AU709352B2 - Surfactant blend of organosilicone and surfactants useful as agricultural adjuvants - Google Patents

Description

WO 97/23281 PCT/IB96/01408 SURFACTANT BLEND OF ORGANOSILICONE AND SURFACTANTS USEFUL AS AGRICULTURAL ADJUVANTS BACKGROUND OF THE INVENTION S Field of the Invention The present invention relates to organosiliconeisurfactant blends that are characterized by improved clarity. wetting and spreading properties.

Prior Art Nonionic surfactants are commonly used in agriculture as adjuvants to improve the efficacy of pesticides. micronutrients. biologicals. herbicides, fungicides. growth regulators and the like. Surfactants are important in the application, wetting, spreading and emulsifying either as part of the formulation or as part of a tank mix.

Nonionic surfactants are well known for their ability to reduce the surface tension of aqueous solutions. This reduction in surface tension is important for the spreading of solutions on difficult to wet surfaces such as the waxy surface of plant leaves.

Surfactants aid in uptake. Though conventional nonionic surfactants aid in wetting of spray formulations, they do not provide total wetting on hydrophobic leaf surfaces.

Organosilicone compounds have been found to be significantly useful as agricultural adjuvants because of their unique wetting properties. These surfactants give surface tension value significantly lower than conventional nonionic surfactants and can provide significant uptake of agricultural chemicals into the plant.

The spreading of aqueous solutions due to the organosilicone compounds gives total wetting as measured by low contact angle on leaf surfaces while conventional surfactants provide for less spreading as indicated by higher contact angles.

It has been reported that the organosilicone compound must be insoluble in water and dispersed in order to spread extensively. superspread. Organosilicone compounds that were soluble in water did not superspread. (Superspreading of Water- Silicone Surfactant on Hydrophobic Surfaces. S. Zhu et al.. Colloids Surfaces.

a:Physicochem. Eng. Aspects 90 (1994). 63-78) 1 WO 97/23281 PCT/IB96/01408 The interaction between surfactant pairs. while documented, is not consistent.

Some pairs demonstrate an ideal behavior where the pair provides the results that would be expected from the mixture whereas some pairs are non-ideal in providing surface tensions lower than that expected.

U.S. Pat. No. 3.562.786 describes solutions of nonionic organosilicone compounds blended with certain ranges of conventional nonionic and ionic surfactants.

The organosilicone compound is claimed to be useful in lowering the aqueous surface tension of organic surfactant solutions. The nonionic surfactants used in the patented combinations are primarily nonylphenol or alcohol ethoxylates. However, these materials when used with organosilicone compounds are known to interfere with the spreading characteristics of the organosilicone compounds.

U.S. Pat. No. 5.104.647 teaches the synergistic combination of organosilicone compounds with polyalkylene oxide block copolymers which forms dispersions allowing for good surface tension reduction without sacrificing the spreading efficacy of the mixture. Nonylphenol or alcohol ethoxvlates interfere with the spreading characteristics of the organosilicone compounds since they do not form dispersions. While the 5.104.647 patent teaches that the weight fraction of organosilicone compound to polyalkylene oxide block copolymer can range from 1% to 99% and conversely the copolymer from 99% to the preferred ranges are from 1% to 50% and 50% to 1%.

These later ranges correspond with the ranges taught in the 3.562.786 patent where the weight ratio between the organosilicone compound and the surfactant ranges from 0.001 to 1 to 1/1. In both these instances, the prior art is taught to use less organosilicone compound than surfactant in order to obtain the desired results. No superspreading or lowering of the contact angle was taught.

Applicants have unexpectedly found that these limitations on the superspreading can be overcome. Clear solutions having higher concentrations of organosilicone compound which show lower dynamic surface tension and increased spreading can be obtained over that expected from the two ingredients. The surfactant mixture of this 3 invention provides an improved dynamic and equilibrium surface tension values when compared to the individual components of the mixture.

Summary of the Invention A first aspect of the present invention provides a surfactant blend providing improved superspreading characteristics comprising: a) from about 60% to about 95% of an organosilicone compound(s) which can be represented by the general formula: MDyD'xM Formula I wherein M represents Me3SiO/; D represents Me 2 SiO;D' represents MeRSiO; Me equals

CH

3 R equals CnH2nO(C 2

H

4 0) 3

(C

3 HO6)bR'; and R' can each be the same or different on any given molecule and can be hydrogen, an alkyl group having 1 to 4 carbon atoms, or an alkyl ester group wherein the alkyl group of the ester has 1 to 4 carbon atoms: wherein x ranges from about 1 to 5; y ranges from about 0 to 5; n ranges from about 2 to 4; a ranges from about 3 to 25: and b ranges from about 0 to 25: the oxyalkylene groups being is random and/or block mixtures of oxyalkylene units: and b) from about 30% to about 5% of non-silicone containing surfactants(s) wherein the hydrophobic group or groups of the surfactant each independently comprises an aliphatic moiety having from about 4 to about 12 carbon atoms.

