CONTINUOUS PREPARATION OF POLYURETHANES OR POLYUREAS

Abstract

The invention relates to the field of associative thickeners, and more particularly to associative thickeners of the HEUR type, used in aqueous formulations. In particular, the invention relates to a method for the continuous preparation of HEUR-type associative thickeners by reactive extrusion. These products are intended to be used in aqueous formulations

Claims

1. A method for preparing a thickening composition, the method comprising: continuously preparing a hydrophilic polymer (P) by a reactive extrusion of at least one water-soluble polyalkylene glycol (A) and at least one product (B), and mixing the hydrophilic polymer (P) in at least one solvent, wherein the at least one water-soluble polyalkylene glycol (A) chosen among is at least one selected from the group consisting of a polyethylene glycol, a polyethylene glycol-polypropylene glycol copolymer comprising at most 40% by weight of polypropylene glycol, and a polyethylene glycol-polybutylene glycol copolymer comprising at most 20% by weight of polybutylene glycol; and the at least one product (B) comprises an associative group and an isocyanate group, and the at least one product (B) is at least one selected from the group consisting of: (a) a compound (B1) of formula (I):
R—N═C═O  (I) wherein R represents a straight, branched, or cyclic, saturated, unsaturated, or aromatic hydrocarbon group comprising from 6 to 40 carbon atoms, (b) a combination of a diisocyanate (B3) and a compound (B2) of formula (II):
R′-(EO).sub.n—(PO).sub.m—(BO).sub.p—X  (11) wherein: R′ represents a straight, branched, or cyclic, saturated, unsaturated, or aromatic hydrocarbon group comprising from 6 to 40 carbon atoms, (EO) represents an ethoxylene group, (PO) represents a propoxylene group, (BO) represents a butoxylene group, n represents a real number comprised between 0 and 150, m represents a real number comprised between 0 and 150, p represents a real number comprised between 0 and 150, a sum of n+m+p represents a real number comprised between 0 and 150, and X represents a chemical group carrying a labile hydrogen that optionally reacts with an isocyanate group, (c) a product resulting from a prior condensation of the diisocyanate (B3) and the compound (B2) of formula (II), and (d) a combination of the diisocyanate (B3) and the compound (B1) of formula (I).

2. The method according to claim 1, wherein the at least one water-soluble polyalkylene glycol (A) is a polyalkylene glycol with a weight-average molecular mass (Mw) ranging from 1,000 to 40,000 g/mol.

3. The method according to claim 1, wherein the at least one product comprises the compound of (B2) of formula (II), and X is an alcohol group or an amine group.

4. The method according to claim 1, wherein the at least one product comprises the diisocyanate (B3), and the diisocyanate (B3) is at least one selected from the group consisting of 1,4-butane diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, isophorone diisocyanate, 1,3- and 1,4-cyclohexane diisocyanate, methylene bis(4-cyclohexylisocyanate), 2,6-toluene diisocyanate, 2,4-toluene diisocyanate, 2,2′-diphenylmethylene diisocyanate, 4,4′-diphenylmethylene diisocyanate, 2,4′-diphenylmethylene diisocyanate, 4,4′-dibenzyl diisocyanate, 2,4′-dibenzyl diisocyanate, m-xylylene diisocyanate, 1-methyl-2,4-diisocyanatocyclohexane and its combination with 1-methyl-2,6-diisocyanatocyclohexane, tetramethylxylene diisocyanate (TMXDI), and hexane trimethyl-1,6-diisocyanate.

5. The method according to claim 1, wherein the reactive extrusion is a reactive extrusion of the at least one water-soluble polyalkylene glycol (A), the at least one product (B) and at least one cross-linking compound (C).

6. The method according to claim 1, wherein the reactive extrusion is carried out in the presence of a catalyst.

7. The method according to claim 1, wherein the hydrophilic polymer (P) is prepared by reactive extrusion of: (A) at least 55% of the at least one water-soluble polyalkylene glycol (A); (B) from 5 to 45% of the at least one product (B); and (C) from 0 to 10% of cross-linking compound (C), percentages being expressed by weight relative to a total weight of compounds introduced.

