CH646688A5 - PEROXIDE EMULSIONS AND SIZING COMPOSITION CONTAINING THE SAME. - Google Patents

Description

The invention presented here relates to an aqueous emulsion prepared from a solid organic peroxide, a sizing solution containing this emulsion and sized glass fibers. In particular, the invention presented here relates to an aqueous peroxide emulsion made from a solid organic peroxide, an aqueous treatment solution containing the same and sized glass fibers prepared to be bound to polymers in the reinforcement of polymer-based materials.

Organic peroxides which decompose by splitting their oxygen-oxygen bond by producing free radicals serve as initiators for the polymerization of vinyl monomers, or other products containing a vinyl group. There are over fifty different organic peroxides which are grouped into nine main categories and which are used in the resin and polymer industries. The half-life duration (T yJ, which varies depending on the temperature, can be understood for the various peroxides between a short half-life of 0.01 h at low temperature and a long half-life of 1000 h at high temperature (around 160 ° C) The half-life is a measure of the thermal stability of organic peroxides; it is obtained by measuring the time required for decomposition of 50% of the original amount of peroxy, time which corresponds to a half-life duration for a first order reaction.

These organic peroxides have been used in the polymerization of vinyl monomers to make crude polymers, polymer films or other polymer compositions.

Various organic peroxides can be used in different forms in their use as initiator of the polymerization reaction of vinyl monomers, this depending on their thermal stability or other physical properties of the peroxides concerned. Some organic peroxides, such as highly reactive percarbonates, are so unstable that they must be transported as a frozen solid or an undiluted liquid kept under refrigeration.

Some less reactive organic peroxides, such as lauroyl peroxide or dibenzoyl peroxide, are more stable at room temperature and can be activated more easily and with less care. For example, dibenzoyl peroxide, which is relatively more stable and which is in solid form at room temperature, with a melting point of 106-107 ° C, can be used in the form of granules or crystals, or in the form a thick paste mixed with a protective agent such as tricresyl phosphate. In addition, dibenzoyl peroxide can be used in an aqueous solution, as disclosed in US Patent No. 2,343,084 (Smith), where a small amount of benzoyl peroxide is dissolved in one or more polymerizable conjugate compounds, and it may also contain dissolved resin. This solution can be combined with an aqueous solution of partially saponified polyvinyl acetate. Likewise, US Pat. No. 3,795,630 (Jaspers et al.) Has suggested a composition containing an organic peroxide which is chemically stable, the latter being solid at room temperature. This composition is obtained by mixing the solid peroxide, such as benzoyl peroxide,

with a liquid protective agent such as phthalate plasticizers, epoxidized soybean oils or glycols, and with a hydrophobic alkyl containing silicon. Furthermore, it has been shown in US Patent No. 4039475 (Jannes) that a stable aqueous suspension of an organic peroxide can be pumped and which contains a nonionic emulsifier having a maximum HLB index of 12.5 and a second non-ionic emulsifier having a minimum HLB index of 12.5, or else the second emulsifier is of the anionic type.

Organic peroxides such as arylalkyl peroxides, such as dicumyl peroxide, ester peroxides and aromatic and aliphatic acyl peroxides have been used for the sizing of fibrous materials used in applications with polymers, such as this is described in US Patent No. 3013915 (Morgan) for example. These peroxides, which have low volatility and low decomposition temperatures, generally below 82 ° C (180 ° F), are deposited from an organic solution. Along with these peroxides, there is an appropriate coupling agent in this solution.

On the other hand, as is disclosed in US Patent No. 3,837,898 (McCombs et al.), The preparation of a polybutadiene emulsion which contains heat activated polymerization agents which act as catalysts in the fiber sizing. These polymerization agents are free radical catalysts which are well known, such as organic peroxides, for example benzoyl peroxide, lauroyl peroxide, tert.-butyldiethyl peracetate, diacetyl peroxide, as well as mineral peroxides such as potassium persulfate. The polybutadiene emulsion is prepared by mixing the polybutadiene with an emulsifier and benzoyl peroxide. To this mixture is added enough water to form an aqueous emulsion of the liquid polymer. This emulsion is then added to a mixture of water, anchoring agents for glass fibers and gelling agents, and the resulting composition is homogenized to form a sizing solution having a solids content of approximately 2 , 80% by weight and a pH of about 10.0 to 10.5. The emulsifiers which can be used are any usual emulsifier, but preferably they are of the nonionic type, such as polyoxyethylenated fatty acid derivatives, partial esters of sorbite anhydrides or polyoxyethylenated derivatives of fatty alcohols or phenols substituted by alkyl groups.

It has recently been suggested, in US Pat. No. 3,849,148 (Temple), to prepare an aqueous sizing solution for glass fibers which will be used in the reinforcement of materials based on polyolefins, this sizing solution containing an agent coupling agent, a heat-stable organic peroxide, a nonionic surfactant and, usually, a lubricant or plasticizer, and optionally a film-forming agent. Organic peroxides which are thermally stable include organic peroxides which have decomposition temperatures above about 93 ° C (200 ° F), such as: a, a'-bis (t-butylperoxy) diisopropylbenzene, tris- (t-butylperoxy) diisopropyl-benzene, 2,5- (t-butylperoxy) hexane and 2,5- (t-butylperoxy) -hexyne. These thermally stable peroxides are used in emulsions in the company of nonionic surfactants such as polyethoxyphenols, these being prepared in water containing a coupling agent.

Emulsions prepared at temperatures between 49 ° C (120 ° F) and 99 ° C (210 ° F) which contain isooctylphenylpoly-ethoxyethanol are particularly suitable. Other suitable nonionic surfactants are those which belong to the class of polyethoxyphenols such as nonylpolyethoxyethanol and

5

10

15

20

25

30

35

40

45

50

55

60

65

646 688

4

alkyl ethers of polyethoxyethanol. Other nonionic surfactants which are also suitable are polyalkylene glycol ethers, polyether alkyl alcohols, polyether alkyl aryl alcohols. The emulsion is prepared by vigorously mixing the precursor peroxide with the nonionic surfactant, this keeping the temperature of the mixture above the melting point of the peroxide. The temperature can easily be adjusted by immersing the mixing reactor in a boiling water bath. After carefully mixing the free radical peroxide with the nonionic surfactant, water is slowly added to the mixture,

this at a temperature above the melting point of the free radical initiator peroxide, and preferably between 60 ° C (140 ° F) and 66 ° C (150 ° F), until the emulsion reverses. The emulsion is slowly cooled to room temperature by continuous addition of water. This emulsion is then poured slowly into an aqueous mixture containing the coupling agent and, finally, the rest of the water is added to form a sizing composition intended for the treatment of glass fibers.