This surfactant blend provides clear aqueous solutions with low surface tension without sacrificing the spreading efficacy of the mixture. The surfactant blend is especially useful in agricultural applications as an adjuvant for the delivery of agriculturally active ingredients such as fertilizers, micronutrients, biologicals, and pesticides such as herbicides, fungicides insecticides and growth regulators, to treatment sites.

25 A second aspect of the present invention provides a process for treating a hydrophobic surface with an aqueous treatment composition wherein the surface resists spreading of aqueous treatment solutions which comprises forming an aqueous treatment compositions with an amount of the composition of the first aspect of the invention defined above effective to improve spreading of the treatment composition and applying the so made treatment composition to the hydrophobic surface to be treated.

Detailed Description of the Drawings Figure 1 is a graphic representation of the data of Example 1 illustrating the degree on non-ideal behaviour observed with a mixture of BOS and SILWET L-77.

i i [R:\LIBFF]04939.do:mcc 3a Figure 2 is a graphic representation of the data of Example 1 illustrating the synergism in reduction of dynamic surface tension observed with mixtures of SILWET L-77 and BOS.

Figure 3 is a graphic representation of the data of Example 2 illustrating the synergism in reduction of dynamic surface tension observed with mixtures of SILWET L-77 and MPOB Na sulfate.

Figure 4 is a graphic representation of the data of Example 2 illustrating the synergism in reduction of dynamic surface tension observed with mixtures of SILWET L-77 and MBOP Na phosphate.

Ic Figure 5 is a graphic representation of the data of Example 3 illustrating the degree of non-ideal behaviour observed with mixtures of SILWET L-77 and DA-530.

9 9 9 [R:\LIBFF]04939.doc:mcc WO 97/23281 PCT/IB96/01408 Figure 6 is a graphic representation of the data of Example 4 illustrating the synergism in dynamic surface tension verses bubble surface age for SILWET L-77. DSB and their mixtures.

DETAILED DESCRIPTION OF THE INVENTION The organosilicone compound(s) which can be used in the present invention can be represented by the general formula: MDvD cxM Formula I wherein M represents Me 3 SiO (represents Me 3 SiO or MeSi as necessary to form a chemically complete structure): D represents MeSiO: D' represents MeRSiO: Me equals CH,: R equals CnH,_O(C H 4 0),(C.H 6 0)hR': y ranges from about 0 to 5. preferably zero: x ranges from about 1 to 5. preferably 1: n ranges from about 2 to 4. preferably 3: a ranges from about 3 to 25. preferably 3 to 15: and b ranges from about 0 to 25. preferably 0 to it being understood that the oxyalkylene groups may be random and/or block mixtures: and R' can be hydrogen, an alkyl group having 1 to 4 carbon atoms, or an alkyl ester group wherein the alkyl group of the ester has 1 to 4 carbon atoms. Each R' can be same or different on any given molecule. Preferably. R' is hydrogen or a methyl group.

These organosilicone compounds can be represented by the following examples: (Me 3 SiO),Si(Me)CHCH, CH2(OCH, CH,) 8

OH

(Me 3 SiO),Si(Me)CH,CH, CH 2 (OCH, CH) 8 OAc Me 3 SiOSi(Me) 2 OSi(Me), OSi(Me), CH 2

CH

2 CH,(OCH, CH,)gOH (Me 3 SiO)Si(Me) CHCH 2 CH,(OCH, CH,) 7 5 OMe The most preferred organosilicone compound is represented by the following formula: (MeSiO) 2 Si(Me) CHCH, CH,(OCH 2

CH),

7 .OMe Formula II also known as SILWET L-77.

WO 97/23281 PCT/IB96/01408 The organosilicone compounds useful in the invention can be prepared by several conventional methods such as by a process that involves forming a mixture of a siloxane polymer containing a silicon-bonded, halogen-substituted monovalent hydrocarbon group and an alkali metal salt of an oxyalkylene polymer and heating the mixture to a temperature sufficiently elevated to cause the siloxane polymer and the salt to react to produce the desired compound. Some of these compounds can be made by hydrosilation of allvl compounds.

