MXPA01001594A - Peroxides, their preparation process and use - Google Patents

Abstract

The present invention relates to a new class of peroxides and to a process for the preparation of these peroxides having general formula (I), wherein n=1 or 2, R1, R2, R4, R5 and R6 are independently selected from the group comprising hydrogen, C1-C20 alkyl, C3-C20 cycloalkyl, C6-C20 aryl, C7-C20 aralkyl, and C7-C20 alkaryl, or R1 and R2 form a C3-C12 cycloalkyl group, which groups may include linear or branched alkyl moieties;and each of R1, R2, R4, R5 and R6 may optionally be substituted with one or more groups selected from hydroxy, alkoxy, linear or branched alkyl, aryloxy, halogen, ester, carboxy, nitrile, and amido, and R1 and R2 may form a ring, and R3 is independently selected from the group comprising C1-C20 alkyl, C3-C20 cycloalkyl, C6-C20 aryl, C7-C20 aralkyl, and C7-C20 alkaryl, which groups may include linear or branched alkyl moieties;and R3 may optionally be substituted with one or more groups selected from hydroxy, alkoxy, linear or branched alkyl, aryloxy, halogen, ester, carboxy, nitrile, and amido, and any pair of the optionally substituted R3, R4, R5, and R6 may form a ring, comprising the reaction of the corresponding ketone peroxide with general formula (II), wherein n, R1, and R2 have the identified meaning, with an alkyl vinyl ether with general formula (IIIa) or with an acetal with general formula (IIIb), wherein R3, R4, R5, and R6 have the identified meaning, in the presence of a catalyst, to the use of these peroxides as polymerization initiator, curing for unsaturated polyester, and/or modifying agent, and to formulations comprising these peroxides and a carrier or diluent.

Description

PEROXIDES, ITS PROCEDURE FOR PREPARATION AND ITS USE DESCRIPTIVE MEMORY The present invention relates to particular peroxides, their preparation processes and their uses. More particularly, the present invention relates to processes for the preparation of these peroxides, which can be obtained by the reaction of a corresponding ketone peroxide and an alkyl vinyl ether or an acetal. Finally, the present invention relates to the use of these peroxides as polymerization initiators, curing agents of unsaturated polyesters, and modifying agents, and to formulations comprising these peroxides. In US-A-3, 576,826 the peroxyether compounds and their preparation are described from alpha-substituted vinyl ethers. In the case of the peroxyethers (v) the adjacent peroxide groups can be separated by an unidentified aliphatic or cycloaliphatic group. It is the object of the present invention to provide a new class of peroxides which are useful as polymerization initiators, unsaturated polyester-curing agents, and modifying agents. Another object of the present invention is to provide peroxides with high reactivity in view of the compounds of US-A-3,576,826.

Another object of the invention is to provide peroxides with better storage stability at room temperature in view of the compounds of US-A-3,576,826. Accordingly, the present invention provides a process for the preparation of peroxides having the general formula (I), wherein n = 1 or 2, R-i, R2, R4, R5, and R6 are independently selected from the group consisting of hydrogen, C1-C20 alkyl. C3-C20 cycloalkyl, C8-C20 aryl, C7-C20 aralkonium, and C7-C20 alkaryl, or Ri and R2 forms of the C3-C-? 2 cycloalkyl group, whose groups may include linear alkyl portions or branched; and each of Ri, R2, R, R5, and R6 can be optionally substituted with one or more groups selected from hydroxy, alkoxy, linear or branched alkyl, aryloxy, halogen, ester, carboxy, nitrile, and amido, and R10 and R2 can form a ring; and R3 is selected independently from the group comprising CrC20 alkyl, C3-C20 cycloalkyl, C8-C20 aryl, C7-C20 aralkyl, and C7-C2al alkaryl, which groups may include straight or branched alkyl portions; and R3 may be optionally substituted with one or more groups selected from hydroxy, alkoxy, linear or branched alkyl, aryloxy, halogen, ester, carboxy, nitrile, and amido, and any pair of the optionally substituted R3, R4, R5, and R6 can form a ring, comprising the reaction of the corresponding acetone peroxide with the general formula (II) wherein n, R-i, and R2 have the identified meaning, with an alkylvinyl ether with the general formula (Illa) or with an acetal with the general formula (IIIb).

H R, -Rs (Illa) R, -O-C-C-R5 (lllb) R "Re R, Re wherein R3, R4, R5 and R6 have the identified meaning, in the presence of a catalyst.

