Composition comprising at least one solid organic peroxide

Abstract

Composition comprising at least one solid organic peroxide The present invention relates to a composition comprising at least one solid organic peroxide, at least one polyol having a melting point 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. The invention also relates to the use of the composition as defined above as a polymerization initiator, as a polymer modifier, or as a bleaching agent. The present invention also relates to a process for preparing such a composition. Reference: no figure

Description

Title of the invention: Composition comprising at least one solid organic peroxide

[0001] 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°C, preferably less than 30°C, more preferably less than 20°C, at least one dispersant and at least one thickener.

[0002] The invention also relates to the use of said composition as a polymerization initiator, as a polymer modifier, or as a bleaching agent.

[0003] The present invention also relates to a process for preparing such a composition.

[0004] Organic peroxides are most often highly unstable species because they decompose relatively easily under the action of a low heat input. Thus, in the event of an uncontrolled rise in their storage temperature, certain organic peroxides may undergo self-accelerated exothermic decomposition leading to fires and / or violent explosions. Furthermore, under these conditions, some of these organic peroxides release, in particular, combustible vapors capable of reacting with any source of ignition, which may significantly increase, or even accelerate, the risks of violent explosion.

[0005] Such risky behavior is therefore incompatible with the rules in force regarding the transport and storage of dangerous materials. In particular, it is important to take adequate precautionary measures when storing and handling such organic peroxides, in particular by ensuring that temperatures remain below their self-accelerating decomposition temperature TDAa to minimize the risks of fire and / or uncontrolled decomposition.

[0006] In order to overcome these various drawbacks, organic peroxides can be diluted or mixed with inert products, i.e. non-reactive in contact with the organic peroxide, called phlegmatizing agents. Several possibilities exist: solubilization in a liquid phlegmatizer, mixing with a solid inert phlegmatizer. The organic peroxide compositions thus obtained are suspensions or pastes. In particular, phlegmatizing agents make it possible to limit the effects during the uncontrolled decomposition of organic peroxides and consequently reduce the various risks associated with their handling.

[0007] However, such compositions must remain stable over time, in particular to avoid phase separation (decantation, clarification) between the peroxide solid organic and phlegmatizing. Such compositions must also be easy to handle and dose for better use, particularly in thermosetting resins.

[0008] Thus, one of the objectives of the present invention is in particular to propose a composition based on stable and homogeneous organic peroxide, intended in particular to be used as polymerization initiators or as polymer modifiers (for example as polymer crosslinking agent, grafting agent or rheology modifier), or as a bleaching agent and which does not have the previously described drawbacks.

[0009] The present invention therefore relates in particular to a composition comprising:

[0010] - at least one solid organic peroxide,

[0011] - at least one polyol having a melting temperature of less than 40°C, preferably lower than 30°C, more preferably lower than 20°C,

[0012] - at least one dispersant, and

[0013] - at least one thickener.

[0014] The composition according to the invention thus represents an organic peroxide composition which has the viscosity necessary to be easily handled while remaining stable, whether during storage or during handling.

[0015] The present 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 crosslinking agent, grafting agent or rheology modifier, or as a bleaching agent, in particular as a laundry bleaching agent.

[0016] The present invention also relates to a process for preparing a solid organic peroxide composition comprising a step 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.

[0017] Other characteristics and advantages of the invention will appear more clearly on reading the description and examples which follow.

[0018] In what follows, and unless otherwise indicated, the limits of a domain of values ​​are included in this domain.

[0019] The expression "at least one" is equivalent to the expression "one or more". Composition

[0020] For the purposes of the present invention, the term "ambient temperature" means a temperature ranging from 15°C to 27°C, preferably ranging from 20°C to 25°C.

[0021] By "solid organic peroxide" is meant, for the purposes of the present invention, that the compound is in the solid state at room temperature and under atmospheric pressure (approximately 0.1 MPa).

[0022] Preferably, the solid organic peroxide is selected from the group consisting of solid diacyl peroxides, solid peroxydicarbonates, solid ketone peroxides, solid peroxy esters, solid hydroperoxides, solid dialkyl peroxides and mixtures thereof.

