Soil Release Polyesters For Use In Detergent Compositions

Abstract

The invention relates to a polyester comprising two or more of the structural units (a1), one or more of the structural units (a2) and either one or two of the terminal groups (a3)

##STR00001##

wherein G.sup.1 is one or more of (OC.sub.nH.sub.2n) with n being a number of from 2 to 10, preferably from 2 to 6 and more preferably (OC.sub.2H.sub.4), (OC.sub.3H.sub.6), (OC.sub.4H.sub.8) or (OC.sub.6H.sub.12), R.sup.1 is a C.sub.1-30 alkyl, preferably C.sub.1-4 alkyl and more preferably methyl, p is, based on a molar average, a number of at least 60, preferably from 70 to 200 and more preferably from 90 to 130, q is, based on a molar average, a number of from 0 to 40, preferably from 0 to 30, more preferably from 0 to 20, and most preferably from 0 to 10,

where

the (OC.sub.3H.sub.6)— and (OC.sub.2H.sub.4)-groups of the terminal group (a3) may be arranged blockwise, alternating, periodically and/or statistically, preferably blockwise and/or

statistically,

either of the groups (O—C.sub.3H.sub.6)— and (O—C.sub.2—H.sub.4)— of the terminal group (a3) can be linked to R.sup.1— and O—,

adjacent structural units (a1) are connected by the structural unit (a2), in the case that only one terminal group (a3) is present in the polyester, the other terminal group is selected from the group consisting of OH, OCH.sub.3, and G.sup.1OH, and both terminal groups are linked to acyl groups derived from a dicarboxylic acid, preferably to structural units (a1).

Claims

1. A polyester comprising two or more of the structural units (a1), one or more of the structural units (a2) and either one or two of the terminal groups (a3) ##STR00014## wherein G.sup.1 is one or more of (OC.sub.nH.sub.2n) with n being a number of from 2 to 10, R.sup.1 is a C.sub.1-30 alkyl, p is, based on a molar average, a number of at least 60, q is, based on a molar average, a number of from 0 to 40, where the (OC.sub.3H.sub.6)— and (OC.sub.2H.sub.4)-groups of the terminal group (a3) may be arranged blockwise, alternating, periodically and/or statistically, either of the groups (O—C.sub.3H.sub.6)— and (O—C.sub.2—H.sub.4)— of the terminal group (a3) can be linked to R.sup.1— and O—, adjacent structural units (a1) are connected by the structural unit (a2), in the case that only one terminal group (a3) is present in the polyester, the other terminal group is selected from the group consisting of OH, OCH.sub.3, and G.sup.1OH, and both terminal groups are linked to acyl groups derived from a dicarboxylic acid.

2. The polyester according to claim 1, wherein q is 0

3. The polyester according to claim 1, wherein R.sup.1 is methyl.

4. The polyester according to claim 1, wherein G.sup.1 is (OC.sub.2H.sub.4) and/or (OC.sub.3H.sub.6).

5. The polyester according to claim 1, wherein the terminal groups (a3), based on the total weight of the polyester, comprise at least 50 wt. %.

6. The polyester according to claim 1, wherein the weight average molecular weight (M.sub.w) is from 6000 to 20000 g/mol.

7. The polyester according to claim 1, wherein the average number of structural units (a1) is from 2 to 60.

8. The polyester according to claim 1, wherein the total amount of structural units (a1) and (a2) and of the terminal group (a3), based on the total weight of the polyester, is at least 50 wt. %.

9. The polyester according to claim 1, wherein the polyester has a melting point of at least 50 C.

10. The polyester according to claim 1, wherein the polyester has a flow factor, of at least 10.

11. The polyester according to claim 1, wherein the polyester consists of structural units selected from the group consisting of structural units (a1) and (a2) and the respective terminal groups.

12. The polyester according to claim 1, comprising one or more structural units (a1′),
—C(═O)-A-C(═O)—  (a1′) where A is derived from a dicarboxylic acid different from terephthalic acid.