The water-soluble surfactants or surface active agents which provide the useful and unexpected benefits of the compositions of the invention are generally characterized structurally as having an elongated non-polar hydrophobic portion comprising from about a

C

4 to about C, 2 aliphatic moiety and a short polar hydrophilic portion. These surfactants can be classified as synthetic, silicone-free. short chain, anionic. non-ionic and/or amphoteric.

If the elongated non-polar portion of the molecule includes an anion in the aqueous solution, the surfactant is termed anionic. Anionic surfactants include sulfates, phosphates.

sulfonates. carboxylates and taurates. In the anionic class, the most commercially important anion groups are carboxy (-COOH). sulfonic acid and sulfuric ester (-OSO 3

H).

The anionic surfactants used herein include alkyl and alkyl ether sulfates and suffonates. alkvlaryl and alkylaryl ether sulfates and sulfonates. alcohol ether sulfates. ether carboxylic acids and salts thereof, c-olefin sulfonate salts, alkyl (mono or di) sulfosuccinates. monoalkvl ether sulfosuccinates. alkyl sarcosinates. alkvl monoglyceride sulfate and sulfonates. acyl isethionates. acyl methyl taurates. salts of fatty acid and fatty acid esters, and alkyl. alkylaryl. ethoxylate mono or di phosphate esters salts, fatty alcohol ether phosphate ester salts, condensates of fatty acids and amino acids, and mixtures thereof. These surfactants can be used in admixture.

As used in this listing, alkyl is intended to mean an aliphatic straight, branched or cyclic C 4

-C,

1 carbon chain such as butyl. caprxl. capornl. capryryl. alkylaryl is intended to mean alkvl as defined before and aryl is intended to cover benzene, naphthalene, such as WO 97/23281 PCT/IB96/01408 nonylphenyl and dibutylnaphthyl and substituted derivatives thereof such as nonylphenol diphenyl oxide, alcohol is intended to be coextensive with the definition for alkvl. olefin is intended to cover an unsaturated carbon chain of 4 to 12 carbons, acyl and fatty acid are intended to have a carbon chain of from 4 to 12 carbons, and ether or ethoxylate is intended to cover EO and/or PO of from 1 to 5. preferably from I to 4. The surfactant can also have a counterion which can be alkali metal of sodium or potassium, ammonium or mono. di or tri-ethanol amine.

These surfactants can be illustrated by ammonium or sodium 2-ethylhexvl sulfate or sulfonate. sodium octyl sulfate. ammonium nonylphenyl ether sulfate (2 EO) disodium Noctyl sulfosuccinate: dibutvl naphthalene sodium sulfonate. sodium mono or di dodecvl diphenyl oxide disulfonate. sodium decvl naphthalene sulfonate sodium octyl N-methyl taurates. disodium dioctyl sulfosuccinate. sodium decyl isethionate. sodium nonvl isethionate. 2-ethylhenanol phosphate. mono and di phosphate esters of nonylphenol ethoxylates (2 EO) sodium butoxy ethyl acetate and the like.

Non-ionic surfactants do not dissociate in water but nevertheless are characterized by a relatively polar portion and a relatively non-polar portion.

The nonionic surfactants used herein include fatty acid glycerine esters, sorbitan fatty acid esters, sucrose fatty acid esters, and polyglycerine fatty acid esters wherein the fatty acid has from 4 to 10 carbon atoms.. higher alcohol ethylene oxide adducts. single long chain polyoxyethylene alkvl ethers. alkyl and alkylaryl ethoxylates. polyoxyethylene alkvl allyl ethers, polyoxyethylene fatty acid esters, polyoxyethylene glycerine fatty acid esters, polyoxyethylene propylene glycol fatty acid esters, polyoxyethylene sorbitol fatty acid esters, and polyoxyethylene fatty acid amides wherein the fatty acid has from 4 to carbon atoms. polyoxyethylene alkvl amines, an alkylpyrrolidone. glucamides.

alkylpolyglucosides. mono- and dialkanol amides. a polyoxyethylene alcohol mono- or diamides and alkvlamine oxides wherein the aliphatic group ranges from 4 to 10 carbon atoms.

6 WO 97/23281 PCT/IB96/01408 Amphoteric surfactants form zwitterions in water so that the same molecule can act as either an anionic or a cationic surfactant. The amphoteric surfactants used herein include amino acid. betaine. sultaine. phosphobetaines. imidazoline type amphoteric surfactants.

