TETRACHLOROISOPHTHALONITRILE DISPERSION

Abstract: Finely divided tetrachloroisophthalonitrile powder is dispersed in a vehicle which is a mixture of calcium alkyl aryle sulfonate, nonionic surfactant, fatty acid or other ester, coupling agent and optionally lecithin. The vehicle provides a water and organic solvent compatible tetrachloroisophthalonitrile dispersion having a pourable and pumpable viscosity as well as settling resistance which is useful as an antimicrobial agent in both water-based and solvent-based protective coatings such as paints.

Description: TETRACHLOROISOPHTHALONITRILE DISPERSION BACKGROUND OF THE INVENTION 1 * Field of the Invention This invention relates to a dispersion of an antimicrobial agent for use in water-based and solvent-based protective coatings such as paints. 2. Description of the Prior Art Antimicrobial agents such as 2,Ψ,5,6-tetrachloroisophthaJonitrile are used in water-based and solvent-based protective coatings such as paints. These agents are almost insoluble in water and are sparingly soluble in organic solvents. For example, 2, ,5,6-tetrachloroisophthalonitrile is soluble to the extent of about 0.6 ppm in water at 25°C and is soluble at 25°C in xylene 8% (wt/wt), cyciohexane 3%, acetone 2% and kerosene at less than 1%. Since solutions of this agent are too dilute for most purposes, concentrated formulations are prepared using the solid agent in the form of finely divided powder. Convention¬ ally, this agent is formulated as wettable powders and aqueous suspensions for use in aqueous systems in agriculture. U.S. Patent 3,948,636 - Marks, issued April 6, 1976, describes preparation of fiowable aqueous compositions of water-insoluble pesticides such as tetrachloroisophthalonitrile. These fiowable aqueous compositions are for use in aqueous systems in agriculture. Because of insolubility of tetrachloroisophthalonitrile and difficulties involved in its formulation, in protective coatings, improved methods fo incorporating this agent in protective coatings are required. Further, ne governmental regulations impose additional restrictions on the handling, formu lating and use of the solid form of this biocidal agent so there is a need fo dispersible formulations which can be directly added to protective coatings. /00654 - 2 - SUMMARY OF THE INVENTION A tetrachloroisophthalonitrile dispersion is prepared by dispers finely divided tetrachloroisophthalonitrile powder in a vehicle which is a mixt of calcium alkyl aryl suifonate, nonionic surfactant, ester, coupling agent optionally lecithin. The vehicle provides a water and organic solvent compati dispersion having pourable and pumpable viscosities as well as settling resistan The resulting dispersion is an antimicrobial agent for use in both water-based solvent-based protective coating such as paints. DESCRIPTION OF THE PREFERRED EMBODIMENTS Useful tetrachloroisophthalonitrile dispersions may contain the ran of indicated and preferred ingredients shown below: Indicated Preferred parts by weight parts by weight tetrachloroisophthalonitrile 10 - 70 0 - 60 calcium alkyl aryl suifonate 5 - 50 25 - 30 nonionic surfactant 5 - 50 15 - 20 ester 5 - 50 20 - 30 coupling agent 5 - 50 10 - 20 lecithin 0 - 10 2 - 5 The tetrachloroisophthalonitrile is 2,4,5,6-tetrachloroisophth nitrile, also known as 2, ,5,6-tetrachloro-l,3-benzenedicarbonitrile or 1 dicyano-2,4,5,6-tetrachIorobenzene. It is available under the registered tr names of Nopcocide ® N-96, Daconil ® 2787, Termil ® and Forturf ® . It the structural formula: and forms colorless crystals which melt at 250° to 251 °C. This tetrachloro¬ isophthalonitrile is a broad spectrum foliage and fruit protectant