Biodegradable multiblock copolymer surfactants

Abstract

Surfactant compositions include one or more multiblock copolymer surfactants having a general formula of: R-O-[AO]x[AOa EOb]y[EO]c, where R is a linear or branched, saturated or unsaturated C6 to C18 carbon chain; AO is a C3 to C6 alkylene oxide and x ranges from 0 to 5; y is at least 1, [AOa EOb] designates a block copolymer where a ranges from 1 to 20, b ranges from 0.5 to 3.5; and c ranges from 1 to 50. Methods include polymerizing, in the presence of an alcohol R-OH, one or more C3 to C6 alkylene oxides to generate a first product; polymerizing, in the presence of the first product, a mixture of one or more alkylene oxides and ethylene oxide to form block [AOa EOb] and generate a second product; and polymerizing, in the presence of the second product, ethylene oxide to generate the multiblock copolymer surfactant.

Description

[0001] BIODEGRADABLE MULTIBLOCK COPOLYMER SURFACTANTS

[0002] Field

[0003] Embodiments relate to multiblock copolymer surfactants, methods of preparation, and methods of use thereof.

[0004] Introduction

[0005] Surfactants are used in the chemical and manufacturing industries for a wide variety of purposes. These include, for example, imparting or enhancing wettability and detergency in products including wetting agents, emulsifiers, rinse aids, defoam / low foam agents, spray cleaning agents, drug delivery agents, emulsifiers for herbicides and pesticides, metal cleaning agents, paints, coatings, agricultural spread and crop growth agents, stabilizing agents for latexes, paints, and paper products, and the like. Large classes of surfactants include nonionic surfactants, which are often indicated as generating less foam than their ionic counterparts. Nonionic surfactants are frequently selected to be biodegradable and have low aquatic toxicity profiles, making them suitable for various applications such as coating, crop applications, and industrial cleaning. However, properties such as high critical micelle concentration (CMC) and suboptimal cleaning performance have hindered widespread adoption of nonionic surfactants across different industries.

[0006] Summary

[0007] In one aspect, embodiments disclosed herein include surfactant compositions having one or more multiblock copolymer surfactants having a general formula of: R-O-[AO]x[AOaEOb]y[EO]c, where R is a linear or branched, saturated or unsaturated C6 to C18 carbon chain; AO is a C3 to C6 alkylene oxide and x ranges from 0 to 5 ; y is at least 1 , [AOaEOb] designates a block copolymer where a ranges from 1 to 20, b ranges from 0.5 to 3.5; and c ranges from 1 to 50.

[0008] In another aspect, methods include polymerizing, in the presence of an alcohol R-OH, one or more C3 to C6 alkylene oxides to generate a first product; polymerizing, in the presence of the first product, a mixture of one or more alkylene oxides and ethylene oxide to form block [AOaEOb] and generate a second product; and polymerizing, in the presence of the second product, ethylene oxide to generate the multiblock copolymer surfactant.

[0009] Detailed Description

[0010] Embodiments relate to multiblock copolymer surfactants, methods of preparation, and methods of use thereof. Multiblock copolymer surfactants disclosed herein may be prepared from the polyaddition of alkylene oxide blocks containing one or more comonomers onto a C6 to C18 alcohol starting compound. Surfactants also include one or more random and / or gradient copolymer blocks that may improve biodegradability, while also reducing CMC and foaming properties. Random and gradient copolymer blocks may tune hydrophilicity and biodegradability by incorporating ethylene oxide (EO) into blocks of one or more alkylene oxide (AO) comonomers at a AO / EO molar equivalent ratio of 2 to 30.