13. A process for the preparation of a polyester comprising two or more of the structural units (a1), one or more of the structural units (a2) and either one or two of the terminal groups (a3) ##STR00015## wherein G.sup.1 is one or more of (OC.sub.nH.sub.2n) with n being a number of from 2 to 10, R.sup.1 is a C.sub.1-30 alkyl, p is, based on a molar average, a number of at least 60 q is, based on a molar average, a number of from 0 to 40, where the (OC.sub.3H.sub.6)— and (OC.sub.2H.sub.4)-groups of the terminal group (a3) may be arranged blockwise, alternating, periodically and/or statistically, either of the groups (O—C.sub.3H.sub.6)— and (O—C.sub.2—H.sub.4)-— of the terminal group (a3) can be linked to R.sup.1— and O—, adjacent structural units (a1) are connected by the structural unit (a2), in the case that only one terminal group (a3) is present in the polyester, the other terminal group is selected from the group consisting of OH, OCH.sub.3, and G.sup.1OH, and both terminal groups are linked to acyl groups derived from a dicarboxylic acid, comprising the steps of heating dimethyl terephthalate, optionally one or more dimethyl esters of dicarboxylic acids, one or more glycols H—G.sup.1-OH, and one or more alkyl capped polyalkylene glycols ##STR00016## where the symbols and indices are as defined aboved with the addition of a catalyst, to temperatures of 160 to 220° C., and then continuing the reaction under reduced pressure at temperatures of from 160 to 240° C.

14. (canceled)

15. (canceled)

16. A solid or liquid detergent composition, comprising a) one or more polyesters according to claim 1 and b) one or more surfactants.

17. The composition according to claim 16, wherein the one or more polyesters a) are present in an amount of at least 0.1 wt.-%, based on the total weight of the detergent composition.

18. The composition according to claim 16, wherein the one or more surfactants b) are present in an amount of at least 3 wt.-%, based on the total weight of the detergent composition.

19. The composition according to claim 16, wherein the detergent composition is a liquid.

20. The composition according to claim 16, wherein the detergent composition is a solid.

21. A method for enhancing soil removal during laundering by modifying the surface of a fabric that is being laundered comprising the step of contacting the fabric with a polyester comprising two or more of the structural units (a1), one or more of the structural units (a2) and either one or two of the terminal groups (a3) ##STR00017## wherein G.sup.1 is one or more of (OC.sub.nH.sub.2n) with n being a number of from 2 to 10, R.sup.1 is a C.sub.1-30 alkyl, p is, based on a molar average, a number of at least 60 q is, based on a molar average, a number of from 0 to 40, where the (OC.sub.3H.sub.6)— and (OC.sub.2H.sub.4)-groups of the terminal group (a3) may be arranged blockwise, alternating, periodically and/or statistically, either of the groups (O—C.sub.3H.sub.6)— and (O—C.sub.2—H.sub.4)— of the terminal group (a3) can be linked to R.sup.1— and O—, adjacent structural units (a1) are connected by the structural unit (a2), in the case that only one terminal group (a3) is present in the polyester, the other terminal group is selected from the group consisting of OH, OCH.sub.3, and G.sup.1OH, and both terminal groups are linked to acyl groups derived from a dicarboxylic acid.

Description

EXAMPLES

[0151] The examples below are intended to illustrate the invention in detail without, however, limiting it thereto. Unless explicitly stated otherwise, all percentages given are percentages by weight (% by wt. or wt.-%).

[0152] Polymer Preparation

[0153] General Procedure for the Preparation of the Polyesters of the Examples

[0154] The polyester synthesis is carried out by the reaction of dimethyl terephthalate (DMT), one or more alkylene glycols, and one or more alkyl capped polyalkylene glycols, using sodium acetate (NaOAc) and tetraisopropyl orthotitanate (IPT) as the catalyst system. The synthesis is a two-step procedure. The first step is a transesterification and the second step is a polycondensation.

[0155] Transesterification

[0156] The reactants are weighed into a reaction vessel at room temperature under a nitrogen atmosphere. The mixture is heated to an internal temperature of 65° C. for melting and homogenization, followed by the addition of 200 μl tetraisopropyl orthotitanate.

