Organic peroxide emulsion with ethanol

Abstract

The present invention relates to an organic peroxide emulsion comprising: at least one organic peroxide; at least one emulsifier comprising at least one non-ionic surfactant comprising at least one fatty chain and / or a protective colloid agent; a combination of two or more anti-gelling agents comprising not more than 9.5 wt% of a first anti-freezing agent, at least one second anti-freezing agent, relative to the total weight of the emulsion of ethanol; and water. The present invention also relates to a process for preparing such an emulsion, the use of such an emulsion for the polymerization or copolymerization of one or more ethylenically unsaturated monomers, and a halogenated vinyl polymer obtained by using such an emulsion.

Description

Technical Field

[0001] This invention relates to an organic peroxide emulsion comprising less than or equal to 9.5% by weight of ethanol and a second antifreeze, a method for its preparation, and its use in the polymerization or copolymerization of one or more olefinic unsaturated monomers. The invention also relates to halogenated vinyl polymers prepared in the presence of such emulsions. Background Technology

[0002] Organic peroxides, in liquid or solid form, are commonly used as polymerization initiators for synthesizing olefinic unsaturated monomers of various types of polymers.

[0003] However, their use often presents a number of problems. Specifically, organic peroxides are generally highly unstable substances because they decompose relatively easily with small amounts of heat input, mechanical energy (friction or impact), or the action of incompatible contaminants. Therefore, if storage temperatures are raised uncontrollably, some organic peroxides can undergo auto-accelerated exothermic decomposition, which can lead to ignition and / or violent explosion. Furthermore, under these conditions, some of these organic peroxides can release flammable vapors that can react with any ignition source, which can greatly increase, or even accelerate, the risk of a violent explosion. Therefore, it is important to take appropriate safety precautions during the storage and transportation of organic peroxides.

[0004] To overcome these drawbacks, organic peroxides are specifically packaged in the form of aqueous (water-containing) emulsions that include antifreeze. The presence of water allows for the absorption and dissipation of energy generated during the exothermic decomposition of the organic peroxide, while the antifreeze maintains the emulsion in a liquid state at temperatures below -10°C, typically below -15°C. This limits the risk of involuntary exothermic decomposition of the organic peroxide.

[0005] Aqueous emulsions typically also contain emulsifiers, which have the advantage of reducing the interfacial tension between the aqueous phase and the organic peroxide to promote the dispersion of the peroxide in droplet form and to maintain the size of the droplets over time. Specifically, over time, the peroxide droplets may precipitate, forming a cream, or undergo Ostwald ripening, or they may aggregate, leading to an increase in their average and maximum size, which in some cases can result in partial or complete phase separation, thus causing overall instability of the emulsion.

[0006] Given the above, organic peroxide aqueous emulsions must therefore be stable not only during their production process but also over a relatively long period during their transportation and storage before being used as polymerization initiators. For this purpose, as mentioned above, organic peroxide droplets must primarily possess small average and maximum sizes that are stable over time.

[0007] Therefore, the peroxide droplets of the organic peroxide emulsion should have a low average size and preferably a uniform size distribution, and should be stable over time, preferably for at least three months. In particular, the maximum diameter of these droplets should very preferably not exceed 20 μm.

[0008] Furthermore, in addition to safety concerns arising from the aforementioned instability, obtaining a homogeneous emulsion with small droplet size is essential for the quality and efficiency of the polymerization process. This is because using non-homogeneous organic peroxide emulsions or emulsions with excessively large droplet sizes as polymerization initiators in vinyl monomer emulsions or suspensions can introduce inhomogeneities into the final product. This inhomogeneity is typically characterized by poorly gelled polymer particles (“fisheyes,” hard particles) during the molten implementation. The presence of these hard particles now renders the polymer material opaque. Therefore, these stability considerations are crucial for applications where the transparency of the final product is critical, particularly for medical applications.

[0009] Furthermore, the use of non-homogeneous organic peroxide emulsions—that is, emulsions with significant differences in the concentration of organic peroxides distributed between the upper and lower parts of the aqueous phase—can also lead to unpredictable variations in initiator concentration within the polymerization reactor. These variations in initiator concentration can cause problems with polymerization time. Too low a concentration reduces reactor productivity due to prolonged polymerization time and can affect polymer quality. Too high a concentration results in a very large energy release during polymerization, thus creating problems with dissipating this energy. The temperature of the polymerization reactor must then be controlled by various cooling methods (such as jackets, cooling counter-pressure plates, or condensers); otherwise, if temperature control is inadequate, polymerization must be stopped.

[0010] Furthermore, the steps of discharging the emulsion into an intermediate storage tank, pumping it, and introducing the organic peroxide emulsion into the polymerization reactor are crucial for the quality of the obtained polymer, the reliability of the polymerization process, and the productivity. These processing steps must be completed within a short timeframe. To achieve this, it is important that the peroxide emulsion has a low viscosity to facilitate its flow.

[0011] Therefore, organic peroxide emulsions should advantageously have a flowability of less than or equal to 200 seconds as measured by the consistency cup technique (e.g., measured according to standard DIN 53211, where the viscosity cup diameter is 4 mm and the temperature is 5 °C).

[0012] Various organic peroxide emulsions have been developed.

[0013] For example, JP 2001064312 describes an emulsion comprising organic peroxides, glycols such as 1,2-propanediol or hexanediol, nonionic surfactants, and polyvinyl alcohol.

[0014] JP S62505 relates to aqueous emulsions comprising organic peroxides, alcohols, preferably diethylene glycol, surfactants, and polyvinyl alcohol.

[0015] EP 1564225 relates to surfactant-free hydroperoxide aqueous emulsions comprising antifreeze selected from the following: methanol, ethanol, ethylene glycol, isopropanol, n-propanol, propylene-1,2-diol, propylene-1,3-diol, glycerol, butan-1-ol, butan-2-ol, butan-1,3-diol, or butan-1,4-diol.

[0016] WO 99 / 31194 describes organic peroxide emulsions that include antifreeze and chlorinated paraffin, as well as optional nonionic surfactants and protective colloids.

[0017] WO 00 / 42078 relates to peroxide emulsions comprising copolymers of α,β-unsaturated dicarboxylic acids and C8-C24 α-olefins, wherein the acid groups are esterified with ethoxylated alcohols and ethoxylated fatty alcohols with an HLB greater than 16.

[0018] US 5,369,197 describes organic peroxide emulsions that include protective colloids (such as polyvinyl alcohol or xanthan gum) and alcohols, particularly methanol, ethanol, or ethylene glycol.

[0019] JP H0676445 relates to peroxide emulsions, which include antifreeze, nonionic surfactants and / or protective colloids, as well as alkali metal ions, alkaline earth metal ions and hydrogen ions.

[0020] GB 2083374 relates to an aqueous emulsion comprising an organic peroxide, an alcohol with a molecular weight of less than 100, and an emulsifier comprising polyvinyl alcohol.

[0021] FR 2995905 relates to an aqueous emulsion of an organic peroxide that does not contain a protective colloid agent, comprising a nonionic surfactant as an emulsifier, and an antifreeze, preferably a mixture of methanol and propane-1,2-diol.

[0022] FR 2995906 describes an organic peroxide aqueous emulsion, wherein the emulsifying agent is a colloidal agent composed of polyvinyl acetate with a degree of hydrolysis greater than 80%.

[0023] DE 102019110214 relates to organic peroxide emulsions, which include nonionic surfactants and mixtures of ethanol and ethylene glycol.

