AQUEOUS EMULSION COMPRISING THE REACTION PRODUCTS OF A VINYL ACID MONOMER AND A SECOND COPOLYMERISABLE MONOMER

Abstract: High acid content latexes can be produced through the use of novel polyethyleneoxy sulfonates surfactants. An aqueous emulsion can be produced from the reaction pro­ duct of vinyl acid monomer and another copolymerizable monomer or monomers. The vinyl acid monomer being present in an amount equal to about 5% to about 50% by weight based on total weight of the monomers and the sur­ factant is present in an amount equal to about 0.1 to about 10 weight percent based on the total weight of monomers and is represented by the formula: R₁R₂O(CH₂CH₂O) n-1 CH₂CH₂SO₃Me wherein: R₁ is an alkyl or dialkyl having at least 6 carbon atoms; R₂ is hydrogen or an aryl group; n is at least 3; and Me is NH₄, Na, Li or K. High solids content aqueous vinyl acetate emulsions having long term stability are provided by polymrizing vi­ nyl acetate in the presence of the above surfactant and water wherein R₂ is an aryl group and n is greater than 9. The quantity of water is predetermined so as to produce a latex having at least 40% solids.

Description: POLYETHYLENEOXY SULFONATE SURFACTANTS BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to novel salts of polyethyleneoxy sulfonates, their method of manufacture and their use as surfactants in high acidity latexes, such as latexes of copolymers of acrylic acid and in polyvinyl acetate emulsions. Description of the Prior Art Surfactant sold under the trademark Triton by Rohm & Haas Co. and Alipal SE-463 by GPF Corp. are alkyl aryl polyether sulfonate, sodium salts. These sulfonates offer many diversified surfactant properties not commonly encountered in a single compound. They out perform comparable sulfates in offering resistance to decomposition under both highly acidic and basic conditions, thus being suitable in metal cleaning applications for either acid pickling baths or alkaline cleaning formulations. Their excellent compatibility with alkaline detergent builders and their excellent emulsifying character with fats, greases, oils and gelatins afford many applications possibilities in lime soap formulation, the film coating industry, as dye leveling agents, post-latex stabilizers and in emulsion polymerization. A major application for this type of surfactant is a shampoo base for the cosmetics industry where it finds wide applicability because of its detergent, lathering and solubilizing properties. However, it has now been found that in certain applications, as for example the production of high acid level latexes, such as, acrylic and methacrylic acid copolymer latexes containing in excess of 10% acrylic acid, coagulation occurs. The problem becomes most acute when attempting to store the latex for over a week. The low shelf life of these latexes renders them unusable in many industrial applications because of the commonly encountered need to store the latex before further processing can be commenced. It has also been found that in certain applications, as for example the production of high solids content, poly vinyl acetate emulsions, coagulation occurs when attempting to produce emulsions having less than 40% water. The production of high solids content latexes has long been considered to be desirable, the advantage being the maximizing use of production equipment and the minimization of the quantity of water which must be shipped in a latex. High solids content emulsions tend to coagulate immediate or become unstable after relatively short periods of storage. For example, in the production of vinyl acetate, the preparation of high solids content emulsions has necessitated the use of phosphate type surfactants, protective colloids and/or special processing, as disclosed for example in U.S. Patent 3,637,563. The heretofore employed procedures and formulations has proven to be inadequate because of unfavorable economic factors and/or environmental considerations. Although it would be highly desirable to eliminate the use of a protective colloid thereby providing a cost reduction in the system, repeated attempts to produce such systems have proven unsuccessful. U.S. Patent 3,637,563 which is directed to the production of high solid aqueous polymer emulsions suggests the use of surfactants such as, alkylphenoxy poly (ethyleneoxy) ethanols, as well as the use of higher molecular weight sulfates and sulfonates. Among the materials specifically referred to in the aforenoted patent are alkylphenoxy poly (ethyleneoxy) ethanols which contain from about 30 to about 100 ethyleneoxy units, and typical anionic surfactants, e.g., an ethoxylated higher fatty acid which has also been sulfonated. In order to produce a stable emulsion employing of the disclosure of 3,637,563, it is necessary to employ one or more protective colloids, particularly when a reflux type polymerization is carried out by using vinyl acetate, or the like, as part of the monomer charge. Included among such materials are either linkage containing protective colloids, such as hydroxy methyl cellulose, hydroxy ethyl cellulose, ethyl hydroxy ethyl