[0023] The solid diacyl peroxides are preferably selected from the group consisting of 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, dibenzoyl diperoxy adipate, octadecanoyl benzoyl peroxide, dilauroyl peroxide, dihexadecanoyl peroxide, di(chloroacetyl) peroxide, and di(3-carboxypropionyl) peroxide.

[0024] The solid peroxydicarbonates are preferably dialkyl peroxydicarbonates, in particular chosen from the group consisting of dibenzyl peroxydicarbonate, dicyclohexyl peroxydicarbonate, di(cis-3,3,5-trimethylcyclohexyl) peroxydicarbonate, di(4-t-butylcyclohexyl) peroxydicarbonate, dibornyl peroxydicarbonate, di(2-phenoxyethyl) peroxydicarbonate, di-n-tridecyl peroxydicarbonate and di-n-hexadecyl peroxydicarbonate.

[0025] The solid ketone peroxides are preferably selected from the group consisting of di(1-hydroxycyclohexyl) peroxide, 1-hydroxycyclohexyl-1-hydroperoxycyclohexyl, di(hydroperoxycyclohexyl) peroxide and 3,5-dihydroxy-3,5-dimethyl-1,2-dioxolane.

[0026] The solid peroxyesters are preferably selected from the group consisting of di-t-butyl diperoxyterephthalate, di-t-butyl diperoxysuccinate, di-t-butyl-diperoxyadipate, di-t-butyl diperoxyphthalate, peroxy-(t-butyl 3-carboxypropionate), t-butylperoxy-(3-carboxy-2-propenoate) and 2,5-dimethyl-2,5-di(benzoylperoxy)hexane.

[0027] The solid alkyl hydroperoxides are preferably selected from the group consisting of 2,5-dimethyl-2,5-dihydroxyperoxyhexane, 2,5-dimethyl-2,5-dihydroxypoxy-3-hexyne, 2,7-dimethyl-2,7-dihydroperoxy-3,5-octadiyne, 1,4-di(1-methyl-1-hydroxyperoxyethyl)benzene and 1,3,5,-tri(1-methyl-1-hydroperoxyethyl)benzene.

[0028] The solid dialkyl peroxides are preferably selected from the group consisting of by dicumyl peroxide, 1,4-di[1-methyl-l-(tert-butylperoxy)ethyl]benzene, 1,3-di-[1-methyl-l-(tert-butylperoxy)ethyl]benzene and di(isopropylcumyl)peroxide.

[0029] Preferably, the solid organic peroxide is selected from the group consisting of solid diacyl peroxides, solid peroxydicarbonates and mixtures thereof. Even more preferably, the solid organic peroxide is selected from the group consisting of solid diacyl peroxides.

[0030] Preferably, the organic peroxide is dibenzoyl peroxide, substituted or unsubstituted, more preferably unsubstituted dibenzoyl peroxide such as that sold under the trade name Luperox® A75 by the company Arkema.

[0031] 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, and more 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 according to the invention.

[0032] The composition according to the invention comprises a polyol having a melting temperature of less than 40°C, preferably less than 30°C, even more preferably less than 20°C.

[0033] The melting temperature is determined by differential scanning calorimetry (DSC) with a temperature rise rate of 10°C / min. The melting temperature then corresponds to the peak of the endothermic melting peak obtained during the measurement.

[0034] Preferably, said polyol having a melting temperature of less than 40°C, preferably less than 30°C, more preferably less than 20°C, is chosen from the group consisting of glycerol or diglycerol, and mixtures thereof.

[0035] Particularly preferably, said polyol is glycerol.

[0036] Preferably, said polyol is present in a content ranging from 5 to 60% by weight of the composition, preferably 10% to 50% by weight of the composition, more preferably between 20% and 45% by weight of the composition.

[0037] The composition according to the invention further comprises at least one dispersant, which may be ionic or non-ionic.

[0038] Preferably, the dispersant has an HLB of less than 14, preferably less than 13, even more preferably less than 12.