[0011] Polyalkylene oxides are widely used as nonionic surfactants and for producing fatty alcohol-based surfactants, which demonstrate cleaning efficiency and high solubility in water for cleaning hard surfaces, adjuvancy in agrochemical formulations, and low foaming properties. AO comonomers having carbon numbers of 3 or more are often added to a starting alcohol to increase hydrophobicity of the surfactant, which reduces CMC and enhances detergent properties. However, as the content and block size of AO comonomers increases (e.g., PO blocks of >6 molar equivalents) biodegradability begins to decrease, which can fall below international regulatory standards (e.g., OECD requirements for biodegradability and accumulation).

[0012] To overcome these challenges, polyadditions of hydrophilic EO blocks may be incorporated to allow higher PO (and greater carbon number AO) content, breaking up the PO block and improving biodegradability. However, the introduction of EO comonomers and blocks can change modify the hydrophobicity and resulting cleaning efficiency, and it is important for surfactant design to balance surfactant performance and biodegradability.

[0013] Multiblock copolymer surfactants disclosed herein may include an alkyl alcohol modified with multiple blocks of alkylene oxides, including at least one block that incorporates EO by random or gradient polymerization. Multiblock copolymer surfactants disclosed herein provide low CMC, and enhanced biodegradability and surfactant performance in various applications such as laundry, hard surface cleaning, and dishwashing. Surfactant compositions disclosed herein may be prepared from the poly addition of alkylene oxides as copolymer blocks onto a C8 to C18 alcohol starting compound in the presence of a catalyst.

[0014] Alkyl alcohol starting compounds may be linear or branched, primary or secondary C6- C18 alcohols, such as hexanol, octanol, nonanol, decanol, 2-ethylhexanol, 2-propylheptanol, C8- C10 linear alcohol mixtures, tridecanol, isotridcanol, and the like. Polyaddition to the alkyl alcohol may include modification with at least one block of AO that includes C3 to C6 alkylene oxides, such as propylene oxide, butylene oxide, and the like.

[0015] Block copolymers may include mixtures of AO and EO comonomers, where EO is introduced by random or gradient polymerization. Random block polymerization involves cofeeding major comonomers (i.e., AO) and minor comonomers (i.e., EO) at a fixed AO / EO ratio during polymerization. The resulting random block includes the minor comonomer (usually EO) randomly spaced throughout the block. Preparation of the AOEO block may also include the formation of a gradient copolymer in which the concentration of the minor comonomers introduced into the reaction (and into the extending polymer chains) is varied as polymerization progresses. Control over the gradient concentration of the minor comonomer may be effected by any suitable method, including modifying the feed rate of one or more comonomers, introducing comonomers of differing reactivity, or modifying the total time period that the respective comonomer is fed into a polymerization zone (e.g., batch or continuous reactor). For example, generation of a gradient copolymer block [AOEO] may include co-feeding one or more alkylene oxides (e.g., PO) as a primary feed stream and EO as a secondary feed stream to a polymerization zone, wherein the time period for feeding from the secondary EO feed stream is less than the time period for feeding the primary AO stream, resulting in a gradual trailing off of the concentration of free EO in the polymerization. For example, a gradient block polymerization may include a polyaddition in which a concentration of AO is fed for 180 minutes from the start of the reaction, while the secondary (or minor) comonomer EO is fed for 23 minutes from the start. The feed rates (e.g., wt / min) may be the same or different during a gradient polymerization.

[0016] Following the generation of the random and / or gradient [AOEO] block, multiblock surfactant compositions may be capped by additional AO or EO blocks. For example, a multiblock surfactant may be prepared in which a random polymerization of a [EOPO], followed by the EO addition (e.g., 9 mole) to make the target surfactant.

[0017] Multiblock copolymer surfactants may include at least one random or gradient block copolymer containing one or more EO comonomers and one or more AO comonomers. Multiblock copolymer surfactants also include surfactants “capped” with EO. Multiblock copolymer surfactants disclosed herein may have the general formula:

[0018] R-O-[AO]x[AOaEOb]y[EO]cwhere R is a linear or branched, saturated or unsaturated C6 to C18 carbon chain; AO is a C3 to C6 alkylene oxide and x ranges from 0 to 10; y is at least 1, [AOaEOt>] designates a block copolymer where a ranges from 1 to 20, b ranges from 0.3 to 3.5; and c ranges from 1 to 50.