The ketone peroxide of the formula II can be a so-called T4-ketone peroxide (n = 1) and / or a so-called T3-ketone peroxide (n = 2). T-ketone peroxide having the general formula lia which is suitable for the reaction with the aforementioned alkylvinyl ethers of the formula Illa or with the aforementioned acetal of the formula lllb which are formed by the following ketones: acetone, acetophenone, methyl-n-amylketone, ethylbutyl ketone, ethylpropyl ketone, methyl isoamyl ketone, methylheptyl ketone , methyl ethyl ketone, ethylamyl ketone, diethyl ketone, dipropyl ketone, ethylethyl ketone, methyl isobutyl ketone, methyl isopropyl ketone, methyl propyl ketone, methyl n-butyl ketone, methyl t-butyl ketone, methylcyclohexanone, isobutylketone ketone, diisobutyl ketone, methoxyacetone, cyclohexanone, isobutylheptylacetone, diisobutylacetone, methoxyacetone, cyclohexanone, 3,3 , 5-trimethyl-cyclohexanone, N-butylevulinate, ethylacetoacetate, methylbenzyl ketone, phenylethyl ketone, methylchloromethyl ketone, methyl bromomethyl ketone, and other ketones having the appropriate Ri and R2 groups corresponding to the peroxides of formula II which may be employed, as well as mixtures thereof. two or more different ketones. The ketone-T3 peroxide having the general formula IIb which are suitable for the reaction with said alkyl vinyl ether of the formula Illa or with said acetal IIIb are those which are derivatives of the same group of ketones as mentioned for the peroxides of T-acetone. Preferably, the ketone peroxide is formed or derived from methyl ethyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, acetone, cyclohexanone and / or 3,3,5-trimethylcyclohexanone. Methyl isobutyl ketone and methyl ethyl ketone are most preferred. The alkyl vinyl ethers of the formula Illa (in which R is hydrogen) can be illustrated as follows: vinyl 2,2-bis (vinylmethyl) butyl ether, allyl 2,3-epoxypropyl ether, n-propylvinyl ether, 1-ethoxy- 4-methyl-1-nonene, tert.amilvinyl ether, 2,2-bis (4-vinyloxyphenyl) propane, hexadecylvinyl ether, methylvinyl ether, 4-methylhexyl vinyl ether, 2- (2-ethoxyethoxy) ethyl vinyl ether, ether 2 -methoxyethylvinyl, 2-vinyloxyethanol, 4-methyl-1-decenylvinyl ether, benzyl-1-methylvinyl ether, butanedioldivinyl ether, tertbutylvinyl ether, isobutylvinyl ether, cyclohexanedimethanol di-vinyl ether, cyclohexylvinyl ether, ethylene glycol dimethyl ether, 1-ethoxy-4- (1 -ethoxy vinyl) -3,3,5,5-tetramethylcyclohexane, allyl vinyl ether, isopropyl vinyl ether, ethyl vinyl ether, tetraethylene glycolivinyl ether, 1-methoxy-1-buten-3-yne, heptyl vinyl ether, 4- (1-ethoxyvinyl) l) -3,3,5,5-tetramethylcyclohexanone, 2-butoxyethyl vinyl ether, ether allylethyl, divinyl ether, 1,3-divinyloxy-2,2-dimethylpropane, 4-vinyloxybutanol, diethylene glycol divinyl ether, 4- (vinylmethyl) cyclohexylmethanol, isopentylvinyl ether, diethylene glycol monovinyl ether, n-butylvinyl ether, 1,4-bis (2-vinyloxyethyl) benzene, divinyl hexanediol ether, 1-methoxy-1,3-butadiene, decylvinyl ether, 4- (allyloxymethyl) -1, 3-dioxolan-2-one, 1,1-diethylpropylvinyl ether, 2 -methoxyvinylbenzene, octylvinyl ether, bis (vinyloxy) methane, 1,4-dimethoxy-1,3-butadiene, triethylene glycolivinyl ether, pentylvinyl ether, octadecylvinyl ether, triethylene glycol methyl vinyl ether, 2,3-epoxypropylvinyl ether, dodecylvinyl ether, 1, 1-bis (vinyloxy) butane, hexylvinyl ether, 6-vinyloxyhexanol, (z) -1-methoxy-1-buten-3-yne, phenyl vinyl ether, 2-ethylhexyl vinyl ether, poly-THF-divinyl ether, ether pluriol-E -200-divinyl, trimethyl-propane-di-vinyl ether, aminopropylvinyl ether, 2-diethylaminoethyl vinyl ether Ixil, ethylpropenyl ether. Examples of alkylvinyl ethers of the formula Illa in which it is an alkyl are the following: 2-methoxy-2-butene, 1, 1, 3-trimethoxypropene, 2,3-dimethoxy-1,3-butanediene, 2-methoxypropene, 2-ethoxy propene, 2-isobutoxypropene, 2-ethoxy-2-butene, 2-isobutoxy-2-propene. Examples of tri-substituted and cyclic alkylvinyl ethers are 1-methoxy-2-methylcyclohexane and 2-methoxy-2-methyl-2-butane. Examples of the alkylvinyl ethers are 2-methyl-2,3-dihydrofuran, 2,3-dihydrofuran, 2-methyl-3,4-dihydropyran, 3,4-dihydropyran, 1-methoxycyclohexane. Preferred are ethyl vinyl ether, isobutyl vinyl ether, propyl vinyl ether, and butyl vinyl ether. More preferred is isobutylvinyl ether. Examples of the acetals of the formula IIIb are 2,2-dimethoxypropane, 2,2-diethoxypropane (with R 4 which is an alkyl) or, 1,1-dimethoxybutane, 2-propyl-1,3-dioxolane, 1, 1- dimethoxyethane, 1, 1-diethoxyethane, 1, 1-diethoxypropane, and 1,1-dimethoxycyclohexane (with R which is a hydrogen).