Amphoteric surfactants useful in the invention can be illustrated by disodium caporylo or caprylo or capryrylo beta-aminodipropionate. C 4

-C

8 N-alkyl betaaminopropionic acid and the sodium salt thereof. sodium octyl amphocarboxylate. sodium caporylo or caprvlo or capryrylo amphoacetate: disodium caporylo or capryvo or capryrvlo amphodiacetate. sodium caprvloampho hydroxypropyl sulfonate. sodium capryryl hydroxyproryl sulfonate. capryl amidoamine carboxylate. sodium mixed C 8 amphocarboxylates. and mixtures thereof. By amphocarboxylate is meant to include

RC(O)NHCH,CH

2

N(RI)CH

2 CH0OH where R represents a fatty alkvl group of 4 to carbons. and R, is an alkylcarboxy group of 2 to 3 carbon atoms in the alkvl group.

Also useful herein are gemini surfactants. which is a term used herein to identify surfactants having two or three hydrophobic groups with a linkage between hydrocarbon chains and two or more hydrophilic groups attached to hydrophobic portions in the molecule. The hydrophilic and hydrophobic groups can be the same on either side of the linkage or different. A Gemini surfactant can be anionic. non-ionic. or amphoteric.

A particularly preferred group of gemini surfactants includes compounds of the formula:

R,

R O(EO)a(PO)b-R 2 I. R3 Rt (F.OE(POL-R, 8 wherein R independently represents alkyl of from about 4 to about 20 carbon atoms. R 1 independently represents hydrogen and alkyl of from about 4 to 20 carbon atoms: R 2 independently represents hydrogen.

-SO

3 M, -OP(O)(OM) 2 -CH2COOM,

CH

2

CHOHCH

2

SO

3 M, wherein M is hydrogen, alkali metal such as sodium, potassium, alkaline earth metal such as magnesium and calcium, ammonium or organic base salt: and

R

3 represents alkylene of from one to about 10 carbon preferably from about 1 to about 4 atoms or wherein R 4 represents alkylene of from 1 to about 10 carbon atoms and aryl, e.g. phenylene,

R

3 also represents -0-Rs-O- wherein R 5 represents aliphatic or aromatic moieties of from 1 to about 10 carbon atoms with the proviso that when R 3 is alkylene, then R 2 is not hydrogen. EO represents ethyleneoxy radicals. PO represents propyleneoxy radicals, a and b are numbers of from 0 to about 100: a is preferably from about 0 to about 30 and b is preferably from about 0 to 10. When R 2 is hydrogen, b is not zero and when R 2 is other than hydrogen, b is preferably zero.

Preferably, R 3 is alkylene and more preferably CH 2 These compounds are more fully is disclosed and claimed in the copending application of Tracey et al. owned by the assignee of granted US patent 5,710,121 filed on the same day as the present application, the entire disclosure of which is incorporated herein by reference.

Illustrative examples of water-soluble gemini surfactants useful in the compositions of the present invention include disodium methylene bis-(octyl phenol sulfate), disodium methylene bis-(octyl phosphate), disodium methylene bis-(octyl phenol ethoxy ether sulfate), disodium methylene bis-(octyl phenol ethoxy ether phosphate).

As used herein the terms "alkyl" or "alkylene" include straight as well as branched chains.

It should be noted that mixtures of the desired organic surfactants can also be used 25 in compositions of the present invention in order to achieve desired performance.

Compositions of the invention can also include other surfactants, or additives normal to the industry including active components used as biocides, pesticides and the like with the qualification that the amount of these additional components is insufficient to [R:\LIBFF]04939.doc: mcc WO 97/23281 PCT/IB96/01408 totally negate the superspreading or other surfactant enhancing characteristics of the compositions of the invention. Such auxiliary additives may be suitably chosen for a desired composition and generally include inorganic salts such as Glauber salt and common salt. builders. humectants. solubilizing agents. LUV absorbers. softeners. chelating agents.

S and viscosity modifiers.

The organosilicone compound in the blend of organosilicone compound and the desired surfactants of the invention is used in amounts ranging from about 70% to about preferably from about 80% to about 95%. and more preferably from about 85% to about 95% by weight based on the actives weight. Correspondingly. the other surfactants of the invention are used in amounts ranging from about 30% to about preferably from about 20% to 5% and more preferably from about 15% to about 5% by weight actives.

