Composition comprising at least one solid organic peroxide

Abstract

The present invention relates to a composition comprising at least one solid organic peroxide, at least one polyol having a melting temperature of less than 40 DEG C, preferably less than 30 DEG C, more preferably less than 20 DEG C, at least one dispersant and at least one thickener. The invention also relates to the use of a composition as defined previously as a polymerization initiator, polymer modifier or bleaching agent. The invention also relates to a method for preparing such a composition.

Description

Technical Field

[0001] The present invention relates to a composition comprising at least one solid organic peroxide, at least one polyol having a melting temperature (melting temperature) below 40° C., preferably below 30° C., more preferably below 20° C., at least one dispersant and at least one thickener. The present invention also relates to the use of said composition as a polymerization initiator, polymer modifier or bleaching agent. The present invention also relates to a process for preparing such a composition. Background Art

[0002] Organic peroxides generally constitute highly unstable substances, since they decompose relatively easily under the effect of a slight input of heat. Therefore, in the event of an uncontrolled increase in their storage temperature, certain organic peroxides may undergo a self-accelerating exothermic decomposition, leading to fire and / or violent explosions. Furthermore, under these conditions, some of these organic peroxides significantly release flammable vapors capable of reacting with any ignition source, which may significantly increase or even accelerate the risk of violent explosions.

[0003] This dangerous behavior has therefore proven to be incompatible with the current rules on the transport and storage of dangerous goods. It is worth noting that it is important to take appropriate precautions during the storage and handling of such organic peroxides, in particular by ensuring that they are kept below their self-accelerating decomposition temperature T SAD to minimize the risk of fire and / or uncontrolled decomposition.

[0004] In order to overcome these various disadvantages, the organic peroxide can be diluted or mixed with an inert product (that is to say, a product that does not react when in contact with the organic peroxide, called a desensitizer (sensitizer)). There are several possibilities: dissolution in a liquid desensitizer, mixing with a solid inert desensitizer. The organic peroxide composition thus obtained is a suspension or a paste. In particular, the desensitizer makes it possible to limit the effects of uncontrolled decomposition processes of the organic peroxide and thus reduce the various risks associated with its handling.

[0005] However, such compositions must remain stable over time, in particular to avoid phase separation (decantation, clarification) between solid organic peroxide and desensitizing agent. Furthermore, such compositions must be easy to handle and meter for better use, in particular in thermosetting resins. Summary of the invention

[0006] One of the objects of the present invention was therefore in particular to propose a stable and homogeneous composition based on organic peroxides, which is particularly intended for use as a polymerization initiator or as a polymer modifier (for example as a polymer crosslinker, grafting agent or rheology modifier), or as a bleaching agent and which does not have the disadvantages previously described.

[0007] A subject of the present invention is therefore in particular a composition comprising:

[0008] - at least one solid organic peroxide,

[0009] - at least one polyol having a melting temperature of less than 40°C, preferably less than 30°C, more preferably less than 20°C,

[0010] - at least one dispersant, and

[0011] - At least one thickener.

[0012] The composition according to the invention therefore represents an organic peroxide composition having the necessary viscosity for easy handling while remaining stable both in storage and during handling.

[0013] The invention also relates to the use of the composition according to the invention as a polymerization initiator, in particular as a polymerization initiator for acrylic resins or unsaturated polyester resins, preferably acrylic resins, as a polymer modifier, in particular as a polymer crosslinker, grafting agent or rheology modifier, or as a bleaching agent, in particular as a laundry bleaching agent.

[0014] The present invention also relates to a process for preparing a solid organic peroxide composition comprising the steps of mixing at least one solid organic peroxide, at least one polyol having a melting temperature of less than 40°C, preferably less than 30°C, more preferably less than 20°C, at least one dispersant and at least one thickener.

[0015] Other characteristics and advantages of the invention will become more apparent from reading the following description and examples.

[0016] Hereinafter, unless otherwise stated, the limits of a range of values ​​are included in the range.

[0017] The expression "at least one" is equivalent to the expression "one or more".

[0018] composition

[0019] For the purposes of the present invention, "ambient temperature" is understood to mean a temperature in the range of 15°C to 27°C, preferably in the range of 20°C to 25°C.

[0020] For the purposes of the present invention, "solid organic peroxide" is understood to mean that the compound is in the solid state at ambient temperature and at atmospheric pressure (about 0.1 MPa).

[0021] Preferably, the solid organic peroxide is selected from the group consisting of solid diacyl peroxides, solid peroxydicarbonates, solid ketone peroxides, solid peroxyesters (peroxyesters), solid hydroperoxides, solid dialkyl peroxides and mixtures thereof.