fungicide as well as an industrial antimicrobial agent. It may be prepared by the process described in U.S. Patent 3,290,353 - Battershell and Bluestone, December 6, 1966, wherein halogenated aromatic nitriles are prepared from the corresponding ring-chlorinated acid chlorides. The acid chloride is converted to the corresponding amide by dissolving the_acid chloride in a suitable organic solvent and introducing ammonia to form the amide. Either anhydrous or aqueous ammonia is employed. The ring-chlorinated aromatic amide is dried and then reacted with a dehydrating agent such as phosphorus pentoxide or phosphorus oxychioride to obtain the nitrile. Details on its preparation and properties- are given in U.S. Patent 3,331,745 - Battershell and Bluestone, July 18, 1967. The calcium alkyl aryl suifonate used in the vehicle may be Witco Chemical Corp. Emcol ® D-24-25 (25% ethanol) or Witconate® 605-T (25% xylene type solvent), calcium dodecyl benzene suifonate, alkaline earth petro¬ leum sulfonates and lead alkyl aryl sulfonates. The alkyl aryl sulfonates may have from 6 to 18 carbon atom alkyl groups. Useful nonionic surfactants for the vehicle include nonylphenol ethoxylated with 4 moles ethylene oxide, castor oil ethoxylated with 43 moles ethylene oxide, octylphenol plus 15 moles ethylene oxide, ethoxylated alcohols, e.g., tridecyl alcohol with 10 moles ethylene oxide, dinonylphenol with 1.5 moles ethylene oxide and ethoxylated blown oil. It is to be understood that ethoxyiates containing from about 1 to about 150 moles of ethylene oxide based on the above may be used. Esters which may be used include isodecyl oleate, methyl oleate, butyl oleate, propyl stearate, 2-ethylhexyl tallate, isopropyl myristate, phosphate esters (triethyl phosphate, tributoxyethyl phosphate, tricresyl phosphate) and plasticizers (dioctyl phthalate, butyibenzyl phthlate, glyceryl trioleate, sebacic acid esters, diisodecyl adipate, epoxidized soya oils, tributyl citrate, octylene glycol dibenzoate and polyesters). The coupling agents in the vehicle may be butyl Carbitol, butyl Cellosolve ® (2-butoxyethanol), Carbitol (diethylene glycol monoethyl ether), Cellosolve ® , hexyl Cellosolve ® , butoxytriglycol, butyl Carbitol (diethylene glycol monobutyl ether), l-butoxy-ethoxy-2-propanol, phenyl glycol ether, poly- glycols, dibutyl Carbitol, butyl Cellosolve ® acetate, Carbitol acetate, hexylene glycol diacetate and Tergitol ® XD (polyalkylene glycol ether). - 4 - Useful lecithin products for the vehicle include soya lecith alkoxylated lecithin, fractionated lecithin, hydrolyzed lecithin, hydroxylat lecithin, halogenated lecithin, sulfonated lecithin, coacervated lecithin a bleached lecithin. The vehicle may be prepared by blending the above ingredients in t desired proportions at room temperature, heating if necessary, to obtain homogeneous mixture and then cooling to room temperature. The tetrachloroisophthalonitrile is then added to the vehicle a mixed until a uniform dispersion is obtained. The antimicrobial agent is usual added slowly and dispersed by mixing from about 15 to about 60 minutes. For 50% active dispersion, the consistency or viscosity of the dispersion after mixi is about 15000 to about 30000 cps. If a lower viscosity is desired, higher she dispersing equipment must be utilized, e.g., homogenizer or 3-roll mill. T equipment will reduce the viscosity to about 7000 to about 10000 cps. T viscosity will also vary depending on- the concentration of tetrachloroisophthal nitrile present. The tetrachloroisophthalonitrile dispersion may be added to eith water-based or solvent-based protective coating formulations. From about 2 about 100 lbs of the