The mixtures of organosilicone and conventional surfactants as disclosed in the invention provide low surface tension and good dynamic surface tension properties, allowing coating formulations to rapidly attain low equilibrium surface tensions. The compositions of the invention can be used in treating a surface which rests the spreading of an aqueous treatment solution by applying to the surface in amount effective to improve the spreading of the treatment solution. These mixtures are effective wetting, spreading.

leveling and flow control agents for various coating applications. especially in water-based systems. particularly for water-based coating processes designed for difficult to coat. low surface energy substrates.

The surfactant blends of the present invention find particular utility as superspreading additives for paints and coatings. adhesives and adhesive controlled release agents. hard surface cleaners and particularly as adjuvants for dispersing, wetting and spreading agriculturally active ingredient-containing solutions such as micronutrients.

fertilizers. biologicals. and pesticides such as herbicides. fungicides. insecticides. growth regulators. and the like and mixtures thereof.

In controlling pests. weeds using both selective and nonselective herbicides or insects using insecticides, foliage or fruit applications from aqueous solutions have been WO 97/23281 PCT/IB96/01408 found to be the most effective means for application. Success of foliage sprays depends on a number of factors. particularly the nature of the solution and the type of leaf or fruit surfaces involved.

Many plants possess a moisture proof waxy coating (cuticle) on the leaves or fruit which prevents excessive loss of water and is relatively impervious to water nor does water readily penetrate the plant surface.

Plant surfaces are uneven. being ridged or composed of hemispherical cell walls.- Water droplets assume spherical shapes with minimum contact surfaces. If the plant part is in a vertical position or if the spray droplet has considerable momentum as it strikes the plant. an aqueous spray solution may bounce or run off to a large extent.

In many sprays. the bulk of the volume is made up of water because it lends driving force to the spray solution. Because of the chemical and physical makeup of the plant surface. aqueous sprays are repelled by most plant surfaces: they round up into spherical droplets and tend to run off. Even when atomized by high pressure and applied with great force. they do not stick to the waxy surfaces of many plants. If they do stick. they stay in place or collect into droplets and present a minimum surface of contact.

The surfactant blends of the present invention can improve the spreading characteristics of the spray solution. enhance dynamic and equilibrium surface tension values and assist in dispersing the pesticides.

The present invention is further illustrated in the Example(s) which follow which are intended to illustrate and do not limit the invention. All parts are by weight. all percentages of surfactants/organosilicone compound are by weight based on the actives weight thereof and all temperatures are in degrees C. in the Examples. Specification and appended claims unless set forth otherwise.

EXAMPLE 1 WO 97/23281 PCT/IB96/01408 This example demonstrates that a surfactant blend of the compound of Formula II (SILWET L-77) and sodium 2-ethylhexyl sulfate (RHODAPON BOS) displays strong nonideal solution behavior.

The blends for the Examples were prepared by simple admixture.

The performance of the surfactant mixtures set forth in this invention was evaluated by several methods. Surfactant interactions were determined by equilibrium surface tension measurements by the Wilhelmy Plate Method using a Krtiss K-12 Tensiometer at 25 0 C and dynamic surface tension measurements by the Maximum Bubble Pressure Method (MBPM) using a KriAss BP-2 Dynamic Surface Tensiometer at constant room temperature 1o (22 0

C).

The degree of interaction for the surfactant mixtures is expressed as the difference between the expected and the observed values for surface tension. Synergy is defined as a reduction in surface tension below that of either individual surfactant. Non-ideal mixing is defined as a reduction in surface tension below that expected value for a linear relationship between two surfactant components.

The effect of surfactant mixtures on spreading was evaluated by determining the spread ratio of an aqueous solution on a hydrophobic surface. A smooth Parafilm surface was prepared by a) dipping a clean glass slide into a hot Parafilm solution in cyclohexane: b) evaporating the solvent in an oven at 60'C for one hour: c) cooling the slide covered by Parafilm down to room temperature (22 0 C) for 30 minutes before using. 8 pl (0.008 gram) of a surfactant solution was applied to the smooth Parafilm surface. The spread area was recorded at 60 seconds. The spread ratio was calculated by dividing the spread area of 8 pl of distilled water into the spread area obtained using the same volume of surfactant solution.

The surfactant solutions were freshly prepared before each evaluation using deionized water.

The dynamic surface tension of surfactant mixtures was determined by the MBPM described earlier in this text. Figure 1 illustrates the degree of non-ideal behavior observed WO 97/23281 PCT/IB96/01408 with a mixture of BOS and SILWET L-77. Although the expected interaction profile for these non-ionic-anionic mixture is linear, the observed behavior is non-ideal in nature.