8. The method according to claim 1, wherein the at least one solvent is water and/or an organic solvent.

9. The method according to claim 1, wherein, the mixing is a mixing the water-soluble polymer (P) in the at least one solvent with at least one additive chosen among selected from the group consisting of an amphiphilic compound, a polysaccharide derivative, a hydrotropic compound, an antifoaming agent, and a biocide agent.

Description

EXAMPLE 1

Test 1

[0169] This example illustrates the production of an HEUR by addition of polyethylene glycol (PEG), of ethoxylated cardanol (CASnumber: 37330-39-5) with isophorone diisocyanate (IPDI) in the presence of a catalyst.

[0170] The polyethylene glycol used comprises approximately 230 repeating units, the length of the ethoxylate chain of the cardanol is approximately 4 units of ethylene oxide, and the catalyst used is dibutyltin dilaurate (DBTDL).

[0171] The PEG/ethoxylated cardanol/DBTDL mixture is placed in a sealed tank heated to 90° C. under vacuum and dehydrated until a water content of less than 800 ppm is obtained. This tank is then inerted with nitrogen.

[0172] The IPDI is placed in a sealed tank heated to 60° C. and inerted with nitrogen.

[0173] In this example, area 1 is heated to 25° C. The other 15 areas are heated to 120° C. The residence time of the reaction medium in the extruder is between 8 and 10 minutes for a flow rate of 3.05 kg/h (IPDI 0.18 kg/h; PEG 2.6 kg/h; ethoxylated cardanol 0.27 kg/h).

[0174] The product obtained at the extruder outlet is in the form of a molten resin. It is formulated directly at the outlet of the die in a water/cosolvent mixture (OXO C10 alcohol ethoxylates—Surfaline Ox1008 from Arkema) such that the final formulation contains 30% by weight of polyurethane base, 20% by weight of cosolvent and 50% by weight of water. A portion of the unformulated resin is preserved in order to measure the MVR (melt volume rate).

MVR(100° C./216 kg)=45 cm.sup.3/10 min.

Test 2

[0175] This example illustrates the production of an HEUR by addition of polyethylene glycol, of ethoxylated cardanol with IPDI in the presence of a catalyst.

[0176] The polyethylene glycol used comprises approximately 230 repeating units, the length of the ethoxylate chain of the cardanol is approximately 4 units of ethylene oxide and the catalyst used is dibutyltin dilaurate.

[0177] The PEG/ethoxylated cardanol/DBTDL mixture is placed in a sealed tank heated to 90° C. under vacuum and dehydrated until a water content of less than 800 ppm is obtained. This tank is then inerted with nitrogen.

[0178] The IPDI is placed in a sealed tank heated to 60° C. and inerted with nitrogen. In this example, area 1 is heated to 25° C. The other 15 areas are heated to 120° C.

[0179] The residence time of the reaction medium in the extruder is between 5 and 7 minutes for a flow rate of 4.58 kg/h (IPDI 0.27 kg/h; PEG 3.9 kg/h; ethoxylated cardanol 0.41 kg/h).

[0180] The product obtained at the extruder outlet is in the form of a molten resin. It is formulated directly at the outlet of the die in a water/cosolvent mixture (Surfaline Ox1008 from Arkema) such that the final formulation contains 30% by weight of polyurethane base, 20% by weight of cosolvent and 50% by weight of water. A portion of the unformulated resin is preserved in order to measure the MVR (melt volume rate).

MVR(100° C./2.16 kg)=62 cm.sup.3/10 min.

Test 3

[0181] This example illustrates the production of an HEUR by addition of polyethylene glycol, of ethoxylated cardanol with IPDI in the presence of a catalyst.

[0182] The polyethylene glycol used comprises approximately 230 repeating units, the length of the ethoxylate chain of the cardanol is approximately 4 units of ethylene oxide and the catalyst used is dibutyltin dilaurate.

