymer, in the form of a partial salt and having at least about 93% itaconic and maleic moieties therein;   (2) volatile organic solvent present at a level of from about 5-60% by weight;   (3) low MW PVA at a level of from about 0.5-10% by weight;   (4) high MW PVA at a level of from about 0.1-4% by weight;   (5) a ratio of high MW PVA to low MW PVA of from about 1:2 to 1:20;   (6) boric acid at a level of from about 0.5-5% by weight; and   (7) water.   
   
   
       15 . The polymer-containing composition of  claim 14 , wherein:
 (1) said maleic-itaconic copolymer consists essentially of maleic and itaconic moieties and is present as a partial calcium salt with carboxylate substitution by calcium at a level of from about 1-35%, and in an amount of from about 35-45% by weight;   (2) said organic solvent comprises methanol and is present at a level of from about 35-50% by weight;   (3) said low MW PVA is present at a level of from about 2-6% by weight and has a weight averaged molecular weight Mw of from about 13,000-23,000;   (4) said high MW PVA is present at a level of from about 0.2-2% by weight and has a weight averaged molecular weight Mw of from about 146,000-186,000;   (5) said ratio is from about 1:4 to 1:12;   (6) said boric acid is present at a level of from about 2-4% by weight; and   (7) water forms the balance of said composition.   
   
   
       16 . A fertilizer product comprising:
 a quantity of a solid fertilizer; and   a polymer-containing aqueous composition applied to said fertilizer, said polymer-containing composition including a copolymer containing individual quantities of maleic and itaconic moieties, and an organic compound drying agent selected from the group consisting of organic alcohols and ketones and operable to enhance the vaporization of water when the composition is applied to said solid product.   
   
   
       17 . The fertilizer product of  claim 16 , said fertilizer being a nitrogenous fertilizer. 
   
   
       18 . The fertilizer product of  claim 17 , said fertilizer selected from the group consisting of urea, ammonium sulfate, ammonium nitrate, and mixtures thereof in the form of granules or prills, said composition applied to the surface of said fertilizer at a level of from about 0.1-1 gallons of said polymer-containing composition per ton of said solid fertilizer. 
   
   
       19 . The fertilizer product of  claim 16 , said fertilizer being urea, said composition comprising:
 (1) from about 20-50% by weight of maleic-itaconic copolymer, in the form of a partial salt and having at least about 93% itaconic and maleic moieties therein;   (2) volatile organic solvent present at a level of from about 5-60% by weight;   (3) low MW PVA at a level of from about 0.5-10% by weight;   (4) high MW PVA at a level of from about 0.1-4% by weight;   (5) a ratio of high MW PVA to low MW PVA of from about 1:2 to 1:20;   (6) boric acid at a level of from about 0.5-5% by weight; and   (7) water.   
   
   
       20 . A method of fertilizing soil comprising the step of applying the fertilizer product of  claim 16  to soil.