Similar interactions are observed with other anionic surfactants such as sodium octvl sulfate (RHODAPON OLS) and 2-ethylhexanol phosphate (RHODAFAC PEH).

Data on surface tension, contact angle and spreading ratio on the surface of a Parafilm using BOS and SILWET L-77 are listed in Table 1. It is seen that addition of to 20% of BOS to SILWET L-77 not only improved the clarity of the solution but also improved the spreading properties.

Table I Surface and Spreading Properties of SILWET L-77/RHODAPON BOS Mixtures (pH 6.7. T 220C) Sample SILWET Rhodapon L-77/ L-77/ L-77/ L-77/ L-77/ L-77 BOS BOS BOS BOS BOS BOS total con. 0.1 0.1 0.1 0.1 0.1 0.6 1.1 ratio 9/1 8/2 7/3 1/5 1/10 appearance hazy clear cloudy' cloudy cloudy clear clear S.T. 20.8 45.6 20.2 20.5 20.6 20.6 21.5 dvne/cm *contact -5 -90 -3 -3 ~3 -3 angle(°) 17.5 1 25 20 18 16 0.008 gram of surfactant solution on the Parafilm surface.

R. spreading factor spreading area of 0.008 gram of surfactant solution on Parafilm surface after 1 minute/spreading area of 0.008 gram of DIW on Parafilm surface after 1 minute Data on dynamic surface tension of SILWET L-77/RHODAPON. BOS and their mixtures are shown in Table 2.

WO 97/23281 PCT/IB96/01408 Sam L-77

BOS

BOS(

BOS

L-77/] 0.1% L-77/ 0.6%( L-77/ 1.1%.

Table 2 Dynamic Surface Tension of SILWET L-77/RHODAPON BOS Mixtures (pH 6.7. T 22 0

C

ple Dynamic Surface Tension (dyne/cm) at Different Bubble Surface Age 0.10 sec. 0.12 5 sec. 0.20 sec. 0.25 sec. 0.5 sec. 1.0 sec.

0.1% 57.0 53.8 47.5 44.5 30.5 28.0 0.1% 69.0 68.5 68.2 68.0 67.8 67.0 68.0 67.0 66.0 65.5 64.5 63.0 1.0% 57.5 56.5 55.0 54.5 53.3 50.0 BOS 57.5 5 4.5 49.0 46.0 375 (9/1) 30S 1/5)1 30S 1/10 51.5 48.5 47.0 44.0 4' .0 38.6 40.2 28.0 26.0 36.0 26.0 25.0 Figure 2 shows the synergism in reduction of dynamic surface tension. The mixtures of L-77/BOS showed lower dynamic surface tension values than that of either individual component. This indicates that the L-77/BOS complexes diffuse from the aqueous solution to the air/water interface much faster than either L-77 or BOS individually. The faster spreading property of the mixture may be partially attributed to the synergism in the reduction in dynamic surface tension.

WO 97/23281 WO 9723281PCT/IB96/01408 EXAMPLE 2 It has been found that the mixtures of SILWVET L-77 and MBOP Na Sulfate [sodium methylene bis-(oct-vl phenol sulfate)] and the corresponding phosphate Gemini surfactants demonstrated excellent superspreading properties and synergistic interactions in S surface tension reduction as well as in dynamic surface tension reduction. The MBOP is a known compound that was disulfated using a sulfur trioxide pyridine complex method and phosphated by standard methods. The data on spreading factor. surface tension. dynamic surface tension, and contact angle on the Parafilm surface are listed in Table Table 3 0 Surface and Spreadin' Properties of SILWET L-77/MBOP Sulfate Mixtures 1 /wt.. oH 6.7. T 22 0

CI

1PRIVATE Silwet 1 MBOP L-77/ L-77/ L-77/ }Sample L-77 Slae MBOP MBOP MBQP Slae Sulfate Sulfate Sulfate (8/2) appearance haz-v clear clear clear clear S.T. 20.8 2 9.5 20320.5 21.0 I (dyne.,cm)

I

*contact -3 5 -3 -5 angle(') _151 L- 1*7.5151753 WO 97/23281 WO 9723281PCT/IB96/01408 Table 4 Surface and Spreading Pronerties of SILWET L-77/MIROP Phosnhate Mixtures 12H 6.7. T 22 0 0) Sample SIL WET M-BOP L-77/ L-77/ L-77/ L.7 Phosphate MBOP MBOP MEOP (8/2) appearance hazy Tinsoluble clear clear clear S.T. 2)0.8 N/P 20.2 20.5 21.0 (dvne/cm)IIII contact -sN/P anizle( 0 R 17.5 N/P 18 16 Table Dynamic Surface Tension of SILWET L-77/MBOP Sulfate and SILWET L77/iMBOP Phosphate Mixtures pH T 22 0 0~ Sample Dynamic Surface Tension (dyne/cm) [PRIVATE)} 0. 10 sec. i0. 12 5 sec. 0.20 sec. T0.25 sec. 1 0.5 sec.