[0039] The term "HLB" or "HLB value" means the hydrophilic-lipophilic balance which makes it possible to assess the solubility of a dispersant in water. Preferably, the HLB is determined according to the method proposed by Griffin (Journal of the Society of Cosmetic Chemists, 5(4), (1954), 249-256).

[0040] If the composition comprises more than one dispersant according to the invention, then the HLB of said dispersants can be calculated from the mass ratio of the dispersants.

[0041] Preferably, the non-ionic dispersant is chosen from the group consisting of linear or non-linear ethoxylated fatty alcohols, more preferably non-linear ethoxylated fatty alcohols, more preferably ethoxylated phenols, aliphatic salts such as sodium oleate and potassium soaps of castor oil; alkylallyl sulfonates such as N-acylamino acid salts, alkyl ether carboxylates, acylated peptides, alkyl sulfonates and sodium dodecylbenzenesulfonates; salts of sulfated esters of higher alcohols such as alkylnaphthalene sulfonates, naphthalene sulfonate derivatives, sodium salts of [3-naphthalene sulfonate-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, alkylamide sulfates, alkyl phosphates, alkyl ether phosphates, alkylallyl ether phosphates and polycarboxylates, polyoxyethylene alkyl ethers such as polyoxyethylene stearyl ether, polyoxyethylene alkyl allyl ethers such as polyoxyethylene nonylphenol ether, condensed polyoxyethylene alkyl allyl ethers of formaldehyde, block polymers using polyoxypropylene as a lipophilic group, polyoxyethylene ethers of glycerol esters, sorbitan esters such as sorbitan monooleate, polyoxyethylene ethers of sorbitan esters, polyoxyethylene ethers sorbitol 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.

[0042] Preferably, said non-ionic dispersant is a linear or non-linear ethoxylated fatty alcohol, more preferably is a non-linear ethoxylated fatty alcohol, more preferably is an ethoxylated phenol.

[0043] Preferably, when the fatty alcohol is linear, it comprises at least 16 carbon atoms, and even more preferably it comprises at least 16 carbon atoms and is unsaturated.

[0044] Preferably, the dispersant is Ensoline® PHE LP from Arkema.

[0045] Preferably, said dispersant represents between 0.1 and 20% by weight of the composition, preferably between 0.5 and 10% by weight of the composition, more preferably between 1 and 5% by weight of the composition.

[0046] The composition according to the invention further comprises at least one thickener.

[0047] The term “thickener” means a compound capable of increasing the viscosity of a liquid phase.

[0048] The thickener can be organic or inorganic.

[0049] Preferably, the organic thickener is a polymer, preferably selected from the group consisting of homo-, co- and ter-polymers of carboxylic acids, functionalized cellulose, such as cellulose ethers and esters, carboxymethylcellulose, functionalized carboxymethylcellulose, polysaccharides, preferably selected from the group consisting of xanthan gum, guar gums, locust bean gum, carrageenans, alginates, locust bean gum, gellan gum, pectin, carrageenans, agar gum, preferably selected from the group consisting of xanthan gum, guar gum, locust bean gum, carrageenans and alginates, polyacrylates, polymethacrylates, functionalized polystyrene (SMA polymers), polymaleic acids alpha-methylstyrene, functionalized hydroxyethylcellulose esters and functionalized and / or halogenated polyolefins.

[0050] Preferably, the inorganic thickener is selected from the group consisting of bentonite, hectorite, silica, kaolinite, montmorillonite, attapulgite and mixtures thereof.

[0051] Preferably, the thickener is a polysaccharide, preferably chosen from the group consisting of xanthan gum, guar gum, carob, carrageenans, alginates and mixtures thereof.

[0052] Particularly advantageously, the thickener is xanthan gum.

[0053] Preferably, said thickener represents between 0.05 and 20% by weight of the composition, preferably between 0.1 and 10% by weight of the composition, more preferably between 0.3 and 5% by weight of the composition.