[0019] In some cases, multiblock copolymer surfactants has a general formula of:

[0020] R- O-[POaEOb]y[EO]cwhere R is a linear or branched, saturated or unsaturated C6 to C18 carbon chain; y is at least 1 and designates a block copolymer of PO and EO, a ranges from 1 to 20, b ranges from 0.5 to 3.5, and the ratio a / b ranges from 2 to 30; and c ranges of 1 to 50.

[0021] Multiblock copolymer surfactants may have a number average molecular weight ranging from 30 Da to 4000 Da, or 30 Da to 3000 Da. Multiblock copolymer surfactants disclosed herein may have an average hydroxyl number (OH number) as determined according to ASTM D4274-21 ranging from 20 mg KOH / g to 100 mg KOH / g, 25 mg KOH / g to 90 mg KOH / g, or 25 mg KOH / g to 80 mg KOH / g.

[0022] Multiblock copolymer surfactants disclosed herein may have a CMC of 1000 ppm or less, 500 ppm or less, or 250 ppm or less.

[0023] Multiblock copolymer surfactants disclosed herein may have a cloud point in water of 30 °C or more, 40 °C or more, or 50 °C or more. In some cases, multiblock copolymer surfactants disclosed herein may have a cloud point in the range of 30 °C to 120 °C, 35 °C to 100 °C, or 40 °C to 100 °C.

[0024] Applications for multiblock copolymer surfactants include a wide variety of formulations and products used as cleaners, detergents, hard surface cleaning formulations, polyurethanes, epoxies, thermoplastics, paints, coatings, metal products, agricultural products including herbicides and pesticides, oilfield and mining products, pulp and paper products, textiles, water treatment products, flooring products, inks, colorants, pharmaceuticals, cleaning products, personal care products, lubricants, and combinations thereof. In preparing these and other types of formulations and products, multiblock copolymer surfactants may contribute to or enhance a desirable property, such as surfactancy, detergency, wetting, re-wetting, foam reduction, additive stabilization, latex stabilization, drug delivery capability, emulsification, rinsing, plasticization, reactive dilution, rheology modification, suspension, pseudoplasticization, thickening, curing, impact modification, lubrication, emulsification and micro-emulsification, a combination thereof, or the like.

[0025] Examples of these applications include utility as surfactants in general; as low foam surfactants for household and commercial cleaning; as low foam surfactants in mechanical cleaning processes, as reactive diluents in casting, encapsulation, flooring, potting, adhesives, laminates, reinforced plastics, and filament windings; as coatings; as wetting agents; as rinse aids; as defoam / low foam agents; as spray cleaning agents; as emulsifiers for herbicides and pesticides; as metal cleaning agents; as suspension aids and emulsifiers for paints and coatings; as mixing enhancers in preparing microheterogeneous mixtures of organic compounds in polar and nonpolar carrier fluids for agricultural spread and crop growth agents ; as stabilizing agents for latexes ; as microemulsifiers for pulp and paper products; and the like.

[0026] The surfactant of the present invention is useful as a component in a fully formulated detergent in hard surface cleaning formulations, such as dishwashing detergents for automatic dishwashers. To use the surfactant of the present invention as a dishwasher detergent, place the detergent composition containing the surfactant into an automatic dishwasher. While formulation components and properties have been disclosed individually, it is envisioned that component elements may be included, excluded, or combined in any manner or subcombination utilizing any of the above concentration ranges and nested subranges therein. Further, that the recited formulation properties may be similarly achieved through various combinations of the recited components within the recited ranges.

[0027] The numerical ranges disclosed herein include all values from, and including, the lower and upper value and all values in between. Unless stated to the contrary, implicit from the context, or customary in the art, all parts and percentages are based on weight and all test methods are current as of the filing date of this disclosure.