dispersion per 100 gallons of formulation is required. T dispersion may be added to the finished protective coating formulation or may incorporated as one of the components during manufacture of the protecti coating formulation. The dispersion is useful in water-based protective coatings such acrylic, polyvinyl-acetate and vinyl-acrylic emulsions for the trade-sal coatings industry. Further, the dispersion may be used in solvent-based protecti coatings such as long oil alkyds, medium oil alkyds, short oil alkyds and linse oil based systems for the trade-sales coatings industry. Additional details both types of coatings are given on pages 500 and 501 of Volume 13 of t Encyclopedia of Polymer Science and Technology (Interscience Publishers, N York, N.Y. 1970). Because of the diverse nature of protective coatings systems, t products of this invention may be varied to increase water and/or solvent, e. polypropylene, mineral spirits, xylene dispersibility of Nopcocide N— 6. example, increasing the ' ethoxylated castor oil content will increase t dispersibility of Nopcocide N— 6 in water but will decrease the mineral spir dispersibility. Propoxylated or low (1-5 moles) ethoxylated alcohols will improve mineral spirits dispersibility, whereas ethoxylated alcohols with 15-60 moles ethylene oxide will improve water dispersibility. The stability of Nopcocide N-96 dispersions was determined by 5 placing 4 ounce samples in capped glass jars in a circulating air oven at 120° to 140°F for one month. No hard sediments, which could not be redispersed by simple stirring, formed. For a fuller understanding of the nature of this invention, reference may be made to the following examples which are given merely to illustrate the 10 invention and are not to be construed in a limiting sense. All weights, proportions and percentages are on a weight basis unless otherwise indicated. Likewise, all temperatures are °C unless otherwise indicated. EXAMPLE I A Nopcocide N— 96 vehicle was prepared using the following com- 15 ponents: parts by weight 33 Emcol D-24-25 (calcium alkylbenzene suifonate. 75% active in ethanol). 19 nonionic surfactant (nonylphenol plus 5 moles ethylene oxide). 20 30 fatty acid ester (Isodecyl oleate). 16 coupling agent (butyl Cartibol). 2 lecithin (soya). Total 100 The above quantities of the component were blended at room 25 temperature to obtain a homogeneous vehicle. A 50%, by weight, dispersion of Nopcocide N— 96 was prepared using 50 parts, by weight, of the vehicle and 50 parts of Nopcocide N— 96 by adding the biocide into the vehicle slowly and disperse for 30 minutes using a laboratory stirrer. Dispersion consistency at this stage was 17000 cps. After homogenizing 30 in a laboratory hand homogenizer, the viscosity decreased to 8150 cps (Brookfield LVF model). After aging for six weeks at 120°F, the fluid dispersion did not develop a hard, difficult to redisperse Nopcocide N— 96 sediment. " EXAMPLE II 50%, by weight, Nopcocide N-96 dispersions were prepared using t quantities of ingredients shown in Table I and I (continued). These dispersio were prepared following the procedure in Example I and are designated as 5 through Q in the table. " TABLE I NOPCOCIDE N-95 DISPERSIONS Nopcocide® N-96 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 Emcol® D-2'l-25 11.8 11.8 11.8 11.8 15.0 . 11.8 11.8 11.8 15.0 Water 5.0 5.0 5-0 5.0 5.0 5.0 5.0 5.0 • Ethoxylated (43) castor oil 11.8 11.8 11.8 11.8 Ethoxylated (1) nonylphenol 3.7 3.7 3-7 3.7 .17.0 13.9 9.5 7.0 7.5 Tergitol® XD 3.7 3.7 3.7 3.7 5.0 9.0 .1.5 7-0 7.0 Butyl Cellosolve® 8.0 Butyl Carbitol 8.0 8.0 8.0 7.3 7.2 7.2 8.0 Carbitol 8.0 Butyl oleate . 