cellulose, carboxy methyl cellulose, ethoxylated starch derivatives, and the like. Other protective colloid forming substances, i.e., those containing no ether linkages, are also disclosed as being usable, either alone or together with the aforementioned ether linkagecontaining materials. SUMMARY OF THE INVENTION It has now been found that improved surfactants can be produced from alkyl aryl poly(ethyleneoxy) sulfonates, represented by the formula: EMI3.1 wherein R is an alkyl or a dialkyl group having at least 6 carbon atoms; n is greater than 9; and Me is a monovalent cation, preferably Na, NH4, K or Li. High solids content vinyl acetate latexes having high shelf-lives can be produced without the need to resort to special processing or protective colloids by employing the aforenoted sulfonates. In accordance with the present invention, an improved high solids content aqueous vinyl acetate emulsion is provided by polymerizing vinyl acetate in the presence of the surfactant and water. The quantity of water is predetermined so as to produce a latex having at least 40% solids. It has also been found that high acid content latexes can be produced through the use of novel polyethyleneoxy sulfonates surfactants in accordance with the present invention. An aqueous emulsion is produced from the reaction product of vinyl acid monomer and at least a second copolymerizable monomer, said vinyl acid monomer being present in an amount equal to about 5% to about 50% by weight based on total weight of said vinyl acid monomer and said at least a second copolymerizable monomer. The surfactant being present in an amount equal to about 0.1 to about 10 weight percent based on the total weight of said vinyl acid monomer and said at least a second copolymerizable monomer and is represented by the formula: R1R2(CH2CH20 )n1CH2CH2S03Me wherein: R1 is an alkyl having at least 6 carbon atoms, R2 is hydrogen or an aryl group; n is at least 3; and Me is NH4, Na, Li or K. DESCRIPTION OF THE PREFERRED EMBODIMENTS In order that those skilled in the art can more fully understand the present invention, the following detailed description and examples are provided. These examples are intended solely for the purpose of illustrating the invention, and are not to be construed as expressing limitations unless so set forth in the appended claims. All parts and percentages are by weight, unless otherwise stated. Salts of non-ionic surfactants of the type sold under the trademark ALIPAL, by GAF Corporation, are generally recognized as having utility in emulsion polymerization. These surfactants are represented EMI4.1 Commercial surfactants include ALIPAL SE-463, wherein R is C8H17, X is NaS03 and n is 3. The surfactants of Table I can all be represented by the formula: R2-(CH2CH20 1 CH2CH2S03Na Alfol is a trademark of the Continental Oil Company. In Alfol 1012 + 3 E.O. Sulfonate, R2 is a straight chain alcohol having an average of between 10 and 12 carbons and n is 3. In Alfol 12 + 4 E.O. Sulfonate, R2 is a straight chain alcohol having an average of between 10 and 12 carbons and n is 3. In Alfol 12 + E.O. Sulfonate, R2 is a straight chain having 12 carbons and n is 4. In Alfol 1214, R2 is straight chain alcohol having an an average of 12 to 14 carbons and n is 6. In oxotridecyl + 4.2 E.O. Sulfonate, R2 is an oxotridecyl group and n averages about 4.2. In emulphogene BC-720, R2 is C12H27; and n is greater than about 9. In Igepal CO-630, R is nonyl phenoxy and n is 9. In Igepal C0-850, R is nonyl phenoxy and n is 20. In Igepal C0-890, R is nonyl phenoxy and n is 40. Emulphogene and Igepal are registered trademarks of GAF Corporation and Alfol is a trademark of Continental Oil Company. Table I compares the use of various surfactants in the emulsion polymerization of vinyl acetate, surfactants having 9 or less repeating ethyleneoxy groups were found to be unable to give the results attainable with longer polymer chains. In one isolated, non-representative run, the Igepal 850 sulfonate failed to give the desired result. It is seen from the comparison in Table II that the use of various sulfonate surfactants in the emulsion polymerization methacrylic acid copolymers produces latexes having shelf-lives in excess of several months, whereas an analogous sulfate surfactant was unable to give the desired results. Basically, the technology of producing the sulfonates involves initially transforming the terminal alcohol functionality of a nonionic surfactant to a terminal chloride using thionyl chloride, or other chlorinating agent as follows: EMI6.1 The chloride terminated material is then converted to the sodium sulfonate, using sodium sulfite, as follows: EMI6.2 Looking now in greater detail to the chemistry of the production of the surfactants of the present invention it is noted that the synthetic approach to the production of poly ether sulfonate type surfactants involves the reaction of chlorine capped nonionics with sodium sulfite, as disclosed in patent 2,115,192. EMI6.3 The sulfonate functionality has much less tendency to hydrolize in solutions of low pH than does an analagous surfactant with a sulfate functionality. EMI7.1 (sulfonate) (Sulfate decomposition) The ether sulfonates are noted to contain both an ethoxylated nonionic portion and a sulfonic acid anionic portion. In the systems of Table I, the alkyl aryl poly ethoxy sulfonates were employed for producing poly vinyl acetate latexes, without the incorporation of a protective colloid. In each case, the alkyl sulfonates failed to produce a stable vinyl acetate latex in the absence of a protective colloid. The criticality of the length of the poly ethoxy group is evident from the failure of the Igepal 630 sulfonate to produce a stable latex. By way of contrast, the sulfonate of Igepal C0-850 formed very stable vinyl acetate emulsions at 55 and 62% solids. The latexes exhibited good mechanical stability, no coagulum, low viscosity and excellent shelf life. The latex produced from the sulfonate of Igepal C0-890 coagulated after 24 hours storage, the probable contributing factor being low conversion to the sulfonate form. Looking now in greater detail to the chemistry of the production of the surfactants of the present invention it is noted that the synthetic approach to the production of poly ether sulfonate type surfactants involves the reaction of chlorine capped nonionics with sodium sulfite, as disclosed in patent 2,115,192. EMI7.2 The reaction requires high temperature -- 155-17O0C being the most desirable range -- and pressures of 70-115 psig. To attain over 90% conversion of the chlorine terminated nonionics, reaction times of about 20 hours are typical. The rate of sulfonation appears to be 100 to 500 times the rate of hydrolysis under proper reaction conditions such that good conversions can be expected with most nonionic types under the reaction conditions to be defined in this report. The competing hydrolysis reaction results in a portion of OH terminated nonionics being present in the reaction product as depicted below. EMI8.1 (Hydrolysis) The sulfonate method of preparation is well-known to those skilled in the art as represented by patents such as U. S. 4,091,014, 2,209,911 and 2,148,432. U. S. Patent 4,091,014 is noted to disclose the manufacture of ether sulfonates, by sulfonating alcohols such as: EMI8.2 where n is an integer such as 3, 4 and 5. U. S. Patent 2,209,911 discloses the production of alkylated phenoxy ether halides, while 2,148,432 discloses the method of-producing alkyl phenoxy polyethylene oxide sulfonates from the corresponding alkyl phenoxy poly ethoxy halide. It should thus be evident that the sodium salts of polyether sulfonates of the present invention can be made in accordance with the teachings of the aforenoted patents. Whereas the prior art typically is primarily concerned with an sulfonates having 2, 3 or 4 ethylene oxide units, one aspect of the instant invention is directed to higher values of "n". It appears that the ethylene oxide chain length has an effect on the rate of the sulfonation reaction, based on the unreacted sulfite present in a series of identical runs after a 10 hour reaction period at elevated temperature. It is believed that the steric hinderance of the polyethoxy group is a limiting factor in the sulfonate conversion and precludes adequate conversion of n=40 polyethyleneoxy to useful sulfonates. The upper limit for the length of the ethylene oxide claim is not as critical as the lower limit. An upper limit for n, of about 30 is preferred, however, to the extent such a material could be made and isolated, an n value in excess of 40 could be used. It is preferable to balance the properties of the alkyl group and the polyethoxy group. Therefore, the alkyl group should have between 6 and 18 carbons and preferably no more than 12 carbons. While dialkyl groups can be employed, the number of carbons in each alkyl group should not be greater than 12. The conversions are listed below. Igepal CO Series Conversions at 1600C. C H - -(OC H ) SO Na 9 12 2 4 n 3 Conversion Conversion Name n of-Sulfite of Sulfonate Igepal C0-630 9 92 71 Igepal CO-730 15 48 37 Igepal CO-850 20 76 34 Although a comparison of sulfonate conversion by methylene blue activity may not be accurate through the Igepal CO series, the presence of unreacted sulfite indicates a reduced reactivity of the chlorine terminated nonionic with increasing chain length whatever the product distribution from the chloride might be. Inclusion of a more reactive halogen (NaBr, NaI) can be employed to improve the nonionic reactivity by in situ halogen exchange. EMI10.1 Alternatively, the charge of Na2S03 can be increased to increase the reactive collison frequency. In the case of Igepal C0-850 at 50% excess of sulfite would result in an increase in salt content in the product of only 2.0%, thus increasing the salt content in the final product but to a tolerable level. 