[0028] Examples

[0029] The following examples are provided to illustrate the embodiments of the invention, but are not intended to limit the scope thereof. Table 1 provides the materials used in the following examples.

[0030] Example 1: Synthesis of multiblock copolymer surfactants

[0031] Inventive Surfactant 1 : A multiblock copolymer surfactant containing a random EOPO bock having the structure of 2EH+[r-1.5EO9PO]+9EO was prepared as follows. A 15 L conical reaction vessel, equipped with magnetically coupled stirrer head and temperature control, was charged with 500.9 g of 2-ethylhexanol and 14.31 g of 45% potassium hydroxide aqueous solution. This solution was stirred at 200rpm and heated up to a temperature of 105°C. Vacuum was applied to keep the solution at 30 mBar in order to remove the water. Residual water was measured, by means of Karl Fischer titration equipment, to be 510 ppm after two hours at the above-mentioned conditions. The solution was cooled to 100°C and nitrogen was introduced in the reactor to release vacuum. The alkoxy lation reaction was carried out in two steps. In the first step, 2008 g of 1,2- propylene oxide and 254 g of ethylene oxide were cofed to the solution in 240min at 135 °C while stirring at 320 rpm. After all the oxides were fed, the reaction was allowed to progress for a period of 8 h at 135 °C to digest all the oxides present. In the second step, 1523 g of ethylene oxide were fed in 390min at constant feed rate at 135 °C. After all the oxide was fed, the reaction was allowed to progress for a period of 4 h at 135 °C to digest all the oxide present. In both steps, pressure in the reaction vessel was closely monitored and oxide feed constraints were in place to not exceed a pressure of 3.5 bar. The solution was then cooled to 80°C and 10.2g of acetic acid 70% solution in water were added. The solution was stirred at rate of 350 rpm for 1 h.

[0032] Inventive Surfactant 2: A multiblock copolymer surfactant containing a random EOPO block having the structure of 2EH+[r-3.0EO9PO]+9EO was prepared as follows. A 15 L conical reaction vessel, equipped with magnetically coupled stirrer head and temperature control, was charged with 215.3 g of 2-ethylhexanol and 6.6 g of 45% potassium hydroxide aqueous solution. This solution was stirred at 200 rpm and heated up to a temperature of 105 °C. Vacuum was applied to keep the solution at 30 mBar in order to remove the water. Residual water was measured, by means of Karl Fischer titration equipment, to be 1060 ppm after two hours at the above-mentioned conditions. The solution was cooled to 100 °C and nitrogen was introduced in the reactor to release vacuum.

[0033] The alkoxy lation reaction was carried out in two steps. In the first step, 863 g of 1,2- propylene oxide and 218 g of ethylene oxide were cofed to the solution in 180 min at 135 °C while stirring at 320 rpm. After all the oxides were fed, the reaction was allowed to progress for a period of 6 h at 135 °C to digest all the oxides present. In the second step, 614.6 g of ethylene oxide were fed in 360 min at constant feed rate at 135 °C. After all the oxide was fed, the reaction was allowed to progress for a period of 4 h at 135 °C to digest all the oxide present. In both steps, pressure in the reaction vessel was closely monitored and oxide feed constraints were in place to not exceed a pressure of 3.5 bar. The solution was then cooled to 80 °C and 4.6 g of 70% acetic acid in water were added. The solution was stirred at rate of 350 rpm for Ih.

[0034] Inventive Surfactant 3: A multiblock copolymer surfactant containing a gradient EOPO block having the structure of 2EH+4PO+[g-1.5EO5PO]-i-9EO was prepared as follows. A 15 L conical reaction vessel, equipped with magnetically coupled stirrer head and temperature control, was charged with 212.7 g of 2-ethylhexanol and 6.1 g of 45% potassium hydroxide aqueous solution. This solution was stirred at 200rpm and heated up to a temperature of 105°C. Vacuum was applied to keep the solution at 30 mBar in order to remove the water. Residual water was measured, by means of Karl Fischer titration equipment, to be 500 ppm after two hours at the above-mentioned conditions. The solution was cooled to 100 °C and nitrogen was introduced in the reactor to release vacuum.

