FR3121683A1 - Composition comprising at least one aromatic peroxide and at least one ketone peroxide - Google Patents

Abstract

The present invention relates to a composition comprising at least one aromatic peroxide comprising at least one aromatic nucleus and at least one peroxo function in its structure, as defined below, and at least one ketone peroxide.

Description

Composition comprising at least one aromatic peroxide and at least one ketone peroxide

FIELD OF THE INVENTION

The present invention relates to a composition comprising at least one aromatic peroxide comprising at least one aromatic ring and at least one peroxo function in its structure, as defined below, and at least one ketone peroxide.

The invention also relates to the use of said composition in order to prepare a polymer, preferably styrenic polymers, or a polymer resin, in particular a polymer ester resin, said polymer ester resin preferably being chosen from the group consisting of unsaturated polyester, acrylic resin, methacrylic resin and vinyl ester resin.

The invention also relates to the use of at least one ketone peroxide for improving the color stability of a composition comprising at least one aromatic peroxide having at least one aromatic nucleus and at least one peroxo function in its structure such as defined below.

BACKGROUND OF THE INVENTION

Aromatic peroxides are nowadays often used as radical initiators in various polymerization reactions, such as for the synthesis of styrenic resins, vinyl ester resins or polyacrylates, for example a poly(meth)acrylate having grafted aromatic rings , or as hardening agents for the preparation of thermosetting polyesters, in particular unsaturated polyester resins which can be used for the manufacture of artificial marble products, gel coats, marine craft, polymer concrete and others.

Aromatic peroxides are well known in the trade and can be selected from the family of aromatic peresters, in particular perbenzoates, such as tert-butyl peroxybenzoate (denoted TBPB) sold for example under the name Luperox® P, peralkylates of aryl and aromatic diperesters, the family of aryl-alkyl peroxides, such as dicumyl peroxide, the family of aryl hydroperoxides such as cumene hydroperoxide, and the family of aromatic diacyl peroxides such as of di(2,4-dichloro benzoyl).

However, one of the major disadvantages of the aforementioned aromatic peroxides is that they are usually subject to color transformation after a certain period of time at room temperature or recommended storage temperature conditions (i.e. between 8 and 30°C) under standard storage conditions. In particular, it has been pointed out that the color of said aromatic peroxides increases steadily or even sometimes flies away over a relatively short period of time, for example the color of tert-butyl peroxybenzoate can increase over a period of 21 days, during storage. This indicates that the aforementioned aromatic peroxides may experience color stability issue during storage, even in the dark.

As a result, this color stability issue can reduce the shelf life of aromatic peroxides, sometimes causing manufacturers of the subject polymer resins to use them sooner than expected before they develop significant and irreversible color change. Indeed, there is a probable risk that the said colored impurities of the aromatic peroxides tint the polymers or the polymeric resins during their preparations, which can prove to be a significant problem depending on their intended applications.

In particular, the production of polymers or polymer resins that are unintentionally colored due to the coloring provided by aromatic peroxides can easily be misinterpreted by some users to mean that said polymers or polymer resins are of poor quality. By way of example, it can be assumed that said polymers or polymer resins produced have been subjected to photo-oxidation or photo-degradation which has modified their natural appearance and properties.

More generally, the lack of color stability of said aromatic peroxides during storage can affect the appearance of the targeted polymer compounds and alter the general appearance of the final product. It can also lead to a misinterpretation of the quality of said polymer compounds and of the products obtained from them.

Additionally, this coloring can make it more difficult to manufacture polymer compounds that are expected to have specific light color characteristics dictated by their industrial applications, for example LDPE blister pack applications.

In addition, in some cases, this coloring can make the subsequent addition of colorants designed to impart a specific color to the final appearance of the polymer compounds more cumbersome. Indeed, the polymer compounds produced can sometimes present a color due to the aromatic peroxides which does not correspond to the dyes which must be added.

Therefore, from a commercial point of view, the risks of color transfer of the aforementioned aromatic peroxides can represent an obstacle to the economic value of the polymers and polymer resins produced.

The development of a color in a composition comprising aromatic peroxides can also interfere with the possible presence of colored dyes which have been added to said composition on purpose, for example as a visual aid to help the operator during his process.

Thus, there remains a real need to provide compositions comprising aromatic peroxides which are capable of exhibiting color stability over time under the recommended storage conditions in order to mitigate the risks of color transfer to the targeted polymer compounds previously detailed. .

In particular, one of the objectives of the present invention is to minimize the color development of aromatic peroxides during storage, especially at room temperature, in order to be able to use them effectively to manufacture said polymer compounds without negatively impacting their appearance.

More specifically, another object of the present invention is to slow down the color increase of aromatic peroxides during their storage period.

DESCRIPTION OF THE INVENTION

The present invention results in particular from the unexpected discoveries, by the inventors, that the use of at least one ketone peroxide is capable of improving the color stability over time of at least one aromatic peroxide as defined below. afterwards (that is to say to slow down the evolution of the color of said aromatic peroxides) and also to reduce the coloring due to said aromatic peroxides.

For this reason, the present invention relates to a composition comprising:
a) at least one aromatic peroxide comprising at least one aromatic nucleus and at least one peroxo function -OO- in its structure; the aromatic ring being linked to said peroxo function by a covalent bond or an alkyl group comprising from 1 to 20 carbon atoms;
the aromatic peroxide being present in said composition at a concentration ranging from 30 to 99.9% by weight relative to the total weight of the composition,
b) at least one ketone peroxide being at a concentration ranging from 0.1 to 30% by weight relative to the total weight of the composition.

The composition of the present invention exhibits better color stability over time under standard storage conditions than a composition comprising only the aforementioned aromatic peroxide(s), especially at room temperature. , especially in the dark.

In more detail, the composition according to the present invention exhibits a significantly lower APHA color value than the same composition comprising only the aforementioned aromatic peroxide(s) over a period of time of at least 5 days, in particular at least 15 days, especially at least 20 days, preferably at least 30 days, more preferably at least 50 days and even more particularly over at least 90 days, under standard storage conditions, especially at room temperature, and especially in the dark.

According to the present invention, the expression "room temperature" represents a temperature range from 0°C to 50°C, preferably from 10°C to 40°C, more preferably from 15°C to 30°C, even more preferably from 20°C to 30°C.

According to the present invention, the expression “in the dark” means that the composition is protected from light, and in particular is protected from ultraviolet (UV) radiation.

According to the present invention, the APHA color is a color standard bearing the name of the American Public Health Association and defined by the ASTM D1209 standard, and more precisely ASTM D1209-05 (2011). APHA color is a color scale, sometimes also called "yellowness index", which is used to assess the quality of samples that are pale to yellowish in color. APHA color is measured using a colorimeter with a standard range of 0 to 1000 APHA.

