Wetting of water repellent soil by low HLB EO/PO block copolymers and enhancing solubility of same

Abstract

Water repellent soil is treated with low concentrations of EO/PO block copolymer having an HLB value of less than or equal to 2; an average molecular weight of greater than 3,000; and a percent hydrophile of 10 in order to rapidly increase the wetting rate of the water repellent soil.

1 . A process for increasing the wetting rate of water repellent soil which comprises the steps of: 
 i) preparing an aqueous wetting agent composition consisting of 
 a) an ethylene oxide-propylene oxide block copolymer (A) wherein the copolymer has an IT value of less than or equal to 2; an average molecular weight of greater than 3,000; and a percent hydrophile of less than or equal to 10; and  
 b) water; and  
   ii) intimately contacting water repellent soil with an amount of said wetting agent composition such that the EO/PO block copolymer (A) is present in the soil in an amount that, were it to be the only wetting rate increasing active present in the soil, it would provide a measurable increase in the wetting rate of the soil.    
     
     
         2 . The process of  claim 1  wherein the total concentration of the block copolymer (A) in the wetting agent composition is from 200,000 ppm to 2 ppm.  
     
     
         3 . The process of  claim 1  wherein the ethylene oxide-propylene oxide block copolymer (A) is selected from the group consisting of: 
 i) straight block polymeric glycols obtained by the addition of ethylene oxide (EO) on a condensation product of propylene oxide (PO) with propylene glycol;    ii) reverse block polymeric glycols obtained by the addition of propylene oxide (PO) on a condensation product of ethylene oxide (EO) with ethylene glycol;    iii) tetra functional block copolymers obtained by the sequential addition of initially propylene oxide and then ethylene oxide to ethylene diamine; and    iv) tetra functional reverse block copolymers obtained by the sequential addition of initially ethylene oxide and then propylene oxide to ethylene diamine.    
     
     
         4 . The process of  claim 1  wherein the composition consists of 
 a) an ethylene oxide—propylene oxide block copolymer (A) wherein the copolymer has an HLB value of less than or equal to 2; an average molecular weight of greater than 3,000; and a percent hydrophile of less than or equal to 10;    b) an ethylene-propylene oxide block copolymer (B) having an HLB value greater than 2 and an average molecular weight of from 2,000 to 8,000; and    c) water.    
     
     
         5 . The process of  claim 4  wherein the composition consists of 
 a) from 99 to 1 parts by weight copolymer (A); and    b) from 1 to 99 parts by weight copolymer (B) wherein the parts by weight is based on the total weight of copolymers (A) and (B).    
     
     
         6 . A process for increasing the wetting rate of water repellent soil which comprises the steps of: 
 i) preparing an aqueous wetting agent composition consisting of 
 a) an ethylene oxide—propylene oxide block copolymer (A) wherein the copolymer has an HLB value of less than or equal to 2; an average molecular weight of greater than 3,000; and a percent hydrophile of less than or equal to 10;  
 b) an alkylpolyglycoside; and  
 c) water, and  
   ii) intimately contacting water repellent soil with an amount of said wetting agent composition such that the EO/PO block copolymer (A) is present in the soil in an amount that, were it to be the only wetting rate increasing active present in the soil, it would provide a measurable increase in the wetting rate of the soil.    
     
     
         7 . The process of  claim 6  wherein the composition consists of 
 a) from 99 to 1 parts by weight copolymer (A); and    b) from 1 to 99 parts by weight alkylpolyglycoside wherein the parts by weight is based on the total weight of copolymer (A) and the alkylpolyglycoside.    
     
     
         8 . A process for increasing the wetting rate of water repellent soil which comprises the steps of: 
 i) preparing an aqueous wetting agent composition consisting of 
 a) an ethylene oxide—propylene oxide block copolymer (A) wherein the copolymer has an HLB value of less than or equal to 2; an average molecular weight of greater than 3,000; and a percent hydrophile of less than or equal to 10;  
 b) an ethylene-propylene oxide block copolymer (B) having an HLB value greater than 2 and an average molecular weight of from 2,000 to 8,000;  
 c) an alkylpolyglycoside; and  
 d) water; and  
   ii) intimately contacting water repellent soil with an amount of said wetting agent composition such that the EO/PO block copolymer (A) is present in the soil in an amount that, were it to be the only wetting rate increasing active present in the soil, it would provide a measurable increase in the wetting rate of the soil.    
     
     
         9 . The process of  claim 8  wherein the composition consists of 
 a) from 98 to 1 parts by weight copolymer (A);    b) from 1 to 98 parts by weight copolymer (B); and    c) from 1 to 98 parts by weight alkylpolyglycoside    wherein the total parts by weight is 100 and is based on the total weight of copolymer (A); copolymer (B); and the alkylpolyglycoside.    
     
     
         10 . A process for increasing the wetting rate of water repellent soil which comprises the steps of: 
 i) preparing a solid granular or powder wetting agent composition consisting of an ethylene oxide-propylene oxide block copolymer (A) wherein the copolymer has an HLB value of less than or equal to 2; an average molecular weight of greater than 3,000; and a percent hydrophile of less than or equal to 10; and    ii) intimately contacting water repellent soil with said solid wetting agent composition such that the EO/PO block copolymer (A) is present in the soil in an amount that, were an aqueous composition were to be prepared consisting only of water and said copolymer (A) and intimately applied to said soil such that the copolymer (A) concentration in said soil is the same as when the solid wetting agent composition is applied, said copolymer (A) amount would provide a measurable increase in the wetting rate of the soil.    
     
     
         11 . A process for increasing the wetting rate of water repellent soil which comprises the steps of: 
 i) preparing a solid granular or powder wetting agent composition containing an ethylene oxide-propylene oxide block copolymer (A) wherein the copolymer has an HLB value of less than or equal to 2; an average molecular weight of greater than 3,000; and a percent hydrophile of less than or equal to 10;    ii) adding said solid wetting agent composition to water to form an aqueous wetting agent composition; and    iii) intimately contacting water repellent soil with an amount of said aqueous wetting agent composition such that the EO/PO block copolymer (A) is present in the soil in an amount that, were it to be the only wetting rate increasing active present in the soil, it would provide a measurable increase in the wetting rate of the soil.