[0035] The alkoxylation reaction was carried out in three steps. In the first step 367.7 g of propylene oxide were fed to the solution in 60 min at 135 °C while stirring at 320 rpm. After all the oxide was fed, the reaction was allowed to progress for a period of 0.5 h at 135 °C to digest some of the oxide present. In the second step, 460 g of 1 ,2-propylene oxide and 105 g of ethylene oxide were cofed to the solution at 135 °C while stirring at 320 rpm. in this step, the two oxides feeds were started at the same time with same feed rates. The ethylene oxide was fed in 25 minutes while the propylene oxide feed was completed in 110 minutes. After all the oxides were fed, the reaction was allowed to progress for a period of 6h at 135°C to digest all the oxides present.

[0036] In the third step, 627.6 g of ethylene oxide were fed in 360min at constant feed rate at 135°C. After all the oxide was fed, the reaction was allowed to progress for a period of 4h at 135°C to digest all the oxide present. In both steps, pressure in the reaction vessel was closely monitored and oxide feed constraints were in place to not exceed a pressure of 3.5 bar. The solution was then cooled to 80°C and 4.3g of acetic acid 70% solution in water were added. The solution was stirred at rate of 350rpm for 1 h.

[0037] Inventive Surfactant 4: A multiblock copolymer surfactant containing a gradient EOPO block having the structure of 2EH+4PO+[g-3EO5PO]+9EO was prepared as follows. A 15 L conical reaction vessel, equipped with magnetically coupled stirrer head and temperature control, was charged with 218.6 g of 2-ethylhexanol and 6.7 g of 45 % potassium hydroxide aqueous solution. This solution was stirred at 200 rpm and heated up to a temperature of 105 °C. Vacuum was applied to keep the solution at 30 mBar in order to remove the water. Residual water was measured, by means of Karl Fischer titration equipment, to be 830 ppm after two hours at the above-mentioned conditions. The solution was cooled to 100 °C and nitrogen was introduced in the reactor to release vacuum.

[0038] The alkoxylation reaction was carried out in three steps. In the first step 389.5 g of propylene oxide were fed to the solution in 90 min at 135 °C while stirring at 320 rpm. After all the oxide was fed, the reaction was allowed to progress for a period of 0.5 h at 135 °C to digest some of the oxide present. In the second step, 487 g of 1 ,2-propylene oxide and 222 g of ethylene oxide were cofed to the solution at 135 °C while stirring at 320 rpm. in this step, the two oxides feeds were started at the same time with same feed rates. The ethylene oxide was fed in 50 minutes while the propylene oxide feed was completed in 110 minutes. After all the oxides were fed, the reaction was allowed to progress for a period of 6 h at 135 °C to digest all the oxides present. In the third step, 627.3 g of ethylene oxide were fed in 360 min at constant feed rate at 135 °C. After all the oxide was fed, the reaction was allowed to progress for a period of 4h at 135 °C to digest all the oxide present. In both steps, pressure in the reaction vessel was closely monitored and oxide feed constraints were in place to not exceed a pressure of 3.5 bar. The solution was then cooled to 80 °C and 4.8 g of acetic acid 70 % solution in water were added. The solution was stirred at rate of 350rpm for Ih.