When preparing the emulsion used in the composition of the sizing solution for glass fibers, it is necessary to obtain an emulsion containing small particles which is stable during storage and during processing. work, that is to say that the particles of the internal phase must not coalesce when the emulsion is brewed or when it is stored for a certain time, or when it is applied to the glass fibers. It is necessary to have an emulsion rather than a dispersion which is limited by the size of the particles. An emulsion is a two-phase system consisting of two partially miscible liquids, one of which is dispersed as fine droplets in the other, while a suspension is a two-phase system in which the dispersed phase is solid.

The size of the particles and their distribution in an emulsion are controlled by factors such as the quantity or effectiveness of the emulsifier, the order in which the mixture is made and the type of agitation used. The stability of an emulsion depends on factors such as 1) the particle size, 2) the difference between the density of the body of the internal phase, which is the liquid divided into fine droplets, and that of the external phase, which is the surrounding water, 3) the viscosity of the emulsion, 4) the particle charges, 5) the choice of the type of emulsifier and its quantity, and 6) the conditions of storage and use, this including storage and use temperature, agitation, dilution and evaporation.

The average particle size and their distribution in an emulsion are controlled by factors such as the amount or effectiveness of the emulsifier, the order in which the mixture is prepared and the agitation used. The average particle size and the size distribution of these particles in the emulsion are important parameters in that large liquid particles, or droplets, in the case of an emulsion, or large solid particles, in in the case of a suspension, would not provide an adequate uniform coating on the glass fibers. In addition, the solid particles could have an abrasive effect on the glass fibers, and large liquid particles would cover the glass fiber in a discontinuous manner, leaving gaps along the fiber, which would result in the fiber not being not in adequate contact with the resin matrix which it must reinforce.

The emulsion used in the composition of a sizing solution for glass fibers must be diluted until a liquid having the consistency of water is obtained, this to facilitate its application to glass fibers during their manufacturing.

The dilution of an emulsion, especially until a liquid with the consistency of water is obtained, can cause its instability. Likewise, the emulsion of the sizing composition must be rheologically stable to support stirring during the preparation of the sizing solution before its application to the glass fibers.

In addition, the emulsion must be stable during its storage, this for a period varying between three d and more than a week, so that the product can be stored before its application to glass fibers. Likewise, the emulsion must be stable during its implementation, so that it can be applied to the glass fibers.

A problem that has arisen recently in the use of solid organic peroxides which are thermally stable is the fact that, when used in an emulsion which is prepared at temperatures above the melting point of the peroxide, it is found that when from using this emulsion at temperatures that are below the melting point of the peroxide, the particles tend to settle or collect on the surface.

An additional problem that arises in the use of organic peroxides in aqueous processing solutions is the risk of violent decomposition during emulsification. Since the solid peroxides must be heated to melt them, the use of high temperatures brings the peroxide close to its decomposition temperature and, possibly, violent decomposition can occur if this is reached.

It is an object of this invention to provide a safer process for preparing an emulsion of an organic solid peroxide which has a high melting point and a high decomposition temperature.

Another object of this invention is to provide an emulsion of a solid peroxide which can be diluted to reach a viscosity close to that of water, and which has better stability with regard to rheology, storage time. and workability.

Another object of this invention is to provide an emulsion of a thermally stable organic peroxide which can be used in a sizing composition for glass fibers, the latter being stable from the point of view of rheology, the duration d storage and workability in the sizing composition.

Another object of this invention is to provide a process for preparing a thermally stable organic peroxide emulsion and a sizing composition containing it, in which the peroxide emulsion can be more easily diluted, this emulsion moreover being more stable with regard to rheology, storage time and workability and having particles of small dimensions which are closely distributed.

Another object of this invention is to provide glass fiber yarns covered with an aqueous sizing composition containing a coupling agent, an emulsion of a thermally stable organic peroxide, an emulsion which can be better diluted and which has a better stability with regard to rheology, storage time and workability, and which has a narrow distribution of small particles; and usually containing a lubricant or plasticizer and, optionally, a film-forming agent.

The average particle size and the distribution of these dimensions in the emulsion are important factors, since large liquid particles in the emulsion or large solid particles in a suspension would not effectively cover the surface of the fibers. glass and tend to separate from the sizing composition, and hard solid particles in the sizing composition could have an abrasive effect on the glass fibers.

The objects mentioned above, as well as other objects of the invention presented here, which could be gleaned in the description which follows, are achieved by means of an oil-in-water emulsion of an organic peroxide which is solid at 20 ° C. and which forms radicals active at high temperature and which, on the other hand, is insoluble in water or which has limited solubility in water, this emulsion additionally containing one or more hydrocarbon solvents, one or more emulsifiers having an overall HLB index between about 9 and about 20 and water.

Solid peroxides which are insoluble, or which have limited solubility in water, include hydroperoxides, a-oxy- and a-peroxyhydroperoxides, dialkyl peroxides, aldehyde and ketone peroxides, diacyl peroxides , peroxy-esters, peroxyacids, peroxydicarbonates, peroxymono-carbonates and percetals.

5

10

15

20

25

30

35

40

45

50

55

60

65

5

646 688

The hydrocarbon solvent used in this invention can be any weakly polar and highly hydrophobic solvent such as pine oils, white spirit, special boiling spirits and aromatic solvents. The hydrocarbon solvent (s) have a kauri / butanol number between about 50 and about 100 when the solid peroxide has an aromatic character, or else they have a kauri / butanol number between about 10 and about 50 when the solid peroxide has an aliphatic character. Character, taken in this sense, means that the major portion of the peroxide molecule is aromatic with aromatic or aliphatic substituents, or when it is aliphatic with aliphatic or aromatic substituents. In addition, it is beneficial to have a fugitive hydrocarbon solvent which can be removed from the aqueous emulsion when the latter dries on the substrate.

This emulsion also contains one or more emulsifiers having an apparent HLB index (hydrophilic-lipophilic balance = hydrophilic-lipophilic equilibrium) located between approximately 9 and approximately 20. Non-exhaustive examples are represented by the emulsifiers of the following types: polyethoxyphenols, polyalkylene glycol ethers , polyether alkyl alcohols, polyether alkylaryl alcohols, ethylene oxides, ethoxylated alcohols; ethoxylated alkylphenols, ethoxylated fatty acids, fatty esters and oils, fatty acids, glycerol esters, glycolic esters, monoglycerides and their derivatives, sorbite derivatives, and sucrose esters and their derivatives, condensation products of alkylated phenols and condensation products of condensation ethylene oxide and propylene glycol, these being taken in sufficient quantity to emulsify the organic peroxide. These emulsifiers are most effective when a mixture of three of the emulsifiers chosen from the list mentioned above is chosen, each of them being taken in an amount such that the overall HLB index of the mixture is between approximately 9 and around 20.