[0024] FR 3099161 relates to ester peroxide emulsions comprising an antifreeze, a mixture preferably of ethanol and propylene glycol, and a combination of at least two emulsifiers selected from non-ethoxylated sorbitol esters, ethoxylated sorbitol esters, and ethoxylated fatty alcohols.

[0025] There is indeed a need for an organic peroxide emulsion that has good stability and good uniformity (preferably over a long period of time) and maintains a small droplet size. Summary of the Invention

[0026] This invention primarily relates to organic peroxide emulsions, comprising:

[0027] - At least one organic peroxide;

[0028] - At least one emulsifier, comprising at least one nonionic surfactant comprising at least one aliphatic chain, and / or a protective colloid agent;

[0029] - A combination of at least two antifreeze agents, comprising a first antifreeze agent consisting of ethanol in an amount less than or equal to 9.5% by weight relative to the total weight of the emulsion, and at least one second antifreeze agent; and

[0030] -water.

[0031] In some embodiments, the at least one second antifreeze agent is an alcohol, preferably selected from monools, diols, triols, and mixtures thereof.

[0032] In some embodiments, the at least one second antifreeze is selected from methanol, ethylene glycol, 2-propanol, 1-propanol, propane-1,2-diol, propane-1,3-diol, glycerol, butane-1-ol, butane-2-ol, butane-1,3-diol, butane-1,4-diol, diethylene glycol, and mixtures thereof.

[0033] In some embodiments, the at least one second antifreeze agent comprises propane-1,2-diol, preferably composed of propane-1,2-diol.

[0034] In some embodiments, the second antifreeze is present in an amount of 3% to 17% by weight, preferably 3% to 9% by weight, more preferably 3% to 8% by weight, relative to the total weight of the emulsion.

[0035] In some embodiments, a combination of at least two antifreeze agents is present in an amount of 10% to 40% by weight, preferably 15% to 25% by weight, relative to the total weight of the emulsion.

[0036] In some embodiments, the at least one organic peroxide is selected from peroxydicarbonate, peroxyester, diacyl peroxide, and combinations thereof.

[0037] In some embodiments, the at least one organic peroxide is selected from tert-amyl peroxypentanoate, tert-butyl peroxypentanoate, tert-butyl peroxydecanoate, tert-amyl peroxydecanoate, 3-hydroxy-1,1-dimethylbutyl peroxydecanoate, cumyl peroxydecanoate, bis(2-ethylhexyl) peroxydicarbonate, bis(3,5,5-trimethylhexyl) peroxide, and mixtures thereof.

[0038] In some embodiments, the at least one organic peroxide is present in an amount of 40% to 80% by weight, preferably 45% to 60% by weight, relative to the total weight of the emulsion.

[0039] In some embodiments, at least one nonionic surfactant comprising at least one fatty chain is selected from oxoalkylated fatty alcohols, oxoalkylated fatty acids, oxoalkylated vegetable or animal oils, polysorbates, dehydrated sorbitol esters, alkyl glucosides, oxoalkylated alkyl glucosides, and mixtures thereof.

[0040] In some embodiments, at least one emulsifier includes at least one protective colloid, preferably at least one polyvinyl alcohol and / or hydrolyzed polyvinyl acetate.

[0041] In some embodiments, the emulsion does not contain polyvinyl alcohol and hydrolyzed polyvinyl acetate.

[0042] In some embodiments, at least one emulsifier comprises at least one nonionic surfactant including at least one aliphatic chain and optionally at least one protective colloid, preferably at least one polyvinyl alcohol and / or hydrolyzed polyvinyl acetate.

[0043] The present invention also relates to a method for preparing the above-mentioned emulsion, comprising the following steps:

[0044] - A mixture of at least one organic peroxide, at least one emulsifier, at least two antifreeze agents, and water; and

[0045] - Emulsify the mixture.

[0046] The present invention also relates to the use of the emulsions described above for the polymerization or copolymerization of one or more olefinic unsaturated monomers, particularly vinyl monomers, preferably halogenated vinyl monomers, and more preferably vinyl chloride.

[0047] The present invention also relates to a haloethylene polymer, which is obtained by polymerizing at least one olefinic unsaturated monomer in the presence of the above-described emulsion.

[0048] The present invention satisfies the above-mentioned requirements. More specifically, it provides a stable and homogeneous organic peroxide emulsion comprising droplets with small average and small maximum droplet sizes, and satisfying the viscosity and flow time requirements of the emulsion. The emulsion according to the invention advantageously remains stable and homogeneous over time, and maintains small average and small maximum droplet sizes, thereby enabling particularly safe long-term transport and storage. Furthermore, when used for the polymerization of olefinic unsaturated monomers, the emulsion according to the invention allows for the production of polymers with low hard particle content.

[0049] This is achieved by using a combination of two antifreeze agents and a specific emulsifier, one of which is ethanol, which is present in the emulsion in an amount of less than or equal to 9.5% by weight. Detailed Implementation

[0050] The invention will now be described in a non-limiting manner and in more detail in the following description.

[0051] In this document, unless otherwise expressly stated, all percentages (%) shown are weight percentages.

[0052] In this document, the quantities expressed for a given substance are applicable to substances according to all given definitions of substances (as mentioned herein), including more restrictive definitions.

[0053] lotion

[0054] This invention primarily relates to organic peroxide emulsions. The emulsion according to the invention is an aqueous emulsion, i.e., it comprises water. Preferably, the water is softened water or deionized water.

[0055] Particularly preferred is an oil-in-water emulsion.

[0056] The emulsion according to the present invention comprises at least one organic peroxide.

[0057] The organic peroxide is preferably selected from peroxydicarbonate, peroxyester and / or diacyl peroxide.

[0058] In dicarbonates, preferred peroxides are diethyl dicarbonate peroxide, diisopropyl dicarbonate peroxide, di-n-propyl dicarbonate peroxide, di-n-butyl dicarbonate peroxide, diisobutyl dicarbonate peroxide, di-tert-butyl dicarbonate peroxide, bis(3-methoxybutyl) dicarbonate peroxide, di-neopentyl dicarbonate peroxide, bis[2-(2-methoxyethoxy)ethyl] dicarbonate peroxide, bis(3-methoxy-3-methylbutyl) dicarbonate peroxide, bis(2-ethoxyethyl) dicarbonate peroxide, bis(2-ethylhexyl) dicarbonate peroxide, and mixtures thereof.

[0059] Among the peroxide esters, preferred peroxides are tert-amyl peroxypentanoate, tert-butyl peroxypentanoate, tert-butyl peroxydecanoate, tert-amyl peroxydecanoate, tert-butyl peroxyisobutyrate, cumyl peroxydecanoate, cumyl peroxyheptanoate, 2,4,4-trimethylpentyl peroxydecanoate, tert-butyl peroxyheptanoate, cumyl peroxyheptanoate, tert-amyl peroxyheptanoate, tert-butyl peroxyheptanoate, tert-amyl peroxy-2-ethylhexanoate, tert-butyl peroxy-2-ethylhexanoate, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, hydroxyperoxide esters, and mixtures thereof.