It is preferred to 1,1-dimethoxyethane. The reaction between the ketone peroxide of the formula II and the alkyl vinyl ether of the formula IIIa or the acetal of the formula IIIb is carried out under conventional conditions for this type of addition reactions. The temperature is generally in the range of 0-50 ° C and preferably between -25 ° C. The reaction is carried out in the presence of an acid catalyst.

The amount of acid catalyst is generally 0.01 -30 g / mol and preferably 0.1-15 g / mol of ketone peroxide. The acid catalyst for the process is a conventional acid catalyst such as the C 1 -C alkane or an arylsulfonic acid, a halogenated C 1 -C 10 alkanesulfonic acid or a mixture of one or more of these compounds. Preferred catalysts for use are, but are not limited to, p-toluenesulfonic acid and methanesulfonic acid. Although this reaction can be carried out without a solvent, it is preferred to carry out the reaction in a conventional homogeneous solvent system. Suitable solvents are generally hydrocarbon solvents, esters, aromatic hydrocarbon solvents, aralkyl solvents, paraffinic oils, white oils, and silicone oils, as well as mixtures thereof. The use of solvents includes, but is not limited to, benzene, xylene, toluene, mesitylene, hexane, hydrogenated alkane oligomers such as Isopar products (eg Exxon), Shellsol® products (eg Shell), pentane, heptane, decane, sododecane, decalin, dibutyl phthalate, dioctyl adipate, dioctyl terephthalate, 2,2,4-tri-methyl-1,3-pentanediol diisobutyrate, butylbenzoate, and the like. Among the paraffinic oils used as solvents is paraffinic diesel oil. Other oils include white oils, epoxidized soybean oils, and silicone oils that are also useful in the present invention. Preferably, R4 is a hydrogen because the peroxide shows better storage stability at room temperature and is less sensitive to hydrolysis. More preferably, R and R5 and / or R6 are hydrogens. Generally, the process for preparing the peroxide is carried out so that an equivalent amount of the alkyl vinyl ether of the formula Illa or the acetal of the formula IIIb is in the range of 1-5 equivalents. Preferably, the range is from 1.5 to 3.0 equivalent, more preferably from 2.0 to 2.5 equivalents. These equivalent numbers are selected so that the chemical yield is optimal. It was noted that in the preparation process the ketone peroxide used can be a pure ketone peroxide (T4) of the formula lal or a ketone peroxide (T3) of the formula! Lb. For specific properties it may be advisable to use a mixture of ketone peroxide T4 and T3. For example, ketone peroxide T3 or T4 may comprise 5% -30% ie 5% -25% and 10% -15%, of the other ketone peroxide. In addition, the invention relates to the peroxides of the formula I where R1? R2, R3, R4, R5 and R6 have an identified meaning and which are obtained with the preparation process described above. The peroxides according to the present invention produced with the preparation process according to the present invention can be used as initiators of the production of polymers and in particular for the preparation of (poly) vinyl chloride, acrylic (co) polymers, polystyrene, polyethylene, for curing unsaturated polyester resins, and for polymeric modification (such as the grafting of monomers). In the present invention, the polymerization was conducted by any conventional method, with the exception that a specified radical polymerization initiator (or composition) was used. The polymerization process can be carried out in the usual manner, for example in a mass, suspension, emulsion or solution. In the case of the production of ethylene (co) polymers, the reaction is usually carried out under high pressure, ie of about 1000 to 3500 bars. The amount of initiator, which varies depending on the polymerization temperature, the ability to remove heat from the polymerization, and, where applicable, the type of monomer to be used, and the applied pressure, must be an effective amount to achieve polymerization. Usually, 0.001-25% by weight of peroxide is employed, based on the weight of the (co) polymer. Preferably 0.001-20% by weight peroxide is used and more preferably 0.001-15% by weight. For most reactions within the present invention, the polymerization temperature is usually 30 ° to 350 ° C, preferably 40 ° to 300 ° C. In general, if the temperature is below 30 ° C, the polymerization time becomes too long. However, when this exceeds 350 ° C, the radical polymerization initiator is spent in the initial stage of the polymerization, making it difficult to achieve high conversion. In order to reduce the amount of non-reactive monomer, therefore, it is possible to conduct the polymerization using a temperature profile, that is, perform the initial polymerization below 100 ° C and then raise the temperature above 100 ° C. C to complete the polymerization. These variations are completely known by the experts, who will have no difficulty in selecting the conditions of choice of the reaction, depending on the particular polymerization process and the specific radical polymerization initiator to be used. The monomers suitable for polymerization using the peroxides