The emulsion also contains sufficient water to produce an oil-in-water emulsion. If the emulsion has to be transported over a long distance, the quantity of water which is then added is that which is just sufficient to transform most of the insoluble product, or product with limited solubility, into an emulsion of the oil type in the water, which produces a concentrated oil-in-water emulsion. This concentrated emulsion can then be further diluted at the place of use.

The emulsion of an organic peroxide which is described above has several uses in the polymerization of vinyl and olefin polymers. This emulsion is particularly suitable for the preparation of a sizing composition for glass fibers which will be used in polymer-based materials. This sizing composition is an aqueous composition which contains a coupling agent, the peroxide emulsion and, usually, a lubricant or plasticizer with optionally a film-forming agent.

The process used to prepare the emulsion containing the organic peroxide consists first of dissolving the solid organic peroxide in the hydrocarbon solvent, then adding one or more surfactants, and finally water, and emulsifying the whole using the equipment. and techniques known in the art.

The aqueous sizing solution containing the emulsion of organic peroxide is used to treat glass fibers during the manufacture of these. The glass fibers thus treated are heated to remove most of the water from the sizing composition, and the treated and dry glass fibers are used to bind or to reinforce polymers such as homo- or co-polymers , polyolefins, polyamides, polyesters and the like.

The solid organic peroxides which are insoluble in water, or which have a limited solubility in it, and which are most suitable for entering into the aqueous sizing composition are those which have the formula:

(R — O — O—) X-R '

wherein R is a tertiary alkyl, aralkyl, aroyl or acyl group; x is a number which is 1, 2 or 3, and R 'is identical to R, or else it has the structure:

R "R"

I I

C — RIV — C

I I

R '"R'"

in which RIV is a phenyl, alkylphenyl, alkyne or alkyl group having the structure:

(CH2-CH2) n-

where n is 1, 2 or 3, and R "and R '" are either hydrogens, or individual hydrocarbon radicals, or bonded alkylene radicals which form a cycloalkylene radical. Either of R "and R '" can be alkyl, cyacloalkyl, aralkyl or aryl hydrocarbon groups, when RIV is a phenyl group, or the hydrocarbon groups R "or R'" are groups phenyls, aryls or groups larger than C7H15 when RIV is a group (CH2 — CH2) n. The group R — O — O - can be linked to any position on the group R ′ is a di- or trialkylbenzene in which the alkyl substituents are located in any position such as ortho, meta and / or para, or then in position 8,11 when R 'is the group (CH2 — CH2).

In the preparation of an emulsion which is better diluted, which is more stable and safer, the following bodies can be taken as solid organic peroxide which is not soluble in water:

2,5-dihydroperoxy-2,5-dimethylhexane; 1,4-dihydroperoxy-1,4-dimethylbutane; 1,4-dihydroperoxy-1,4-dimethyl-2-butyne; 1,3- and 1,4-bis (hydroperoxyisopropyl) benzene; bis- (l -hydroxycyclohexyl) -peroxide, l-hydroperoxy-l'-hydrodicyclohexyle, dicumyl peroxide, 2,5-di (hydroperoxy) -2,5-dimethylhexyne, 2,5-di- (hydroperoxy) - 2,5-dimethylhexane and hydroperoxides having the following structural formulas: tert.-butyl — CMeEt — O — OH; HO - O - C [<(CH2) 5] - C - C - [<(CH2) 5] - O - OH;

HO — O — C - [<(CH22) s] —C — C C-C-C - [<(CH2) 5]

- C — O — OH; 1,3-and 1,4- (ditert.-butylperoxyisopropyl) benzene; 8, ll-bis (tert.-butylperoxy) -8, ll-dimethyloctadecane, and mixtures thereof; tribenzyltert.-butyl bisperoxide, ditetra-decane peroxide, dihexadecane peroxide, ditribenzylmethyl peroxide; dilauroyl peroxide; didecanoyl peroxide, di-pelargonyl peroxide, dicaprylyl peroxide; diisononanoyl peroxide; dibenzoyl peroxides and derivatives with substituents on the nucleus thereof; 2,5-dimethyl-2,5-di (benzoylperoxy) hexane; dimyristyl peroxydicarbonate, diketyl peroxydicarbonate; bis- (4-tert.-butylcyclohexyl) per-oxidicarbonate; 2,2-bis-4,4-ditert.-butylperoxycyclohexylpropane; 1,1-ditert.-butylperoxy-4-tert.-butyl-cyclohexane; 2,5-bis (tert.-amylperoxy) -2,5-dimethylhexane; 1,1'-ethylenebis-1- (tert.-amylperoxy) cyclohexane; 2,5-bis (tert.-butylper-oxy) -2,5-diphenylhexane; 2,6-bis (tert.-butylperoxy) -3,6-dimethyl-octane; a, a, a ', a'-tetramethylisophtalyldi-t-butyl bisperoxide, and a, a, a', a'-tetramethylisophtalyldicumyl and tris- (t-butylperoxy) diisopropylbenzene bisperoxide.

An aqueous emulsion can be prepared with any of the above peroxides, which are in solid form and which are insoluble or poorly soluble in water; this emulsion is more easily diluted, it is more stable and safer and it has a narrow distribution of fine particles; this is obtained by the use of an organic hydrocarbon solvent and one or more emulsifiers, and by an emulsification with water.

The particular hydrocarbon solvents, emulsifiers and the process for preparing the emulsion are the same for any solid organic peroxide from the above list, which is insoluble or sparingly soluble in water.

The solid organic peroxides, which are insoluble or poorly soluble in water, for which the aqueous emulsion and its method of preparation are most suitable, are those which have a melting point which is closer to their decomposition temperature.

10

15

20

25

30

35

40

45

50

55

60

65

646 688

6

room temperature. For these, the rise in temperature which is necessary to obtain their fusion presents a risk due to its proximity to the decomposition temperature. This can result in a violent decomposition reaction, especially in production facilities that are poorly controlled.

The emulsion and its preparation process are also suitable for thermally stable peroxides, since these can also have a melting point which is close to their decomposition temperature.