[0060] As hydroxy peroxide esters that can be used in emulsions according to the present invention, examples include 4-hydroxy-2-methylpentyl peroxynedecanoate, 4-hydroxy-2-methylpentyl peroxy-(2-ethylhexanoate), 4-hydroxy-2-methylpentyl peroxy-2-phenylbutyrate, 4-hydroxy-2-methylpentyl peroxy-2-phenoxypropionic acid, 4-hydroxy-2-methylpentyl peroxy-(2-butyloctanoate), and 4-hydroxy-2-methyl peroxynetridecanoate. Amyl ester, 4-hydroxy-2-methylhexyl peroxynedecanoate, 5-hydroxy-1,3,3-trimethylcyclohexyl peroxynedecanoate, 4-hydroxy-2,6-dimethyl-2,6-bis(neohexanoylperoxy)heptane, 4-hydroxy-2,6-dimethyl-2,6-bis(neohexanoylperoxy)heptane, 3-hydroxy-1,1-dimethylbutyl peroxy-2-ethylhexanoate, 3-hydroxy-1,1-dimethylbutyl peroxynedecanoate, and mixtures thereof.

[0061] Among the diacyl peroxides, preferred peroxides are selected from diisobutyryl peroxide, diheptyl peroxide, bis(2-ethylbutyryl) peroxide, bis(3,5,5-trimethylhexanoyl) peroxide, bis(2-ethylhexanoyl) peroxide, and asymmetric peroxides such as isobutyryl octyl peroxide, isobutyryl decyl peroxide, isobutyryl lauroyl peroxide, 2-ethylbutyryl decyl peroxide, 2-ethylhexanoyl lauroyl peroxide, and mixtures thereof.

[0062] Particularly preferred, the organic peroxide is selected from: tert-butyl peroxyneodecanate, for example, from Arkema. 10 is sold under the name; 3-hydroxy-1,1-dimethylbutyl peroxynedecanoate, for example, by Arkema under the trade name 610 for sale; cumyl peroxide neodecanoate, for example by Arkema under the name 188 for sale; bis(2-ethylhexyl) peroxide dicarbonate, for example by Arkema under the trade name 223 for sale; tert-amyl peroxyneodecanate, for example, by Arkema under the name 546 for sale; tert-butyl peroxypentanoate, for example, by Arkema under the name 11 for sale; tert-amyl peroxypentanoate, for example, by Arkema under the name 554 for sale; bis(3,5,5-trimethylhexanoyl) peroxide, for example by Arkerma under the name 219 for sale; and their mixtures.

[0063] The emulsions according to the invention may comprise a mixture of two or more organic peroxides (particularly those described above).

[0064] Alternatively, the emulsion according to the invention may comprise only one organic peroxide, particularly only one organic peroxide as described above.

[0065] Preferably, the emulsion according to the invention comprises at least one organic peroxide in an amount of 40% to 80% by weight, preferably 45% to 60% by weight, and particularly 55% to 60% by weight, relative to the total weight of the emulsion. Specifically, the amount of peroxide relative to the total weight of the emulsion may be 40% to 45% by weight, 45% to 50% by weight, 50% to 55% by weight, 55% to 60% by weight, or 60% to 65% by weight, or 65% to 70% by weight, or 70% to 75% by weight, or 75% to 80% by weight.

[0066] The organic peroxides according to the invention advantageously have a one-hour half-life temperature of less than or equal to 90°C, preferably less than 80°C, as measured by trichloroethylene.

[0067] Furthermore, the organic peroxides in the emulsion according to the invention advantageously have a storage temperature below 0°C.

[0068] Organic peroxides are advantageously liquid at storage temperatures, preferably below 0°C, and measured at atmospheric pressure.

[0069] The emulsion according to the invention comprises a combination of at least two antifreeze agents. The presence of the antifreeze agents prevents the emulsion from gelling during transport and / or storage at low temperatures (i.e., typically in environments with temperatures below 0°C).

[0070] The emulsion includes a primary antifreeze composed of ethanol.

[0071] Ethanol is present in the emulsion in an amount of less than or equal to 9.5% by weight, relative to the total weight of the emulsion. The emulsion according to the invention may include ethanol in amounts of less than or equal to 9.2% by weight, or less than or equal to 9.0% by weight, or less than or equal to 8.7% by weight, or less than or equal to 8.5% by weight, or less than or equal to 8.2% by weight, or less than or equal to 8.0% by weight. Ethanol may be included in the emulsion in amounts from 0.5% by weight to 9.5% by weight, preferably from 6% by weight to 95% by weight.

[0072] The emulsion also includes at least one second antifreeze agent. The presence of the second antifreeze agent enables the antifreeze composition to be liquid at -20°C.

[0073] The second antifreeze agent is preferably an alcohol. Therefore, the second antifreeze agent can be any alcohol that is water-soluble at the storage temperature (e.g., at 0°C). The term "water-soluble alcohol" refers to an alcohol with a solubility in water exceeding 1% by weight at 0°C. The amount of antifreeze agent in water can be determined by gas chromatography.

[0074] More specifically, the second antifreeze agent may advantageously be a monool, diol, and / or triol.

[0075] Preferably, the second antifreeze is selected from methanol, ethylene glycol, 2-propanol, 1-propanol, propane-1,2-diol, propane-1,3-diol, glycerol, butane-1-ol, butane-2-ol, butane-1,3-diol, butane-1,4-diol, diethylene glycol, triethylene glycol, and mixtures thereof, wherein the mixtures include at least two of the above-mentioned antifreezes. More preferably, the second antifreeze is selected from methanol, ethylene glycol, 2-propanol, 1-propanol, propane-1,2-diol, propane-1,3-diol, glycerol, butane-1-ol, butane-2-ol, butane-1,3-diol, butane-1,4-diol, diethylene glycol, and mixtures thereof, and more particularly from methanol, ethylene glycol, 2-propanol, 1-propanol, propane-1,2-diol, propane-1,3-diol, glycerol, butane-1-ol, butane-2-ol, butane-1,3-diol, butane-1,4-diol, and mixtures thereof. The mixture of antifreezes may include two or more, preferably two, antifreezes as described above.

[0076] Particularly advantageously, the second antifreeze is propane-1,2-diol, optionally as a mixture with one or more antifreezes (preferably as described above). More advantageously, the second antifreeze consists of propane-1,2-diol.

[0077] More preferably, the molar mass of the second antifreeze is less than or equal to 120 g / mol, more preferably less than or equal to 100 g / mol, and even more preferably less than or equal to 80 g / mol. The advantage of using a second antifreeze with a molar mass within this range is that it reduces the amount of second antifreeze added to the emulsion.

[0078] The second antifreeze is preferably included in the emulsion in an amount ranging from 3% to 17% by weight, more preferably from 3% to 9% by weight, and even more preferably from 3% to 8% by weight, relative to the total weight of the emulsion. The emulsion may include 3% to 4% by weight, or 4% to 5% by weight, or 5% to 6% by weight, or 6% to 7% by weight, or 7% to 8% by weight, or 8% to 9% by weight, or 9% to 11% by weight, or 11% to 13% by weight, or 13% to 15% by weight, or 15% to 17% by weight of the second antifreeze relative to the total weight of the emulsion.

[0079] The combination of antifreeze (i.e., the total amount of antifreeze in the emulsion) is preferably present in the emulsion according to the invention at a content of less than or equal to 40% by weight (relative to the total weight of the emulsion), preferably less than or equal to 25% by weight, and more preferably less than or equal to 22% by weight, relative to the total weight of the emulsion. Such an antifreeze content allows the aqueous phase to remain in liquid form at temperatures as low as -20°C, preferably as low as -25°C.