[0039] Inventive Surfactant 5: A multiblock copolymer surfactant containing a gradient EOPO block having the structure of 2EH+[g-1.5EO5PO]+9EO was prepared as follows. A 15 L conical reaction vessel, equipped with magnetically coupled stirrer head and temperature control, was charged with 226.1 g of 2-ethylhexanol and 6.5 g of 45 % potassium hydroxide aqueous solution. This solution was stirred at 200rpm and heated up to a temperature of 105 °C. Vacuum was applied to keep the solution at 30 mBar in order to remove the water. Residual water was measured, by means of Karl Fischer titration equipment, to be 580 ppm after two hours at the above-mentioned conditions. The solution was cooled to 100 °C and nitrogen was introduced in the reactor to release vacuum.

[0040] The alkoxy lation reaction was carried out in two steps. In the first step, 898 g of 1,2- propylene oxide and 114 g of ethylene oxide were cofed to the solution at 135°C while stirring at 320rpm. The two oxides feeds were started at the same time with same feed rates. The ethylene oxide was fed in 23 minutes while the propylene oxide feed was completed in 180 minutes. After all the oxides were fed, the reaction was allowed to progress for a period of 6h at 135 °C to digest all the oxides present. In the second step, 681g of ethylene oxide were fed in 360min at constant feed rate at 135 °C. After all the oxide was fed, the reaction was allowed to progress for a period of 4h at 135°C to digest all the oxide present. In both steps, pressure in the reaction vessel was closely monitored and oxide feed constraints were in place to not exceed a pressure of 3.5 bar. The solution was then cooled to 80°C and 4.6 g of acetic acid 70% solution in water were added. The solution was stirred at rate of 350rpm for Ih.

[0041] Inventive Surfactant 5: A multiblock copolymer surfactant containing a gradient EOPO block having the structure of 2EH+[g-3.0EO5PO]+9EO was prepared as follows. A 15 L conical reaction vessel, equipped with magnetically coupled stirrer head and temperature control, was charged with 221.7 g of 2-ethylhexanol and 6.7 g of 45 % potassium hydroxide aqueous solution. This solution was stirred at 200 rpm and heated up to a temperature of 105 °C. Vacuum was applied to keep the solution at 30 mBar in order to remove the water. Residual water was measured, by means of Karl Fischer titration equipment, to be 750 ppm after two hours at the above-mentioned conditions. The solution was cooled to 100 °C and nitrogen was introduced in the reactor to release vacuum. The alkoxy lation reaction was carried out in two steps. In the first step, 889 g of 1,2- propylene oxide and 225 g of ethylene oxide were cofed to the solution at 135 °C while stirring at 320 rpm. The two oxides feeds were started at the same time with same feed rates. The ethylene oxide was fed in 46 minutes while the propylene oxide feed was completed in 180 minutes. After all the oxides were fed, the reaction was allowed to progress for a period of 6 h at 135 °C to digest all the oxides present. In the second step, 634 g of ethylene oxide were fed in 360min at constant feed rate at 135 °C. After all the oxide was fed, the reaction was allowed to progress for a period of 4h at 135 °C to digest all the oxide present. In both steps, pressure in the reaction vessel was closely monitored and oxide feed constraints were in place to not exceed a pressure of 3.5 bar. The solution was then cooled to 80 °C and 4.7 g of acetic acid 70 % solution in water were added. The solution was stirred at rate of 350 rpm for 1 h.

[0042] Physical properties were then studied for the inventive surfactants as shown in Table 2. Hydroxyl number as KOH was measured using ASTM D4274D. Number average molecular weight was calculated as: 56100 / OH number * polymer functionality (one in this case).

[0043] Example 2: Surfactant Performance

[0044] In this example, surfactant properties were analyzed to quantify inventive surfactant performance relative to the comparative sample. Results are plotted in Table 3. Surfactant performance was first assessed by measuring the cloud point at 1 wt% aqueous concentration and critical micelle concentration (CMC) for each alkoxylate product.

[0045] Table 1 summarizes the results. A new series of 2EH+[ ]+9EO surfactants demonstrated a low CMC of about lOOppm, which are much lower than Comp. Surfactant 1. This new approach allows a reduction of CMC by approximately 1 order of magnitude, while maintaining similar surfactant properties, such as surface tension, pour point, dissolution and contact angle.