The most thermally stable organic peroxides can be used as sources of free radicals in the polymerization of monomers or polymers containing vinyl groups or double bonds. By thermally stable peroxides is meant peroxides which have a half-life of more than 60 h at 100 ° C (212 ° F) and more than 20 min at 149 ° C (300 ° F). The half-life is a measure of the reactivity of the peroxide; it is defined as the time necessary for the decomposition of half of a given quantity of peroxide at a certain temperature.

Thermally stable peroxides which are particularly suitable are those which have the following formula:

R "R"

I I

(R — O — O—) x — R 'where R' is C-R ^ -C

I I

R '"R"'

As non-exhaustive examples of these peroxides, mention may be made of solid dialkyl and diaryl peroxides such as bis (tertiary alkyl-peroxy) alkanes in which R is a tertiary alkyl group containing between 4 and 8 carbon atoms and either R "or R "'is a primary alkyl group containing between 1 and 8 carbon atoms, while the other group contains more than three carbon atoms. As additional examples, there may be given: 2,5-bis (tert.-amylperoxy) -2,5-dimethylhexane, 1, l'-ethylenebis- [1- (tert.-arylamylperoxy) cyclohexane]; 2,5-bis (tert.-butylperoxy) -2,5-diphen-ylhexane; 3,6-bis (tert.-butylperoxy) -3,6-dimethyloctane. Non-exclusive examples of diaralkyl peroxides which can be used are represented by the following bodies: 1,3- and / or 1,4- (ditert.-butylperoxy) diisopropylbenzene, or a, a, a ', a'-tetramethylisophthalyl -ditert.-butylbisperoxide, a, a, a ', a'-tetramethylisophtalyldicumylbis-peroxide and tris (tert.-butylperoxy) diisopropylbenzene. Other dialkyl peroxides which can be used include 2,5- (tert.-butylperoxy) hexane, 2,5 (tert.-butylperoxy) hexyne and 8,11-bis- (tert.-butylperoxy) -8, 11-dimethyloctadecane. In addition, tert-alkyl peroxyesters which are known as perester and which are more stable can also be used. These peresters include tert.-butyl peracetates, tert.-butyl perbenzoate, ditert.-butyl diperoxy-phthalate, monotert.-butyl permaleate, ditert.-butyl peroxy-hexahydroterephthalate, ditert.-butyl peradipate, ditert.-butyl peroxyterephthalate and monotert.-butyl peroxyphthalate. The amount of solid peroxide used in the emulsion is that which causes a concentration of active solid peroxide in the sizing solution which is between about 0.1 and about 6.0% by weight. In general, this amount can vary between about 1 to 70% by weight of the emulsion, and its lower limit is at least 10% by weight when used in sizing compositions.

The fleeting organic solvents which can be used in the solubilization of solid organic peroxides will, if they are predominantly aliphatic, have a low kauri / butanol index,

between about 10 and about 50, and boiling points between room temperature and about 200 ° C. If the organic peroxide has more than about 60% of aromatic characters, the hydrocarbon solvent will have a kauri / butanol index located between approximately 50 and approximately 100, with boiling points situated between approximately 100 and 250 ° C. The kauri / butanol index is a measure of the dissolving power of petroleum thinners where the value is the number of milliliters of solvent required to cause haze when added to 20 g of a solution of kauri gum in butyl alcohol. This solution is prepared by dissolving 100 g of kauri gum in 500 g of butyl alcohol. Solvents with a low aromatic character strongly precipitate the resin and therefore give low values. Conversely, solvents with a strong aromatic character give high values. This kauri / butanol index is preferably determined in the company of a standard which is toluene, having an index of 105, if the hydrocarbon solvent gives a kauri / butanol index which is greater than 60, or else a mixture of 75 % n-heptane and 25% toluene when the hydrocarbon solvent has an index of 40. This determination is described in publication ASTM No. D. 1133-54 T. Isoparaffinic hydrocarbon solvents have a low kauri / butanol index and are used when the organic peroxide has a strong aliphatic character or a weak aromatic character, if present. As suitable examples of these solvents, mention may be made of isoparaffinic solvents sold by Exxon Company USA under the registered name of Isopar, or by Phillips Petroleum under the registered name of Soltrol, which have boiling points situated in the given range above.

As examples of hydrocarbon solvents having a high kauri / butanol index, there may be mentioned the commercially available solvents under the names of Hi-Sol-10 and Hi-Sol-15 which are produced by Ashland Chemical Co., Ohio, the Hi-Sol-10 having a boiling point of 153 ° C (308 ° F), a flash point of 40.6 ° C (195 ° F), and a volatilization rate of 25.0 using I ' ether as reference to 1. It is also possible to use the hydrocarbon solvents sold by Exxon Co. USA, a division of Exxon Corp. Company, under the names of Solvesso 150 or Solvesso 100.

The ratio of organic peroxide to the hydrocarbon solvent is at least a ratio of 1 to 0.75 when the hydrocarbon solvent has a kauri / butanol number of 70. If the solvent is a better solvent for the peroxide, as is the case for Hi-Sol-10, which has a kauri / butanol number of 92-93, when the peroxide is a, a'-bis (tert.-butylperoxy) diisopropylbenzene, the minimum amount of solvent which could then be used would be less than the amount given by the above ratio, such as for example for 1 part of peroxide it would suffice to use about 0.4 part of solvent, or even 0.19 part. When the solvent is a poorer solvent than that which has a kauri / butanol number of 70, when the organic peroxide is Pa, a'-bis (tert.-butylperoxy) di-isopropylbenzene, then the minimum amount of solvent would be greater than that given by the above report. The amount of solvent which is used in the preparation of the emulsion of the solid organic peroxide will be, in general, in the range between about 1 to about 70%, and preferably between about 10 and about 55% by weight of the 'emulsion. More solvent can be used, but there is no benefit to be gained from the fact that it is usually removed in later stages.