[0183] The PEG/ethoxylated cardanol/DBTDL mixture is placed in a sealed tank heated to 90° C. under vacuum and dehydrated until a water content of less than 800 ppm is obtained. This tank is then inerted with nitrogen.

[0184] The IPDI is placed in a sealed tank heated to 60° C. and inerted with nitrogen.

[0185] In this example, area 1 is heated to 25° C. The other 15 areas are heated to 120° C. The residence time of the reaction medium in the extruder is between 11 and 14 minutes for a flow rate of 2.29 kg/h (IPDI 0.14 kg/h; PEG 1.95 kg/h; ethoxylated cardanol 0.20 kg/h).

[0186] The product obtained at the extruder outlet is in the form of a molten resin. It is formulated directly at the outlet of the die in a water/cosolvent mixture (Surfaline Ox1008 from Arkema) such that the final formulation contains 30% by weight of polyurethane base, 20% by weight of cosolvent and 50% by weight of water. A portion of the unformulated resin is preserved in order to measure the MVR (melt volume rate).

MVR(100° C./2.16 kg)=21 cm.sup.3/10 min.

Test 4 This example illustrates the production of an HEUR by addition of polyethylene glycol, of ethoxylated cardanol with toluene diisocyanate (TDI 80/20) in the presence of a catalyst.

[0187] The polyethylene glycol used comprises approximately 230 repeating units, the length of the ethoxylate chain of the cardanol is approximately 4 units of ethylene oxide and the catalyst used is dibutyltin dilaurate.

[0188] The PEG/ethoxylated cardanol/DBTDL mixture is placed in a sealed tank heated to 90° C. under vacuum and dehydrated until a water content of less than 800 ppm is obtained. This tank is then inerted with nitrogen.

[0189] The TDI is placed in a sealed tank heated to 60° C. and inerted with nitrogen.

[0190] In this example, area 1 is heated to 25° C. The other 15 areas are heated to 120° C. The residence time of the reaction medium in the extruder is between 8 and 10 minutes for a flow rate of 4.52 kg/h (TDI 0.22 kg/h; PEG 3.90 kg/h; ethoxylated cardanol 0.40 kg/h).

[0191] The product obtained at the extruder outlet is in the form of a molten resin. It is formulated directly at the outlet of the die in a water/cosolvent mixture (Surfaline Ox1008 from Arkema) such that the final formulation contains 30% by weight of polyurethane base, 20% by weight of cosolvent and 50% by weight of water. A portion of the unformulated resin is preserved in order to measure the MVR (melt volume rate).

MVR(100° C./2.16 kg)=13 cm.sup.3/10 min.

Test 5

[0192] This example illustrates the production of an HEUR by addition of polyethylene glycol, of ethoxylated cardanol with H12MDI in the presence of a catalyst.

[0193] The polyethylene glycol used comprises approximately 230 repeating units, the length of the ethoxylate chain of the cardanol is approximately 4 units of ethylene oxide and the catalyst used is dibutyltin dilaurate.

[0194] The PEG/ethoxylated cardanol/DBTDL mixture is placed in a sealed tank heated to 90° C. under vacuum and dehydrated until a water content of less than 800 ppm is obtained. This tank is then inerted with nitrogen.

[0195] The H12MDI is placed in a sealed tank heated to 60° C. and inerted with nitrogen. In this example, area 1 is heated to 25° C. The other 15 areas are heated to 120° C.

[0196] The residence time of the reaction medium in the extruder is between 11 and 14 minutes for a flow rate of 2.31 kg/h (H12MDI 0.16 kg/h; PEG 1.95 kg/h; ethoxylated cardanol 0.20 kg/h).

[0197] The product obtained at the extruder outlet is in the form of a molten resin. It is formulated directly at the outlet of the die in a water/cosolvent mixture (Surfaline Ox1008 from Arkema) such that the final formulation contains 30% by weight of polyurethane base, 20% by weight of cosolvent and 50% by weight of water. A portion of the unformulated resin is preserved in order to measure the MVR (melt volume rate).