[0054] Preferably, at least 50%, preferably at least 60%, more preferably 70%, more preferably 80% and particularly preferably 90%, by weight of the solid organic peroxide particles in the composition have a size of less than 500 micrometers. Preferably, at least 50% by weight of the solid organic peroxide particles in the composition have a size greater than or equal to 100 micrometers and strictly less than 500 micrometers (the value of 500 micrometers is therefore excluded).

[0055] The particle size of the composition can be measured using various measurement techniques, including light scattering techniques (dynamic and static), sedimentation velocity measurements, and microscopy. Preferably, the particle size of the composition according to the invention is measured by dry sieving, which consists of measuring the weight of material that passes through the calibrated meshes of a sieve cloth. The sieves are superimposed in decreasing mesh size and the weight of material retained on each sieve is measured. This operation can be achieved by vibrating the entire sieve column using a RETSCH VE 1000 sieve shaker, operating for 20 minutes at an oscillation angle of 1.5 mm.

[0056] Preferably, the composition according to the invention comprises water.

[0057] Preferably, the composition according to the present invention comprises water of so as to form the remainder of the composition (up to 100%). Preferably, the water is deionized water or distilled water.

[0058] Preferably, the composition according to the invention has a viscosity of between 2000 and 30000 mPa.s (milliPascal second), preferably of between 5000 and 15000 mPa.s measured at 25°C with a Brookfield viscometer equipped with a Helipath TE type spindle rotating at a speed of 20 RPM.

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

[0060] Preferably, the composition according to the present 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, the term "stability" means the shelf life, i.e. the time which elapses between the preparation of the composition and the first traces of phase separation which is expressed by the creaming of the water or the decantation of the solid organic peroxide.

[0062] The separation can be determined visually. Method of preparing the composition

[0063] The invention also relates to a process for preparing a solid organic peroxide composition comprising a step 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.

[0064] Preferably, the process for preparing the composition is carried out at room temperature.

[0065] Preferably, said at least one solid organic peroxide is as defined above.

[0066] Preferably, said 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.

[0067] Preferably, said at least one non-ionic dispersant is as defined above.

[0068] Preferably, said at least one thickener is as defined above.

[0069] Preferably, the process according to the invention is a process for preparing a phlegmatized organic peroxide. The phlegmatized organic peroxide thus obtained is stable in storage and handling.

[0070] The mixing step can for example be carried out using a rotor / stator device such as an Ultra Turrax®, colloid mills, pearl mills, ball mills, dispax, ultrasonic grinders or by a dispersion device equipped with butterfly rotors and / or cowles-type blade dispersers. Use

[0071] The invention also relates to the use of the 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 crosslinking agent, grafting agent or rheology modifier, or as a bleaching agent, in particular as a bleaching agent for laundry.

[0072] Preferably, the invention relates to the use of the composition as defined above as an initiator for the polymerization of acrylic resins or unsaturated polyester resins.

[0073] The invention also relates to a process for the polymerization of a polymerizable composition, comprising a step of bringing said polymerizable composition into contact with a composition according to the invention.

[0074] The polymerization step is in accordance with the polymerization steps of the prior art, well known to those skilled in the art.

[0075] The present invention also relates to the resin capable of being obtained with said process.

[0076] The invention also relates to a method for modifying polymers, for example crosslinking polymers, grafting or modifying rheology, comprising a step of bringing said polymer and the composition according to the present invention into contact.

[0077] Said modification method is in accordance with the modification methods of the prior art, well known to those skilled in the art.

[0078] The present invention also relates to the polymer capable of being obtained with the modification process according to the present invention.

[0079] The present invention also relates to a process for bleaching a product, in particular linen, comprising a step of bringing said product into contact with a composition according to the invention.