1. Preparation of Alfol 1012 + 3 EO Ether Sulfonate a. Chlorination A 1 liter r.b. flask equipped with mechanical stirrer, thermometer, dropping funnel and condenser adapted to a caustic scrubber was charged with 600 gms of thionyl chloride (2.0 moles). To it were added 286 gms of thionyl chloride (2.4 moles) maintaining the reaction mixture 550C during addition. The mixture was then heated to 1000C for 1 hour, the condenser removed and heated to 100-1100C with an air purge for 2-1/2 hours. The appearance of the chloride was improved by the addition of 3 gms of 30% H202 at 80 0C and heating to 100-110 0C for 15 minutes (VCS 15 initial; VCS 9.5 final). Analysis: Cl 11.67/11.2 (actual/theory). b. Sulfonation A charge of 420 gms of the Alfol 1012 + 3 EO chloride (1.32 moles) was combined with 175 gms of Na2S03 (1.39 moles), 1000 ml of distilled water and 4.5 gms of 50% NaOH in a 1 gallon autoclave and reacted at 160 50C for 10 hours. Stirring speed was 1750 rpm. The product was cooled to 400C was discharged. It was a viscous, light yellow liquid (VCS 4+) having an ethlenic Blue (M.B.) activity of 25.7% (80.8%) based on a molecular weight of 386, a chloride content of 5.27% and a pH of 5.3 (20% solution). The excess sulfite was removed by adding 16.5 gms of 30% H202 at 30-400C and the pH adjusted to 7.2 with 9.5 gms of 50% NaOH. The final product properties include 1.83% Na2S04, 4.65% NaCl and 36.2% total solids. 2. Preparation of Alfol 12+4 EO Ether Sulfonate a. Chlorination A 1 liter round bottom flask equipped with mechanical stirrer, thermometer, dropping funnel and condenser adapted to a caustic scrubber was charged with 500 gms (1.38 moles) of Alfol 12 + 4 EO. To it was added 205 gms (1.73 moles) of thionyl chloride at a rate which conveniently maintained the temperature below 550C. The mixture was then heated to 100-1050C for 4 hrs and the disappearance of the IR absorption at 3500 cm-1 (OH) monitored. When the OH band had been removed, the condenser was removed and the chlorosulfite heated to 100-110 C with an air purge to remove the SO2 formed. The air purging and heating were continued for 4 hours until the inorganic chloride had dropped to 0.07%. Analysis: Cl, 9.34/933 (actual/theory). b. Sulfonation A charge of 440 gms of the Alfol 12 + 40 EO chloride (1.16 moles) was combined with 158 gms of Na SO (1.25 moles), 880 gms of distilled water and 8 gms of 50% N2aOH3in a 1 gallon autoclave and reacted at 165 50C for 20 hours. Stirring speed was 1750 rpm. The product was cooled to 600C and discharged. It was a viscous, clear liquid (VCS 2+) which solidified on standing overnight (it has a m.pt. of 280C and if diluted to a M.B. activity of 19% remains a liquid at room temperature). Preliminary data indicated a methylene blue activity of 28.8% (72.7%) based on a molecular weight of 448, and a chloride content of 4.32% (84%). The excess sulfite was removed by adding 22 gms stirring at room temperature (a starchiodine test confirmed the absence of sulfite) and the pH was adjusted to 7.3 to 4.5 gms of 50% NaOH. Final product properties include 1.87% Na2S04, 2.95% NaCl, 40.2% total solids, 4.76% nonionics. 3. Preparation of Alfol 1214 + 6 EO Ether Sulfonate a. Chlorination A 2 1. flask equipped with mechanical stirrer, thermometer, dropping funnel and condenser adapted to a caustic scrubber was charged with 752 gms of Alfol 1214 + 6 EO (2.0 moles). To it were added 286 gms of thionyl chloride (2.4 moles) maintaining the reaction temperature below 550C. When the addition was completed, the reaction mixture ws heated to 1000C for 1/2 hour, the condenser removed and heating at 100-110 C continued for three hours under an air purge (subsurface) to remove 502. The appearance of the chloride was improved by the addition of 40 gms of 30% H202 added at 65 C followed by heating to 900C for 15 min. (VCS 13.5 initial; VCS 7 final). Analysis: Cl 8.61/9.00 (actual/theory). b. Sulfonation A 10 gm portion of the above chloride was dissolved in ethanol and titrated to a pH of 10., with 0.1 N NaOH (12.6 ml). A charge of 711 gms of the Alfol 1214 + 4 EO chloride (1.80 moles) was combined with 238 gms of Na2S03 (1.89 moles), 1500 ml distilled water and 12 gms of 50% NaOH in a 1 gallon autoclave and reacted at 160 50C for 20 hours at 1750 rpm. The product was cooled to 4O0C and discharged. It was a layer system initially (viscous yellow liquid -- top layer hazy, botton layer clear) which solidified on standing. As such it had a M.B. activity of 24.4% (72.2%) based on a molecular weight of 462, a chloride content of 4.686 (101%) and a pH of 6.6 (20% solution). The excess sulfite was removed by the addition of 54 gms of 30% H202 and the pH was adjusted to 7.2 (20% solution) by addition of 10 gms 50% caustic. The final product properties include 2.68% Na2S04, 4.50% NaCl and 39.5% total solids. The sample is a white solid at room temperature at this concentration. Dilution with distilled water to a M.B. activity of 13.3% affords a clear, yellow, liquid product. 