[0022] The solid diacyl peroxide is preferably selected from dibenzoyl peroxide, di(2-methylbenzoyl) peroxide, di(methoxybenzoyl) peroxide, di(2-methoxycarbonylbenzoyl) peroxide, di(2-benzylbenzoyl) peroxide, di(2-benzylbenzoyl) peroxide, di(4-fluorobenzoyl) peroxide, di(3-chlorobenzoyl) peroxide, di(4-chlorobenzoyl) peroxide, di(2,4-dichlorobenzoyl) peroxide, dibenzoyldiperoxyadipate, benzoyl octadecanoyl peroxide, dilauroyl peroxide, dihexadecanoyl peroxide, di(chloroacetyl) peroxide and di(3-carboxypropionyl) peroxide.

[0023] The solid peroxydicarbonate is preferably a dialkyl peroxydicarbonate, in particular selected from dibenzyl peroxydicarbonate, dicyclohexyl peroxydicarbonate, di(cis-3,3,5-trimethylcyclohexyl) peroxydicarbonate, di(4-tert-butylcyclohexyl) peroxydicarbonate, dibornyl peroxydicarbonate, di(2-phenoxyethyl) peroxydicarbonate, di-n-tridecyl peroxydicarbonate and di-n-hexadecyl peroxydicarbonate.

[0024] The solid ketone peroxide is preferably selected from di(1-hydroxycyclohexyl)peroxide, 1-hydroxycyclohexyl-1-hydroperoxycyclohexyl, di(hydroperoxycyclohexyl)peroxide and 3,5-dihydroxy-3,5-dimethyl-1,2-dioxolane.

[0025] The solid peroxyester is preferably selected from di-tert-butyl diperoxyterephthalate, di-tert-butyl diperoxysuccinate, di-tert-butyl diperoxyadipate, di-tert-butyl diperoxyphthalate, peroxy-(tert-butyl 3-carboxypropionate), peroxy-(tert-butyl 3-carboxy-2-propenoate) and 2,5-dimethyl-2,5-di(benzoylperoxy)hexane.

[0026] The solid alkyl hydroperoxide is preferably selected from 2,5-dimethyl-2,5-dihydroxyperoxyhexane, 2,5-dimethyl-2,5-dihydroxyperoxy-3-hexyne, 2,7-dimethyl-2,7-dihydroperoxy-3,5-octadiyne, 1,4-bis(1-methyl-1-hydroxyperoxyethyl)benzene and 1,3,5-tris(1-methyl-1-hydroxyperoxyethyl)benzene.

[0027] The solid dialkyl peroxide is preferably selected from dicumyl peroxide, 1,4-di[1-methyl-1-(tert-butylperoxy)ethyl]benzene, 1,3-di[1-methyl-1-(tert-butylperoxy)ethyl]benzene and di(isopropylcumyl)peroxide.

[0028] Preferably, the solid organic peroxide is selected from solid diacyl peroxides, solid peroxydicarbonates and mixtures thereof. Even more preferably, the solid organic peroxide is selected from solid diacyl peroxides.

[0029] Preferably, the organic peroxide is a substituted or unsubstituted dibenzoyl peroxide, more preferably unsubstituted dibenzoyl peroxide, such as is available from Arkema under the trade name Products for sale.

[0030] The solid organic peroxide is preferably present in a content ranging from 10% to 70% by weight, preferably in a content ranging from 20% to 60% by weight, more preferably in a content ranging from 30% to 55% by weight, more preferably in a content from 40% to 50% by weight, relative to the total weight of the composition according to the invention.

[0031] The composition according to the invention comprises a polyol having a melting temperature of less than 40°C, preferably less than 30°C, more preferably less than 20°C.

[0032] The melting temperature is determined by differential scanning calorimetry (DSC) at a heating rate of 10° C. / min. The melting temperature therefore corresponds to the top of the endothermic melting peak obtained during the measurement.

[0033] Preferably, the polyol having a temperature of less than 40°C, preferably less than 30°C, more preferably less than 20°C is selected from glycerol or diglycerol and mixtures thereof.

[0034] Particularly preferably, the polyol is glycerol.

[0035] Preferably, the polyol is present in an amount of 5% to 60% by weight of the composition, preferably 10% to 50% by weight of the composition, more preferably 20% to 45% by weight of the composition.

[0036] The composition according to the invention further comprises at least one dispersant, which may be ionic or nonionic.

[0037] Preferably, the dispersant has an HLB of less than 14, preferably less than 13, more preferably less than 12.