[0080] More specifically, the combination of antifreeze agents in the emulsion may be present in an amount of 10% to 40% by weight, preferably 15% to 25% by weight, relative to the total weight of the emulsion. In some embodiments, the emulsion includes the combination of antifreeze agents in amounts of 10% to 15% by weight, or 15% to 20% by weight, or 20% to 25% by weight, or 25% to 30% by weight, or 30% to 35% by weight, or 35% to 40% by weight, relative to the total weight of the emulsion.

[0081] The emulsion according to the present invention comprises at least one emulsifier.

[0082] Preferably, the emulsifier according to the invention is readily biodegradable. The biodegradability of the emulsifier can be determined by the OECD 301 method, and more particularly by the release of carbon dioxide by the OECD 301B method.

[0083] The emulsifiers according to the present invention comprise or are (i.e., consist of) a nonionic surfactant comprising at least one fatty chain and / or at least one protective colloid agent.

[0084] Therefore, the emulsion according to the invention may include at least one nonionic surfactant comprising at least one aliphatic chain. The term "aliphatic chain" refers to an aliphatic carbon-based chain that optionally includes hydroxyl branches and comprises at least 6 carbon atoms, preferably 6 to 60 carbon atoms, more preferably 6 to 20 carbon atoms. The nonionic surfactant may or may not be oxoalkylated.

[0085] The emulsifier used in the emulsion according to the invention may be (i.e., it may consist of) at least one nonionic surfactant comprising at least one fatty acid chain.

[0086] Preferably, the nonionic surfactant comprises or is selected from the following oxoalkylene-modified or nonoxyalkylene-modified nonionic surfactants: fatty alcohols, fatty acids, sorbitol esters, vegetable or animal oils (hydrogenated or non-hydrogenated), alkyl glucosides, and mixtures thereof. The nonionic surfactant mixture used in this invention may be a mixture of oxoalkylene-modified nonionic surfactants only, or a mixture of nonoxyalkylene-modified nonionic surfactants only, or a mixture of oxoalkylene-modified nonionic surfactants and nonoxyalkylene-modified nonionic surfactants.

[0087] Advantageously, the nonionic surfactant includes or is a nonionic surfactant selected from: oxoalkylated fatty alcohols, oxoalkylated fatty acids, oxoalkylated vegetable or animal oils, polysorbates, dehydrated sorbitol esters, nonoxoalkylated alkyl glucosides, oxoalkylated alkyl glucosides, and mixtures thereof.

[0088] The oxoalkylene unit is more particularly an oxoethylene unit (i.e., an oxoethylene group), an oxopropylene unit (i.e., an oxopropylene group), or a combination of an oxoethylene unit and an oxopropylene unit; preferably, the oxoalkylene unit is an oxoethylene unit or a combination of an oxoethylene unit and an oxopropylene unit.

[0089] Therefore, the nonionic surfactant is preferably selected from: fatty alcohols containing oxyethylidene units and optionally oxypropylene units, fatty acids containing oxyethylidene units and optionally oxypropylene units, vegetable or animal oils containing oxyethylidene units and optionally oxypropylene units (which are optionally hydrogenated), polysorbates, dehydrated sorbitol esters, alkyl glucosides containing oxyethylidene units and optionally oxypropylene units, and mixtures thereof.

[0090] The oxyethylidene unit (i.e., oxyethylidene group) and the oxypropylidene unit (i.e., oxypropylidene group) can be randomly distributed or in block form.

[0091] The molar number of ethylene oxide and / or propylene oxide is preferably 1 to 250, more preferably 2 to 100, even more preferably 2 to 50, and more particularly 2 to 40.

[0092] Preferably, the molar number of ethylene oxide in the emulsifier ranges from 2 to 40.

[0093] For the purposes of this invention, the term "fatty alcohol" refers to an alcohol containing at least 6, preferably at least 8, carbon atoms, more preferably C8-C. 40 Alcohols, preferably C8-C 20 alcohol.

[0094] Among the fatty alcohols that can be used in this invention, particularly 2-octyldodecane alcohol, decanol, lauryl alcohol, oleocetyl alcohol, isodecanol, octanol, oxoisotridecane alcohol, cetearyl alcohol, eleostearyl alcohol, octanoyl alcohol, myristyl alcohol, hexadecyl or palmitol, stearyl alcohol, eicosanol or arachidyl alcohol, behenyl alcohol, oleyl alcohol, eicosanol or eicosanol, docosanol, castor oil alcohol, linoleyl alcohol, linolenyl alcohol, or combinations thereof.

[0095] Preferably, the nonionic surfactant is selected from oxyalkylated fatty alcohols, and more preferably from octyldodecanol, decanol, lauryl alcohol, oleocetyl alcohol, isodecanol, octanol, oxoisotridecanol, cetearyl alcohol, eleostearyl alcohol, octanoyl alcohol, myristol, hexadecyl alcohol or palmitol, stearyl alcohol, eicosanol or arachidonic alcohol, behenol, oleyl alcohol, eicosanol or eicosanol, dodecenol, castor oil alcohol, linoleyl alcohol or linolenyl alcohol, which is oxyalkylated, preferably oxyethylated and / or oxypropylated, and more preferably oxyethylated and optionally oxypropylated.

[0096] More preferred fatty alcohols in the context of this invention are oleocetyl alcohol, cetyl alcohol or palmitol, stearyl alcohol, oleyl alcohol, linoleyl alcohol or mixtures thereof, and even more preferred are their oxyalkylene-modified, preferably their oxyethylene-modified and / or oxypropylene-modified, and even more preferred are their oxyethylene-modified and optionally oxypropylene-modified forms.

[0097] More preferably, the nonionic surfactant is an oxyalkylene fatty alcohol selected from oxyethylene linoleyl alcohol, oxyethylene oleocetyl alcohol, oxyethylene hexadecyl alcohol or palmitol, oxyethylene stearyl alcohol, oxyethylene oleyl alcohol and mixtures thereof.

[0098] The aforementioned fatty alcohols may optionally be oxypropylidene-substituted to a very small extent.

[0099] Preferably, the derivatives of oxyethylated vegetable / animal oils (hydrogenated or non-hydrogenated), especially ethoxylated mono, di, and triglycerides, and including complex mixtures of ethoxylated glycerol, optionally linked to one or more fatty acid chains (which may or may not be ethoxylated), fatty acids ethoxylated on acid functional groups and / or ethoxylated on hydroxyl functional groups carrying fatty acid chains, and variable proportions of fatty acids, glycerol, and fatty acid mono, di, or triglycerides.

[0100] For the purposes of this invention, the term "fatty acid" refers to an acid or mixture of acids comprising at least 6 carbon atoms, preferably 6 to 40 carbon atoms, more preferably 8 to 20 carbon atoms.

[0101] The vegetable / animal oils (hydrogenated or non-hydrogenated) that can be used for oxyalkylation in this invention are preferably selected from optionally hydrogenated, oxyethylated (or ethoxylated) vegetable oils.

[0102] The optional hydrogenated, oxyethylated vegetable oil is preferably selected from ethoxylated castor oil and ethoxyhydrogenated castor oil, wherein each mole of ricinoleic acid comprises 5 to 40 moles of oxyethylidene. Also mentioned are ethoxylated oils derived from: coconut kernel oil, palm oil, olive oil, peanut oil, rapeseed oil, soybean oil, sunflower oil, walnut oil, hazelnut oil, coconut oil, poppy oil, safflower oil, linseed oil, perilla oil, oitica oil, and / or Chinese sesame oil.