[0046] Table 3: Physical properties for surfactant examples

[0047] Example 3: Biodegradability test

[0048] The ready biodegradability of these new surfactants was evaluated according to the OECD Guideline No. 301D: Manometric Respirometry Test. Biodegradation was evaluated in duplicate reaction mixtures containing a defined mineral medium which was inoculated with activated sludge biosolids (30 mg / L dry wt.) from the City of Midland (Michigan, USA) wastewater treatment plant. Biodegradation of a reference substance (aniline) was also measured in duplicate to evaluate the viability of the inoculum and to determine precision in the respiration measurements. Oxygen consumption and carbon dioxide evolution in the continuously-stirred (22 °C) reaction mixtures was measured at 6 hr intervals over the 28 day test period using a respirometer. Respiration in the biodegradation reactions was corrected for that occurring in inoculum blanks containing only the inoculated mineral medium, and this net respiration was compared to the ThOD and theoretical carbon dioxide yield (ThCO2) for each substance to determine percent biodegraded based on oxygen consumption (DO2) and carbon dioxide evolution (DC02).

[0049] Inventive surfactants pass level (60% DO2) in 28 days, showing these materials meet current OECD criteria for classification as “readily biodegradable”.

[0050] Example 4: Laundry application test

[0051] In this example, surfactant formulations were prepared and analyzed for the ability to remove sebum from fabrics. Primary cleaning testing was done using a Tergitometer with six parallel, 2L canisters, each filled with IL of 120ppm, Ca:Mg 3:1 hardness adjusted water and the wash temperature is set to 86 °F (30 °C). The test detergent formulations were added at a dosage level of 0.3 g / L and the tergitometer spindle speed was adjusted to 85 rpm. Four 5cm x 5cm testing fabrics of PC-S-94 dust sebum swatches from Test fabrics were added into each canister and were washed for 30 minutes. Then the fabrics were removed, wash solutions were drained and hardness adjusted water was added to the canisters. The washed fabrics were added back to the canisters and rinsed for 3 minutes. They were then removed and dried in a drier in the “warm” setting for 60 minutes.

[0052] Color space analysis was used to determine the effectiveness of stain removal. The L*, a* and b* values of the stained fabrics were measured pre (US) and post wash (WS) with a Mach 5+ spectrophotometer from Colour Consult. The L*, a* and b* values for the unwashed, unstained polycotton fabric (UF) was measured to use in the SRI calculations as follows: where: US = Unwashed stain area, UF = Unwashed (unstained) fabric area, WS = Washed stain area. AE*(US-UF) = Delta-E color difference between the unwashed stain and the unwashed fabric, and AE*(WS-UF) = Delta-E color difference between the washed stain and the unwashed fabric. The value delta E* is calculated as: AE* = (AL2+ Aa2+ Ab2)°5

[0053] This test was repeated twice and the data from both tests were combined to compare the performance of the detergents with the different testing surfactants.

[0054] Laundry unit dose formulation, ingredients listed in the order of addition are provided in Table 4, with 55% active, and pH adjusted to -8-8.5. Results are shown in Tables 5 and 6.

[0055] Example 5: Hard surface cleaning test

[0056] In this example, surfactants are used to generate a cleaning formulation for the removal of soil from hard surfaces (i.e., vinyl tiles) and evaluated according to the Gardner scrub test (as outlined in ASTM D-2486). Results were quantified by the gray value of a scrubbed area after treatment. Cleaning % was calculated as (Gray value after cleaning - Gray value for soiled tile) / (Gray value for unsoiled tile- Gray value for soiled tile)xl00%.