MVR(100° C./2.16 kg)=19 cm.sup.3/10 min.

Test 6

[0198] This example illustrates the production of an HEUR by addition of polyethylene glycol, of ethoxylated cardanol with HDI in the presence of a catalyst.

[0199] The polyethylene glycol used comprises approximately 230 repeating units, the length of the ethoxylate chain of the cardanol is approximately 4 units of ethylene oxide and the catalyst used is dibutyltin dilaurate.

[0200] The PEG/ethoxylated cardanol/DBTDL mixture is placed in a sealed tank heated to 90° C. under vacuum and dehydrated until a water content of less than 800 ppm is obtained. This tank is then inerted with nitrogen.

[0201] The HDI is placed in a sealed tank heated to 60° C. and inerted with nitrogen.

[0202] In this example, area 1 is heated to 25° C. The other 15 areas are heated to 120° C. The residence time of the reaction medium in the extruder is between 11 and 14 minutes for a flow rate of 2.25 kg/h (HDI 0.10 kg/h; PEG 1.95 kg/h; ethoxylated cardanol 0.20 kg/h).

[0203] The product obtained at the extruder outlet is in the form of a molten resin. It is formulated directly at the outlet of the die in a water/cosolvent mixture (Surfaline Ox1008 from Arkema) such that the final formulation contains 30% by weight of polyurethane base, 20% by weight of cosolvent and 50% by weight of water. A portion of the unformulated resin is preserved in order to measure the MVR (melt volume rate).

MVR(100° C./2.16 kg)=29 cm.sup.3/10 min.

Test 7

[0204] This example illustrates the production of an HEUR by addition of polyethylene glycol, of ethoxylated cardanol with HDI in the presence of a catalyst.

[0205] The polyethylene glycol used comprises approximately 230 repeating units, the length of the ethoxylate chain of the cardanol is approximately 4 units of ethylene oxide and the catalyst used is dibutyltin dilaurate.

[0206] The PEG/ethoxylated cardanol/DBTDL mixture is placed in a sealed tank heated to 90° C. under vacuum and dehydrated until a water content of less than 800 ppm is obtained. This tank is then inerted with nitrogen.

[0207] The HDI is placed in a sealed tank heated to 60° C. and inerted with nitrogen.

[0208] In this example, area 1 is heated to 25° C. The other 15 areas are heated to 130° C. The residence time of the reaction medium in the extruder is between 11 and 14 minutes for a flow rate of 2.25 kg/h (HDI 0.10 kg/h; PEG 1.95 kg/h; ethoxylated cardanol 0.20 kg/h).

[0209] The product obtained at the extruder outlet is in the form of a molten resin. It is formulated directly at the outlet of the die in a water/cosolvent mixture (Surfaline Ox1008 from Arkema) such that the final formulation contains 30% by weight of polyurethane base, 20% by weight of cosolvent and 50% by weight of water. A portion of the unformulated resin is preserved in order to measure the MVR (melt volume rate).

MVR(100° C./2.16 kg)=12 cm.sup.3/10 min.

Test 8

[0210] This example illustrates the production of an HEUR by addition of polyethylene glycol, of ethoxylated cardanol with HDI in the presence of a catalyst.

[0211] The polyethylene glycol used comprises approximately 230 repeating units, the length of the ethoxylate chain of the cardanol is approximately 4 units of ethylene oxide and the catalyst used is dibutyltin dilaurate.

[0212] The PEG/ethoxylated cardanol/DBTDL mixture is placed in a sealed tank heated to 90° C. under vacuum and dehydrated until a water content of less than 800 ppm is obtained. This tank is then inerted with nitrogen.

[0213] The HDI is placed in a sealed tank heated to 60° C. and inerted with nitrogen.

[0214] In this example, area 1 is heated to 25° C. Areas 2, 3, 4 are heated to 170° C.; the other areas are heated to 120° C.