The nonionic emulsifiers are preferably chosen from polyethoxyphenols, polyalkylene glycol ethers, poly (alkyl ether alcohols, poly (alkyl ether alcohols), condensation products of ethylene oxide with alkylphenols, and condensation products of condensation. ethylene oxide with propylene glycol, which have an HLB number between about 9 and about 20, and they can be used alone or in admixture to obtain the desired HLB number. As an example of an emulsifier used alone, mention may be made of octylphenoxypolyethoxyethanol, available from Rohm and Haas Company under the trade name of Triton X-100, which is non-ionic and which has an HLB index of 13.5. These types of emulsifiers, such as Triton X-100, can be prepared from phenols substituted by alkyl groups in which the alkyl group contains between 6 and 12 carbon atoms. The number of moles of ethylene oxide per mole of alkylphenol (hydrophobic part) can vary between 1.5 and approximately 30. The weight percent of combined ethylene oxide usually varies between approximately 40 and approximately 95 to get good water solubility, and it's ty5

10

15

20

25

30

35

40

45

50

55

60

65

7

646 688

between about 60 and about 95. Another example of such an emulsifier is nonylphenoxypoly (ethylenoxy) ethanol. To obtain the desired HLB index, it is not necessary to use only one emulsifier. Any mixture of two or more Surfactants with known HLB indices can be used, combining the various Surfactants in appropriate proportions, and, if the HLB index of one of the emulsifiers is not known, it can be calculated from several known formulas. On this subject, see the article by E.C. Grifïïn entitled "Calculation of HLB Nonio-nic Surfactant" in the December 1954 edition of the "Journal of the Society of Cosmetic Chemistry". Typically, the emulsifier constitutes between about 1 and about 15% by weight and, normally, between about 3 and about 12% by weight of the emulsion. The exact amount of emulsifier that is required can be easily determined by trial and error using the areas indicated as starting points.

When a stable emulsion has been obtained, the use of a surplus of emulsifier is not necessary, since it does not bring any additional advantage and could even prove to be a disadvantage of the fact that this would cause removing the aqueous treatment solution containing the emulsion from the treated substrate, such as for example a set of fibrous materials.

It is particularly practical to use a mixture of three emulsifiers in the emulsion of the invention presented here. The three emulsifiers are chosen with appropriate weight ratios to give an overall HLB index which is in the range between approximately 9 and approximately 20, and preferably between 9 and 15. One of the emulsifiers is chosen from those which have a high HLB index. , located between approximately 12 and approximately 20. The second emulsifier has an HLB index situated between approximately 6 and approximately 12, and the third emulsifier has an intermediate HLB index situated between approximately 9 and approximately 15. The three emulsifiers are taken in such quantities that a total HLB index of between about 9 and about 20 is obtained. It is particularly effective to take equal amounts of each emulsifier, although different proportions can be used to obtain the desired HLB index.

To prepare the emulsion of the invention presented here, one or more of the selected peroxides are dissolved in the fugitive hydrocarbon solvent suitable for the chosen peroxide. This mixture can be moderately heated to facilitate dissolution of the peroxide. The emulsifier (s) is added to this solution and emulsified, using the usual techniques, conditions and equipment. When the emulsifier is composed of three different emulsifiers, they can be added separately to the mixture of the peroxide and the hydrocarbon solvent, or a mixture of two emulsifiers can be added first and then the third, or then all three at the same time.

When the emulsifiers have been added, the emulsification of the mixture is carried out using techniques and apparatuses usually used. Such techniques include, among other things, that of subjecting the mixture to high viscosity forces and then diluting it slowly with water, which may be at room temperature or at a higher temperature.

Water is added until the emulsion reverses to an oil-in-water emulsion, and the emulsion is then slowly cooled to room temperature by the addition of water. The amount of water which is added to the emulsion represents at least 35% of the composition of the emulsion. If the emulsion is to be transported over a long distance, the minimum quantity of water which is then used is that which causes most of the body, insoluble, or sparingly soluble, in water to be inverted into an emulsion of oil in water type.

The emulsion is then transformed into an aqueous sizing composition by the addition of a coupling agent, a lubricant or plasticizer, usually, and optionally a film-forming agent. This preparation comprises the slow addition of the emulsion to an aqueous mixture containing the coupling agent, the lubricant or plasticizer and the film-forming agent, followed by the addition of the rest of the water to thus complete the aqueous composition. of size. Likewise, the lubricant or plasticizer or the film-forming agent which will be used in the composition can be added after the emulsion has been added to the aqueous mixture containing the coupling agent. The amount of emulsion incorporated into the sizing solution depends on the amount of peroxide contained in the emulsion. The amount of emulsion used is that which provides an amount of organic peroxide of between about 0.1 and about 6% by weight of the sizing solution. When the emulsion of this invention has been prepared, it can be included in an aqueous sizing solution by following the method described by US Patent No. 3,849,148 (Temple), which is cited by reference.

Usually, the amount of organic silane coupling agent, which is generally a silane containing a vinyl group, which is used in the sizing solution is in the range between about 0.5 and 10% by weight of the aqueous sizing solution. The amount of lubricant used in the sizing solution, a lubricant which is generally an amide of an acid-soluble and cationic fatty acid, is usually between approximately 0.001 and approximately 1% by weight of the aqueous sizing solution .

If a film-forming agent is used, it is normally a polyvinyl acetate polymer or a copolymer, this in an amount between about 0.05 and about 12% by weight of the sizing solution.

The aqueous sizing solution is applied to the individual glass fibers during their formation, by any known method. Such methods are described in US Patent No. 3,849,148 (Temple), which is cited as a reference.

The glass fibers are dried to remove moisture and fugitive hydrocarbon solvent residue therefrom, although some may remain on the fibers. These dry glass fibers can be used in any form, such as for example in the form of fibers, yarns, pieces of dry or wet yarns, webs, and other similar forms intended for the reinforcement of polymers such as polyamides, polyesters, and particularly polyolefins.

The layers of glass fibers intended for the reinforcement of polyolefins are described in US Pat. No. 3,849,148, which presents the manufacture of laminates of polyolefins reinforced with glass fibers, a patent which is cited here by reference.

Preferred forms of execution

The emulsion of the invention presented here is preferably an emulsion of a, a'-bis (tert.-butylperoxy) diisopropylbenzene containing the meta and para isomers, which is commercially available from Hercules, Inc. under the name Vulcan Cup R vulcanizing agent and polymerization catalyst

The solid peroxide is used according to a ratio of the peroxide to the hydrocarbon solvent such that the solubilization of the peroxide is easy, but this ratio of the peroxide to the solvent is preferably between 50/50 and 70/30, and even better around 60/40. The hydrocarbon solvent is preferably a solvent which is commercially available under the name Hi-Sol-10, produced by Ashland Chemical Company.

The organic peroxide is dissolved in Hi-Sol-10, the amount of this being between approximately 10 and approximately 30% by weight of the aqueous emulsion.