[0080] The following examples serve to illustrate the invention without, however, being limiting in nature. EXAMPLES

[0081] A. Preparation of a solid organic peroxide composition

[0082] In a 250 ml plastic beaker, glycerol (GLICERINA 99.5 VEG. PH EUR EP 212 from Oqema Spa) was added, followed by the dispersant (Ensoline® PHE LP from Arkema (HLB = 6.3)). The organic peroxide was then added and mixed for 10 minutes with an IKA mixer equipped with a propeller rod, 3 blades model R 1381 (Agitator diameter 45 mm, Shaft diameter 8 mm, Shaft length 350 mm) at a speed of 1000 RPM. Finally, the thickener (xanthan gum, XANTHAN GUM FCC / USP PH.EUR from Jungbunzlauer Austria AG) was introduced into the composition, which was mixed again at 1000 RPM for 5 minutes. The test is carried out at room temperature (23±2°C). The contents used are specified in the table below.

[0083] [Tables 1] Composition 1 Composition 2 % by weight Mass (g) % by weight Mass (g) Glycerol 41% 41 41.5% 41.5 Ensoline® PHE LP 2.5% 2.5 2.5% 2.5 Luperox® A75 E (75% benzoyl peroxide in water) 56.0% 56.0 56.0% 56.0 Xanthan gum 0.5% 0.5 0% 0 TOTAL 100.0% 100.0 100.0% 100.0 B. Particle size distribution

[0084] 2 g of sample obtained previously are placed on a 500 pm nylon cloth, itself placed over a 250 ml beaker. The sample is washed with approx. 50 ml of ethanol. The filter is visually inspected. It is noted whether no particles have remained on the filter or whether one or more particles remain on the filter. C. Appearance of the composition

[0085] The appearance of the composition obtained in step A is analyzed visually. D. Results

[0086] The results obtained are presented in the table below:

[0087] [Tables2] Composition Presence of organic peroxide particles with a diameter > 500pm Appearance at the end of mixing Appearance after 1 month of storage at room temperature (23±2°C) Appearance after 12 months of storage at room temperature (23±2°C) 1 non Homogeneous Homogeneous Homogeneous 2 non Homogeneous Heterogeneous (presence of a semi-transparent liquid supernatant on the surface) Heterogeneous (abundant presence of a semi-transparent liquid supernatant on the surface) E. Conclusion

[0088] It is observed that the use of a thickener in combination with a dispersant makes it possible to obtain a very stable composition over a prolonged storage period.

Claims

Claims

1. Composition comprising: - 10 to 70% by weight relative to the total weight of the composition of 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, - 0.5 and 20% by weight relative to the total weight of the composition of at least one dispersant, and - at least one thickener.

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

3. Composition according to any one of the preceding claims, in which 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 preceding claim, wherein said polyol is selected from the group consisting of glycerol or diglycerol, and mixtures thereof, preferably is glycerol.

5. Composition according to any one of the preceding claims, in which said polyol is present in a content ranging from 5 to 60% by weight of the composition, preferably 10% to 50% by weight of the composition, more preferably between 20% and 45% by weight of the composition.

6. Composition according to any one of the preceding claims, in which the dispersant has an HLB of less than 14, preferably less than 13, even more preferably less than 12.

7. Composition according to any one of the preceding claims, in which said dispersant is a non-ionic dispersant, preferably is a linear or non-linear ethoxylated fatty alcohol, more preferably is a non-linear ethoxylated fatty alcohol, more preferably tially is an ethoxylated phenol.

8. Composition according to any one of the preceding claims, in which said dispersant represents between 0.5 and 10% by weight of the composition, more preferably between 1 and 5% by weight of the composition.

9. A composition according to any preceding claim, wherein said thickener is a polysaccharide, preferably selected from the group consisting of xanthan gum, guar gum, carob, carrageenans and alginates.

10. Composition according to any one of the preceding claims, in which said thickener represents between 0.05 and 20% by weight of the composition, preferably between 0.1 and 10% by weight of the composition, more preferably between 0.3 and 5% by weight of the composition.

11. Composition according to any one of the preceding claims, said composition 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. Composition according to any one of the preceding claims, in which at least 50%, preferably at least 60%, more preferably 70%, more preferably 80% and particularly preferably 90%, by weight of the particles have a size of less than 500 micrometers.

13. Use of the composition as defined in any one 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 crosslinking agent, 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 a step of mixing at least one solid organic peroxide, at least one polyol having a melting point 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.