Copolymer comprising units of type a deriving from carboxylic acid monomers and units of type b deriving from sulfonic acid monomers

Abstract

The present invention relates to a copolymer comprising units of type A deriving from carboxylic acid monomers and units of type B deriving from sulfonic acid monomers, said units of type A and B representing more than 80 mol % of the total moles of units in the copolymer,characterized in that it comprises at least:one first block formed of at least 95 mol % of units of type A and having a degree of polymerization DP1 comprised between 5 and 150; andone second block formed of at least 95 mol % of units of type A and B with a molar ratio of units of type A to units of type B greater or equal to 1, wherein said units of type A and units of type B are statistically distributed, said second block having a degree of polymerization DP2 such that DP2/DP1≥1.It also relates to new detergent compositions comprising such a copolymer, and to the use of this copolymer in a detergent composition, especially an ADW composition, to prevent, limit or eliminate the filming phenomena.

1 . A copolymer comprising units of type A deriving from carboxylic acid monomers and units of type B deriving from sulfonic acid monomers, said units of type A and B representing more than 80 mol % of the total moles of units in the copolymer,
 characterized in that it comprises at least:   one first block formed of at least 95 mol % of units of type A and having a degree of polymerization DP 1  comprised between 5 and 150; and   one second block formed of at least 95 mol % of units of type A and B with a molar ratio of units of type A to units of type B being greater or equal to 1, wherein said units of type A and units of type B are statistically distributed, said second block having a degree of polymerization DP 2  such that DP 2 /DP 1 ≥1.   
     
     
         2 . The copolymer according to  claim 1 , wherein the ratio DP 2 /DP 1  is less than or equal to 1,000. 
     
     
         3 . The copolymer according to  claim 1  wherein the first block has a degree of polymerization DP 1  greater than or equal to 10. 
     
     
         4 . The copolymer according to  claim 1  wherein the second block has a degree of polymerization DP 2  less than or equal to 2,000. 
     
     
         5 . The copolymer according to  claim 1  wherein the molar ratio of units of type A to units of type B in the second block ranges from 50/50 to 90/10. 
     
     
         6 . The copolymer according to  claim 1  wherein units of type A derive from monomers selected from the group consisting of acrylic acid, methacrylic acid, ethacrylic acid, alpha-chloro-acrylic acid, bromo acrylic acid, bromomethyl acrylic acid, alpha-cyano acrylic acid, beta methyl-acrylic acid, alpha-phenyl acrylic acid, beta-acryloxy propionic acid, beta-carboxyethyl acrylic acid, sorbic acid, alpha-chloro sorbic acid, angelic acid, cinnamic acid, p-chloro cinnamic acid, beta-styryl acrylic acid, itaconic acid, maleic acid, citraconic acid, mesaconic acid, glutaconic acid, aconitic acid, fumaric acid, vinyl benzoic acid, pentenic acid, propyl acrylic acid, acetamido acrylic acid, maleimido propyl carboxylic acid and mixtures thereof. 
     
     
         7 . The copolymer according to  claim 1  wherein said units of type A of the first block are identical to said units of type A of the second block. 
     
     
         8 . The copolymer according to  claim 1  wherein units of type A of the first block and/or the second block derive from acrylic acid monomer. 
     
     
         9 . The copolymer according to  claim 1  wherein units of type B derive from monomers selected from the group consisting of acrylamido-2-methylpropanesulfonic acid, 2-methacrylamido-2-methylpropanesulfonic acid, 3-methyacrylamido-2-hydroxypropanesulfonic acid, (meth)allylsulfonic acid, 1-allyloxy-2-hydroxypropane sulfonic acid, allyloxybenzene sulfonic acid, (meth)allyloxybenzensulfonic acid, 2-hydroxy-3-(2-propenyloxy)propanesulfonic acid, 2-methyl-2-propene-1-sulfonic acid, styrene sulfonic acid, vinylsulfonic acid, 3-sulfopropyl acrylate, 3-sulfopropyl methacrylate, sulfomethylacrylamid, sulfomethylmethacrylamid, water soluble salts thereof, and mixtures thereof. 
     
     
         10 . The copolymer according to  claim 1  wherein units of type B derive from 2-acrylamido-2-methylpropanesulfonate monomer or sodium vinyl sulfonate monomer. 
     
     
         11 . The copolymer according to  claim 1  wherein said units of type A derive from acrylic acid monomer and said units of type B derive from 2-acrylamido-2-methylpropanesulfonate monomer. 
     
     
         12 . The copolymer according to  claim 1  comprises a diblock copolymer consisting of one first block and one second block as defined in  claim 1 . 
     
     
         13 . The copolymer according to  claim 1  wherein said diblock copolymer consists of:
 one first block deriving from acrylic acid monomers with a degree of polymerization DP 1  comprised around 60; and 
 one second block that is a statistical block deriving from acrylic acid (AA) and 2-acrylamido-2-methylpropanesulfonate (AMPS) monomers with a molar ratio of AA units to AMPS units comprised between 50/50 and 80/20, said second block having a degree of polymerization DP2 comprised between 50 and 250. 
 
     
     
         14 . A detergent composition comprising at least one copolymer according to  claim 1 . 
     
     
         15 . The copolymer according to  claim 1 , wherein said composition comprises from 0.001 to 10% by weight of said copolymer in respect to the total weight of the composition. 
     
     
         16 . A method of preventing, limiting or eliminating filming phenomena comprising adding to at least one copolymer according to  claim 1  a detergent composition, wherein the detergent composition is an automatic dishwashing detergent composition. 
     
     
         17 . A diblock copolymer pAA-b-(pAA/AMPS 75/25) comprising units of type A deriving from acrylic acid monomers and units of type B deriving from acrylic acid and 2-acrylamido-2-methylpropane sulfonate monomers with a molar ratio of type A units to type B units of 50/50. 
     
     
         18 . The copolymer according to  claim 17 , wherein the second block has a degree of polymerization DP 2  between 60 and 80.