The color of the composition according to the present invention can be evaluated with a spectral colorimeter such as that sold under the name LICO 620 by the company Hach.

In other words, the addition of at least one ketone peroxide is capable of decreasing or stabilizing the APHA color value of the aforementioned aromatic peroxide(s).

The color stability of the composition of the present invention helps to minimize the chances that there will be unwanted color resulting from the aromatic peroxides, due to their shelf life, on the targeted polymeric compounds.

Accordingly, the composition of the present invention can effectively be used for the preparation of a polymer, in particular polystyrene, or polymer resins, preferably a polymer ester resin, without changing their appearance, i.e. without tinting them unintentionally.

More specifically, the use of at least one ketone peroxide is capable of significantly slowing down the color evolution of aromatic peroxides over time, especially at room temperature.

This also means that the addition of at least one ketone peroxide is able to extend the pot life of said aromatic peroxides in applications, especially at room temperature.

Accordingly, the use of at least one ketone peroxide is capable of restoring the economic appeal of aromatic peroxides since they can be stored under standard conditions for extended periods of time without experiencing significant color development. and unacceptable.

The present invention also relates to a process for the preparation of the aforementioned composition comprising the mixture of at least one aromatic peroxide, as defined above, and at least one ketone peroxide.

As mentioned previously, the composition exhibits improved color stability.

The invention also relates to the use of a composition as defined above in order to prepare a polymer, preferably styrenic polymers, or a polymer resin, in particular a polymer ester resin, said polymer ester resin preferably being chosen from the group consisting of unsaturated polyester resin, acrylic resin, methacrylic resin and vinyl ester resin, more preferably selected from the group consisting of unsaturated polyester resin and vinyl ester resin.

In detail, the composition of the present invention can be effectively used for the polymerization reaction of styrenic polymers, vinyl ester resins or poly(meth)acrylates, or as a curing agent for the preparation of thermosetting polyesters, in particular unsaturated polyester resins.

Another aspect of the present invention is the use of at least one ketone peroxide to improve the color stability of at least one aromatic peroxide, in particular at room temperature.

Preferably, one of the aspects of the present invention consists in using at least one ketone peroxide in order to slow down the evolution of color of aromatic peroxides.

Other objects and characteristics, aspects and advantages of the invention will appear even more clearly on reading the description and the example which follow.

In the text below, and unless otherwise indicated, the limits of a range of values are included in this range, in particular in the expressions “between” and “ranging from … to …”.

Moreover, the expression “at least one” used in the present description is equivalent to the expression “one or more”.

The term "polymerization" encompasses both homo- and copolymerization of one or more of the unsaturated monomers involved.

As provided herein, the term "comprising" has the meaning of "including" or "containing", which means that when an object "comprises" one or more elements, other elements than those mentioned may also be included in the object. On the other hand, when an object is said to "consist of" one or more elements, the object is limited to the elements listed and cannot include other elements than those mentioned.

The represents measurements of APHA values as a function of time for compositions A and B to F shown in Table 1 at a temperature of 40°C.

The represents measurements of APHA values as a function of time for compositions A1 and B1 to G1 illustrated in Table 2 at a temperature of 40°C.

The represents the APHA values as a function of time for compositions A2 and B2 to H2 shown in Table 3 measured at 40°C.

Composition

As previously detailed, the composition according to the present invention comprises:
a) at least one aromatic peroxide comprising at least one aromatic nucleus and at least one peroxo function -OO- in its structure; the aromatic ring being linked to said peroxo function by a covalent bond or an alkyl group comprising from 1 to 20 carbon atoms;
the aromatic peroxide being present in said composition at a concentration ranging from 30 to 99.9% by weight relative to the total weight of the composition,
b) at least one ketone peroxide being at a concentration ranging from 0.1 to 30% by weight relative to the total weight of the composition.

aromatic peroxide

The aromatic ring of the aromatic peroxide can be substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably an alkyl radical C ₁ to C ₁₀ linear or branched, especially a C ₁ to C ₄ alkyl radical, or one or more halogen atoms.

Preferably, the aromatic peroxide comprises at least one benzene ring. The benzene ring is preferably connected to said peroxo function by a covalent bond or an alkyl group comprising from 1 to 20 carbon atoms, preferably from 1 to 10 carbon atoms, more preferably from 1 to 2 carbon atoms, even more preferably 1 carbon atom.

Preferably, the aromatic peroxide comprises at least one benzene ring and at least one peroxo -O-O- function in its structure; the benzene ring being linked to said peroxo function by not more than two carbon atoms, even more preferably not more than one carbon atom.

According to the present invention, the expression "the benzene ring being connected to the said peroxo function by no more than two carbon atoms" means that the benzene ring is connected to the -O-O- function of the aromatic peroxide by a covalent bond or a group alkyl which does not have more than two carbon atoms (an alkyl group of two carbon atoms being included).

According to the present invention, the expression "the benzene ring being connected to said peroxo function by not more than one carbon atom" means that the benzene ring is connected to the -O-O- function of the aromatic peroxide by a covalent bond or a an alkyl group which does not contain more than one carbon atom (one carbon atom being included).

Preferably, the aromatic peroxide comprises at least one benzene ring and at least one peroxo -OO- function in its structure; the benzene ring being linked to said peroxo function by a covalent bond or an alkyl group comprising from 1 to 2 carbon atoms, even more preferably 1 carbon atom; the benzene ring being optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms.

Preferably, the aromatic peroxide as defined above is liquid at ambient temperature. The aromatic peroxide can be selected from the group consisting of aromatic peresters, aryl-alkyl peroxides, aryl hydroperoxides, aromatic diacyl peroxides and mixtures thereof.

Preferably, the aromatic peroxide can be selected from the group consisting of aromatic peresters.

Preferably, the aromatic peroxide comprises at least one benzene ring and at least one peroxo -OO- function in its structure; the benzene ring being linked to said peroxo function by a covalent bond or an alkyl group comprising from 1 to 2 carbon atoms, even more preferably 1 carbon atom; the benzene ring being optionally substituted by a linear or branched C ₁ to C ₄ alkyl radical and/or one or more halogen atoms; and the aromatic being selected from the group consisting of aromatic peresters, aryl-alkyl peroxides, aryl hydroperoxides, aromatic diacyl peroxides and mixtures thereof; especially aromatic peresters.

The aromatic peroxide selected from aromatic peresters is preferably selected from the group consisting of perbenzoates, aryl peralkylates, aromatic diperesters and mixtures thereof.

Advantageously, the aromatic peroxide is chosen from the group consisting of perbenzoates.