[0215] The residence time of the reaction medium in the extruder is between 11 and 14 minutes for a flow rate of 2.25 kg/h (HDI 0.10 kg/h; PEG 1.95 kg/h; ethoxylated cardanol 0.20 kg/h).

[0216] The product obtained at the extruder outlet is in the form of a molten resin. It is formulated directly at the outlet of the die in a water/cosolvent mixture (Surfaline Ox1008 from Arkema) such that the final formulation contains 30% by weight of polyurethane base, 20% by weight of cosolvent and 50% by weight of water. A portion of the unformulated resin is preserved in order to measure the MVR (melt volume rate).

MVR(100° C./2.16 kg)=9.2 cm.sup.3/10 min.

Test 9

[0217] This example illustrates the production of an HEUR by addition of polyethylene glycol, of ethoxylated cardanol with HDI in the presence of a catalyst.

[0218] The polyethylene glycol used comprises approximately 230 repeating units, the length of the ethoxylate chain of the cardanol is approximately 4 units of ethylene oxide and the catalyst used is dibutyltin dilaurate.

[0219] The PEG/ethoxylated cardanol/DBTDL mixture is placed in a sealed tank heated to 90° C. under vacuum and dehydrated until a water content of less than 800 ppm is obtained. This tank is then inerted with nitrogen.

[0220] The HDI is placed in a sealed tank heated to 60° C. and inerted with nitrogen.

[0221] In this example, area 1 is heated to 25° C. Areas 2, 3, 4, 5, 6 are heated to 170° C.; the other areas are heated to 120° C.

[0222] The residence time of the reaction medium in the extruder is between 11 and 14 minutes for a flow rate of 2.25 kg/h (HDI 0.10 kg/h; PEG 1.95 kg/h; ethoxylated cardanol 0.20 kg/h).

[0223] The product obtained at the extruder outlet is in the form of a molten resin. It is formulated directly at the outlet of the die in a water/cosolvent mixture (Surfaline Ox1008 from Arkema) such that the final formulation contains 30% by weight of polyurethane base, 20% by weight of cosolvent and 50% by weight of water. A portion of the unformulated resin is preserved in order to measure the MVR (melt volume rate).

MVR(100° C./2.16 kg)=<5 cm.sup.3/10 min.

Test 10

[0224] This example illustrates the production of an HEUR by addition of polyethylene glycol, of ethoxylated tristyryl phenol (TSP) with IPDI in the presence of a catalyst.

[0225] The polyethylene glycol used comprises approximately 230 repeating units, the length of the ethoxylate chain of the TSP is approximately 3 units of ethylene oxide and the catalyst used is dibutyltin dilaurate.

[0226] The PEG/ethoxylated TSP/DBTDL mixture is placed in a sealed tank heated to 90° C. under vacuum and dehydrated until a water content of less than 800 ppm is obtained. This tank is then inerted with nitrogen.

[0227] The IPDI is placed in a sealed tank heated to 60° C. and inerted with nitrogen. In this example, area 1 is heated to 25° C. Areas 2, 3, 4, 5, 6 are heated to 170° C.; the other areas are heated to 120° C.

[0228] The residence time of the reaction medium in the extruder is between 11 and 14 minutes for a flow rate of 2.25 kg/h (IPDI 0.10 kg/h; PEG 1.95 kg/h; ethoxylated TSP 0.20 kg/h).

[0229] The product obtained at the extruder outlet is in the form of a molten resin. It is formulated directly at the outlet of the die in a water/cosolvent mixture (straight C8 ethoxylated alcohol 80E—Surfaline CC8 from Arkema) such that the final formulation contains 30% by weight of polyurethane base, 20% by weight of cosolvent and 50% by weight of water. A portion of the unformulated resin is preserved in order to measure the MVR (melt volume rate).

MVR(100° C./2.16 kg)=14 cm.sup.3/10 min.

Test 11

[0230] This example illustrates the production of an HEUR by addition of polyethylene glycol, of hexan-1-ol with H12MDI in the presence of a catalyst.