according to the present invention are ethylenically unsaturated or olefinic monomers, for example substituted or unsubstituted vinyl aromatic monomers including styrene, alpha-methylstyrene, p-methylstyrene, and halogenated styrenes; divinylbenzene; ethylene; ethylenically unsaturated carboxylic acids and derivatives thereof, such as (meth) acrylic acids, (meth) acrylic esters, butylacrylate, hydroxyethyl (meth) acrylate, methyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and glycyl methacrylates; ethylenically unsaturated nitriles and amides, such as acrylonitrile, methacrylonitrile, and acrylamide; unsubstituted or substituted ethylenically unsaturated monomers, such as butadiene, isoprene, and chloroprene; vinyl esters such as vinyl acetate and vinyl propionate; ethylenically unsaturated dicarboxylic acids and their derivatives including mono- and diesters, anhydrides, and imides, such as maleic anhydride, citraconic anhydride, citraconic acid, itaconic acid, nadic anhydride, maleic acid, fumaric acid, aryl, alkyl, and aralkyl cyraconimides and maleimides; vinyl halides, such as vinyl chloride and vinylidene chloride; vinyl ethers, such as methylvinyl ether and N-butylvinyl ether; olefins, such as isobutene and 4-methylpentene; allyl compounds, such as (di) allyl esters, for example diallyl phthalates, (di) allyl carbonates, and detriallyl (iso) cyanurate. During the (co) polymerization, the formulations may also contain the usual additives and fillers. As an example of such additives, there may be mentioned: stabilizers such as oxidative, thermal or ultraviolet degradation inhibitors, lubricants, dilation oils, pH controlling substances, such as calcium carbonate, release agents, dyes, fillers reinforcing or not reinforcers such as silica, clay, gypsum, carbon black, and fibrous materials, such as fiberglass, plasticizers, diluents, chain transfer agents, accelerators, and other types of peroxides. These additives can be used in the usual amounts. Finally, the polymerization process of the present invention can be used to introduce functional groups into (co) polymers. This can be done by using peroxide that contains one or more functional groups attached to it. These functional groups remain intact in the free radicals formed by the peroxides and are thus introduced into the (co) polymer. Conditions and equipment for conventional polymerization can be used to achieve the objective of the present invention. The peroxides according to the invention which can be used as binding agents for the unsaturated polyesters and unsaturated polyester resins according to the present invention usually include an unsaturated polyester and one or more ethylenically unsaturated monomers. Suitable polymerizable monomers include styrene, alpha-methylstyrene, p-methylstyrene, chlorostyrenes, bromostyrenes, vinylbenzyl chloride, divinylbenzene, diallyl maleate, dibutyl fumarate, triallyl phosphate, triallyl cyanurate, diallyl phthalate, dialkyl fumarate, methyl (meth) acrylate, -butyl (meth) acrylate, ethyl acrylate, and mixtures thereof which are copolymerizable with unsaturated polyesters. The unsaturated polyesters are, for example, polyesters since they are obtained by the styration of at least one ethylenically unsaturated di-copolycarboxylic acid, anhydride or acid halide, such as maleic acid, fumaric acid, glutaconic acid, itaconic acid, mesaconic acid , citraconic acid, allylmalonic acid, tetrahydrophthalic acid, and others, with saturated and unsaturated diols or polyols, such as ethylene glycol, diethylene glycol, triethylene glycol, 1,2- and 1,3-propanediols, 1, 2, 1, 3 -, and 1,4-butanediols, 2,2-dimethyl-1,3-propanediols, 2-hydroxymethyl-2-methyl-1,3-propanediol, 2-buten-1,4-diol, -butin-1,4-diol, 2,4,4-trimethyl-1,3-pentanediol, glycerol, pentaerythritol, mannitol and others. The di- or polycarboxylic acids can be partially replaced by saturated di- or polycarboxylic acids, such as adipic acid, succinic acid, and others, and / or by aromatic di- or polycarboxylic acids, such as phthalic acid, trimellitic acid, pyromellitic acid , isophthalic acid, and terephthalic acid. The acids used can be substituted with groups such as halogen. Suitable halogenated acids include, for example, tetrachlorophthalic acid and tetrabromophthalic acid. The peroxides of the present invention are suitable for use in the modification of polymers such as degradation, crosslinking or grafting. More particularly, these peroxides can be used in processes for grafting monomers into polymers such as polyolefins, and elastomers, and for functionalizing polyolefins in the case of peroxides containing functional groups of the present invention. In general, the peroxide can be contacted with the (co) polymer in various ways, depending on the particular object of the modification process. The polymeric material can be in a solid state, in the molten state, in the form of a solution in the case of an elastomer, in a plastic state or in any physical form including finely divided particles (flakes), pills, film, foil, in the molten material, in solution, and the like. The polymers can also be in liquid form, ie liquid gums.