Preferably, the aromatic peroxide has the following formula (I):

[Chem 1]
R ₁ -OOR ₂
(I)
in which
● R ₁ represents:
- a group –C(=O)R' ₁ , in which R' ₁ denotes an aryl group having from 3 to 30 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or several halogen atoms, or
- a linear or branched C ₁ to C ₂₀ alkyl radical ending in an aryl group having from 3 to 30 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more carbon atoms halogen, or
- a –CR'1 group, in which R'1 denotes an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C1 to C10 alkyl radical and/or one or more halogen atoms;
● R ₂ represents:
- a linear or branched C ₁ to C ₂₀ alkyl radical,
- an aryl group having from 3 to 30 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms,
- a group -R ₃ OOR ₄ , in which R ₃ represents a linear or branched C ₈ to C ₂₀ alkyl radical, preferably a C ₈ to C ₁₀ alkyl radical, and R ₄ represents a group –C(=O ) R' ₄ in which R' ₄ denotes an aryl group having from 3 to 30 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms,
- a linear or branched C ₁ to C ₂₀ alkyl radical ending in an aryl group having from 3 to 30 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more carbon atoms 'halogen,
- a group –C(=O)R' ₂ , in which R' ₂ denotes an aryl group having from 3 to 30 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or several halogen atoms, or
- a hydrogen atom.
Preferably, the aromatic peroxide has the following formula (I):
[Chem. 2]
R ₁ -OOR ₂
(I)
in which :
● R ₁ represents:
- a group -C(=O)R' ₁ , in which R' ₁ denotes an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or several halogen atoms, or
- a linear or branched C ₁ to C ₂₀ alkyl radical ending in an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, optionally substituted by a peroxy group, and/or one or more halogen atoms; Where
- a –CR' ₁ group, in which R' ₁ denotes an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms ,
● R ₂ represents:
- a linear or branched C ₁ to C ₂₀ alkyl radical,
- an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms,
- a group -R ₃ OOR ₄ , in which R ₃ represents a linear or branched C ₈ to C ₂₀ alkyl radical, preferably a C ₈ to C ₁₀ alkyl radical, and R ₄ represents a group –C(=O ) R' ₄ in which R' ₄ denotes an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms,
- a linear or branched C ₁ to C ₂₀ alkyl radical ending in an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more carbon atoms 'halogen,
- a group –C(=O)R' ₂ , in which R' ₂ denotes an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or several halogen atoms, or
- a hydrogen atom.

Preferably, the aromatic peroxide has the following formula (I):

[Chem 3]
R ₁ -OOR ₂
(I)
in which :
● R ₁ represents:
- a group –C(=O)R' ₁ , in which R' ₁ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms, preferably chlorine atoms, or
- a linear or branched C ₁ to C ₂₀ alkyl radical terminating in a benzene ring which is optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms, preferably chlorine atoms;
● R ₂ represents:
- a linear or branched C ₁ to C ₂₀ alkyl radical,
- a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms, preferably chlorine atoms,
- a group -R ₃ OOR ₄ , in which R ₃ represents a linear or branched C ₈ to C ₂₀ alkyl radical, preferably a C ₈ to C ₁₀ alkyl radical, and R ₄ represents a group –C(=O ) R' ₄ in which R' ₄ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms,
- a linear or branched C ₁ to C ₂₀ alkyl radical ending in a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms,
- a group –C(=O)R' ₂ , in which R' ₂ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms, preferably chlorine atoms,
- a hydrogen atom.

Preferably, R ₁ represents:
- a group –C(=O)R' ₁ , in which R' ₁ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms, or
- a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a branched C ₁ to C ₁₀ alkyl radical, which terminates in a benzene ring which is optionally substituted by a linear C ₁ to C ₁₀ alkyl radical or branched, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms.

Preferably, R ₂ represents:
- a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₅ alkyl radical, more preferably a branched C ₁ to C ₅ alkyl radical,
- a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a linear or branched C ₁ to C ₄ alkyl radical and/or one or more halogen atoms, preferably chlorine atoms ,
- a group -R ₃ OOR ₄ , in which R ₃ represents a linear or branched C ₈ to C ₂₀ alkyl radical, preferably a C ₈ to C ₁₀ alkyl radical, and R ₄ represents a group –C(=O )R' ₄ in which R' ₄ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms , preferably chlorine atoms,
- a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a branched C ₁ to C ₁₀ alkyl radical, which ends in a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms,
- a group –C(=O)R' ₂ , in which R' ₂ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms,
- a hydrogen atom.

Preferably, in formula (I):
● R ₁ represents:
- a group –C(=O)R' ₁ , in which R' ₁ is a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms, or
- a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a branched C ₁ to C ₁₀ alkyl radical, which terminates in a benzene ring which is optionally substituted by a linear C ₁ to C ₁₀ alkyl radical or branched, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms,
● R ₂ represents:
- a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₅ alkyl radical, more preferably a branched C ₁ to C ₅ alkyl radical,
- a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a linear or branched C ₁ to C ₄ alkyl radical and/or one or more halogen atoms, preferably chlorine atoms ,
- a group -R ₃ OOR ₄ , in which R ₃ represents a linear or branched C ₈ to C ₂₀ alkyl radical, preferably a C ₈ to C ₁₀ alkyl radical, and R ₄ represents a group –C(=O )R' ₄ in which R' ₄ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms ,
- a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a branched C ₁ to C ₁₀ alkyl radical, which ends in a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms,
- a group –C(=O)R' ₂ , in which R' ₂ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms,
- a hydrogen atom.

Preferably, the aromatic peroxide has the following formula (I):

[Chem 4]
R ₁ -OOR ₂
(I)
in which :
● R ₁ represents:
- a group –C(=O)R' ₁ , in which R' ₁ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms,
● R ₂ represents:
- a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₅ alkyl radical, more preferably a branched C ₁ to C ₅ alkyl radical,
- a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a linear or branched C ₁ to C ₄ alkyl radical, even more preferably a branched C ₁ to C ₄ alkyl radical, and/ or one or more halogen atoms, preferably chlorine atoms,
- a group -R ₃ OOR ₄ , in which R ₃ represents a linear or branched C ₈ to C ₂₀ alkyl radical, preferably a C ₈ to C ₁₀ alkyl radical, and R ₄ represents a group –C(=O )R' ₄ in which R' ₄ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms , preferably chlorine atoms,
- a group –C(=O)R' ₂ , in which R' ₂ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms.

Preferably, the aromatic peroxide has the following formula (I):

[Chem 5]
R ₁ -OOR ₂
(I)
in which :
● R ₁ represents:
- a group –C(=O)R' ₁ , in which R' ₁ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms,
● R ₂ represents:
- a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₅ alkyl radical, more preferably a branched C ₁ to C ₅ alkyl radical.