[0103] As vegetable / animal oils that can be used as emulsifiers according to the present invention, references may also be made to ethoxylated fats based on: tallow, crude or refined tall oil, whale oil, herring oil, and / or sardine oil. All these ethoxylated glycerol ester derivatives are characterized in that they comprise mixtures of ethoxylated mono, di, or triglycerides and corresponding ethoxylated derivatives of fatty acids and glycerol. These fatty acids are particularly derived from the following saturated or unsaturated fatty acids: hexanoic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, myristoleic acid, palmitoleic acid, oleic acid, ricinoleic acid, linolenic acid, linolenic acid, tung oil acid, octadecanoic acid-9,11,13-trien-4-keto acid (licanic acid), codoleic acid, and / or erneic acid. Some unsaturated fatty acids may or may not be hydrogenated, as in the case of ethoxylated castor oil, where the ricinoleic acid group may or may not be partially or fully hydrogenated.

[0104] In some embodiments, the nonionic surfactant according to the invention may include or be one or more fatty acids, preferably oxoalkylated, more preferably oxoethylated, and optionally oxopropylated, which may be selected from the aforementioned fatty acids.

[0105] Advantageously, the nonionic surfactant may include or be a nonionic surface surfactant selected from oxoalkylated vegetable oils or animal oils (hydrogenated or non-hydrogenated).

[0106] More preferably, the nonionic surfactant may include or be a nonionic surface surfactant selected from vegetable oils, wherein the vegetable oils are optionally hydrogenated, oxyethylated, or optionally oxypropylated.

[0107] More preferably, the nonionic surfactant may include or be selected from ethoxylated, optionally hydrogenated vegetable oils (including 5 to 40 moles of ethylene oxide), particularly ethoxylated castor oil and ethoxylated hydrogenated castor oil (including 20 to 40 moles of ethylene oxide).

[0108] Even more preferably, the nonionic surfactant may include or be ethoxylated castor oil, which includes 20-40 moles of ethylene oxide.

[0109] Advantageously, the nonionic surfactant may include or be one or more nonethoxylated sorbitol esters and / or one or more ethoxylated sorbitol esters. In this document, ethoxylated sorbitol esters are also referred to as “polysorbates,” and the term “sorbitol ester” refers to nonethoxylated sorbitol esters unless otherwise explicitly stated.

[0110] Preferably, the non-ethoxylated sorbitol ester is selected from sorbitol monostearate, sorbitol tristearate, sorbitol monolaurate, sorbitol trilaurate, sorbitol monooleate, sorbitol trioleate, sorbitol monopalmitate, and sorbitol tripalmitate, and combinations thereof.

[0111] Sorbitol monooleate can be branded as Span. (Originated from Croda)

[0112] Preferably, the ethoxylated sorbitol ester (or polysorbate) comprises 3 to 40 ethylene oxide groups, more preferably 5 to 20 ethylene oxide groups.

[0113] Preferably, the ethoxylated sorbitol ester is selected from ethoxylated sorbitol monostearate, ethoxylated sorbitol tristearate, ethoxylated sorbitol monolaurate, ethoxylated sorbitol trilaurate, ethoxylated sorbitol monooleate, ethoxylated sorbitol trioleate, ethoxylated sorbitol monopalmitate, ethoxylated sorbitol tripalmitate, and combinations thereof.

[0114] Sorbitol monooleate 20OE (containing 20 ethylene oxide groups) can be marketed under the brand name Surfaline. (from Arkema) or Tween (Originated from Croda)

[0115] Nonionic surfactants may include or be one or more alkyl glucosides. Examples of alkyl glucosides that may be used in this invention include octyl glucoside, octanoyl glucoside, lauryl glucoside, cocoyl glucoside, hexyl glucoside, isooctyl glucoside, decyl glucoside, and / or undecyl glucoside. These alkyl glucosides may or may not be oxyalkylene-modified (and more particularly ethoxylated or unethoxylated).

[0116] The emulsion may include a combination of at least two nonionic surfactants, each of which may be used independently as described above.

[0117] Preferably, the combination of at least two nonionic surfactants includes unethoxylated sorbitol as defined above and ethoxylated sorbitol comprising 5 to 20 oxyethylidene groups as described above.

[0118] As a supplement to or alternative to the use of one or more nonionic surfactants (such as those described above), the emulsions according to the invention may include at least one protective colloid as an emulsifier. Protective colloids are emulsifiers well known to those skilled in the art. For the purposes of this invention, they refer to polyvinyl alcohol, polyvinyl acetate, and especially partially hydrolyzed polyvinyl acetate, cellulose esters, and xanthan gum.

[0119] Therefore, preferably, the protective colloid in the emulsion according to the invention is selected from polyvinyl alcohol, partially hydrolyzed polyvinyl acetate, cellulose ester, xanthan gum, and mixtures thereof. The hydrolyzed polyvinyl acetate is preferably hydrolyzed to a degree of 5 mol% to 85 mol%, more preferably 5 mol% to 75 mol%.

[0120] At least one emulsifier in the emulsion according to the present invention may consist of at least one protective colloid agent.

[0121] More specifically, the emulsion according to the invention may comprise at least one polyvinyl alcohol and / or at least one hydrolyzed polyvinyl acetate as at least one emulsifier, optionally in combination with one or more surfactants, particularly one or more nonionic surfactants as described above, especially in combination with one or more nonionic surfactants containing at least one fatty chain. At least one emulsifier of the emulsion according to the invention may consist of at least one polyvinyl alcohol and / or at least one hydrolyzed polyvinyl acetate, optionally in combination with one or more surfactants, particularly one or more nonionic surfactants as described above, especially in combination with one or more nonionic surfactants containing at least one fatty chain.

[0122] The emulsifier according to the invention may consist of at least one nonionic surfactant comprising at least one fatty chain and optionally at least one protective colloid agent.

[0123] The emulsifier according to the invention may consist of at least one protective colloid and optionally at least one nonionic surfactant comprising at least one aliphatic chain.

[0124] Alternatively, the emulsion according to the invention may be free of polyvinyl alcohol. The emulsion according to the invention may be free of partially hydrolyzed polyvinyl acetate, and more particularly free of polyvinyl acetate.

[0125] More specifically, the emulsions according to the invention may be free of protective colloids. The absence of protective colloids in the emulsion particularly allows for a reduction in the industrial preparation time of the emulsion, as solid protective colloids (especially polyvinyl acetate) require a pre-dissolution step, and minimizes the risks associated with powder handling. Furthermore, the presence of colloidal protectants in the emulsion can increase its viscosity, which may be undesirable for some applications.

[0126] The emulsion according to the present invention may be free of cellulose esters. The emulsion may be free of xanthan gum.

[0127] The emulsifier may be present in the emulsion according to the invention in an amount ranging from 0.1 wt% to 10 wt%, preferably from 0.5 wt% to 5 wt%, relative to the total weight of the emulsion. In particular, the emulsion may include the emulsifier in the following amounts: 0.1 wt% to 0.5 wt%, or 0.5 wt% to 1 wt%, or 1 wt% to 2 wt%, 2 wt% to 3 wt%, or 3 wt% to 4 wt%, or 4 wt% to 5 wt%, or 5 wt% to 6 wt%, or 6 wt% to 7 wt%, or 7 wt% to 8 wt%, or 8 wt% to 9 wt%, or 9 wt% to 10 wt%, relative to the total weight of the emulsion.