In general, any (co) polymer comprising extractable hydrogen atoms, in particular polyolefins, can be modified by the present process. The amount of peroxide used in the modification process of the present invention should be an amount effective to achieve a significant modification of the (co) polymer when treated with a (co) polymer, more particularly 0.001-150.0% by weight of peroxide based on the weight of the (co) polymer, it should be used. More preferably, 0.005-10.0% by weight percent is employed. More preferably still, an amount of 0.01-5.0% by weight is employed. Peroxides can be prepared, transported, stored, and applied in the form of powders, granules, pellets, concentrates, flakes, slabs, paste, and solid and liquid master batches. These formulations can take the form of a dispersion, such as a suspension or an emulsion. These can be phlegmatized if necessary, depending on the particular peroxide and its concentration in the formulation. Which of these forms is preferred depends in part on the application for which it will be used and partly on the manner in which it will be mixed. Also, safety considerations may play a role in the degree of phlegmatization that can be incorporated into certain compositions to ensure safe handling. The formulations of the present invention are transportable, storage stable, and contain 1.0-90% by weight of one or more peroxides according to the present invention. Transportable means that the formulation of the present invention has passed the pressure vessel test (PVT). Stable storage means that the formulations of the present invention are both chemically and physically stable for a reasonable storage period under standard conditions. Preferred formulations according to the present invention contain 10-90% by weight of one or more of the peroxides, more preferably these formulations contain 30-90% by weight of the peroxides, and even more preferably these formulations contain 40-80% in weight of the peroxides. The formulations of the present invention can be liquid, solid or pastes, depending on the melting point of the peroxide and the diluent employed. Liquid formulations can be made using liquid phlegmatizers for ketone peroxide, liquid plasticizers, organic peroxides, and mixtures thereof as diluents. The liquid component is generally present in an amount of 1-88% by weight of the composition, preferably 10-90% by weight, more preferably 30-90% by weight, and more preferably 40-80% by weight of the liquid formulation which consists of liquid diluents. It should be noted that certain phlegmatizers may not be suitable for use with all peroxides of the present invention, more particularly, in order to obtain a safe composition, the phlegmatizer must have a certain minimum flash point and a boiling point relative to the decomposition temperature of the peroxide in such a way that the phlegmatizer can not boil leaving behind a concentrated and insecure ketone peroxide composition. Thus, the low boiling of the phlegmatizers mentioned below may only be useful, for example, with particular substituted peroxides of the present invention having a low decomposition temperature. In liquid formulations a liquid carrier or diluent is used. Preferably, this vehicle or diluent is a solvent. Examples of the solvents are those given above for the preparation of various peroxides. Solid carrier materials are used in the solid and / or paste formulations of the present invention. Examples of such solid carriers are solids with low melting point, such as dicloexil phthalate, dimethyl fumarate, dimethyl isophthalate, triphenyl phosphate, glyceryl tribenzoate, trimethyl oletantribenzoate, dicycloxy terephthalate, paraffin waxes, dicyclohexyl isophthalate, polymers and inorganic supports. Inorganic supports include materials such as evaporated silica, precipitated silica, hydrophobic silica, chalk, white from Spain, treated clays for surfaces such as silane treated clay, calcined clay and talc. Polymers useful in the formulations of the present invention include polyethylene, polypropylene, ethylene / propylene copolymers, terpolymers of ethylene / propylene / diene monomer, chlorosulfonated polyethylene, chlorinated polyethylene, polybutylene, polyisobutylene, ethylene / vinyl acetate copolymer, polyisoprene, polybutadiene, butadiene / styrene copolymers, natural rubber, polyacrylate gum, butadiene / acrylonitrile copolymers, acrylonitrile / butadiene / styrene terpolymers, silicone gums, polyurethanes, polysulfides, solid paraffins, and prolicaprolactone. The formulations stable to storage must be stable both physically and chemically. By physically stable formulations are meant those formulations that do not suffer from a significant phase separation once they are stored. The physical stability of the present formulations can, in some cases, be improved by the addition of one or more thixotropic agents selected from cellulose esters, hydrogenated castor oil; and evaporated silica. Examples of said cellulose esters are the reaction products of cellulose and acidic compounds selected from, for example, acetic acid, propionic acid, butyric acid, phthalic acid, trirnethyl acid, and mixtures thereof. By chemically stable formulations are meant those formulations that do not lose a significant amount of their active oxygen content once they are stored. The chemical stability of the present formulations can, in some cases, be improved by the addition of one or more known additives including sequestering agents such as dipicolinic acid and / or antioxidants such as phenol 2,6-di (t-butyl) -4-methyl and para-nonyl phenol.