Preferably, the aromatic peroxide is selected from the group consisting of t-butyl peroxybenzoate, such as that sold under the name Luperox® P, cumyl peroxyneoheptanoate, such as that sold under the name Luperox® 288, cumyl peroxyneodecanoate, such as than that sold under the name Luperox® 188, 2,5-dimethyl-2,5-(dibenzoylperoxy)hexane, such as Luperox® 118, tert-butyl-cumyl peroxide, such as that sold under the name Luperox® 801, dicumyl peroxide, such as that sold under the name Luperox® DCP, cumene hydroperoxide, such as that sold under the name Luperox® CU80, di(2,4-dichloro benzoyl) peroxide, such as that under the name Luperox® DCBP, 1,3 1,4-bis-(tert-butylperoxyisopropyl)benzene, such as that under the name Luperox® F, tert-amyl peroxybenzoate, such as Luperox® TAP and mixtures thereof.

Preferably, the aromatic peroxide is selected from the group consisting of t-butyl peroxybenzoate, cumyl peroxyneoheptanoate, cumyl peroxyneodecanoate, 2,5-dimethyl-2,5-(dibenzoylperoxy)hexane, tert-amyl peroxybenzoate, and mixtures of these.

Advantageously, the aromatic peroxide is t-butyl peroxybenzoate.

The aromatic peroxide is present in the composition at a concentration ranging from 30 to 99.9%, preferably from 70 to 99.9%, more preferably ranging from 90 to 99.9% by weight relative to the total weight of the composition .

In particular, the aromatic peroxide is t-butyl peroxybenzoate and is present at a concentration ranging from 30 to 99.9%, preferably from 70 to 99.9%, more preferably ranging from 90 to 99.9% by weight. relative to the total weight of the composition

Ketone peroxide

As provided herein "ketone peroxide" means an organic compound comprising at least one peroxide (-OOH) functional group.

Preferably, the ketone peroxide as defined above is liquid at ambient temperature.

The ketone peroxide is preferably selected from the group consisting of methyl-ethyl-ketone peroxide, methyl-isobutyl-ketone peroxide, 2,4-pentanedione peroxide and mixtures thereof, even more preferably methyl peroxide -ethyl-ketone and methyl-isobutyl-ketone peroxide.

Preferably, the ketone peroxide according to the invention is of the following formula (II):

[Chem 6]
(II) R ₃ CR ₄ (OOH) ₂
in which R ₃ and R _4:
- independently of one another represents a linear or branched C1 to C20 alkyl radical, or
- together form a cyclic group, substituted or unsubstituted, preferably a C4 to C6 cyclic group.

According to a particular embodiment, the ketone peroxide can be in the form of a dimer (having the formula (III) R ₃ R ₄ C(OOH)OOC(OOH)R ₃ R ₄ , R ₃ and R ₄ being as defined previously) or of a trimer (having the formula (IV) R ₃ R ₄ C(OOH)OOCR ₃ R ₄ OOC(OOH)R ₃ R ₄ , R ₃ and R ₄ being as defined previously), preferably a dimer.

Advantageously, the ketone peroxide is chosen from the group consisting of methyl-ethyl-ketone peroxide, such as that sold under the name Luperox® K1 and methyl-isobutyl-ketone peroxide, such as that sold under the name Luperox® K2.

The ketone peroxide is present in the composition at a concentration ranging from 0.1 to 30%, especially ranging from 1 to 29%, preferably ranging from 2 to 25%, more preferably 4 to 20%, even more preferably 5 to 10% by weight, relative to the total weight of the composition.

In particular, the ketone peroxide is methyl-ethyl-ketone peroxide and is present in the composition at a concentration ranging from 0.1 to 30%, especially ranging from 1 to 29%, preferably ranging from 2 to 25% , more preferably 4 to 20%, even more preferably 5 to 10% by weight, based on the total weight of the composition.

Preferably, the composition according to the present invention comprises:
a) at least one aromatic peroxide having the following formula (I)

[Chem 7]
R ₁ -OOR ₂
(I)
in which :
● R ₁ represents:
- a group –C(=O)R' ₁ , in which R' ₁ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms, preferably chlorine atoms, or
- a linear or branched C ₁ to C ₂₀ alkyl radical terminating in a benzene ring which is optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms, preferably chlorine atoms; Where
- a –CR'1 group, in which R'1 denotes an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C1 to C10 alkyl radical and/or one or more halogen atoms,
● R ₂ represents:
- a linear or branched C ₁ to C ₂₀ alkyl radical,
- a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms, preferably chlorine atoms,
- a group -R ₃ OOR ₄ , in which R ₃ represents a linear or branched C ₈ to C ₂₀ alkyl radical, preferably a C ₈ to C ₁₀ alkyl radical, and R ₄ represents a group –C(=O ) R' ₄ in which R' ₄ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms,
- a linear or branched C ₁ to C ₂₀ alkyl radical ending in a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms,
- a group –C(=O)R' ₂ , in which R' ₂ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms, preferably chlorine atoms,
- a hydrogen atom.
the aromatic peroxide being present in said composition at a concentration ranging from 30 to 99.9% by weight relative to the total weight of the composition,
b) at least one ketone peroxide is preferably selected from the group consisting of methyl-ethyl-ketone peroxide, methyl-isobutyl-ketone peroxide, 2,4-pentanedione peroxide and mixtures thereof, preferably methyl ethyl ketone peroxide and methyl isobutyl ketone peroxide, even more preferably methyl ethyl ketone peroxide;
the ketone peroxide being present in said composition at a concentration ranging from 0.1 to 30% by weight relative to the total weight of the composition.

Preferably, the composition according to the present invention comprises:
a) at least one aromatic peroxide having the following formula (I)

[Chem 8]
R ₁ -OOR ₂
(I)
in which :
● R ₁ represents:
- a group –C(=O)R' ₁ , in which R' ₁ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms,
● R ₂ represents:
- a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₅ alkyl radical, more preferably a branched C ₁ to C ₅ alkyl radical,
- a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a linear or branched C ₁ to C ₄ alkyl radical, even more preferably a branched C ₁ to C ₄ alkyl radical, and/ or one or more halogen atoms, preferably chlorine atoms,
- a group -R ₃ OOR ₄ , in which R ₃ represents a linear or branched C ₈ to C ₂₀ alkyl radical, preferably a C ₈ to C ₁₀ alkyl radical, and R ₄ represents a group –C(=O )R' ₄ in which R' ₄ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms , preferably chlorine atoms,
- a group –C(=O)R' ₂ , in which R' ₂ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms;
the aromatic peroxide being present in said composition at a concentration ranging from 30 to 99.9% by weight relative to the total weight of the composition;
b) at least one ketone peroxide is preferably selected from the group consisting of methyl-ethyl-ketone peroxide, methyl-isobutyl-ketone peroxide, 2,4-pentanedione peroxide and mixtures thereof, preferably methyl ethyl ketone peroxide and methyl isobutyl ketone peroxide, even more preferably methyl ethyl ketone peroxide;
the ketone peroxide being present in said composition at a concentration ranging from 0.1 to 30% by weight relative to the total weight of the composition.