9.0 Dloctyl phthalate 9.0 Methyl oleate 7.5 Tributyl phosphate 5.0 Propeller blade vie. cpβ 31,000 20,000 16,500 28,500 21,800 24,600 22,600 31,650 26,000 3-roll milled via. cps' 8,600 7,800 7,800 15,500 7,600 9,150 9,250 13,150 16,000 TABLE I (Continued) NOPCOCIDE N- -96 DISPI ..RSIONS • J K L M . N 0 P Nopcocide® N-96 50.0 50.0 50.0 50.0 50.0 50.0 50.0 50.0 Emcol® D-21-25 16.5 16.5 16.5 16.5 16.5 16.5 10.0 Witconate® 605-T 16.5 Water 2.5 2.5 2.5 • Ethoxylated (4) nonylphenol 9.5 9,5 9.5 9.5 13.0 15.0 . 18.5 9.5 Butyl Carbitol 8.0 8.0 8.0 8.0 8.0 8.0 8.0 8.0 ' Propoxylated (90) butanol 12.5 Iaodecyl oleate 12.5 15.0 10.0 8.0 11.0 15.0 Lecithin 1.0 1.0 1.0 1.0 ?.5 2.5 2.5 1.0 UCON LB385 12.5 Propeller blade via. cps 39,000 15,750 35,000 26,750 30,000 21,500 11,500 3-roll milled vis, . cps 31,000 10,000 25,500 • Homogenized vie. < :ps 8,150 16,500 16,000 11,750 8,600 EXAMPLE III in Table I was n acrylic (50% eight of paint. affected by the .Results of the N cocide spersion 0 TABLE II PHYSICAL AND OPTICAL PROPERTIES OF 50* NOPCOCIDE N-96 DISPERSIONS IN POLYVINYL-ACEΓΛTE FORMULATION PHOTO VISCOSITY (KU) PH OPACITY DISCOLORATION SENSI 50* BIOCIDE DISPERSION LEVEL TIVITY ODOR INITIAL WK 120°F INITIAL IWK 120°F INITIAL WK 120°F INITIAL WK 120°F Control (Blank) OK OK 90 91 7.2 7-5 OK OK OK OK Nopcocide® N-96 1.0* OK OK 90 90- 7-3 .7.5 OK OK OK OK Nopcocide® N-96 2.0* OK OK 90 90 7.2 ' 7.6 OK OK OK OK Nopcocide® N-96 2.0* OK OK 90 95 7.1 7.2 ' OK OK OK OK EXAMPLE V The 50% Nopcocide N— 96 dispersion designated as Q in Table I was evaluated in a water-based protective coating formulation, a vinyl-acrylic (55% solids) system at a level of 2.0% (total weight of paint). No problems incorporating the dispersion in the formulation were encountered and no changes in film appearance of the dried coating were observed. EXAMPLE VI The 50% Nopcocide N-96 dispersion designated as Q in Table I was evaluated in a linseed-oil house paint system at a ϊewei of 2.0% (total weight of paint).. No problems incorporating the dispersion in the formulation were encountered and no changes in film appearance of the dried coating were observed. EXAMPLE VII The 50% Nopcocide N— 6 dispersion designated as Q in Table I was evaluated in a solvent-based protective coating formulation, a linseed-oil primer paint system at a level of 2.0% (total weight of paint). No problems incorporating the dispersion in the formulation were encountered and no changes in the appearance of the dried film were noted. EXAMPLE VIII The 50% Nopcocide N— 6 dispersion designated as Q in Table I was evaluated in a solvent-based protective coating formulation, an alkyd house paint system at a level of 2.0% (total weight of paint). No problems incorporating the dispersion in the formulation were noted and no changes in film appearance of the dried coating were observed. While the invention has been described with reference to certain specific embodiments thereof, it is understood that it is not to be so limited since alterations and changes may be made therein which are within the full and intended scope of the appended claims. -

Claims: - 12 - WHAT IS CLAIMED IS: 1. A tetrachloroisophthalonitrile dispersion for use as an ant 2 microbial agent for protective coating formulations comprising: 3 (a) tetrachloroisophthalonitrile, 4 (b) calcium alkyl aryl suifonate, 5 (c) nonionic surfactant, 6 (d) an ester, 7 (e) coupling agent, and 8 (f ) optionally, lecithin. 2. The dispersion of claim 1 wherein there is present 2 (a) from about 10 to about 70 parts, by weight, of tetr 3 chloroisophthalonitrile, H (b) from about 5 to about 50 parts, by weight, of calciu 5 alkyl aryl sulphonate, 6 (c) from about 5 to about 50 parts, by weight, of nonioni 7 surfactant, 8 (d) from about 5 to about 50 parts, by weight, of an ester, 9 (e) from about 5 to about 50 parts, by weight, of couplin 10 agent, and 11 (f) from 0 to about 10 parts, by weight, of lecithin. 