[0128] The emulsion according to the invention may include at least one nonionic surfactant comprising at least one fatty chain in the following amounts: 0.1 wt% to 10 wt%, preferably 0.5 wt% to 5 wt%, relative to the total weight of the emulsion. Specifically, the emulsion may include a nonionic surfactant comprising at least one fatty chain in the following amounts: 0.1 wt% to 0.5 wt%, or 0.5 wt% to 1 wt%, or 1 wt% to 2 wt%, or 2 wt% to 3 wt%, or 3 wt% to 4 wt%, or 4 wt% to 5 wt%, or 5 wt% to 6 wt%, or 6 wt% to 7 wt%, or 7 wt% to 8 wt%, or 8 wt% to 9 wt%, or 9 wt% to 10 wt%, relative to the total weight of the emulsion.

[0129] The emulsion according to the invention may include at least one protective colloid agent in an amount of 0.1% to 10% by weight, preferably 0.5% to 5% by weight, relative to the total weight of the emulsion. Specifically, the emulsion may include a protective colloid agent in an amount of 0.1% to 0.5% by weight, or 0.5% to 1% by weight, or 1% to 2% by weight, or 2% to 3% by weight, or 3% to 4% by weight, or 4% to 5% by weight, or 5% to 6% by weight, or 6% to 7% by weight, or 7% to 8% by weight, or 8% to 9% by weight, or 9% to 10% by weight, relative to the total weight of the emulsion.

[0130] The emulsion according to the invention may also include one or more additives intended to impart specific properties / characteristics to the final composition. These additives will be ideally used for the final polymerization or copolymerization.

[0131] Additives can be selected from defoamers, chain transfer agents, chain extenders, pH adjusters, plasticizers, and mixtures thereof.

[0132] The amount of additive is preferably 0.1% to 10% by weight, more preferably 1% to 5% by weight, relative to the total weight of the emulsion.

[0133] Preferably, the emulsion according to the invention comprises one or more plasticizers, preferably selected from aliphatic esters, such as phthalates, adipates, benzoates, hydrogenated derivatives of these molecules, and mixtures thereof. In particular, the plasticizer may be diisononylcyclohexane, diisononylcyclohexane dicarboxylate, and mixtures thereof. The plasticizer may be present in the emulsion in an amount of 1% to 5% by weight, relative to the total weight of the emulsion.

[0134] The emulsion according to the invention may consist substantially of, or be a combination of, at least one organic peroxide, at least one emulsifier, at least two antifreeze agents, and water, and optionally one or more additives as described above. The term "emulsion substantially composed of the ingredients" means that the total amount of these ingredients accounts for at least 90% by weight, preferably at least 95% by weight, and more preferably at least 98% by weight of the total weight of the emulsion. The expression "composed of..." does not exclude the presence of impurities in the emulsion in trace amounts (e.g., in an amount less than or equal to 1% by weight relative to the total weight of the emulsion), such as impurities introduced with the organic peroxide. Therefore, in some embodiments, the emulsion according to the invention may include an organic solvent in an amount less than or equal to 1% by weight relative to the total weight of the emulsion.

[0135] In other embodiments, the emulsion according to the invention may include an organic solvent, for example, in an amount of less than or equal to 20% by weight relative to the total weight of the emulsion. Hereinafter, the term "organic solvent" refers to an organic solvent with a solubility in water of less than 1% by weight at 0°C. The emulsion according to the invention may consist substantially of or be composed of at least one organic peroxide, at least one emulsifier, a combination of at least two antifreeze agents, water, an organic solvent (preferably in an amount of less than or equal to 20% by weight relative to the total weight of the emulsion), and optionally one or more additives as described above.

[0136] The emulsion according to the invention may consist essentially of or be a combination of at least one organic peroxide, at least one emulsifier, at least two antifreeze agents, and water.

[0137] Preferably, the emulsion according to the invention has a flowability (or flow time) of less than or equal to 200 seconds, more preferably less than or equal to 150 seconds, and even more advantageously less than or equal to 100 seconds at 5°C, as measured by viscosity cup technique. Flowability can be measured according to standard DIN 53211, wherein the viscosity cup diameter is 4 mm and the temperature is 5°C.

[0138] Particularly advantageously, the emulsion according to the invention has an average droplet size of less than or equal to 10 μm, preferably less than or equal to 3 μm. Advantageously, the emulsion according to the invention has a maximum droplet size of less than or equal to 20 μm, more preferably less than or equal to 12 μm, and even more preferably less than or equal to 8 μm. The droplet size (average and maximum) can be determined using conventional means with light scattering techniques. Malvern Master Sizer can be used at room temperature. The equipment performs measurements.

[0139] More advantageously, the emulsion according to the invention has the above-mentioned droplet size during the storage period, preferably at least three months, more preferably at least six months.

[0140] Preferably, the concentration of organic peroxides in the emulsion is uniform. The term "uniform concentration" means that the difference in peroxide concentration between the top and bottom of the emulsion is less than 3% (mass percentage). The concentration of organic peroxides can be measured by HPLC using a sample taken from the top of the emulsion and another sample taken from the bottom of the emulsion.

[0141] More advantageously, the emulsion according to the invention is uniform during the storage period, preferably at least three months, more preferably at least six months.

[0142] Emulsion preparation

[0143] The present invention also relates to a method for preparing an emulsion according to the present invention.

[0144] The preparation method according to the invention includes the step of mixing at least one organic peroxide, at least one emulsifier, a combination of at least two antifreeze agents, and water. This step may further include mixing the above with other components of the emulsion, such as with one or more additives (e.g., one or more plasticizers), as described in the preceding section, when the emulsion contains other components. Mixing may be carried out in one step (all components are added to the mixture simultaneously) or in several steps (a premix of some components is first prepared, and then other components are added).

[0145] The method also includes the step of emulsifying the mixture. The mixing and emulsification of the emulsion components can be performed simultaneously. Alternatively, the emulsification step can be performed sequentially after the first step of mixing the emulsion components.

[0146] The emulsion according to the invention can be prepared by dispersing at least an emulsifier and an antifreeze agent, and optionally one or more additives, in water to obtain a homogeneous aqueous phase, then adding one or more organic peroxides to the aqueous phase, and then emulsifying the entire emulsification step at a temperature preferably below 5°C, and more preferably below -5°C, to limit premature degradation of the peroxides. Alternatively, the emulsifier, or one or more of the emulsifiers, may be dissolved in the organic peroxide before being added to the aqueous phase.

[0147] The above steps can be performed in the specific order described above or in a different order.

[0148] The temperature for emulsion preparation is not critical, but it must be low enough to avoid the high decomposition rate of the organic peroxide, which would lead to titer loss. The chosen temperature depends on the organic peroxide. For example, a temperature of -15 to 10°C, preferably -10 to 5°C. Preferably, the mixing and emulsification steps are carried out at the same temperature, preferably within the above range.

[0149] Deionized water or distilled water is preferred for preparing aqueous emulsions.

[0150] The emulsification step of the method according to the invention is preferably carried out using a high-shear mixer to optimally separate and / or homogenize the peroxides in the aqueous phase. Examples that may be mentioned include mechanically rotating blades and anchor agitators, impeller agitators (i.e., one or more agitators mounted on a common shaft), and turbine agitators (i.e., agitators including baffles attached to a mixing vessel or adjacent agitator components). Colloidal mills and homogenizers may also be used.