4. Preparation or oxo Tridecyl + 4.2 EO Ether Sulfonate a. Chlorination A 2 1. flask equipped with mechanical stirrer, thermometer, dropping funnel and condenser adapted to a caustic scrubber was charged with 800 gms of emulphogene BC-420 (2.4 moles. To it was added 343 gms of thionyl chloride (2.88 moles) maintaining the temperature below 550C during addition. The reaction mixture was then heated to 100-1050C continued for 1-1/2 hours with an air purge (subsurface) to remove S02. The appearance of the chloride was improved by the addition of 30 gms of 30% H202 at 700C and heating to 1000C for 1/2 hour (VCS 18 initial; VCS 12 final). The final inorganic chloride was 0.1%. Analysis: Cl 9.91/10.1 (actual/theory). b. Sulfonation A charge of 445 gms of the Emulphogene BC-420 chloride (1.27 moles) was combined with 168 gms of Na2S03 (1.33 moles), 1000 ml of distilled water and 10 gms of 50% NaOH in a 1 gallon autoclave and reacted at 165 50 0C for 20 hours at 1750 rpm. The product was cooled to 400C and discharged. It was a viscous gelatenous material havig a M.B. activity of 22.9% (70.1%) based on a molecular weight of 418, an inorganic chloride content of 4.68% and a pH of 6.7 (20% solution). The excess sulfite was removed by the addition of 72 gms of 30% H O and the pH adjusted to 7.5 with 9 gms of 50% NaOH. The final2 2 product properties include 2.36% Na SO , 4.41% NaCl and 34.6% total solids. It offers a clear yellow solution with 25% ethanol. Dilutions to 13% M.B. activity with water, also provide a clear liquid above 700C which, however, clouds on slight cooling. 5. Preparation of Oxo-Tridecyl + 4.2 EO Ether Sulfonate a. Chlorination A 2 1. flask equipped with mechanical stirrer, thermometer, dropping funnel and condenser adapted to a caustic scrubber was charged with 800 gms of Eulphogene BC-420 (2.4 moles. To it were added 343 gms of thionyl chloride (2.88 molesO maintaining the temperature below 550C during addition. The reaction mixture was then heated to 100-1050C for 1/2 hour, the condenser removed and heating to 100-1050C continued for 1-1/2 hours with an air purge (subsurface) to remove S02. The appearance of the chloride was improved by the addition of 30 gms of 30% H202 at 700C and heating to 1000C for 1/2 hour (VCS 18 initial; VCS 12 final). The final inorganic chloride was 0.1%. Analysis: Cl 9.91/10.1 (actual/theory). b. Sulfonation A charge of 445 gms of the Emulphogene BC-420 chloride (1.27 moles) was combined with 168 gms of Na2S03 (1.33 moles), 1000 ml of distilled water and 10 gms of 50% NaOH in a 1 gallon autoclave and reacted at 165 500C for 20 hours at 1750 rpm. The product was cooled to 400C and discharged. It was a viscous gelatenous material having a M.B. activity of 22.9% (70.1%) based on a molecular weight or 418, an inorganic chloride content of 4.68% and a pH of .7 (20% solution). The excess sulfite was removed by the addition of 72 gms of 30% H202 and the pH adjusted to 7.5 with 9 gms of 50% NaOH. The final product properties include 2.36% Na2S04, 4.41% NaCl and 34.6% total solids. Dilutions to 13% M.B. activity with water also provide a clear liquid above 7O0C which clouds on slight cooling. 6. Preparation of Nonylphenol + 9 EO Ether Sulfonate a. Chlorination A 3 1. flask equipped with mechanical stirrer, thermometer, dropping funnel and condenser adapted to a caustic scrubber was charged with 2000 gms of Igepal CO-630 (3.28 moles). To it were added 540 gms of thionyl chloride (4.54 moles) maintaining the reaction temperature below 600C. When the addition was completed the reaction mixture was heated to 1200C for 1/2 hour at which time an IR revealed no OH band at 3500 cam¯1. The condenser was removed and heating at 100-1100C continued with removal of SO by a subsurface nitrogen purge. The heating was continued fo? a total of 7 hours whereupon conversion to the chloride was essentially complete. The appearance of the chloride was improved by bleaching with 50 gms of 30% H202 at 70-9O0C for 15 minutes (VCS 18 initial, VCS 13 final). Analysis: Cl 5.51/5.63 (actual/theory). b. Sulfonation A charge of 638 gms of the Igepal CO-630 chloride (1.0 mole) was combined with 131 gms of Na2S03 (1.0 mole), 1200 ml of distilled water and 6.0 gms of 50% NaOH in a 1 gallon autoclave and reacted at 160 50C for 20 hours at 1750 rpm. The product was cooled to 400 and discharged. It was a very viscous clear yellow liquid having a M.B. activity of 25.5% (71.4%) based on a molecular weight of 698, a chloride content of 2.98% (101%) and a VCS of 2. The excess sulfite was removed by the addition of 16 gms of 30% H202 and the pH adjusted to 7.4 with 9 gms of 50 NaOH. The final product properties include 1.48% Na2S04, and 40.3% total solids. 7. Preparation of Nonylphenol and 20 EO Ether Sulfonate The procedure employed for producing the nonylphenol 9 EO Ether sulfonate can be followed using Igepal C0-850 and thionyl chloride in a 1 to 1.5 mole ratio in the chlorination procedure and a 1 to 1 Igepal C0-850 chloride to sodium sulfite mole ratio in the sulfonation procedure. 