3. The dispersion of claim 1 wherein the nonionic surfactant 2 selected from the group consisting of nonylphenol ethoxylated with 5 moles 3 -ethylene oxide, castor oil ethoxylated with 43 moles ethylene oxide, octyl phen Lf. ethoxylated with 15 moles ethylene oxide, ethoxylated aliphatic alcohol 5 dinonylphenol ethoxylated with 1.5 moles ethylene oxide and ethoxylated blow 6 oil. 4. The dispersion of claim 1 wherein the ester is selected fro 2 the group consisting of isodecyl oleate, methyl oleate, butyl oleate, prop 3 stearate, 2-ethylhexyl tallate, isopropyl myristate, dioctyi phthalate, butylbenz 4 phthalate, glyceryl trioieate, sebacic acid ester, diisodecyl adipate, epoxidiz 5 soya oil, tributyl citrate, ' octylene glycol dibenzoate, polyester, trieth 6 phosphate, tributoxy ethyl phosphate and tricresyl phosphate. 5. The dispersion of claim 1 wherein the coupling agent is 2 selected from the group consisting of butylglycol monoethyl ether, 2-butoxy- 3 ethanol, diethylene glycol monoethyl ether, butoxytriglycol, diethylene glycol -. monobutyl ether, l-butoxy-ethoxy-2-propanol, phenyl glycol ether, polyglycol, 5 hexylene glycol diacetate, polyalkylene glycol ether, diethylene glycol ihexyl 6 ether, diethylene glycol dibutyl ether, ethylene glycol monoethyl ether, ethylene 7 glycol monohexyl ether, ethylene glycol monoethyl ether acetate, diethylene 8 glycol monoethyl ether acetate and ethylene glycol monobutyl ether acetate. 6. The dispersion of claim 1 wherein there is present about 33 2 parts, by weight, of calcium alkylbenzene suifonate, 19 parts, by weight, of 3 nonylphenol condensed with 5 moles of ethylene oxide, 30 parts, by weight, of i f . isodecyl oleate, 16 parts, by weight, of diethylene glycol butyl ether, 2 parts, by 5 weight, of soya lecithin and 100 parts, by weight, of tetrachloroisophthalonitrile. 7. A process of preparing a water-based protective coating 2 formulation containing tetrachloroisophthalonitrile as an antimicrobial agent 3 comprising adding to the formulation or adding as a component during ij. manufacture of the formulation the dispersion of claim 1, the amount added 5 providing for an effective amount of the tetrachloroisophthalonitrile. 8. A process of preparing a solvent-based protective coating 2 formulation containing tetrachloroisophthalonitrile as an antimicrobial agent 3 comprising adding to the formulation or adding as a component during 4 manufacture of the formulation the dispersion of claim 1, the amount added 5 providing for an effective amount of the tetrachloroisophthalonitrile. 9. The process of claim 7 wherein the dispersion is added to the 2 protective coating formulation. 10. The process of claim 8 wherein the dispersion is added to the 2 protective coating formulation. 11. A water-based protective coating formulation containing 2 tetrachloroisophthalonitrile as an antimicrobial agent, there being present the 3 dispersion of claim 1, the amount of the dispersion present providing for an effective amount of the tetrachloroisophthalonitrile. - 14 12. A solvent-based protective coating formulation contain tetrachloroisophthalonitrile as an antimicrobial agent, there being present t dispersion of claim I, the amount of the dispersion present providing for effective amount of the tetrachloroisophthalonitrile.

Inventors: ALDERMAN J, IHDE F, MAKAR P
Applicants: DIAMOND SHAMROCK CORP
Application year: 1979
Main classification: A01N9
IPC codes: A01N25, A01N37, C09D5