[0231] The polyethylene glycol used comprises approximately 230 repeating units and the catalyst used is dibutyltin dilaurate.

[0232] The PEG is placed in a sealed tank heated to 90° C. under vacuum and dehydrated until a water content of less than 800 ppm is obtained. The hexan-1-ol and DBTDL are added, then this tank is inerted with nitrogen.

[0233] The H12MDI is placed in a sealed tank heated to 60° C. and inerted with nitrogen. In this example, area 1 is heated to 25° C. The other areas are heated to 120° C.

[0234] The residence time of the reaction medium in the extruder is between 5 and 7 minutes for a flow rate of 4.31 kg/h (H12MDI 0.32 kg/h; PEG 3.9 kg/h; hexan-1-ol 0.09 kg/h). The product obtained at the extruder outlet is in the form of a molten resin. It is formulated directly at the outlet of the die in water such that the final formulation contains 20% by weight of polyurethane base and 80% by weight of water. A portion of the unformulated resin is preserved in order to measure the MVR (melt volume rate).

MVR(100° C./2.16 kg)=51 cm.sup.3/10 min.

Test 12

[0235] This example illustrates the production of an HEUR by addition of polyethylene glycol, of hexan-1-ol with methylene bis(4-cyclohexylisocyanate) (H12MDI) in the presence of a catalyst.

[0236] The polyethylene glycol used comprises approximately 230 repeating units and the catalyst used is 1,8-diazabicyclo (5, 4, 0) undec-7-ene (DBU).

[0237] The PEG is placed in a sealed tank heated to 90° C. under vacuum and dehydrated until a water content of less than 800 ppm is obtained. The hexan-1-ol and DBU are added, then this tank is inerted with nitrogen.

[0238] The H12MDI is placed in a sealed tank heated to 60° C. and inerted with nitrogen. In this example, area 1 is heated to 25° C. Areas 2, 3, 4 are heated to 170° C.; the other areas are heated to 120° C.

[0239] The residence time of the reaction medium in the extruder is between 11 and 14 minutes for a flow rate of 2.16 kg/h (H12MDI 0.16 kg/h; PEG 1.95 kg/h; hexan-1-ol 0.5 kg/h). The product obtained at the extruder outlet is in the form of a molten resin. It is formulated directly at the outlet of the die in water such that the final formulation contains 20% by weight of polyurethane base and 80% by weight of water. A portion of the unformulated resin is preserved in order to measure the MVR (melt volume rate).

MVR(100° C./2.16 kg)=16 cm.sup.3/10 min.

Tests 13-a and 13-b

[0240] This example illustrates the production of an HEUR by addition of polyethylene glycol, of hexan-1-ol with H12MDI in the presence of a catalyst.

[0241] The polyethylene glycol used comprises approximately 230 repeating units, the length of the ethoxylate chain of the cardanol is approximately 4 units of ethylene oxide and the catalyst used is 1.8-diazabicyclo (5, 4, 0) undec-7-ene (DBU).

[0242] The PEG is placed in a sealed tank heated to 90° C. under vacuum and dehydrated until a water content of less than 800 ppm is obtained. The hexan-1-ol and DBU are added, then this tank is inerted with nitrogen.

[0243] The H12MDI is placed in a sealed tank heated to 60° C. and inerted with nitrogen.

[0244] In this example, area 1 is heated to 25° C. Areas 2, 3, 4 are heated to 170° C.; the other areas are heated to 120° C.

[0245] The residence time of the reaction medium in the extruder is between 11 and 14 minutes for a flow rate of 2.16 kg/h (H12MDI 0.16 kg/h; PEG 1.95 kg/h; hexan-1-ol 0.05 kg/h). The product obtained at the extruder outlet is in the form of a molten resin. It is formulated directly at the outlet of the die in water such that the final formulation contains 20% by weight of polyurethane base and 80% by weight of water. A portion of the unformulated resin is preserved in order to measure the MVR (melt volume rate).

MVR(100° C./2.16 k g)=18 cm.sup.3/10 min  (13-a).