The formulations of the present invention may also contain other optional additives as long as they do not have a significant adverse effect on the transportability and / or storage stability of the formulations. As examples of said additives, mention may be made of: anti-coagulation agents, free-flowing agents, antiozonants, antioxidants, anti-degradants, UV stabilizers, coagents, fungicides, antistatics, pigments, dyes, coupling agents, dispersing aids, dispersing agents, lubricants, processed oils. , mold release agents. These additives can be used in their usual amounts. The peroxides according to the invention can also be used as a dispersion, preferably in the polar medium. The medium in which the initiator according to the invention is dispersed should be inert towards the initiator and so polar that the initiator will hardly dissolve in it. The initiator is preferably dispersed in water or in alcohol. More preferably in a dispersion in water. Said medium is easily removed in comparison with any remnant, for example after modification of the (co) polymer if desired. Therefore, the use of water or alcohols is expected to be less profitable and have other drawbacks than the use of organic diluents such as toluene and xylene, which have been common up to now. As any expert knows, the use of other adjuvants in the dispersion of the initiators may be advisable or even essential in order to ensure that the chemical dispersion and / or the physical stability continue for a long period. For example, if the storage temperature of the dispersion initiator is less than the freezing point of the medium in which the initiator is dispersed, an appropriate freezing point depression agent may be added to counteract the freezing. Also, a wide range of substances can be used to alter the rheology of the formulation. At this point one or more surface active materials and one or more thickeners are generally used. If desired, other additives can be incorporated into the formulation. As examples of such additives there may be mentioned pH buffers, chemical stabilizers which counteract the premature decomposition of the initiator, and anti-aging compositions which counteract the growth of the size of the particles in the dispersion. The following examples illustrate the process for preparing the peroxides according to the present invention and their applications.

EXAMPLE 1 Preparation of a mixture of 2,2, -bis (1- (1-metiipropoxy) ethylperoxy) butane and b-sf1-methyl-1- (2- (2-methylpropoxy) ethylperoxy) propyl1 peroxide To 25 g of a stirred solution of methyl ethyl ketone peroxide containing 27.82% by weight of acetone peroxide T4 2,2-bis (hydroperoxy) butane and 14.4% by weight of T3 peroxide of bis (1-hydroperoxy-methylpropyl) 0.86 g of p-toluenesulfonic acid monohydrate was added to dimethyl phthalate. After 18.3 g of isobutylvinyl ether were added in 16 min, the reaction temperature was maintained at 20 ° C by cooling with an ice-water bath. The mixture was stirred for 2 min at 20 ° C, washed with bicarbonate solution, and dried over magnesium sulfate, yielding 41.6 g of product with an active oxygen content of 6.33% (chemical yield: 90 %). The following table 1 shows the results of the preparation of other peroxides according to the invention (R2 = methyl, R4, R5, and Re = H).

TABLE 1 EXAMPLE 2 Preparation of a mixture of 2,2-bis (1-methoxy-1-methylethylperoxy) -4-methylpentane and bis (1- (1-methoxy-1-methylethylperoxy) -1,3-dimethylbutyl) peroxide To 50 g of a stirring solution of methyl isobutyl ketone peroxide containing 7.89% by weight of dihydroperoxy-1,3-dimethylbutane and 36.84% by weight of bis (1-hydroperoxy-1) peroxide, 3-dimethylbutyl) in pentadecane was added 0.60 g of acetic acid. Then 13.73 g of 2-methoxypropene was added in 10 min, the reaction temperature was maintained at 20 ° C by cooling with an ice-water bath. The mixture was stirred for 30 min and 1.20 g of acetic acid was added. The mixture was allowed to stand overnight, obtaining a yield of 65 g of product with an active oxygen content of 6.15%. Chemical yield: 97%.

EXAMPLE 3 Preparation of 1,1-bis (1-isobutoxyethylperoxy) cyclohexane To 30 g of a stirring solution of 1,1-dihydroperoxycyclohexane in ethyl acetate was added 0.4 g of sulfonic acid p-toluene. Then 19.6 g of isobutylvinyl ether were added in 10 min, the reaction temperature was maintained at 20 ° C by cooling with an ice-water bath. The mixture was stirred for 60 min. The mixture was washed with a sodium bicarbonate solution and dried over MgSO 4. The yield obtained was 35 g of product with an active oxygen content of 6.75%. Chemical yield: 67%.