8. Preparation of Nonylphenol and 40 EO Ether Sulfonate The procedure for producing the nonylphenol 9 E.O. ether sulfonate can be followed, using Igepal CO-890 in approximately a 1 to 1.5 mole ratio with thionyl chloride. The sulfonation step can employ the resultant chloride of Igepal CO-890 in a 1 to 4 mole ratio with sodium sulfite. The theory of the invention is not fully understood and discussions of the theory of operation are for the purposes of contributing clarity and understanding and are not intended by way of limitation. Table I sets forth experimental results of the production of high solids content vinyl acetate emulsions using various surfactants. The term "high solids content" as employed herein means emulsions in which the solids constitutes at least 40% by weight of the composition. The sodium sulfonate of the surfactants sold under the trademark Igepal C0-630 by GAF Corporation was found to coagulate during its formulation into a vinyl acetate latex but only during the last stages of addition thus showing a higher level of compatibility with vinyl acetate than many other surfactants, but, nevertheless, failing to produce the required results. TABLE I POLYVINYL ACETATE VINYL ACETATE MECHANICAL BROOKFIELD LATEX SURFACE SURFACTANT LATEX % SOLIDS COAGULUM STABILITY VISCOSITY SOLIDS PH TENSION Igepal CO-630 - Sulfonate 55 100%* -- -- -- -- - Igepal CO-850 - Sulfonate 55 None OK 70(1-60) 56.8 3.0 43.4 Igepal CO-850 - Sulfonate 55 5.0 gns OK 95(1-60) 56.6 6.9 38.5 Igepal CO-850 - Sulfonate 55 None N.G. 850(3-60) -- -- 50.0 Igepal CO-850 - Sulfonate 55 None OK 85(1-60) 55.6 3.0 42.0 Igepal CO-850 - Sulfonate 55 None OK 385(1-12) 62.8 2.9 44.0 Igepal CO-890 - Sulfonate 62 Very Slight** OK 120(1-30) 56.2 3.1 47.0 (Alfol 1012 + 3 E.O.) Sulfonate 55 100% -- -- -- -- - (Alfol 12 + 4 E.O.) Sulfonate 55 100% -- -- -- -- - (Alfol 1214 + E.O.) Sulfonate 55 100% -- -- -- -- - Emulphogene BC-720 Sulfonate 55 100% -- -- -- -- - (Oxotridecyl + 4.2 E.O.) Sulfonate 55 100% -- -- -- -- - In final states of addition * Coagulated after 24 hours storage ** Preparation of a Butyl Acrylate-Styrene-Methacrylic Acid (50-25-25) Terpolymer Latex To a 2 liter resin kettle was added 9.8 g. of the desired surfactant (based on 100% methylene blue activity), 291.5 g. water (including water present in the surfactant, and 0.5 g. potassium persulf ate. Nitrogen purge was started immediately. To the kettle was added 37.5 g. butyl acrylate, 19.0 g. styrene, and 19.0 g. methacrylic acid. The kettle was then heated with stirring to 75-80 C. While the kettle was being heated to the final temperature, a pre-emulsion was prepared which contained 2.8 g. surfactant, 139.2 g. water, 0.5 g. potassium persulfate, 112.5 g. butyl acrylate, 56.0 g. styrene, and 56.0 g. methacrylic acid. The pre-emulsion was transferred to the pressure-equalizing addition funnel. The funnel was fitted with a mechanical stirrer, and was attached to the kettle. When the kettle reached 75-800C, the stirred pre-emulsion was added dropwise over a 3 hour period. The 75-80 range was maintained throughout. When addition was complete, heat was continued an addtional 40 minutes to insure complete reaction. The kettle was then cooled to room temperature and the latex was discharged through a 60 mesh sieve. Preparation of a Butyl Acrylate-Styrene Methacrylic Acid (30-30-40) Terpolymer Latex To a liter resin kettle was added 9.8 g. of the desired surfactant (based on 100% methylene blue activity), 291.5 g. water (including water present in the surfactant, and 0.5 g. potassium persulfate. Nitrogen purge was started immediately. To the kettle was added 28.3 g. butyl acrylate, 28.3 g. styrene, and 37.75 9. methacrylic acid. The kettle was then heated with stirring to 75-80 . While the kettle was being heated to the final temperature, a pre-emulsion was prepared which contained 2.8 g. surfactant, 139.2 g. water, 0.5 g. potassium persulfate, 84.2 g. butyl acrylate 84.2 g. styrene and 112.25 g. methacrylic acid. The pre-emulsion was placed in a pressure-equalizing additional funnel. The funnel was fitted with a mechanical stirrer, and was attached to the kettle. When the kettle reached 75-80 the stirred pre-emulsion was added dropwise over a 3 hour period. The 75-800' range was maintained throughout. When addition was complete, heat was continued an additional 40 minutes to insure complete reaction. The kettle was cooled to room temperature and the latex was discharged through a 60 mesh sieve. Preparation of Methacrylic Acid-Butyl Acrylate (60-40) Latex To a 2 liter resin kettle was added 260.5 g. water, 40.75 g. Igepal CO-630 sulfonate (24.5% methylene blue activity), and 0.5 g. potassium persulfate. Nitrogen purge was started immediately. To the kettle was added 45.6 g. methacrylic acid and 30.4 g. butyl acrylate. The kettle was then heated to 75-80 . While the kettle was being heated to the final temperature, a pre-emulsion was prepared which contained 11.75 g. Igepal CO-630 sulfonate, 130.25 g. water, 0.5 g. potassium persulfate, 134.4 g. methacrylic acid, and 89.6 g. butyl acrylate. The pre-emulsion was placed in a pressure-equalizing addition funnel fitted with a mechanical stirrer. When the kettle temperature was reached, dropwise addition of the pre-emulsion was begun. Although addtion was to proceed over 3 hours, the reaction was stopped after 30 minutes because of complete coagulation. The latexes which can be produced can have in excess of 5% of an acidic monomer. Although, specific reference has heretofore been made to methacrylic acid, polymerizable ethylenically unsaturated monocarboxylic and polycarboxylic acids as well as the available anhydrides, nitriles, unsubstituted amides and