[0246] The pump flow rates are then changed to increase the overall flow rate to 4.31 kg/h (H12MDI 0.32 kg/h; PEG 3.9 kg/h; hexan-1-ol 0.09 kg/h). After balancing for 15 minutes, the residence time is measured by adding a coloured tracer at about 5 to 7 minutes.

MVR(100° C./2.16 kg)=24 cm.sup.3/10 min  (13-b).

Test 14 (Comparison)

[0247] This test corresponds to a polyurethane resulting from the condensation, expressed in % by weight, of each of the constituents: [0248] 85.2% of polyethylene glycol with 230 repeating units of ethylene oxide, [0249] 8.9% of oxyethylated cardanol with 4 units of ethylene oxide, [0250] 5.9% of isophorone diisocyanate.

[0251] 260 g of PEG with 230 repeating units of ethylene oxide and 27 g oxyethylated cardanol with 4 units of ethylene oxide are introduced into a 1 L glass reactor equipped with anchor-type mechanical stirring and a rotary pump to generate vacuum. This mixture is heated to 80° C. using a heating mantle. The reactor is placed under vacuum to dry the mixture. When the water content, measured with a Karl-Fischer type instrument, is less than 800 ppm, 200 ppm of DBTDL and then 18 g of IPDI are introduced. The addition reaction is allowed to continue for 1 hour.

[0252] A portion of the polyurethane obtained is formulated in water in the presence of a surfactant sold as “Surfaline Ox1008” by Arkema (weight ratio: 30% PU, 20% Surfaline Ox1008, 50% water). A sufficient amount is extracted prior to formulation in order to be able to measure the MVR.

MVR(100° C./2.16 kg)=66 cm.sup.3/10 min.

Test 15 (Comparison)

[0253] This test corresponds to a polyurethane resulting from the condensation, expressed in % by weight, of each of the constituents: [0254] 90.5% of polyethylene glycol with 230 repeating units of ethylene oxide, [0255] 8.9% of hexan-1-ol, [0256] 7.4% of H12MDI.

[0257] 195 g of PEG with 230 repeating units of ethylene oxide is introduced into a 1 L glass reactor equipped with anchor-type mechanical stirring and a rotary pump to generate vacuum. The PEG is heated to 80° C. using a heating mantle. The reactor is placed under vacuum to dry it. When the water content, measured with a Karl-Fischer type instrument, is less than 800 ppm, 4.5 g of hexan-1-ol, 200 ppm of DBTDL, then 16 g of H12MDI are introduced, in that order. The addition reaction is allowed to continue for 1 hour.

[0258] A portion of the polyurethane obtained is formulated in water (weight ratio: 20% PU, 80% water). A sufficient amount is extracted prior to formulation in order to be able to measure the MVR.

MVR(100° C./2.16 kg)=72 cm.sup.3/10 min.

EXAMPLE 2

[0259] This example illustrates the use of polyurethanes according to the invention and comparative polyurethanes as thickening agents in a solvent-free matte paint.

[0260] The paint composition is detailed in Table 1, with the weights of each constituent indicated in grams. The thickeners all have a solids content of 30% by weight of active ingredient. The paint is formulated according to known methods.

TABLE-US-00001 TABLE 1 Ingredients in the Water-based Paint Formulation Quantity (g) Ecodis P50 (COATEX dispersant) 2.0 Tego 1488 (TEGO Antifoam) 0.76 Mergal K6N (TROY bactericide) 1.0 TiONa RL68 (MILLENIUM TiO.sub.2) 40.98 Omyacoat 850 OG (OMYA CaCO.sub.3) 66.51 Durcal 5 (OMYA CaCO.sub.3) 150.02 Mowilith LDM 1871 (CLARIANT binder) 75.78 NaOH 0.82 Thickening polyurethane composition 6.18 Water 155.95 Total 500.00

[0261] The resulting viscosities are then determined at different shear rates: [0262] at low shear rate: Brookfield™ viscosity of 10 and 100 rpm, respectively denoted BV10 and BV100 (mPa.$), [0263] at moderate shear rate: Stormer viscosity (Krens Unit, KU), [0264] at high shear rate: ICI viscosity (0.1 Pa.$).