Preferably, the composition according to the present invention comprises:
a) at least one aromatic peroxide selected from the group consisting of t-butyl peroxybenzoate, cumyl peroxyneoheptanoate, cumyl peroxyneodecanoate, 2,5-dimethyl-2,5-(dibenzoylperoxy)hexane, tert-butyl-cumyl peroxide, dicumyl peroxide, cumene hydroperoxide, di(2,4-dichlorobenzoyl) peroxide, 1,3 1,4-bis-(tert-butylperoxyisopropyl)benzene, and mixtures thereof, preferably t -butyl;
the aromatic peroxide being present in said composition at a concentration ranging from 30 to 99.9% by weight relative to the total weight of the composition;
b) at least one ketone peroxide is selected from the group consisting of methyl-ethyl-ketone peroxide, methyl-isobutyl-ketone peroxide, 2,4-pentanedione peroxide and mixtures thereof, preferably methyl ethyl ketone and methyl isobutyl ketone peroxide, even more preferably methyl ethyl ketone peroxide;
the ketone peroxide being present in said composition at a concentration ranging from 0.1 to 30% by weight relative to the total weight of the composition.

Preferably, the composition according to the present invention comprises:
a) t-butyl peroxybenzoate being present in said composition at a concentration ranging from 30 to 99.9%, preferably ranging from 70 to 99.9%, more preferably ranging from 90 to 99.9% by weight relative to the total weight of the composition by weight relative to the total weight of the composition;
b) at least one ketone peroxide selected from the group consisting of methyl-ethyl-ketone peroxide and methyl-isobutyl-ketone peroxide; the ketone peroxide being present in said composition at a concentration ranging from 0.1 to 30%, especially ranging from 1 to 29%, preferably ranging from 2 to 25%, more preferably 4 to 20%, even more preferably 5 to 10% by weight, relative to the total weight of the composition.

Advantageously, the composition according to the present invention comprises:
a) t-butyl peroxybenzoate being present in said composition at a concentration ranging from 30 to 99.9% preferably ranging from 90 to 99.9% by weight relative to the total weight of the composition by weight relative to the weight composition total;
b) methyl-ethyl-ketone peroxide being present in said composition at a concentration ranging from 0.1 to 30%, especially ranging from 1 to 29%, preferably ranging from 2 to 25%, more preferably 4 to 20% , even more preferably 5 to 10% by weight, relative to the total weight of the composition.

According to another possibility, the composition according to the present invention comprises:
a) t-butyl peroxybenzoate being present in said composition at a concentration ranging from 30 to 99.9%, preferably ranging from 70 to 99.9%, more preferably ranging from 90 to 99.9% by weight relative to the total weight of the composition by weight relative to the total weight of the composition;
b) methyl-isobutyl-ketone peroxide being present in said composition at a concentration ranging from 0.1 to 30%, especially ranging from 1 to 29%, preferably ranging from 2 to 25%, more preferably 4 to 20% , even more preferably 5 to 10% by weight, relative to the total weight of the composition.

Preferably, the weight ratio between aromatic peroxide and ketone peroxide ranges from 0.001 to 1, preferably from 0.01 to 0.5, even more preferably from 0.05 to 0.1.

Hydrogen peroxide (H ₂ O ₂ )

Preferably, the composition according to the invention also comprises hydrogen peroxide (H ₂ O ₂ ).

Hydrogen peroxide may be present in the composition according to the invention at a concentration ranging from 0.0005 to 3%, preferably ranging from 0.001 to 2%, even more preferably 0.01 to 1.5% by weight, even more preferably 0.1 to 1.5% by weight relative to the total weight of the composition.

Preferably, the composition according to the present invention comprises:
a) at least one aromatic peroxide having the following formula (I):

[Chem 9]
R ₁ -OOR ₂
(I)
in which :
● R ₁ represents:
- a group –C(=O)R' ₁ , in which R' ₁ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms,
● R ₂ represents:
- a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₅ alkyl radical, more preferably a branched C ₁ to C ₅ alkyl radical,
- a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a linear or branched C ₁ to C ₄ alkyl radical, even more preferably a branched C ₁ to C ₄ alkyl radical, and/ or one or more halogen atoms, preferably chlorine atoms,
- a group -R ₃ OOR ₄ , in which R ₃ represents a linear or branched C ₈ to C ₂₀ alkyl radical, preferably a C ₈ to C ₁₀ alkyl radical, and R ₄ represents a group –C(=O )R' ₄ in which R' ₄ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms , preferably chlorine atoms,
- a group –C(=O)R' ₂ , in which R' ₂ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms;
the aromatic peroxide being present in said composition at a concentration ranging from 30 to 99.9% by weight relative to the total weight of the composition;
b) at least one ketone peroxide is preferably selected from the group consisting of methyl-ethyl-ketone peroxide, methyl-isobutyl-ketone peroxide, 2,4-pentanedione peroxide and mixtures thereof, preferably methyl ethyl ketone peroxide and methyl isobutyl ketone peroxide, even more preferably methyl ethyl ketone peroxide;
the ketone peroxide being present in said composition at a concentration ranging from 0.1 to 30% by weight relative to the total weight of the composition;
c) at least hydrogen peroxide which may be present in the composition at a concentration ranging from 0.0005 to 3% by weight relative to the total weight of the composition.

Preferably, the composition according to the present invention comprises:
a) at least one aromatic peroxide selected from the group consisting of t-butyl peroxybenzoate, cumyl peroxyneoheptanoate, cumyl peroxyneodecanoate, 2,5-dimethyl-2,5-(dibenzoylperoxy)hexane, tert-butyl-cumyl peroxide, dicumyl peroxide, cumene hydroperoxide, di(2,4-dichlorobenzoyl) peroxide, 1,3 1,4-bis-(tert-butylperoxyisopropyl)benzene, and mixtures thereof, preferably t -butyl; the aromatic peroxide being present in said composition at a concentration ranging from 30 to 99.9% by weight relative to the total weight of the composition;
b) at least one ketone peroxide is preferably selected from the group consisting of methyl-ethyl-ketone peroxide, methyl-isobutyl-ketone peroxide, 2,4-pentanedione peroxide and mixtures thereof, preferably methyl ethyl ketone peroxide and methyl ethyl ketone peroxide; the ketone peroxide being present in said composition at a concentration ranging from 0.1 to 30% by weight relative to the total weight of the composition;
c) at least hydrogen peroxide which may be present in the composition at a concentration ranging from 0.0005 to 3% by weight relative to the total weight of the composition.