substituted (including N-substituted) amides of said acids, can also be employed as comonomers. More particularly, monethylenically unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, ethacrylic acid and crotonic acid, monoethylenically unsaturated dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid and citraconic acid, and monoethylenically unsaturated tricarboxylic acids such as aconitic acid can be employed, as can their halogen-substituted (e.g., fluroro- chloro- and bromosubstituted) derivates, e.g. -chloroacrylic acid, and the anhydrides of these acids, e.g., -chloroacrylic acid, and the anhydrides of these acids, if available, e.g., maleic anhydride, fumaric anhydride and citraconic anhydride. In the terpolymer examples, butyl acrylate has been specifically disclosed, but other polymerizable acrylate monomers, as for example methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, methyl mehacryl ate, ethyl methacrylate, isobutyl methacrylate and 2-ethylhexyl methacrylate can be used. Other copolymerizable monomers which can be used include styrene and vinyl acetate. It should also be noted that terpolymers are described by way of example and not by way of limitation and copolymers can also be employed. Further copolymerizable monomers include derivatives of vinyl alcohol, e.g., aliphatic vinyl esters, the vinyl ester of Versatic acid, allyl esters of saturated monocarboxylic acids, aliphatic vinyl ethers, vinyl ketones, ethylenically unsaturated monocarboxylic and polycarboxylic, as well as the available anhydrides, nitriles, unsubstituted and substituted amides of said acids can be used. A more detailed list of monomers is found in U. S. patent 3,637,563, the relevant disclosure of which is incorporated herein by reference. The sulfonate surfactants enable the emulsion to remain stable over extended periods of time. The percent of vinylic acid which can be present without encountering a stablization problem increases with decreasing percent solids in the emulsion. Thus, while at 60% acid content and 40% solids coagulation occurs, decreasing either or both the acid content or solids levels, produces the desired coagulation free emulsion. The concentration of the surfactant in the system is not narrowly critical and generally, a surfactant concentration range from about 0.1 to about 10 percent by weight of total monomer concentration gives the desired result. Analytical Techniques a. Coagulum - Solids which were held in the 60 mesh screen are thoroughly washed, dried in a 1100 oven for two hours and weighed. When the amount of solid present is too small to collect, or if the coagulum is water soluble, a qualitative description is recorded. b. Mechanical Stability - The filtered latex is placed in an Osterizer blender, and blended for 10 minutes at maximum speed. If the latex coagulates during this time, mechanical stability is no good. c. Brookfield Viscosity - The filtered latex sample is poured into a 8 oz. sample bottle. The viscometer is fitted with the proper spindle, set for the proper rpm, and lowered into the latex. The viscosity is read directly from a dial. d. % Solids - Three weighing pans are tared, about 5 g. of the latex is placed in each, and the samples are placed in a 110-120 oven for 2 hours. The dried sample is then weighed, and % solids is calculated from (dry weight/wet weight) x 100. e. Surface tension is measured with a Fisher Tensiomat. f. pH is measured with any available pH meter. g. Turbidity - A sample of the latex is placed in a test tube and diluted with a 1% solution of sodium lauryl sulfate to given an absorbance reading of between 0.5 and 0.8 at 450 mm in a Spectronic 20 visible spectrometer. Absorbance readings are made at 450, 500, 550 and 600 mm. The slope of a best fit straight line for the relationship of log (absorbance) versus log (wavelength) is determined with a least squares computer program. This slope is recorded as turbidity. TABLE II BUTYL METHACRYLIC MECHANICAL BROOKFIELD % SURFACE SURFACTANT ACRYLATE STYRENE ACID COAGULUM STABILITY VISCOSITY SOLIDS TURBIDITY pH TENSION Igepal CO-630 - Sulfonate 50% 25% 25% V.Slight OK 29(1-60) 42.9 3.78 3.3 48.4 Igepal CO-630 - Sulfonate 30% 30% 40% 0.2% OK 7500(2-3) 50.2 3.03 3.2 68.0 Alfol 1012 & 3 E.O. Sulfonate 50% 25% 25% 1.9% OK 11(1-60) 39.6 1.77 2.6 42.0 Igepal CO-630 - Sulfonate 40% 0% 60% 100% - - - - - (Oxotridecyl & 4.2 E.O.) Sulfate 50% 25% 25% Foam** OK 120(1-30) 40.9 2.11 2.9 52.0 50% 25% 25% Foam* OK 104(1-30) 43.3 2.06 3.0 48.0 (Oxotridecyl & 4.2 E.O.) Sulfonate 50% 25% 25% Foam OK 25(1-60) 41.5 3.29 2.8 43.0 (Oxotridecyl & 4.2 E.O.) Sulfonate 50% 25% 25% Foam OK 32(1-60) 41.0 3.34 2.75 39.0 (Alfol 1012 & 3 E.O.) Sulfonate 50% 25% 25% 7.5 gn OK 20(1-60) 40.9 1.81 2.6 45.0 (Igepal 850) - Sulfonate 50% 25% 25% Foam OK 21(1-60) 42.9 3.53 2.75 53.0 50% 25% 25% Foam OK 26(1-60) 40.5 3.44 2.8 48.0 (Alfol 12 & 4 E.O.) Sulfonate 50% 25% 25% Foam OK 40(1-60) 41.2 2.91 2.75 43.0 (Alfol 12 & 4 E.O.) Sulfonate 50% 25% 25% V.Slight OK 44(1-60) 40.6 3.01 2.65 42.8 ** Complete Coagulation after 3 days * Coagulated in 24 hours