EXAMPLE 4 Preparation of 2,2-bis (1-ethoxypropylperoxy) -4-methyl pentane To 5 g of a stirring solution of methyl isobutyl ketone peroxide containing 35.7% by weight of bis (1-hydroperoxy-1,3-dimethylbutyl) peroxide in isododecane was added 0.05 g of p-toluenesulfonic acid. Then 1.8 g of ethylpropenyl ether were added in 10 min, the reaction temperature was maintained at 20 ° C by cooling with an ice-water bath. The mixture was stirred for 20 min at 15 ° C. The mixture was washed with bicarbonate solution and dried over magnesium sulfate, obtaining a yield of 5.8 g of product with an active oxygen content of 5.12%. Chemical yield: 91%.

EXAMPLE 5 Preparation of a mixture of 2,2-di (1-methoxybutylperoxy) butane and di (1- (1-methoxybutylperoxy) 1-methylpropyl peroxide) To 25 g of a stirred solution of methylethyl acetone peroxide, containing 27.82% by weight of 2,2-bis (hydroperoxy) butane and 14.4% by weight of bis (1-hydroperoxy-1-methylpropyl) peroxide in dimethylphthalate 0.86 g of p-toluene sulphonic acid monohydrate was added. Then 21.8 g of 1,1-dimethoxybutane were added in 16 min, maintaining the reaction temperature at 20 ° C by cooling with an ice-water bath. The mixture was stirred for a further 20 min at 20 ° C, washed with bicarbonate solution, and dried over magnesium sulfate, yielding a yield of 35.2 g of product with an active oxygen content of 6.68%. (chemical yield: 90%).

EXAMPLE 6 Curing of unsaturated polyesters The curing capacity of the peroxides as curing agents for unsaturated polyesters was determined and compared with the tertiary butylperoxy-2-ethyl hexanoate. A time-temperature curve at 100 ° C was measured in compounds containing 100 parts of polyester resin, 150 parts of sand as a filler, and 1 part of peroxide. This was carried out according to the method outlined by the Society of Plastic Institute. 25 g of the compounds were sprinkled into test tubes and a thermocoupler was placed through the content in the center of the tube. The glass tube was placed in an oil bath which was maintained at a specific test temperature and the temperature-time curve was measured. From the curve, the following parameters were calculated. Gel time (GT) = time in minutes elapsed between 16.7 ° C below and 5.6 ° C above the bath temperature. Exothermic Peak Time (TTP) = time elapsed between the start of the experiment and the time at which the peak temperature was reached. Exothermic peak (PE) = the maximum temperature that was reached. The results are shown in table 2.

TABLE 2 EXAMPLE 7 Synthesis of highly solid acrylic resins The desirability of the peroxides according to the invention for the production of highly solid acrylic resins was determined and compared with terbutylperoxy-2-ethyl hexanoate. The polymerizations were conducted under nitrogen in a glass covered reactor equipped with a turbine agitator, a thermocouple, a reflux condenser, and an injection opening. The peroxide initiator was added to the monomers. This mixture was metered into the solvent in a stirring vessel by a laboratory pump at the prescribed temperature in about 4 hours. The reaction was continued for an additional hour to reduce the residual monomers of initiators. For the resins obtained, the molecular weights, color and percentage of solids were determined. The temperature was 165 ° C. The results are shown in table 3.

TABLE 3 Recipe: monomers (in parts by weight): 40 n-butyl acrylate (BA): 20 2-hydroxyethyl methacrylate (HEMA): 28 methyl metracylate (MMA): 10 methacrylic acid 2 Solvesso 100 (S-100): 40 (solvent) initiator concentration: 30 meq / 100 g monomers temperature: 165 ° C. The molecular weights were determined by gel permeation chromatography using the polystyrene standards, according to the method AR / 94 14-1 / HPLC obtained from Akzo Nobel. The solids content was determined by the percentage of non-volatile matter (0.5 hours at 150 ° C).