Preferably, the composition according to the present invention comprises:
a) at least one aromatic peroxide selected from the group consisting of t-butyl peroxybenzoate, cumyl peroxyneoheptanoate, cumyl peroxyneodecanoate, 2,5-dimethyl-2,5-(dibenzoylperoxy)hexane, and mixtures thereof, preferably t-butyl peroxybenzoate; the aromatic peroxide being present in said composition at a concentration ranging from 30 to 99.9% by weight relative to the total weight of the composition,
b) at least one ketone peroxide is preferably selected from the group consisting of methyl-ethyl-ketone peroxide, methyl-isobutyl-ketone peroxide, 2,4-pentanedione peroxide and mixtures thereof, preferably methyl ethyl ketone peroxide and methyl ethyl ketone peroxide, more preferably methyl ethyl ketone peroxide; the ketone peroxide being present in said composition at a concentration ranging from 0.1 to 30% by weight relative to the total weight of the composition;
c) at least hydrogen peroxide which may be present in the composition at a concentration ranging from 0.0005 to 3% by weight relative to the total weight of the composition.

Solvent

The composition may also comprise at least one solvent. The solvent according to the invention can be of any type known to those skilled in the art, suitable for solvating organic peroxides, especially aromatic peroxides and ketone peroxide.

In particular, the presence of a solvent can help promote the homogeneity of the composition of the present invention.

Preferably, the solvent according to the invention is an organic solvent selected from the group consisting of a ketone solvent, an aryl solvent, an ether solvent, an alcohol solvent, a mineral oil and a hydrocarbon solvent.

More preferably, the solvent is selected from the group consisting of dimethyl phthalate, dimethyl terephthalate, methyl isobutyl ketone, cyclohexanone, ethyl acetate, isododecane, glycol ether, ethylene glycol, isopropanol or a combination thereof. . More preferably the solvent is isopropanol.

Within the meaning of the present invention, it is to be understood that glycol ether is different from an additive having an ether group as defined below.

Additives

The composition of the invention may comprise one or more additives.

Preferably, the additive is a compound having an ether group, preferably is a compound having the following formula (V) or (VI):

[Chem 10]
R ₁ -(OC ₂ H ₄ ) _n -OR ₂
(V)
Where
R ₁ -(O-CH ₂ -CH(CH ₃ )) _n -OR ₂
(VI)
in which :
● n represents an integer ranging from 1 to 8,
● R ₁ and R ₂ represent, independently of each other:
- a hydrogen atom, or
- a C ₁ to C ₈ alkyl radical, linear or branched, substituted or unsubstituted, or
- R ₁ and R ₂ together forming an ether crown, said ether crown preferably having from 4 to 8 ethylene oxide groups, more preferably having from 4 to 5 ethylene oxide groups, and even more preferably having 5 ethylene oxide groups 'ethylene.

Preferably, R ₁ represents a hydrogen group or a methyl group, more preferably a hydrogen group.

Preferably, R ₂ represents a linear or branched, substituted or unsubstituted C ₁ to C ₈ alkyl radical, more preferably represents a linear C ₁ to C ₈ alkyl radical, more preferably a C ₂ alkyl radical.

Preferably, n represents an integer ranging from 1 to 3, more preferably is equal to 2.

Preferably, R ₁ represents a hydrogen group or a methyl group, more preferably a hydrogen group and R ₂ represents a C ₁ to C ₈ alkyl radical of linear or branched alkyl, substituted or not, more preferably represents an alkyl radical in C ₁ to C ₈ linear, more preferably a C ₂ alkyl radical.

Preferably, R ₁ represents a hydrogen group or a methyl group, more preferably a hydrogen group, R ₂ represents a C ₁ to C ₈ alkyl radical of linear or branched alkyl, substituted or not, more preferably represents an alkyl radical in C ₁ to C ₈ linear, more preferably a C ₂ alkyl radical and n represents an integer ranging from 1 to 3, more preferably is equal to 2.

Preferably, the compound having an ether group has the formula (V) as previously defined.

Preferably, the compound having an ether group is selected from the group consisting of di(ethylene glycol) ethyl ether (EDGE), di(ethylene glycol) ethyl methyl ether (DEGMEE), 1, 4,7,10,13-pentaoxycyclopentadecane, di(propylene glycol) ethyl ether, di(propylene glycol) ethyl methyl ether and a mixture thereof, more preferably is selected from the group consisting of a di(ethylene glycol) ethyl ether, a di(ethylene glycol) ethyl methyl ether and a mixture thereof, and even more preferably is a di(ethylene glycol) ethyl ether .

Preferably, the compound having an ether group is present at a concentration ranging from 0.1% to 20% by weight relative to the total weight of the composition.

Preferably, the composition according to the present invention exhibits an APHA color value of less than or equal to 200, preferably 150, more preferably 100 over a period of time of at least 5 days, in particular of at least 15 days , especially at least 20 days, preferably at least 30 days, more preferably at least 50 days and even more particularly longer than at least 90 days, especially at room temperature, preferably in the dark.

Preparation of composition

The present invention also relates to a process for the preparation of the aforementioned composition comprising the mixture of at least one aromatic peroxide, as defined above, and at least one ketone peroxide as defined above.

Preferably, the at least one aromatic peroxide, as defined above, and the ketone peroxide as defined above can be mixed and agitated by any methods known to those skilled in the art.

The composition obtained has the advantage of being color stable over time.

Use of composition

Another object of the present invention relates to the use of the aforementioned composition in order to prepare a polymer, preferably styrenic polymers, or a polymer resin, in particular a polymer ester resin, said polymer ester resin preferably being chosen from the group consisting of unsaturated polyester resin, acrylic resin, methacrylic resin and vinyl ester resin, more preferably selected from the group consisting of unsaturated polyester resin and vinyl ester resin.

Preferably, the styrenic polymers are selected from the group consisting of polystyrene, high impact polystyrene (HIPS), acrylonitrile-butadiene-styrene copolymers (ABS), acrylonitrile-styrene acrylate copolymers (ASA), styrene-acrylonitrile copolymers (SAN), SAN modified with elastomers, methacrylate-butadiene-styrene (MBS) copolymers, styrene-butadiene copolymers, styrene-butadiene-styrene (SBS) block copolymers and their partially or fully hydrogenated derivatives, styrene-isoprene copolymers, styrene-isoprene-styrene block copolymers ( SIS) and their partially or completely hydrogenated derivatives, and styrene-(meth)acrylate copolymers such as styrene-methyl methacrylate (S/MMA) copolymers.

Preferably, the styrenic polymers are selected from the group consisting of polystyrene, acrylonitrile-butadiene-styrene (ABS) copolymers and styrene-acrylonitrile (SAN) copolymers.

As provided herein, the term "polymer resin" refers to a polymer whether or not in combination with a reactive monomer.