[0057] The soiling formulation included 8.15 wt% soybean oil, 27.62 wt% triglycerides, 3.17 wt% carbon black, and. 61.06 wt% VM&P naphtha. Soil was applied to the tiles and tested as noncrosslinked (room temperature (25°C) dry for 12-24 hours) or crosslinked (71 °C oven for 18 hours, followed by cool to room temperature). Cleaning formulations were prepared based on the recipe for generic formulation shown in Table 7, and then visually observed for stability and tested with the scrubbing test. Results are shown in Table 8.

[0058] For hard surface cleaning applications, Comp. Surfactant 1 is used as a commercial benchmark for hard surface cleaning performance. The higher Cleaning % values mean better cleaning efficiency. The inventive surfactants including the random or gradient copolymer blocks exhibit comparable or improved cleaning performance with respect to Comp. Surfactant 1 for both the non-crosslinked tiles and crosslinked tiles, with Inv. Surfactant 5 demonstrating the best cleaning performance. While the foregoing is directed to exemplary embodiments, other and further embodiments may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

Claims1. A surfactant composition, comprising: one or more multiblock copolymer surfactants having a general formula of R-O-[AO]x[AOa EOb]y[EO]c where R is a linear or branched, saturated or unsaturated C6 to C18 carbon chain; AO is a C3 to C6 alkylene oxide and x ranges from 0 to 5; y is at least 1 , [AOaEOb] designates a block copolymer where a ranges from 1 to 20, b ranges from 0.5 to 3.5; and c ranges from 1 to 50.

2. The composition of claim 1, wherein [AOaEOb] is a gradient block copolymer.

3. The composition of claim 1, wherein [AOaEOb] is a random block copolymer.

4. The composition of claim 1, wherein the one or more multiblock copolymer surfactants has a ratio of a / b that ranges from 2 to 30.

5. The composition of claim 1, wherein the one or more multiblock copolymer surfactants has a general formula of:R- O-[POaEOb]y[EO]cwhere R is a linear or branched, saturated or unsaturated C6 to C18 carbon chain; y is at least 1 and designates a block copolymer of PO and EO, a ranges from 1 to 20, b ranges from 0.5 to 3.5, and the ratio a / b ranges from 2 to 30; and c ranges of 1 to 50.

6. The composition of claim 1 , wherein the one or more multiblock copolymer surfactants are generated by: polymerizing, in the presence of an alcohol R-OH, one or more C3 to C6 alkylene oxides to generate a first product; polymerizing, in the presence of the first product, a mixture of one or more alkylene oxides and ethylene oxide to generate r, wherein the one or more alkylene oxides and ethylene oxide are co-fed at a / b ratio 2 to 30 to generate a second product; and polymerizing, in the presence of the second product, ethylene oxide.

7. A method of using the surfactant of any previous claim, comprising using the composition to clean a substrate.

8. The method of claim 7, wherein the substate is a textile or solid surface.

9. A method of preparing a multiblock copolymer surfactant having a general formula of:R- O-[AO]x[AOa EOb]y[EO]cwhere R is a linear or branched, saturated or unsaturated C6 to Cl 8 carbon chain; AO is a C3 to C6 alkylene oxide and x ranges from 0 to 5 ; y is at least 1 , [AOaEOb] designates a block copolymer where a ranges from 1 to 20, b ranges from 0.5 to 3.5; and c ranges from 1 to 50; the method comprising: polymerizing, in the presence of an alcohol R-OH, one or more C3 to C6 alkylene oxides to generate a first product; polymerizing, in the presence of the first product, a mixture of one or more alkylene oxides and ethylene oxide to form block [AOaEOb] and generate a second product; and polymerizing, in the presence of the second product, ethylene oxide to generate the multiblock copolymer surfactant.

10. The method of claim 9, wherein polymerizing the mixture of one or more alkylene oxides and ethylene oxide to form block [AOaEOb] comprises co-feeding the one or more alkylene oxides as a primary feed stream and the ethylene oxide as a secondary feed stream to a polymerization zone, wherein the time period for feeding from the secondary feed stream is less than the time period for feeding the primary stream.

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