[0157] Within 2 hours, the temperature of the reaction mixture is continuously increased to 210° C. under a weak nitrogen flow and held at this temperature for 2 hours. During the transesterification methanol is released from the reaction and is distilled out of the system. After 2 h at 210° C. nitrogen is switched off and the pressure is reduced to 400 mbar over 3 h.

[0158] Polycondensation

[0159] The mixture is heated up to 230° C. At 230° C. the pressure is reduced to 1 mbar over 160 min. Once the polycondensation reaction has started, the alkylene glycol or mixture of alkylene glycols is distilled out of the system. The mixture is stirred for 4 h at 230° C. and a pressure of 1 mbar. After the end of this time period, the inner pressure of the reaction vessel is set back to 1 bar using N.sub.2 and the polymer melt is subsequently removed from the reactor and allowed to solidify.

[0160] Key to Reactants Ued in the Examples [0161] mPEG1000 is mono hydroxyl-functional polyethylene glycol monomethyl ether, average molecular weight 1 kDa (Polyglykol M 1000, Clariant). [0162] mPEG2000 is mono hydroxyl-functional polyethylene glycol monomethyl ether, average molecular weight 2 kDa (Polyglykol M 2000, Clariant). [0163] mPEG3000 is mono hydroxyl-functional polyethylene glycol monomethyl ether, average molecular weight 3 kDa (Polyglykol M 3000, Clariant). [0164] mPEG4000 is mono hydroxyl-functional polyethylene glycol monomethyl ether, average molecular weight 4 kDa (Polyglykol M 4000, Clariant). [0165] mPEG5000 is mono hydroxyl-functional polyethylene glycol monomethyl ether, average molecular weight 5 kDa (Polyglykol M 5000, Clariant). [0166] PG is propylene glycol [0167] DMT is dimethyl terephthalate [0168] IPT is tetraisopropyl orthotitanate [0169] NaOAc is sodium acetate

TABLE-US-00001 TABLE I Polyester examples I to V and Comparative example I to II Polyester Comparative Comparative Example I Example II Example III Example IV Example V Example I Example II Reactant Weight [g] Weight [g] Weight [g] Weight [g] Weight [g] Weight [g] Weight [g] DMT 100 100 100 17.62 12.53 100 100 PG 79.9 79.9 79.9 11.05 7.85 79.9 79.9 NaOAc 0.5 0.5 0.5 0.1 0.1 0.5 0.5 IPT 0.2 0.2 0.2 0.04 0.04 0.2 0.2 mPEG1000 325 mPEG2000 325 mPEG3000 325 mPEG4000 325 mPEG5000 325 75 75 Yield 426.3 427.6 426.7 93.4 88.0 421.1 424.5

Comparative Example III

[0170] This polyester was prepared as described in DE 10 2007 013 217 (A1) Polyester 9 on page 25.

Comparative Example IV

[0171] This polyester was prepared as described in EP 2 276 824 (B1) Polyester 1 in Table 1 on page 20.

TABLE-US-00002 TABLE II Properties of Polyester Examples I to V and Comparative examples I to IV Melting Appearance of temperature Flow factor 30 wt.-% GPC Mw [° C.] (ffc) solution Example I 8778 55.7 10 Clear solution Example II 11270 57.9 10 Clear solution Example III 9998 58.9 11 Clear solution Example IV 9028 61.1 — — Example V 9338 63.3 — — Comparative 4374 36 — Clear solution example I Comparative 7338 52.5  9 Turbid solution example II Comparative — — 40 sediment example III Comparative — — — sediment example IV

[0172] Solution stability of the resulting polyesters was assessed by preparing a mixture of the prepared polyester (30 wt.-%) in water (20 wt.-%) and propylene glycol (50 wt.-%). The resulting mixtures were evaluated visually after two days of storage.

[0173] A series of exemplary liquid laundry detergent compositions, both according to the invention (with a polyester of the invention) and not according to the invention (without a polyester of the invention), were prepared according to Table III.