[0038] "HLB" or "HLB value" is understood to mean the hydrophile-lipophile balance which enables the solubility of a dispersant in water to be assessed. Preferably, the HLB is determined according to the method proposed by Griffin (Journal of the Society of Cosmetic Chemists, 5(4), (1954), 249-256).

[0039] If the composition comprises more than one dispersant according to the invention, the HLB of the dispersants can be calculated from the mass ratio of the dispersants.

[0040] Preferably, the nonionic dispersant is selected from linear or nonlinear ethoxylated fatty alcohols, more preferably nonlinear ethoxylated fatty alcohols, more preferably ethoxylated phenols, aliphatic salts such as sodium oleate and potassium soap of castor oil; alkyl allyl sulfonates such as salts of N-acyl amino acids, alkyl ether carboxylates, acylated peptides, alkyl sulfonates and sodium dodecylbenzenesulfonate; salts of sulfuric acid esters of higher alcohols such as alkyl naphthalenesulfonates, derivatives of naphthalenesulfonates, sodium salts of β-naphthalenesulfonic acid formaldehyde (formalin) condensates, dialkyl sulfosuccinates, α-olefin sulfonates, N-acyl sulfonates and sodium cetyl sulfate; and macromolecular surfactants such as polyoxyethylene alkyl ether sulfates, polyoxyethylene alkylphenol ether sulfates. Salts, alkylamide sulfates, alkyl phosphates, alkyl ether phosphates, alkyl allyl ether phosphates and polycarboxylates, polyoxyethylene alkyl ethers such as polyoxyethylene stearyl ether, polyoxyethylene alkyl allyl ethers such as polyoxyethylene nonylphenyl ether, condensed polyoxyethylene alkyl allyl ethers of formaldehyde, block polymers using polyoxypropylene as lipophilic groups, polyoxyethylene ethers of glycerol esters, sorbitan esters such as sorbitan monooleate, polyoxyethylene ethers of sorbitan esters, polyoxyethylene ethers of sorbitan esters, polyethylene glycol fatty acid esters, glycerol esters, polyglycerol esters, propylene glycol esters, sucrose esters, fatty acid alkanolamides, polyoxyethylene fatty acid amides, polyoxyethylene alkylamines and amine oxides.

[0041] Preferably, the nonionic dispersant is a linear or non-linear ethoxylated fatty alcohol, more preferably a non-linear ethoxylated fatty alcohol, more preferably an ethoxylated phenol.

[0042] Preferably, when the fatty alcohol is linear, it comprises at least 16 carbon atoms, and more preferably it comprises at least 16 carbon atoms and is unsaturated.

[0043] Preferably, the dispersant is from Arkema LP.

[0044] Preferably, the dispersant comprises 0.1 wt % to 20 wt % of the composition, preferably 0.5 wt % to 20 wt % of the composition, preferably 0.5 wt % to 10 wt % of the composition, more preferably 1 wt % to 5 wt % of the composition.

[0045] The composition according to the invention further comprises at least one thickener.

[0046] "Thickener" is understood to mean a compound capable of increasing the viscosity of a liquid phase.

[0047] Thickeners may be organic or inorganic.

[0048] Preferably, the organic thickener is a polymer, preferably selected from carboxylic acid homopolymers, copolymers and terpolymers, functionalized celluloses such as cellulose ethers and esters, carboxymethyl cellulose, functionalized carboxymethyl cellulose; polysaccharides, preferably selected from xanthan gum, guar gum, locust bean gum, carrageenan, alginates, locust bean gum, gellan gum, pectin, carrageenan, agar gum, preferably selected from xanthan gum, guar gum, locust bean gum, carrageenan and alginates; polyacrylates, polymethacrylates, functionalized polystyrenes (SMA polymers), alpha-methylstyrene polymaleic acid, functionalized hydroxyethyl cellulose esters, and functionalized and / or halogenated polyolefins.

[0049] Preferably, the inorganic thickener is selected from bentonite, hectorite, silica, kaolinite, montmorillonite, attapulgite and mixtures thereof.

[0050] Preferably, the thickener is a polysaccharide, preferably selected from xanthan gum, guar gum, locust bean gum, carrageenan, alginates and mixtures thereof.

[0051] Particularly advantageously, the thickener is xanthan gum.

[0052] Preferably, the thickener comprises 0.05 wt % to 20 wt % of the composition, preferably 0.1 wt % to 10 wt % of the composition, more preferably 0.3 wt % to 5 wt % of the composition.

[0053] Preferably, at least 50% by weight, preferably at least 60% by weight, more preferably 70% by weight, more preferably 80% by weight and particularly preferably 90% by weight of the solid organic peroxide particles in the composition have a size of less than 500 microns. Preferably, at least 50% by weight of the solid organic peroxide particles in the composition have a size greater than or equal to 100 microns and strictly less than 500 microns (thus excluding the value of 500 microns).