As provided herein, the term "polymeric ester resin" refers to a polymer comprising repeating ester units in association or not with a reactive monomer.

Preferably, the polymer resin is selected from the group consisting of polymer ester resin, particularly unsaturated polyester resin, acrylic resin, methacrylic resin and vinyl ester resin. More preferably, the polymeric ester resin is selected from the group consisting of unsaturated polyester resin and vinyl ester resin, and even more preferably, the polymeric resin is an unsaturated polyester resin.

Methods for the synthesis of a polymeric resin are well known to those skilled in the art.

Preferably, the polymer is dissolved in a reactive monomer composition, i.e. a composition which comprises the reactive monomer. Preferably, said reactive monomer according to the invention can react with the polymer according to the invention by a copolymerization reaction.

Preferably, the reactive monomer is selected from the group consisting of a vinyl compound, an acrylic compound and an allyl compound.

By way of example of a vinyl compound which can be used according to the invention, it is possible to cite a styrene compound, such as styrene, methylstyrene, p-chlorostyrene, t-butylstyrene, divinylbenzene or bromostyrene, vinylnaphthalene, divinylnaphthalene, vinyl acetate, vinyl propionate, vinyl pivalate, vinyl ether and divinyl ether.

By way of example of an acrylic compound which can be used according to the invention, mention may be made of methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, isobutyl acrylate , phenyl acrylate, and benzyl acrylate.

By way of example of an allyl compound which can be used according to the invention, mention may be made of allyl phthalate, diallyl phthalate, diallyl isophthalate, triallyl cyanurate and diallyl terephthalate.

Preferably, the polymer of the unsaturated polyester resin according to the invention can be obtained by condensation of one or more acid monomers and/or of one or more acid anhydride monomers with one or more monomers of polyol provided that at least one of the components comprises ethylenic unsaturation. More preferably, the unsaturated polyester resin according to the invention is obtained by condensation of one or more polycarboxylic acid monomers and/or one or more polycarboxylic acid anhydride monomers and one or more polycarboxylic acid monomers. glycol, provided that at least one of the components comprises ethylenic unsaturation.

Preferably, the polymer of the vinyl ester resin according to the invention can be obtained by condensation of one or more polyepoxide resins with one or more monocarboxylic acid monomers having ethylenic unsaturation.

The acid monomer according to the invention can be of any type known to those skilled in the art. However, the acid monomer according to the invention is preferably selected from the group consisting of phthalic acid, maleic acid, oxalic acid, malonic acid, isophthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, succinic acid, sebacic acid, azelaic acid , adipic acid and fumaric acid.

The monocarboxylic acid monomer according to the invention can be of any type known to those skilled in the art. Preferably, the monocarboxylic acid monomer according to the invention is selected from the group consisting of acrylic acid such as methacrylic acid, ethylacrylic acid, propylacrylic acid, isopropylacrylic acid, butylacrylic acid, isobutylacrylic acid, phenylacrylic acid, benzylacrylic acid, halogenated acrylic acid, and cinnamic acid.

The acid anhydride monomer according to the invention can be of any type known to those skilled in the art. Preferably, the acid anhydride monomer according to the invention is selected from the group consisting of phthalic anhydride, maleic anhydride, oxalic anhydride, malonic anhydride, isophthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, succinic anhydride, sebacic anhydride, azelaic anhydride, adipic anhydride and fumaric anhydride.

The polyol according to the invention can be of any type known to a person skilled in the art. Preferably, the polyol according to the invention is a glycol selected from the group consisting of an aliphatic diol and an aromatic diol. More preferably, the polyol according to the invention is selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, pentylene glycol, hexylene glycol and neopentylene glycol.

The polyepoxide resin according to the invention can be of any type known to a person skilled in the art. The polyepoxide resin according to the invention is preferably selected from the group consisting of polyhydric alcohol glycidyl polyethers and polyhydric phenol glycidyl polyethers.

Preferably, the polymer resin, in particular the polymer ester resin, preferably selected from the group consisting of unsaturated polyester resin, acrylic resin, methacrylic resin and vinyl ester resin, according to the invention is a thermosetting resin.

Preferably, the polymer resin, in particular the polymer ester resin, preferably selected from the group consisting of unsaturated polyester resin, acrylic resin, methacrylic resin and vinyl ester resin, according to the invention is a thermosetting resin.

In particular, the invention relates to the use of the composition as defined above as a hardening agent for the preparation of a polymer resin, preferably a polymer ester resin, or as a radical initiator for the polymerization of unsaturated monomers, preferably unsaturated based styrene monomers.

According to the present invention, the term "polymerization" also includes the characteristic "copolymerization".

The polymer resin, in particular the polymer ester resin, preferably chosen from the group consisting of unsaturated polyester resin acrylic resin, methacrylic resin and vinyl ester resin, according to the invention is preferably hardenable by adding the composition according to invention as a curing agent under a temperature allowing the curing reaction.

Using Ketone Peroxide

Another aspect of the present invention relates to the use of at least one ketone peroxide, as defined above, to improve the color stability of at least one aromatic peroxide, as defined above, in particular at a temperature ranging from from 15°C to 30°C, especially from 20°C to 30°C, and preferably in the dark.

Furthermore, the invention relates to the use of at least one ketone peroxide, as defined above, to reduce the APHA value of at least one aromatic peroxide, as defined above, in particular at a temperature ranging from 15 °C to 30°C, especially from 20°C to 30°C.

Polymer resin composition

The present invention also relates to a polymer resin composition comprising:
- at least one composition as defined above,
- at least one polymer resin as previously disclosed, preferably selected from the group consisting of unsaturated polyester resins.

The examples below are given by way of illustration of the present invention.

Examples

Example 1

I. Organic peroxides tested

The organic peroxides used in the experimental protocol described below are listed below:
● Tert-butyl peroxybenzoate sold under the name Luperox® P,
● Methyl-ethyl-ketone peroxide sold under the name Luperox® K2
● Methyl-isobutyl-ketone peroxide sold under the name Luperox® DDM-C

II. Composition tested

In Tables 1 and 2, compositions A and A1 correspond to the virgin product Luperox® P sold by Arkema. Compositions B to F and B1 to G1 were prepared at the same time as the ingredients listed below.

The contents are expressed as percentage by weight relative to the total weight of the composition.

Compositions A and B to F Compositions HAS B VS D E F Luperox® P 100 94 92 90 88 80 Luperox®
K2 - 6 8 10 12 20

Compositions A1 and B1 to G1 Compositions A1 B1 C1 D1 E1 F1 G1 Luperox® P 100 96 94 92 90 88 80 Luperox® DDM-C - 4 6 8 10 12 20

III. Experimental protocol

The color stability of each composition disclosed in Tables 1 and 2, and stored in the dark in a closed tube, was evaluated with the spectral colorimeter sold under the name LICO 620, from the company Hach at a temperature of 40 °C.