[0265] These measurements are done 24 hours after the formulation has been prepared. The formulations are temperature-controlled at 25±0.5° C.

[0266] It should be recalled that, in the field of water-based paints, high viscosity at high shear rates reflects good dynamic behaviour. In practice, the viscosity of the paint remains sufficiently high during the step of applying the paint onto the substrate. The advantages can be greater build (i.e. a thicker coat weight) and less tendency to splatter.

[0267] At the same time, high viscosity at low or moderate shear rates reflects good static behaviour. Thus, good stability is ensured during storage while avoiding the settling phenomenon and limiting the tendency to flow on vertical substrates. Examples A1 to A14 were carried out using the thickener produced during the corresponding tests 1 to 14 in Example 1.

TABLE-US-00002 TABLE 2 Matte Paint Formulation Brookfield Brookfield Stormer Viscosity 10 Viscosity 100 Viscosity ICI Viscosity Example mPa .Math. s mPa .Math. s KU 0.1 Pa .Math. s A1 18,050 4,410 116 0.7 A2 17,200 4,220 114 0.65 A3 21,500 5,350 121 0.8 A4 28,600 7,880 137 0.8 A5 22,900 5,860 126 0.7 A6 21,100 5,400 122 0.65 A7 28,900 7,810 139 0.75 A8 29,700 8,020 >141 0.85 A9 30,850 8,100 >141 0.8  A14 17,500 4,320 116 0.7

[0268] These results demonstrate that the polyurethane compositions according to the invention make it possible to effectively thicken a solvent-free matte paint, regardless of the shear rate. In addition, the polyurethanes according to tests A4, A5, A7, A8, A9 offer performances that are higher than those of the reference A14.

[0269] The viscosities obtained at high shear gradients are preserved, the viscosities measured at moderate and low shear rates are substantially improved. The efficacy of these polyurethanes as pseudoplastic additives is greater.

EXAMPLE 3

[0270] This example illustrates the use of polyurethanes according to the invention and comparative polyurethanes as thickening agents in a thickening latex formula.

[0271] The composition of the formulation is detailed in Table 3, with the weights of each constituent indicated in grams.

[0272] The thickeners all have a solids content of 20% by weight of active ingredient. Formulation is carried out according to the methods known to the person skilled in the art.

TABLE-US-00003 TABLE 3 Binder Formulation Ingredients Quantity (g) Encor 662 (Arkema Coating Resins) 161.0 28% ammonia in water Qsp pH = 8.5 Polyurethane tested as is 24 Water 45

[0273] The resulting viscosities are then determined at different shear rates: [0274] at low shear rate: Brookfield™ viscosity at 10 rpm, respectively denoted VB10 (in mPa.Math.s), [0275] at moderate shear rate: Stormer viscosity (Krens Unit, KU), [0276] at high shear rate: TCT viscosity (0.1 Pa.Math.s).

[0277] These measurements are done 1 hour after the formulation has been prepared. The formulations are temperature-controlled at 25±0.5° C.

TABLE-US-00004 TABLE 4 Thickening Latex Formulation Brookfield Viscosity 10 Stormer Viscosity ICI Viscosity Example mPa .Math. s KU 0.1 Pa .Math. s A11   730 77 1.8 A12   3,350 105 3.1 A13-a 2,400 96 2.8 A13-b 1,470 91 2.6 A15   680 74 1.6

[0278] These results demonstrate that the polyurethanes according to the invention effectively thicken a water/latex mixture neutralised to pH=8.5, regardless of the shear rate. In addition, the polyurethanes according to tests A11, A12, A13-a, A13-B offer performances that are higher than those of the reference A15.

[0279] The viscosities obtained at high and low shear gradients are significantly higher; the viscosities measured at moderate shear rate are substantially improved. The effectiveness of these polyurethanes as Newtonian additives is better.