[0054] The size of the particles of the composition can be measured by various measuring techniques, particularly (dynamic and static) light scattering techniques, by the measurement of sedimentation rate and microscope. Preferably, the particle size of the composition according to the present invention is measured by dry sieving, which comprises measuring the weight of the material through the calibration mesh of the screen cloth. The sieves are overlapped by reducing the mesh, and the weight of the material retained on each sieve is measured. This operation can be carried out by vibrating the entire sieve column using a VE 1000 vibrating screen from Retsch, operating for 20 minutes at an oscillation angle of 1.5 mm.

[0055] Preferably, the composition according to the invention comprises water.

[0056] Preferably, the composition according to the invention comprises water to form the remainder of the composition (up to 100%). Preferably, the water is deionized water or distilled water.

[0057] Preferably, the composition according to the invention comprises less than 30% by weight of water, preferably less than 25% by weight of water, more preferably less than 20% by weight of water, relative to the total weight of the composition.

[0058] Preferably, the composition according to the invention has a viscosity ranging from 2000 to 30 000 mPa.s (milliPascal seconds), preferably from 5000 to 15 000 mPa.s, measured at 25° C. with a Brookfield viscometer equipped with a Helipath TE spindle rotating at a speed of 20 rpm.

[0059] The composition may also comprise at least one mineral filler, preferably silica.

[0060] Preferably, the composition according to the invention has a stability of at least 6 months at 20°C, preferably at least 9 months at 20°C, more preferably at least 12 months at 20°C.

[0061] For the purposes of the present invention, "stability" is understood to mean the shelf life, ie the time elapsed between the preparation of the composition and the first signs of phase separation, indicated by emulsification with water or decanting of the solid organic peroxide.

[0062] Separation can be determined visually.

[0063] Method for preparing the composition

[0064] The present invention also relates to a process for preparing a solid organic peroxide composition, comprising the steps of mixing at least one solid organic peroxide, at least one polyol having a melting temperature of less than 40°C, preferably less than 30°C, more preferably less than 20°C, at least one dispersant and at least one thickener.

[0065] Preferably, the process for preparing the composition is carried out at ambient temperature.

[0066] Preferably, the at least one solid organic peroxide is as defined above.

[0067] Preferably, the at least one polyol having a melting temperature of less than 40°C, preferably less than 30°C, more preferably less than 20°C is as defined above.

[0068] Preferably, the at least one non-ionic dispersant is as defined above.

[0069] Preferably, the at least one thickener is as defined above.

[0070] Preferably, the process according to the invention is a process for preparing a passivated organic peroxide. The passivated organic peroxide thus obtained is stable during storage and handling.

[0071] The mixing step can be performed, for example, using a rotor / stator apparatus such as the Ultra Colloid mill, bead mill, ball mill, Dispax reactor, ultrasonic mill or by a dispersing device equipped with a butterfly rotor and / or Cowles blade disperser.

[0072] use

[0073] The invention also relates to the use of a composition as defined above as a polymerization initiator, in particular as a polymerization initiator for acrylic resins or unsaturated polyester resins, preferably acrylic resins, or as a polymer modifier, for example as a polymer crosslinker, grafting agent or rheology modifier, or as a bleaching agent, in particular as a laundry bleaching agent.

[0074] Preferably, the invention relates to the use of a composition as defined above as a polymerization initiator for acrylic resins or unsaturated polyester resins.

[0075] The invention also relates to a process for polymerizing a polymerizable composition comprising the step of contacting said polymerizable composition with a composition according to the invention.

[0076] The polymerization procedure follows prior art polymerization procedures well known to those skilled in the art.

[0077] The invention also relates to the resins obtainable by said process.

[0078] The invention also relates to a process for modifying a polymer, for example for crosslinking a polymer, for grafting or for modifying rheology, comprising the step of contacting said polymer with a composition according to the invention.

[0079] The modification method is in accordance with the prior art modification method known to those skilled in the art.

[0080] The invention also relates to polymers obtainable by the modification process according to the invention.

[0081] The invention also relates to a process for bleaching a product, in particular laundry, comprising the step of contacting said product with a composition according to the invention. DETAILED DESCRIPTION

[0082] The following examples serve to illustrate the invention but are not to be construed as limiting.