In the preparation of the emulsion according to the invention presented here, a mixture of three emulsifiers is preferably used. The first of these is a polyethylene glycol trimethylnonyl ether, such as that which is commercially available under the name of Tergi-tol TMN-6, produced by Union Carbide, which has an HLB index of 11.7. This ether is used in an amount of between about 0.1 and about 5% by weight of the emulsion. This emulsifier is mixed with a second emulsifier which is a nonylphenoxypoly-ethylenoxyethanol, available from GAF Corporation Chemical Products under the name Igepal CO-630, having an HLB index of 13, and it is used in an amount of between approximately 0 , 1 and

5

10

15

20

25

30

35

40

45

50

55

60

65

646 688

8

about 5% by weight of the aqueous emulsion. These two emulsifiers are stirred until a clear solution is obtained. The third emulsifier is a product of the condensation of propylene oxide with hydrophilic bases obtained by the condensation of ethylene oxide with ethylene glycol; this product is available from 5 BASF Wyandotte Industriai Chemical Group under the name of Pluro-nic P-65. It has an HLB index of 17 and is used in an amount between about 0.1 and about 5% by weight of the emulsion. The total amount of mixture of the three emulsifiers in the aqueous emulsion constitutes between about 1 and about 15% (and preferably between about 3 and about 12%) by weight of the sizing composition. More than 15% by weight could be used, but this would cause the sizing solution to shrink on the glass fibers.

It is preferred to add the emulsifier mixture as follows. The amount of the glycoloxide emulsifier is divided into two portions. The first, about half of the total amount, is added to the peroxide dissolved in the solvent at the same time as the mixture of the other two emulsifiers.

The rest of this glycol-based emulsifier is dissolved in water with stirring, in a mixture of about 50/50, and added to the other ingredients during the emulsification. This emulsification consists in brewing the products by adding a quantity of hot water, the temperature of which is between approximately 25 and 30 ° C., and which represents approximately 15 to 30% by weight of the composition 25 of the aqueous emulsion. .

Cold water is then added to bring the concentration of active peroxide in the aqueous emulsion to the range between about 35 and 65%, and preferably around 50% by weight of the aqueous emulsion. 30

This aqueous emulsion is preferably added to an aqueous composition containing a coupling agent, which is preferably vinyltris- (P-methoxyethoxy) silane, present in an amount of between approximately 0.5 and approximately 10% by weight of the aqueous sizing composition. According to another embodiment, a lubricant such as Emerylube 6717, available from Emery Industries, can be included in the sizing composition, this in an amount which can be between approximately 0.001 and approximately 3%. weight of the aqueous sizing solution.

In another embodiment, a film-forming agent such as a vinyl acetate copolymer is used, in an amount between about 0.5 and about 12% by weight of the aqueous sizing composition.

The amount of water included in the aqueous sizing solution is normally between about 70 and about 99% by weight 45 of the sizing composition.

This aqueous sizing composition is applied to the individual glass fibers during their manufacture, as described in US Patent No. 3,849,148 (Temple), cited here for reference. The aqueous peroxide emulsion can be used in any of the sizing compositions given in US Patent No. 3,849,148.

The following examples describe in more detail the aqueous emulsion of this invention.

Table I gives examples in which the various components are expressed according to their weight in grams and their percentage by weight. >

In Table I, emulsion No. 5 was prepared by first melting the organic peroxide on a hot water bath 60 to 60-66 ° C (140-150 ° F). The hydrocarbon solvent is then added with stirring. Continuing the agitation, the emulsifiers of ether type and ethanol type are then added. This mixture is then subjected to high speed stirring in an Eppenbach mixer,

without heat, to disperse the emulsifiers evenly. Half of the total amount of emulsifier based on propylene oxide and ethylene oxide condensate is then added, and this mixture is stirred for approximately 10 min. The other half of the latter emulsifier is mixed with water and the whole is added to the preceding mixture, with continuous stirring. This two-step addition avoids the possible salification of the emulsifier. Then pour cold water into the Eppenbach mixer

Table I Tests

Tf OS

—R m o K

\ o es o \ p m es

VO -

M, V)

O VO TT O

gold-

fo es

O OO

r »es

2 ^

o o

es.

</ ") ON

es "OO es 00

a o

"O ^ I -

o es o * / i r- m es

- 1

vo c -o a us n®

0 o £

• g io 'O

§ o "8. i -H" -S o

M B ">

1 8 -s in 5

o • o

"X o" O -s

'H.,

O

"* O>

s® C c jd

'S 3 «0 w a 2 * 2

Ä "-o o jï" Q ">" 'g- 3 X -l P ÇJ - o o Z. c co O 3 S .A'

.2> I X I co

CM

4>

S 3

Jï o *

o -a x / i ";

ÌT .2

13 fl

* O

o e

U CO

8. a

C te

S 2

I "^

ai m

S t-o-r 'f, 8

c>,

I s? ]? - j! (s-i ££

iig it

* 5 ".pi

• u * a ci)

>> £ ___

»O Rt

_ >> eu

S &

o 2 c S 25 *

"U fl o Ä ^ fO

O "*" "9 g O u a S 8 3. year",

■ S g a>

* 0

* ■ 5

o

T3 T3

ü i

S T3 <c o g

• O O C C3

O

0

a s

* H

/ -s o C- <v-> c - N / A .5 O

eu "S S 0" «

.2 "c o

where

W W

If

M

o * 0

c u 3

.2 * * 3 ö

9

646 688

to bring the temperature of the mixture to 43 ° C (119 ° F) or less. The mixture is emulsified by the addition of cold water with high speed stirring. After approximately 10 to 30 min, the speed of the agitator is reduced and the emulsion is diluted to the desired concentration.

In other emulsions and sizing compositions, the organic peroxide is dissolved in the hydrocarbon solvent with slight heating, but normally not above 37.8 ° C (100 ° F). A usual mixer is used for approximately 45 min and the solution obtained is generally clear after this time. The ether and ethanol type emulsifiers are then added, and the condensate type emulsifier is dissolved in hot water, and stirred for about 30 min until cooled. The mixture of organic peroxide and emulsifiers in the hydrocarbon solvent is subjected to stirring in the Eppenbach mixer, then the solution of the emulsifier of the propylene oxide / ethylene oxide type is slowly poured into mixing, until the phase reversal occurs. This inverted mixture

is then diluted with cold water to obtain the desired concentration of peroxide.

Table II gives the sizing compositions produced with several of the emulsions in Table I.