[0151] According to a variation of the method according to the invention, an ultrasonic mixer or a rotor-stator mixer can be used for emulsification.

[0152] After emulsion preparation, the steps of pumping and introducing the emulsion into the polymerization reactor should generally be performed as quickly as possible. Therefore, the peroxide emulsion should advantageously have a low viscosity. Thus, the organic peroxide emulsion according to the invention preferably has a viscosity of -10°C and 100s immediately after preparation. -1 The dynamic viscosity range at a shear rate of less than or equal to 850 mPa·s, more preferably less than or equal to 700 mPa·s, and even more preferably less than or equal to 500 mPa·s (e.g., according to standard DIN 53019, using a device of the Haake VT550 type viscometer, at -10°C and for 100 s). -1 (Shear rate measurement of viscosity).

[0153] Their flowability, as measured by the viscosity cup technique, is advantageously less than or equal to 200 seconds, more preferably less than or equal to 150 seconds, and even more advantageously less than or equal to 100 seconds (e.g., measured according to standard DIN 53211, where the viscosity cup diameter is 4 mm and the temperature is 5 °C).

[0154] The average droplet size of the emulsion is preferably less than or equal to 10 μm, more preferably less than or equal to 3 μm. Advantageously, the maximum droplet size of the emulsion is less than or equal to 20 μm, more preferably less than or equal to 12 μm, and even more preferably less than or equal to 8 μm. The droplet size (average and maximum) can be determined using conventional methods with light scattering techniques, and can be achieved at room temperature using the Malvern Master Sizer. The equipment performs measurements.

[0155] use

[0156] The present invention also relates to the use of the above-mentioned emulsion in the polymerization or copolymerization of one or more olefinic unsaturated monomers, particularly one or more vinyl monomers, preferably halogenated vinyl monomers, and more preferably vinyl chloride.

[0157] Examples of olefinic unsaturated monomers that can be used in this invention include acrylates, vinyl esters, halogenated vinyl monomers, vinyl ethers, butadiene, and / or aromatic vinyl compounds such as styrene.

[0158] Preferably, the olefinic unsaturated monomer is selected from halogenated vinyl monomers (i.e., halogenated vinyl monomers), and more preferably, the olefinic unsaturated monomer is vinyl chloride.

[0159] The present invention also relates to a method for preparing a halogenated vinyl polymer, comprising the steps of polymerization or copolymerization of one or more olefinically unsaturated monomers in the presence of the above-described emulsion. The olefinically unsaturated monomers may be as described above, and more preferably vinyl chloride. The prepared halogenated vinyl polymer is preferably poly(vinyl chloride).

[0160] The polymerization of olefinic unsaturated monomers, preferably vinyl chloride monomers, is advantageously carried out in a suspension, preferably at an initial temperature in the range of 45°C to 70°C.

[0161] The emulsion can be added directly to the polymerization reactor, or it can be premixed with other organic peroxides, water, polyvinyl alcohol and / or other additives before being introduced into the polymerization reactor.

[0162] polymer

[0163] Another subject of the invention relates to halogenated vinyl polymers, which are obtained (or can be obtained) by polymerizing at least one olefinically unsaturated monomer as described above in the presence of an emulsion according to the invention. The polymerization can be as described in the preceding section.

[0164] Preferably, the present invention relates to poly(vinyl chloride) obtained (or available) by polymerizing vinyl chloride in the presence of an emulsion according to the invention.

[0165] The present invention also relates to halogenated vinyl polymers obtained (or obtainable) by the above preparation method.

[0166] This halogenated vinyl polymer has the advantage of having a low hard particle content. The hard particle content can be determined as described in O. Leachs’ article in Kunststoffe, Vol. 50 (4), 1960, pp. 227-234.

[0167] Example

[0168] The following examples illustrate the invention but are not intended to limit it.

[0169] The following emulsions were prepared (the amounts shown in the table below are expressed as a percentage of the total weight of the emulsion):

[0170] [Table 1]

[0171] Emulsion Number 1 2 3 4 5 6 PVA 0.60 0.60 0.60 0.60 Surfaline CS25 0.30 0.30 0.30 0.30 Span 80 0.80 0.80 Tween 80 0.80 0.80 ethanol 15.70 12.00 9.00 9.5 15 Propane-1,2-diol 20.60 4.80 8.25 6.5 6.5 Luperox 223 60.0 59.9 59.9 59.9 Luperox 11M75 40.0 40.0 softened water qs 100 qs 100 qs 100 qs 100 qs 100 qs 100

[0172] [Table 2]

[0173] Emulsion Number 7 8 9 10 11 12 Surfaline R20 1.2 1.2 1.2 1.2 1.2 1.2 ethanol 9.5 14.2 11.1 13.0 20.4 9.5 Propane-1,2-diol 4.7 3.1 7.0 9.5 4.8 Luperox 223 59.5 59.9 59.9 60.4 60.4 60.4 softened water qs 100 qs 100 qs 100 qs 100 qs 100 qs 100

[0174] [Table 3]

[0175]

[0176]

[0177] qs 100 = Amount sufficient to reach 100% of the emulsion weight.

[0178] The properties of the compounds used are as follows:

[0179] -Luperox 223: Bis(2-ethylhexyl) peroxide dicarbonate;

[0180] -Luperox 11M75: tert-butyl peroxypentanoate;

[0181] -Luperox 610: 3-hydroxy-1,1-dimethylbutyl peroxyneodecanoate;

[0182] -Surfaline CS25: Ethoxylated (25OE)C 16 -C 18 Alcohol-based nonionic surfactants;

[0183] -Surfaline OC 23: Ethoxylated (23OE) cetyl alcohol nonionic surfactant;

[0184] -Surfaline R20: Ethoxylated (20OE) castor oil nonionic surfactant;

[0185] -Span 80: A nonionic surfactant consisting of dehydrated sorbitan monooleate;

[0186] -Tween 80: Polyethoxylated dehydrated sorbitan monooleate nonionic surfactant;

[0187] -PVA: Polyvinyl acetate (Alcotex 72.5) with a degree of hydrolysis of 72.5 mol%.

[0188] Emulsions 4, 5, 7, 12, 13, 14 and 17 correspond to emulsions according to the present invention, and emulsions 1, 2, 3, 6, 8, 9, 10, 11, 15 and 16 are comparative emulsions.

[0189] The preparation of the emulsion is as follows.

[0190] In the reactor, the aqueous phase containing emulsifier (except Span 80), antifreeze, and water was stirred at 500 to 1000 rpm using a spiral stirrer (IKARW 20) equipped with an anchor rod, and maintained at -5°C for 5 minutes. Span 80 was then added to the organic peroxide at -5°C with stirring, and the mixture was stirred for 5 minutes.

[0191] Add the organic peroxide (Span 80 if appropriate) gradually to the reactor containing the aqueous phase. Continue stirring at 2000 rpm for 3 minutes. Then, vigorously stir the mixture at 9500 rpm for two minutes using an Ultra Turrax S-25N 18G mixer, followed by stirring with a paddle at 1000 rpm for one minute. Each emulsion produces a total of 200g.

[0192] Then transfer the emulsion to a plastic container, close the container, and store the emulsion at -20°C for the specified time.

[0193] The flow time at 5°C (viscosity cup at 5°C), the average and maximum droplet sizes (by volume) over a period of 4 or 6 months, and the concentrations of organic peroxides at the top and bottom of the aqueous emulsion phase (by weight percentage relative to the total weight of the aqueous phase) were determined, as shown below.