NOVELTY OF THE INVENTION CLAIMS 1. - A process for the preparation of peroxide having the general formula (I), wherein n = 1 or 2, R 1, R 2, R, R 5, and R 6 are independently selected from the group consisting of hydrogen, C 1 -C 2 alkyl, C 3 -C 2 cycloalkyl, C 6 -C 20 aryl, aralkyl C7-C20, and C7-C20 alkaryl, or R1 and R2 form a C3-C2 cycloalkyl group whose groups may include incal or branched alkyl portions; and each of the R1; R2, R, R5, and Re can be substituted with one or more groups selected from hydroxy, alkoxy, linear or branched alkyl, aryloxy, halogen, ester, carboxy, nitrile, and amido, and R3 is independently selected from the group comprising alkyl of C1-C20, C3-C20 cycloalkyl, C6-C2o aryl, C7-C20 aralkyl and C7-C20 alkaryl, which groups may include linear or branched alkyl portions; and R3 may optionally be substituted with one or more groups selected from hydroxy, alkoxy, linear or branched alkyl, aryloxy, halogen, ester, carboxy, nitrile, and amido, and any pair of R3, R, R5 and Re optionally substituted may forming a ring, comprising the reaction of the corresponding ketone peroxide with the general formula (II) wherein n, R-i and R2 have the identified meaning, with an alkylvinyl ether with the general formula (Illa) or an acetal with the general formula (IIIb) wherein R3, t, R5 and Re have the identified meaning, in the presence of an acid catalyst. 2. A process according to claim 1, further characterized in that R4 is hydrogen. 3. A process according to claim 1 or 2, further characterized in that R5 and / or R6 are hydrogen. 4. A process according to claims 1-3, further characterized in that the equivalent amount of alkyl vinyl ether (Illa) or acetal (lllb) is in the range of 1-5 equivalents of ketone peroxide, preferably in the range of 1.5-3.0 equivalents, more preferably in the range of 2.0-2.5 equivalents.

. - A process according to claims 1-4, further characterized in that the ketone peroxide II is a mixture of ketone peroxide having the general formula Ia, and of the ketone peroxide with the general formula llb. 6. - A process according to claims 1-5, further characterized in that the ketone peroxide is derived from methyl ethyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, ketones, cyclohexanone, and / or 3,3,5-trimethylcyclonexanone, preferably from methyl isobutyl ketone or methyl ethyl ketone. . 7. A process according to claims 1-6, further characterized in that the alkyl vinyl ether (Illa) was selected from ethyl vinyl ether, isobutylvinyl ether, propylvinyl ether and butylvinyl ether, preferably isobutylvinyl ether, or the acetal (IIIb). selected from 2,2-dimethoxypropane, 2,2-diethoxypropane, 1,1-dimethoxybutane, 2-propyl-1,3-dioxolane, 1,1-dimethoxyethane, 1,1-diethoxyethane, 1,1-diethoxypropane, and 1 , 1-dimethoxycyclohexane, preferably 1,1-dimethoxyethane. 8. - A peroxide for preparing a peroxide having the formula (I) wherein n, R1, R2, R3, R4, R5 and Re have the meaning identified as given in claims 1-7. 9. The use of a peroxide according to claim 8, further characterized in that it is used as a polymerization initiator, a curing agent for unsaturated polyesters, and / or a modifying agent. 10. A formulation comprising a peroxide according to claim 9, as well as a vehicle or diluent. 11. A formulation according to claim 10, further characterized in that it comprises the peroxide in an amount of 1.0-99%, preferably 10-90% by weight, more preferably 30-90%, more preferably 40-80 % in weigh. 12. A formulation according to claim 10 or 11, further characterized in that the vehicle or diluent is a solid, liquid or paste. 13. A formulation according to claims 10-12, further characterized in that the liquid is a polar solvent. 14. - A formulation according to claims 10-13, further characterized in that it has the form of a dispersion, such as a suspension or emulsion.

Claims (1)

1. SUMMARY OF THE INVENTION The present invention relates to a new class of peroxides and to a process for the preparation of these peroxides having the formula (I) wherein n = 1 or 2, Ri, R2, R, R5 and Rd are independently selected from the group consisting of hydrogen, C?-C20 alkyl C3-C20 cycloalkyl C6-C20 aryl, C7 aralkyl -C20 and C7-C20 alkaryl or R1 and R2 form a C3-C12 cycloalkyl group, which groups may include linear or branched alkyl portions; and each of R1, R2, R, R5 and Re may, optionally, be substituted with one or more groups which are selected from hydroxy, alkoxy, linear or branched alkyl, aryloxy, halogen, ester, carboxy, nitrile and amido and R1 and R2 can form a ring, and R3 is independently selected from the group consisting of C?-C2o alkyl, C3-C2 cycloalkyl, C6-C20 aryl, C7-C20 aralkyl and C7-alkaryl. C201 whose groups may include linear or branched alkyl portions; and R3 in optional form may be substituted with one or more groups selected from hydroxy, alkoxy, linear or branched alkyl, aryloxy, halogen, ester, carboxy, nitrile and amido and any pair of optionally substituted R3, R4, R5 and RT they can form a ring, which comprises the reaction of the corresponding ketone peroxide with the general formula (II), in which n, Ri and R2 have two identified meanings, with an alkylvinyl ether with the general formula (Illa) R, -O- = C- -R «(Illa) R4 Re or with an acetal with the general formula (lllb) wherein R3, R4, R5 and Re have the meanings identified, in the presence of a catalyst; it also relates to the use of these peroxides as polymerization initiators, unsaturated polyester curing and / or modifying agent and to formulations comprising these peroxides and a carrier or diluent.