These sizing compositions were prepared by pouring approximately 9.51 (2.5 gallons) of cold water into a mixing tank, then adding acetic acid with stirring. The silane is then added slowly and stirred for about 30 min, until the hydrolysis of the silane is substantially complete. The lubricant, which is a partially acylated polyalkylene amine, is dissolved in hot water, diluted with cold water to a temperature of 37.8 ° C (100 ° F), and poured in the mixing tank. The emulsion which we had previously prepared is added in turn to the tank. Polyvinyl acetate, which will form a film, is dissolved in cold water and poured into the tank. The volume of the sizing solution is then brought to 381 (10 gallons).

Table II

Sizing solutions made with the emulsions of table I

Components

1

5

6

7

10

11

12

13

Emulsion

278 (7.3) *

5560 (7.4)

483 (12.8)

378 (10)

201.2 (5.3)

414 (5.5)

16.698 (7.7)

224.4 (5.9)

Acetic acid

4.2 (0.1)

-

8.4 (0.2)

6.3 (0.2)

4.2 (0.1)

10.5 (0.1)

422 (0.2)

5.3 (0.1)

Vinyltris (2-

methoxy-

ethoxy) silane

(A-172 from

Union

Carbide

Corp.)

106.4 (2.8)

2128 (2.8)

212.8 (5.6)

159.6 (4.2)

106.4 (2.8)

266 (3.5)

10.632 (4.9)

133 (3.5)

Lubricant for

poly fibers

alkylene-

imine partial

slightly acylated

(Emery 6717)

0.7 (0.02)

14 (0.02)

1.4 (0.04)

1.1 (0.03)

0.7 (0.02)

1.8 (0.02)

70.3 (0.03)

0.9 (0.02)

Poly acetate

vinyl (Natio

nal Starch

Resyn 25-

1031)

56 (1.5)

1120 (1.5)

112 (3.0)

84 (2.2)

-

98 (1.3)

3.920 (1.8)

49 (1.3)

Water

3340 (88.2)

66800 (88.3)

2,967 (78.4)

3,156 (83.4)

3,472.5 (91.7)

6778 (89.5)

184.708 (85.3)

3372 (89.1)

pH

-

-

3.95

-

3.9

4.1

4.0 ± 0.5

-

Content in

solids (%)

-

-

7.77

-

3.1

4.39

6.97

4.44

* Figures indicate grams; the figures in parentheses indicate percent by weight.

Table III presents the physical characteristics of several of the emulsions in Table I and the sizing compositions of 55

table II. These characteristics include the particle size of the emulsion and the sizing composition, as well as an assessment of the stability of the emulsion in the sizing composition over time. , T ,,,

v (Table on next page)

60

The preceding explanation described an emulsion of a solid organic peroxide which is insoluble or hardly soluble in water, peroxide which is dissolved in a hydrocarbon solvent with one or more emulsifiers so as to produce a stable emulsion which can be stored for as long as three months, which can be easily diluted, is safe and requires little care during preparation.

The organic peroxide can be chosen from the peroxides described above and the type of hydrocarbon solvent varies somewhat depending on the type of organic peroxide. For example, when the organic peroxide has a low aromatic character, the hydrocarbon solvent will have a kauri / butanol index of between about 10 and about 60. If the organic peroxide has a strong aromatic character, the hydrocarbon solvent will have a kauri / butanol of between approximately 40 and approximately 100. One or more emulsifiers can be used to obtain the emulsification, but it is preferred to take a mixture of three emulsifiers, one of which has an HLB index of between approximately 12 and approximately 20, the second an HLB index of between approximately 6 and approximately 12, and the third an intermediate HLB index of between approximately 9 and approximately 15.

The sizing composition contains the emulsion described above and other ingredients usually found in such

65

646 688 10

being in the form of fragments, threads, pieces of thread, rovings or tablecloths.

Such reinforced polymer products can be of the reinforced polyolefin type, such as for example polypropylene reinforced with glass fibers sized with the sizing composition containing the emulsion described above.

Other products based on reinforced polymers may contain other polyolefins, polyamides, for example nylon, or thermosetting polyesters, and still other similar products.

Table III

Particle size (| x)

1

6

7

9

10

11

12

13

Emulsion

1.59

1.25

0.97

0.99

Sizing solution

1.73

5.36

3.61

-

-

-

-

-

Initial stability

emulsion good very good good excellent good

-

ok (L-LY)

good (oly)

sizing solution good good good

-

good

-

ok (L-LY)

good (oly)

Storage stability

after:

24h

emulsion

-

very good (vl)

-

-

good ok (oly)

M-M-Y

good (oly)

sizing solution

-

very good

-

-

good ok (oly)

M-M-Y

good (oly)

48 h

emulsion

-

-

-

-

good ok (oly)

M-M-Y

good (oly)

sizing solution

-

-

-

good ok (oly)

M-M-Y

good (oly)

72 h

emulsion good good (vl)

OK)

-

-

ok (oly)

M-M-Y

good (oly)

sizing solution good light separation okffl

-

-

OK

M-M-Y

good (oly)

redispersible

4d

emulsion

-

-

.—

-

-

ok (oly)

M-M-Y

good (oly)

sizing solution

H A

-

-

-

-

-

ok (oly)

M-M-Y

good (oly)

/ d

emulsion

.

ok, oily

H-H-Y

good (oly)

sizing solution

-

-

ok few particles good (oly)

where Y = sedimentation or dispersible separation; O = no separation; H = strong sedimentation; M = average sedimentation; L = slight sedimentation.

sizing solutions, such as, for example, coupling agents, film-forming agents, lubricants and the like.

The process for preparing the emulsion comprises dissolving the organic peroxide in the hydrocarbon solvent and forming the emulsion. Sized glass fibers which are made of glass of any type, but preferably made of glass of type C or 621 or of modifications thereof with low boron content or / can be used for the reinforcement of polymer articles. and fluorine, these fibers

R

Claims (19)