SIL WET 57 53.8 47.5 44.5 .30.5 L-77 MBOP sulf. 68.8 j 67.8 67.0 I 66.8 65.5 MBQP phos. N/P N/P N/P N/PD N/P L-77/sui fate 51.0 47.0 45.0 40.4 27.2 L-77/sulfate 50.0 j 46.0 38.5 35.5 28.8 L-77/phos. 52 46.8 40.0 36.8 27.0 (9/1) WO 97/23281 PCT/IB96/01408 Plots of dynamic surface tension vs. bubble surface age for L-77/MBOP sulfate and L-77/MBOP phosphate mixtures are shown in Figures 3 and 4. respectively.

From Tables 3 and 4. it is observed that addition of 10% of MBOP sulfate (or phosphate) to SILWET L-77 solution not only improved the clarity of the solution, but also improved the superspreading property. Moreover, the mixtures of L-77-MBOP sulfate (or phosphate) produced the same or even lower contact angle on the Parafilm surface and larger spreading area than SILWET L-77 alone. In addition. It is seen that addition of 10% to 20% of MBOP sulfate (or Phosphate) decreased the surface tension by 0.7 -0.3 dyne/cm compared with 0.1% of SILWET L-77 solution. This is an indication of synergistic interactions between L-77 and MBOP sulfate (or phosphate) surfactants.

From Table 5 and Figures 3 and 4. it is apparent that mixtures of SILWET L- 77/MBOP sulfate (or phosphate) showed much lower dynamic surface tension values than that of either individual component above. This indicates that the SILWET L-77/MBOP complexes diffuse from the aqueous solution to the air/water interface much faster than either SILWET L-77 or MBOP surfactant alone.

EXAMPLE 3 A mixture of SILWET L-77 and a non-ionic surfactant branched chain isodecvl alcohol ethoxylate with 4 EO groups (RHODASURF DA-530) also showed good spreading property and non-ideal behavior in surface tension reduction. Figure 5 illustrates the degree of non-ideal behavior observed with mixtures of DA-530 and SILWET L-77. Although the expected interaction profile for these non-ionic surfactants is linear, the observed behavior is non-ideal in nature. Data on contact angle and spreading ratio of these mixtures on the Parafilm surface are listed in Table 6.

WO 97/23281 PCTIIB96/01408 Table 6 Spreading Properties of L-77-RHODASURF DA-530 Mixtures T 22 0 It is seen that the L-77-DA-530 mixtures containing 10-20% of DA-530 showed basically the same spreading properties as SILWET L-77 alone.

EXAMPLE 4 Mixtures of SILWET L-77 and disodium dodecyl diphenyl oxide. disulfonate (RHODACAL DSB) demonstrated non-ideal behavior in surface tension reduction and synergistic interaction in dynamic surface tension reduction. Data on surface tension and spreading ratio on Parafilm surface are listed in Table 7.

Table 7 Surface and Spreading Properties of L-77/DSB Mixtures T It is seen that mixed solutions of L-77 and DSB had better clarity and showed nonideal behavior in surface tension reduction. They basically remained the same spreading performance as Silwet L-77. Data on dynamic surface tension are listed in Table 8. Plots WO 97/23281 PT19/10 PCT/IB96/01408 of dvnamic surface tension vs. bubble surface age for SILWETT L-77. DSB. and their mixtures are shown in Figure 6.

Table 8 Dynamic Surface Tension of L-77fDSB Mixtures 1 T 22'C) (PRI VAT Dvnamic Surface Tension at Different Surface Age, dyneicm E (PRIVAT 0.l1sec. 0.l125sec. O.20sec. 0.25sec. 0.5sec. l.Osec.

L-77 i7.0 53.8 47.5 44. 5 30.5 28 DSB 69.8 69.2 68.8 68.5 68.0 67.2 L-77/DSB 54.5 51.2 44.6 41.8 30.0 27.6 L-77/DSB 52.6 49041.8 38.8 28.5 2.