Claims: 1. An aqueous emulsion comprising the reaction product of a vinyl acid monomer and at least a second copolymerizable monomer, said vinyl acid monomer being present in an amount equal to about 5X to about 50X by weight based on total weight of said vinyl acid monomer and said at least a second copolymerizable monomer, said surfactant being present in an amount equal to about 0.1 to about 10 weight percent based on the total weight of said vinyl acid monomer and said at least a second copolymerizable monomer, said surfactant being represented by the formula: R1R2(CH2CH2O)n-1 CH2CH2SO3Me wherein: R1 is an alkyl or dialkyl having at least 6 carbon atoms; R2 Is hydrogen or an aryl group; n is at least 3; and Me is NH4, Na, Li and K. 2. The aqueous emulsion of Claim 1, wherein said at least a second monomer comprises from about 95X to about 50% of a monomer selected from the group consisting of acrylates, styrene or combinations thereof. 3. The aqueous emulsion of Claim I and/or 2, wherein R1 is alkyl from about 6 to about 18 carbon atoms or dialkyl having no greater than about 24 carbons, each alkyl group of said dialkyl having no greater than about 12 carbons. 4.The aqueous emulsion of Claim I to 3, wherein n is from about 6 to about 20. 5. The aqueous emulsion of Claim I to 4, wherein said vinylic monomer contains acrylic acid. 6. The method of producing a stable aqueous emulsion according to Claim I to 5 comprising the steps of contacting the monomers and the surfactant at an elevated temperature and to copolymerize the monomers. 7. The compound having the formula: EMI25.1 where in: R1 is an alkyl group having from 6 to 18 carbons; R2 is H or an alkyl group having from 6 to 12 carbons; n is greater than 9; and Me is a monovalent cation selected from the group consisting of NH4, Na, Li and K. 8. The compound of Claim 7, wherein R1 and H2 have a combined total of no greater than 24 carbon. 9. The compound of Claim 7 and/or a, wherein n is between about 15 and 30. lo. The method of producing aqueous polymer emulsions comprising: contacting a mixture of water, vinyl acetate monomer and at least about 0.1 percent by weight of vinyl acetate monomer of a surfactant having the formula: EMI25.2 wherein: R1 is an alkyl group having from 6 to 18 carbons; R2 is H or an alkyl group having from 6 to 12 car bons; n is greater than 9; and Me is a monovalent cation selected from the group consisting of NH4, Na, Li and K, the weight ratio of water to vinyl acetate being predetermined such that the resultant emulsion contains at least 40% by weight of solids. 11. The method of Claim 10, wherein R1 and R2 do not have a combined total of greater than 24 carbons. 12. The method of Claim 10 and/or II, wherein n is between about 15 and 30. 13. The method of Claim 10 to 12, wherein the surfactant is the sodium salt of nonyl phenoxy poly (ethyleneoxy) sulfonate and contains on the order of 20 ethylene oxide units. 14. A stable aqueous emulsion of a vinyl acetate polymer produced by polymerizing a monomer charge comprising: a. water; b. vinyl acetate monomer; and c. at least about 0.1 percent by weight based on the weight of the vinyl acetate monomer, of a surfactant having the formula: EMI26.1 R1 is an alkyl group having from 6 to 1 @ carbons; R2 is H or an alkyl group having from 6 to 12 carbons; n is greater than 9; and Me is a monovalent cation selected from the group consisting of NH4, Na, Li and K, said water comprising less than about 60Só by Freight of the emulsion. 15. The emulsion of Claim 1, wherein k1 and have a combined total of no greater than 24 carbons. 16. The emulsion of Claim 14 and/or 15, wherein n is between about 15 and 30. 17. The method of producing alkyl aryl poly (ethyleneoxy) ethyl sulfonates having at least 30 ethyleneoxy units, comprising the steps of a) contacting an alkyl phenoxy poly (ethyleneoxy) ethyl cloride with sodium bromide and contacting the resultant aikyl phenoxy poy (ethyleneoxy) bromide with Na2SO3 in sufficient quantity and at elevated temperature, for a time period sufficient to achieve sulfonation and separating the resultant alkyl aryl poly (ethyleneoxy) ethyl sulfonate or b) contacting an alkyl aryl poly (ethyleneoxy) ethyl chloride having at least thirty ethyleneoxy units with a molar excess of sodium sulfite, said excess being on the order of at least about 50%, maintaining an elevated temperature for a time period sufficient to achieve substantial conversion to the sulfonate. IS. The method of Claim 17, wherein the alkyl aryl poly (ethyleneoxy) ethyl sulfonate has the formula: EMI27.1 wherein: R1 is an alkyl group having from 6 to 18 carbons; R2 is H or an alkyl group having from 6 to 12 carbons; n is at least 30; and Me is a monovaient cation selected from the group consisting of NH4, Na, Li and K. 19. The method of Claim 17 and/or 18, wherein R1 and R2 have a. combined total of no greater than 24 carbons. 20. The method of Claim 17 to 19, wherein n is between about 15 and 30.

Inventors: CHAKRABARTI, PARITOSH M., KIRCHNER, DARRELL G.
Applicants: GAF CORPORATION
Application year: 1980
Main classification: C08F2
IPC codes: B01F17, C08F218, C08F2, C08F220, C08F18, C08G65