646 688 2 1. Aqueous emulsion having good stability and easily diluted, the particles of which have a size of 1.5 n or less, these being regularly distributed, emulsion constituted by an organic peroxide which is solid at about 20 ° C. and which has a limited solubility or which is insoluble in water, this emulsion being characterized in that it comprises: a) from 1 to 70% by weight of a solid organic peroxide having a limited solubility or being insoluble in water, chosen from the group formed by hydroperoxides, a-oxy- and a-peroxyhydro-peroxides, dialkyl peroxides , aldehyde and ketone peroxides, diacyl peroxides, peroxyesters, peracids, peroxydicarbonates, nonoperoxycarbonates and percetals; b) from 1 to 70% by weight of a hydrocarbon solvent having a kauri / butanol index of between 10 and 60 when the peroxide is essentially of aliphatic nature, or then between 40 and 100 when the organic peroxide is essentially of aromatic nature ; c) from 1 to 15% by weight of at least one nonionic emulsifier having an HLB index of between 9 and 20, and d) at least 25% by weight of water. 2. Aqueous emulsion according to claim 1, characterized in that the emulsifier comprises: i) a nonionic emulsifier having an HLB index of between 12 and 20; ii) a nonionic emulsifier having an HLB number between 6 and 12, and iii) a nonionic emulsifier having an HLB number between 9 and 15, these nonionic emulsifiers being chosen from the group formed by polyalkylene glycol ethers, polyether alkylaryl alcohols, the condensation products of polyoxypropylenes and polyoxyethylenes, and ethoxylated alcohols of phen-oxypolyethoxyethanols, ethoxylated fatty acids, fatty acid esters and oils; fatty acids, glycolic esters, mono-glycerides and their derivatives, sorbite derivatives and sucrose esters and their derivatives, the emulsifier of each different group of HLB i, ii and iii being taken in an amount such that the HLB index of the total system is in the range between 9 and 20. 3. Aqueous emulsion according to claim 1, characterized in that the organic peroxide has a half-life exceeding 60 h at 100 ° C (212 ° F) and 20 min at 149 ° C (300 ° F). 4. Aqueous emulsion according to claim 1, characterized in that the organic peroxide is a-, a'-bis- (t-butylperoxy) diisopropylbenzene. 5. Aqueous emulsion according to claim 4, characterized in that the hydrocarbon solvent has a kauri / butanol index located around 92 to 93. 6. Aqueous emulsion according to claim 5, characterized in that the ratio of peroxide to the solvent is at least 1 / 0.4. 7. Aqueous emulsion according to claim 2, characterized in that the three emulsifiers are present in equal amounts. 8. An aqueous emulsion according to claim 1, in the form of a sizing composition for glass fibers in a concentration sufficient to provide an amount of active peroxide in the treatment solution which is between 0.1 and 6% by by weight, this solution further comprising between 0.5 and 10% by weight of a coupling agent and between 70 and 99% by weight of water. 9. An aqueous emulsion according to claim 8, in the form of a sizing composition containing between 0.1 and 6% by weight of a lubricant. 10. An aqueous emulsion according to claim 3, comprising: a) from 1 to 70% by weight of an organic peroxide having the following formula: (R-O — O—) x — R ' wherein R is an tertiary alkyl, aroyl or acyl group with or without a phenyl group bound to its tertiary carbon atom; x is a number which is 1,2 or 3, and R 'is identical to R or else is an organic fragment of formula: R "R" I I C — R17 — C I I R '"R" " in which RIV is chosen from phenyl, alkylphenyl, alkyne or alkyl groups of formula (CH2 - CH2) „- where n is 1, 2 or 3; R "and R '" are chosen from a hydrogen atom or one of the R — O — O—, alkyl, cycloalkyl, aralkyl or aryl groups and, when RIV is a phenyl group, either R "or R'" is a hydrocarbon radical chosen from phenyl, aryl or alkyl groups containing more than 7 carbon atoms; b) from 10 to 55% by weight of a hydrocarbon solvent having a kauri / butanol index of between approximately 10 and approximately 60 when the organic peroxide contains radicals R, R ', R ", R" "or RIV which are aliphatic or of low aromatic character; or this index is between 40 and 100 when the radicals R, R ', R ", R'" and RIV have a strongly aromatic character; c) from 1 to 15% by weight of one or more emulsifiers chosen from: i) one or more polyalkylene glycol ethers; ii) one or more alkylaryl polyether alcohols; iii) one or more products of the condensation of polyoxypropylene and of polyoxyethylene, or iv) one or more phenoxypolyethoxyethanols which give the emulsifier or emulsifiers an HLB index of between 9 and 20, and d) at least 25% by weight of water. 11. An aqueous emulsion according to claim 8, characterized in that the coupling agent is vinyltris- (P-methoxyethoxy) -silane. 12. An aqueous emulsion according to claim 9, characterized in that the lubricant is a cationic amide of a fatty acid dissolved in an acid. 13. An aqueous emulsion according to claim 9, in the form of a sizing composition which contains between 0.5 and 12% by weight of a film-forming agent. 14. Aqueous emulsion according to claim 13, characterized in that the film-forming agent is a vinyl acetate copolymer. 15. Glass fibers sized by the emulsion in the form of a sizing composition according to one of claims 8, 9 and 13. 16. Process for the preparation of an aqueous emulsion of a, a'-bis- (t-butylperoxy) diisopropylbenzene according to claim 1, characterized by: a) the solubilization of ra, a'-bis- (t-butylperoxy) diisopropylben-zene in a hydrocarbon solvent having a kauri / butanol index between 70 and 100, this according to a ratio of peroxide to solvent of at least 1 / 0.4; b) the addition of 1 to 15% by weight of the emulsion, of one or more emulsifiers chosen from: i) one or more polyalkylene glycol ethers; ii) one or more alkylaryl polyether alcohols; iii) one or more condensates of polyoxypropylenepolyoxyethylenene, or iv) one or more phenoxypolyethoxyethanols, or from any mixture of these in a ratio which gives an HLB index of 9 to 20 in total, and c) the addition of water in an amount of at least 35% by weight of the emulsion to emulsify the peroxide, the solvent and the emulsifier (s) to form an oil-in-water emulsion. 17. Method according to claim 16, characterized in that the emulsifier or emulsifiers consist of a mixture of three emulsifiers comprising: a) from 0.1 to 5% by weight of an emulsion of trimethylnonyl ether of polyethanolethylene glycol having an HLB index of 11.7; 5 10 15 20 25 30 35 40 45 50 55 60 65 3 646 688 b) from 0.1 to 5% by weight of a nonylphenoxypoly- (ethylenoxy) ethanol emulsion having an HLB number of 13, and c) from 0.1 to 5% by weight of an emulsion of a product of condensation of ethylene oxide with a hydrophobic base which is formed by the condensation of propylene oxide with propylene glycol, having an HLB index of 17.0. 18. The method of claim 17, characterized in that the trimethylnonyl ether of polyethylene glycol, nonylphenoxy-poly (ethylenoxy) ethanol and the first portion of the total amount of the condensation product of ethylene oxide are added separately or at the same time to the peroxide / solvent mixture, and the remaining portion of the ethylene oxide condensation product is first mixed with water in a proportion of about 50/50, then is added to the mixed. 19. The method of claim 17, characterized in that the hydrocarbon solvent has a kauri / butanol index of 92 to 93.