1 1 It is clear that dynamic surface tension of the mixed solutions are lower that that of either individual component. This indicates the synergistic interaction between these two surfactants.

EXAMPLE Mixtures of SIL WET L-77 and C8-amphocarboxvlate (MIRANOL JEM Conc.) demonstrated non-ideal behavior in surface tension reduction and synergistic interaction in dynamic surface tension reduction. Data on surface tension and spreading ratio on Parafilm surface are listed in Table 9.

WO 97/23281 WO 9723281PCTIIB96/01408 Table 9 InflP~TI Snreadin~ Pronerties of L-771.WM Mixtnre~ Surfacp and Snreading Properties of L-77/.TFM Mixture-q T 25*0 Sample SIL WET MIRANOL L-77/JEM L-77/JEM L-77 JEM Conc. (8:2) appearance hazv clear cloudy slightly cloudy surface tension 20.8 27.0 20.5 20.7 (dyne/cm) R 17.5 1 1 1 22 1 It is seen that mixed solutions of L-77 and MIRANOL JEM Conc. showed nondeal behavior in surface tension reduction and etrsraigpromneta I E L-77 at the same concentration.

EXAMPLE 6 Mixtures of SIL)WET L-77 MBOP sulfate and RHODAPON BOS (0.005%w.t.) demonstrated not only good clarity, but also synergistic interaction in dynamic surface tension reduction and showed much better spreading performance than SIL WET L-77 alone. Data on surface tension and spreading ratio on Parafilm surface are listed in Table 10. Data on dvnamic surface tension of the mixture are listed in Table 11.

Table Surface and Spreading Properties of L-77/MBOP Sulfafte/BOS Mixtures T Sample SIL WET L-77 Rhodapon BOS MBOP sulfate 77/BOS/MBOP (910.5/0.5) appearance hazy, clear clear clear surface tension 20.8 45.6 29.5 20.6 (dyne/cm) R 17.5 1 1.5 WO 97/23281 WO 9723281PCTIIB96/01408 It is seen that mixed solutions of SIL WET L-77. BOS and MBOP sulfate showed non-ideal behavior in surface tension reduction and much better spreading performance that SIL WET L-77 alone at the same concentration.

Dynamic Surface Tension of L-771BOS/MBOP Sulfate Myixtures T 22'C) Sample Dynamic Surface Tension at Different Surface Age. dyne/cm 0.l1sec. .l25sec. 0.20sec. 0.25sec. 0.5sec. I.Osec.

L-77 57.0 53.8 47.5 44.5 28.0 MBOP 68.8 67.8 67.0 66.8 65.5 63.0 BOS 69.0 68.5 68.2 68.0 67.8 67.0 L-77/B30S 53.0 49041.5 .38.0 28.0 f 27.0 /MBOP From Table 11, it is apparent that mixtures of SIL WET L-77/MBOP Sulfate/BOS showed much lower dynamic surface tension values than that of either individual component.

Claims (7)

18. A process as recited in claim 17 wherein said aqueous treating composition is selected from the group consisting of paints, coatings, adhesives, control release agents, and agricultural adjuvants.

19. A process for applying an agriculturally active composition to a plant surface which comprises forming an aqueous solution of an agriculturally active composition with the composition of claim 1 and applying the so made solution to the plant surface. A process for applying pesticides to a plant surface which comprises forming an aqueous solution of pesticide with the composition of claim 1 and applying the so made solution to the plant surface.

21. A process for cleaning hard surfaces which comprises contacting the hard surface with a cleaning composition comprising the composition of claim 1.

22. A process as recited in claim 17, wherein y is zero, x is 1 and ranges from about 3 to about

23. A process as recited in claim 19, wherein y is zero, x is I and ranges from about 3 to about

24. A surfactant blend providing improved superspreading characteristics, substantially as hereinbefore described with reference to any one of the Examples. A process for treating a hydrophobic surface with an aqueous treatment composition wherein the surface resists spreading of aqueous treatment solutions, substantially as hereinbefore described with reference to any one of the Examples.

26. A hydrophobic surface when treated with an aqueous treatment composition S. "according to the process of any one of claims 17-18, 22 or :Dated 2 July, 1999 "Rhone-Poulenc Surfactants and Specialities, L.P. 2 5 Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON e:\IBFF04939.oc:mcc [R:\LIBFF]04939.doc:mcc