[0174] Key to Ingredients Used in the Compositions of Table III and Table VI [0175] LAS is C.sub.12-14 linear alkylbenzene sulfonate, sodium salt [0176] SLES 2EO is sodium lauryl ether sulfate with 2 moles EO (Genapol® LRO, Clariant). [0177] NI 7EO is C.sub.12-15 alcohol ethoxylate 7EO nonionic (Genapol® LA070, Clariant) [0178] Fatty Acid is a C.sub.12-18 stripped palm kernel fatty acid [0179] SRP is a polyester prepared according to examples from Tables I and II

TABLE-US-00003 TABLE III Liquid laundry detergent compositions for performance testing wt.-% a.m. Ingredient 1 2 LAS 5.20 5.20 SLES 2EO 6.50 6.50 NI 7EO 5.20 5.20 Fatty Acid 2.80 2.80 Glycerol 2.40 2.40 Ethanol 1.20 1.20 Sodium citrate 1.70 1.70 Sodium tetraborate decahydrate 2.00 2.00 SRP 0.00 1.00 Demin water and NaOH to adjust pH ad 100 ad 100 pH Value 8.4  8.4  Appearance at room temperature clear clear

[0180] Soil Release Test

[0181] Liquid laundry detergent compositions of the invention were prepared according to the compositions listed in Table III. Powder detergent compositions were prepared from an IEC-A* base formulation by adding 1wt.-% of polyester of the invention on top of the base formulation (IEC-A* base from WFK Testgewebe GmbH). The detergent formulations were tested for their soil release performance according to the “Dirty-Motor Oil” Test (DMO-Test) using a Lini Apparatus. The conditions for the test are listed in Table IV.

TABLE-US-00004 TABLE IV Washing conditions - Soil Release Test Equipment Linitest Plus (SDL Atlas) Water hardness 14° dH Washing temperature 40° C. Washing time 30 min Detergent concentration 4.3 g/l liquid detergent 3 g/l powder detergent Soiled Fabric:Liquor Ratio 1:40

[0182] As test fabric, white polyester standard swatches (WFK 30A from WFK Testgewebe GmbH) were used. The fabrics were prewashed three times with the laundry detergent compositions. The swatches were then rinsed, dried and soiled with 25 μl of dirty motor oil. After 1 hour the soiled fabrics were washed again with the same stored laundry detergent compositions used in the pre-washing step.

[0183] After rinsing and drying the washed swatches, a measurement of the remission of the stained fabric at 457 nm was made using a spectrophotometer (Datacolor 650).

[0184] The soil release performance is shown as an improvement in soil removal of the swatches washed with a formulation containing the polyesters of the invention (Soil Release Polymer, SRP) compared with the same formulation containing no SRP:

ΔR=R.sub.with SRP−R.sub.without SRP

[0185] The washing results obtained for the laundry detergent compositions comprising the soil release polymers of the invention are shown in Table V and Table VI, expressed as ΔR along with the 95% confidence intervals.

TABLE-US-00005 TABLE V Washing results liquid detergents Example No. ΔR 95% CI I 19.6 1.3 III 16.8 2.2 Comparative I 17.2 0.8 Comparative III 13.3 1.9 Comparative IV 12.4 1.1

TABLE-US-00006 TABLE VI Washing results powder detergents Example No. ΔR 95% CI I 8.2 1.6 III 8.4 1.6 Comparative I 6.7 1.5 Comparative III 8.2 0.9 Comparative IV 5.8 2.0

[0186] Water Uptake Test

[0187] Polyester samples were stored at room temperature and 80% RH. The weight increase of the polyester samples was monitored over time and is shown in Table VII.

TABLE-US-00007 TABLE VII Water uptake results for polyester powders Polyester Example III Comparative III Time Water uptake Water uptake [min] [wt.-%] [wt.-%] 0 0.0 0.0 30 0.4 0.9 60 0.2 3.5 120 −0.4 3.5 180 −0.6 3.3