[0194] Flow time was measured using a consistency cup according to the standard DIN 53211 (viscosity cup diameter: 4 mm), which is well known to those skilled in the art. Measurements were taken on 100 g of emulsion after conditioning at +5°C. Flow time measurements are expressed in seconds and are accurate to ±10% of the indicated value.

[0195] The average and maximum droplet sizes were determined using conventional methods with light scattering techniques. Malvern Mastersizer was used at room temperature. The equipment performs measurements. The accuracy of the average droplet size and the maximum droplet size is ±0.5 μm (micrometers).

[0196] After storage at -20°C for 6 months, samples were taken from the top of the emulsion (first centimeter below the emulsion surface) and from the bottom of the emulsion (first centimeter from the bottom of the emulsion) and analyzed to determine the concentration of organic peroxides. The concentration of organic peroxides in the aqueous phase was determined on a Waters H-class UPLC system with an accuracy of ±1%.

[0197] The results are shown in the table below.

[0198] [Table 4]

[0199]

[0200]

[0201] [Table 5]

[0202]

[0203]

[0204] [Table 6]

[0205]

[0206]

[0207] It was found that emulsion 4 according to the invention, after 4 months of storage, has a smaller average droplet size and a smaller maximum droplet size than comparative emulsions comprising greater than 9.5% by weight of ethanol (emulsions 1 and 3) or comprising only propane-1,2-diol (emulsion 2). The smaller droplet size provides an advantage in applications during polymerization. The polymer will have better quality and, in particular, will have fewer hard particles.

[0208] It should also be noted that the emulsion 5 according to the invention is more stable than the contrast emulsion 6, which undergoes phase separation after about one month of storage. In contrast, emulsion 5 remains stable for a period of at least six months and maintains a small average droplet size and maximum droplet size throughout this period.

[0209] Emulsions 7 and 12 according to the invention remain stable for at least a period of 6 months, maintaining small average and maximum droplet sizes. Emulsion 12 also exhibits a uniform concentration of organic peroxides at both the top and bottom of the emulsion after 6 months. Compared to comparative emulsions 8 and 9, emulsions 7 and 12 exhibit smaller average and maximum droplet sizes from the first month of storage and particularly after 6 months of storage. Furthermore, comparative emulsions 10 and 11 are less stable, with emulsion 11 stratifying after 1 month and emulsion 10 after 5 to 6 months.

[0210] Finally, emulsions 15 and 16 were found to be slightly stable, with stratification observed in emulsion 16 from the first month onwards, and in emulsion 15 after 3 months. Emulsions 13, 14, and 17 according to the invention, for their part, remained stable for at least a period of 6 months, maintaining small average and maximum droplet sizes during this time. Their organic peroxide concentrations at the top and bottom of the emulsions were uniform after 6 months.

[0211] The emulsion according to the present invention also has a sufficiently low flow time after preparation.

Claims

1. Organic peroxide emulsions, including: - At least one organic peroxide; - At least one emulsifier, comprising at least one nonionic surfactant comprising at least one fatty chain and / or a protective colloid; - A combination of at least two antifreeze agents, comprising a first antifreeze agent composed of ethanol in an amount less than or equal to 9.5% by weight relative to the total weight of the emulsion, and at least one second antifreeze agent; and - water, The at least one nonionic surfactant comprising at least one fatty acid chain is selected from oxoalkylated fatty acids, oxoalkylated vegetable or animal oils, polysorbates, alkyl glucosides, oxoalkylated alkyl glucosides, and mixtures thereof.

2. The emulsion of claim 1, wherein the at least one second antifreeze agent is an alcohol.

3. The emulsion of claim 2, wherein the at least one second antifreeze agent is selected from monools, diols, triols, and mixtures thereof.

4. The emulsion according to any one of claims 1 to 3, wherein the at least one second antifreeze agent is selected from methanol, ethylene glycol, 2-propanol, 1-propanol, propane-1,2-diol, propane-1,3-diol, glycerol, butane-1-ol, butane-2-ol, butane-1,3-ol, butane-1,4-diol, diethylene glycol, and mixtures thereof.

5. The emulsion according to any one of claims 1 to 3, wherein the at least one second antifreeze agent comprises propane-1,2-diol.

6. The emulsion of claim 5, wherein the at least one second antifreeze agent is composed of propane-1,2-diol.

7. The emulsion according to any one of claims 1 to 3, wherein the second antifreeze is present in an amount of 3% to 17% by weight relative to the total weight of the emulsion.

8. The emulsion of claim 7, wherein the second antifreeze is present in an amount of 3% to 9% by weight.

9. The emulsion of claim 8, wherein the second antifreeze is present in an amount of 3% to 8% by weight.

10. The emulsion according to any one of claims 1 to 3, wherein a combination of at least two antifreeze agents is present in an amount of 10% to 40% by weight relative to the total weight of the emulsion.

11. The emulsion of claim 10, wherein the combination of at least two antifreeze agents is present in an amount of 15% to 25% by weight.

12. The emulsion according to any one of claims 1 to 3, wherein the at least one organic peroxide is selected from dicarbonate peroxide, peroxide ester, diacyl peroxide, and combinations thereof.

13. The emulsion according to any one of claims 1 to 3, wherein the at least one organic peroxide is selected from tert-amyl peroxypentanoate, tert-butyl peroxypentanoate, tert-butyl peroxydecanoate, tert-amyl peroxydecanoate, 3-hydroxy-1,1-dimethylbutyl peroxydecanoate, cumyl peroxydecanoate, bis(2-ethylhexyl) peroxydicarbonate, bis(3,5,5-trimethylhexanoyl) peroxide, and mixtures thereof.

14. The emulsion according to any one of claims 1 to 3, wherein the at least one organic peroxide is present in an amount of 40% to 80% by weight relative to the total weight of the emulsion.

15. The emulsion of claim 14, wherein the at least one organic peroxide is present in an amount of 45% to 60% by weight.

16. The emulsion according to any one of claims 1 to 3, wherein the at least one emulsifier comprises at least one protective colloid agent.

17. The emulsion of claim 16, wherein the at least one emulsifier comprises at least one polyvinyl alcohol and / or hydrolyzed polyvinyl acetate.

18. The emulsion according to any one of claims 1 to 3, wherein it is free of polyvinyl alcohol and hydrolyzed polyvinyl acetate.

19. The emulsion according to any one of claims 1 to 3, wherein the at least one emulsifier comprises at least one nonionic surfactant including at least one fatty chain and optionally at least one protective colloid agent.

20. The emulsion of claim 19, wherein the at least one protective colloid is at least one polyvinyl alcohol and / or hydrolyzed polyvinyl acetate.

21. A method for preparing an emulsion as described in any one of claims 1 to 20, comprising the following steps: - A mixture of the at least one organic peroxide, the at least one emulsifier, the combination of the at least two antifreeze agents, and water; and - To emulsify the mixture.

22. Use of the emulsion according to any one of claims 1 to 20, wherein it is used for the polymerization or copolymerization of one or more olefinic unsaturated monomers.

23. The use as described in claim 22, wherein the one or more olefinic unsaturated monomers are vinyl monomers.

24. The use as described in claim 22, wherein the one or more olefinic unsaturated monomers are halogenated vinyl monomers.

25. The use as described in claim 22, wherein one or more olefinically unsaturated monomers are vinyl chloride.

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