[0083] Example

[0084] A. Preparation of Solid Organic Peroxide Compositions

[0085] Glycerin (GLICERINA 99,5 VEG.PH EUR EP 212 from Oqema Spa) and a dispersant ( LP (HLB = 6.3)) was added to a 250ml plastic beaker. The organic peroxide was then added and then mixed at a speed of 1000rpm for 10 minutes using an IKA mixer equipped with a R 1381 3-blade propeller stirrer (stirrer diameter 45mm, shaft diameter 8mm, shaft length 350mm). Finally, a thickener (xanthan gum, XANTHAN GUM FCC / USP PH.EUR from Jungbunzlauer Austria AG) was introduced into the composition and mixed again at 1000rpm for 5 minutes. The test was carried out at ambient temperature (23 ± 2°C). The content used is specified in the following table:

[0086] [Table 1]

[0087]

[0088] B. Particle Size Distribution

[0089] 2 g of the previously obtained sample is placed on a 500 μm nylon cloth, which itself is placed on top of a 250 ml beaker. The sample is washed with 50 ml of ethanol. Visually inspect the filter. Note whether there are no particles remaining on the filter or whether there are one or more particles remaining on the filter.

[0090] C. Appearance of the composition

[0091] The appearance of the composition obtained in step A was visually analyzed.

[0092] D. Results

[0093] The results obtained are presented in the following table:

[0094] [Table 2]

[0095]

[0096] E. Conclusion

[0097] It was observed that the combined use of a thickener and a dispersant enables to obtain a composition which is very stable over a prolonged storage period.

[0098] Furthermore, it should be noted that insufficient amounts of dispersant will not result in a homogeneous mixture.

Claims

1. A composition comprising: - 10% to 70% by weight of at least one solid organic peroxide, relative to the total weight of the composition, - at least one polyol having a melting temperature of less than 40°C, preferably less than 30°C, more preferably less than 20°C, - 0.5% to 20% by weight of at least one dispersant, relative to the total weight of the composition, and - At least one thickener.

2. The composition according to claim 1, wherein the organic peroxide is selected from the group consisting of solid diacyl peroxides, solid peroxydicarbonates, solid ketone peroxides, solid peroxyesters, solid hydroperoxides, solid dialkyl peroxides and mixtures thereof, preferably solid diacyl peroxides.

3. A composition according to any one of the preceding claims, wherein the solid organic peroxide is present in a content ranging from 20% to 60% by weight, preferably in a content ranging from 30% to 55% by weight, more preferably between 40% and 50% by weight, relative to the total weight of the composition.

4. A composition according to any one of the preceding claims, wherein the polyol is selected from glycerol or diglycerol and mixtures thereof, preferably glycerol.

5. A composition according to any one of the preceding claims, wherein the polyol is present in an amount ranging from 5% to 60% by weight of the composition, preferably from 10% to 50% by weight of the composition, more preferably between 20% and 45% by weight of the composition.

6. A composition according to any one of the preceding claims, wherein the dispersant has an HLB of less than 14, preferably less than 13, more preferably less than 12.

7. A composition according to any one of the preceding claims, wherein the dispersant is a non-ionic dispersant, preferably a linear or non-linear ethoxylated fatty alcohol, more preferably a non-linear ethoxylated fatty alcohol, more preferably an ethoxylated phenol.

8. A composition according to any one of the preceding claims, wherein the dispersant comprises from 0.5% to 10% by weight of the composition, more preferably from 1% to 5% by weight of the composition.

9. A composition according to any one of the preceding claims, wherein the thickener is a polysaccharide, preferably selected from xanthan gum, guar gum, locust bean gum, carrageenan and alginates.

10. A composition according to any one of the preceding claims, wherein the thickener comprises from 0.05% to 20% by weight of the composition, preferably from 0.1% to 10% by weight of the composition, more preferably from 0.3% to 5% by weight of the composition.

11. A composition according to any preceding claim, having a stability of at least 6 months at 20°C, preferably at least 9 months at 20°C, more preferably at least 12 months at 20°C.

12. A composition according to any one of the preceding claims, wherein at least 50% by weight, preferably at least 60% by weight, more preferably 70% by weight, more preferably 80% by weight and particularly preferably 90% by weight of the particles have a size of less than 500 microns.

13. Use of a composition as defined in any of the preceding claims as a polymerization initiator, in particular as a polymerization initiator for acrylic resins or unsaturated polyester resins, preferably acrylic resins, as a polymer modifier, in particular as a polymer crosslinker, grafting agent or rheology modifier, or as a bleaching agent, in particular as a laundry bleaching agent.

14. A process for preparing a solid organic peroxide composition comprising the steps of mixing at least one solid organic peroxide, at least one polyol having a melting temperature of less than 40°C, preferably less than 30°C, more preferably less than 20°C, at least one dispersant and at least one thickener.

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