APHA color values were determined for each composition over a 90 day time period.

The results for compositions A and B through F were plotted on the and the results for compositions A1 and B1 through G1 were plotted on the .

IV. Results

4.1. Results – Compositions A and B to F

The represents measurements of APHA values as a function of time for compositions A and B to F shown in Table 1 at a temperature of 40°C.

The results show that the APHA values measured at a temperature of 40° C. for compositions B to F are lower than those measured for composition A comprising only tert-butyl peroxybenzoate.

In particular, the detailed results on the demonstrate a peak in the coloration of composition A corresponding to the virgin Luperox® P product over a period of time of less than 25 days compared with compositions B to F.

The results also show that the color increase of compositions B to F comprising a mixture of aromatic peroxide and ketone peroxide at a temperature of 40°C is significantly lower than that of composition A comprising only tert-butyl peroxybenzoate .

Consequently the results prove that the composition according to the present invention has better color stability over time than a composition comprising only the aromatic peroxide.

The results also show that the addition of ketone peroxide causes the APHA values of tert-butyl peroxybenzoate to decrease at a temperature of 40°C.

4.2. Results – Compositions A1 and B1 to G1

The represents measurements of APHA values as a function of time for compositions A1 and B1 to G1 illustrated in Table 2 at a temperature of 40°C.

The results show that compositions B1 to G1 which comprise a mixture of aromatic peroxide and ketone peroxide exhibit better color stability than composition A1 which comprises only tert-butyl peroxybenzoate at a temperature of 40°C.

Indeed, the results demonstrate that the APHA values measured at a temperature of 40° C. concerning compositions B1 to G1 are lower than the APHA values measured for composition A1 comprising only tert-butyl peroxybenzoate.

The results prove that the compositions according to the present invention have better color stability than a composition comprising only the aromatic peroxide over time.

The results also show that the addition of ketone peroxide causes the APHA values of tert-butyl peroxybenzoate to decrease at a temperature of 40°C.

Example 2

In the following example, the color evolution of a Luperox® P product, which had been previously stored in the dark for a period of 21 days, was closely monitored after the addition of ketone peroxide to several weight concentrations at room temperature.

I. Experimental protocol

First of all, a fresh Luperox® P product sold by Arkema was made available to evaluate its color at room temperature with a spectral colorimeter sold under the name LICO 620 by the company Hatch. The color of this product was observed to be 30 APHA.

This product was then stored at 40°C for a period of 90 days in the dark in a closed tube, under standard conditions, i.e. the product was not shaken or moved for this period.

After this period of time, the color of this product was again measured with the aforementioned spectral colorimeter and the development of a yellowish color was observed. Indeed, this color evolution is supported by the fact that the APHA value of Luperox® P is greater than 500.

Subsequently, ketone peroxide was added to the Luperox® P product at several concentrations (2%, 4%, 6%, 8%, 10%, 12% and 20% by weight). In each case, the resulting mixture was then stored for a further 21 days at 25°C.

The resulting compositions have been listed in Table 3 below.

Compositions A2 to H2 Compositions A2 B2 C2 D2 E2 F2 G2 H2 Luperox® P 100 98 96 94 92 90 88 80 Luperox®
K2 - 2 4 6 8 10 12 20

The color evolution of each composition over time has been plotted on the .

II. Results

The represents APHA values as a function of time measured at 40°C.

It can be observed that the addition of ketone peroxide causes the APHA values to decrease over time for tert-butyl peroxybenzoate at room temperature.

This shows that the addition of ketone peroxide effectively decreases the yellowish color of a Luperox® P product which had been previously stored for a period of time of 90 days.

In particular, the coloration of Luperox® P decreases with the absorption of the concentration of ketone peroxide.

Claims (18)

Composition comprising:
a) at least one aromatic peroxide comprising at least one aromatic nucleus and at least one peroxo function -OO- in its structure; the aromatic ring being linked to said peroxo function by a covalent bond or an alkyl group comprising from 1 to 20 carbon atoms;
the aromatic peroxide being present in said composition at a concentration ranging from 30 to 99.9% by weight relative to the total weight of the composition;
b) at least one ketone peroxide being at a concentration ranging from 0.1 to 30% by weight relative to the total weight of the composition. Composition according to Claim 1, characterized in that the said aromatic peroxide comprises at least one benzene nucleus. Composition according to Claim 1 or 2, characterized in that the said aromatic peroxide is chosen from the group consisting of aromatic peresters, aryl-alkyl peroxides, aryl hydroperoxides, aromatic diacyl peroxides and mixtures thereof, preferably aromatic peresters. Composition according to Claim 3, characterized in that the said aromatic peresters are chosen from the group consisting of perbenzoates, aryl peralkylates, aromatic diperesters and mixtures thereof, preferably is a perbenzoate. Composition according to Claim 1, characterized in that the said aromatic peroxide has the following formula (I):
[Chem 1]

in which :
● R ₁ represents:
- a group –C(=O)R' ₁ , in which R' ₁ denotes an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or several halogen atoms, or
- a linear or branched C ₁ to C ₂₀ alkyl radical ending in an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, optionally substituted by a peroxy group, and/or one or more halogen atoms; Where
- a –CR' ₁ group, in which R' ₁ denotes an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms ,
● R ₂ represents:
- a linear or branched C ₁ to C ₂₀ alkyl radical,
- an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms,
- a group -R ₃ OOR ₄ , in which R ₃ represents a linear or branched C ₈ to C ₂₀ alkyl radical, preferably a C ₈ to C ₁₀ alkyl radical, and R ₄ represents a group –C(=O ) R' ₄ in which R' ₄ denotes an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more halogen atoms,
- a linear or branched C ₁ to C ₂₀ alkyl radical ending in an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or more carbon atoms 'halogen,
- a group –C(=O)R' ₂ , in which R' ₂ denotes an aryl group having from 6 to 32 carbon atoms optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical and/or one or several halogen atoms, or
- a hydrogen atom. Composition according to Claim 5, characterized in that, in formula (I):
● R ₁ represents:
- a group –C(=O)R' ₁ , in which R' ₁ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms, or
- a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a branched C ₁ to C ₁₀ alkyl radical, which terminates in a benzene ring which is optionally substituted by a linear C ₁ to C ₁₀ alkyl radical or branched, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms,
● R ₂ represents:
- a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₅ alkyl radical, more preferably a branched C ₁ to C ₅ alkyl radical,
- a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a linear or branched C ₁ to C ₄ alkyl radical and/or one or more halogen atoms, preferably chlorine atoms ,
- a group -R ₃ OOR ₄ , in which R ₃ represents a linear or branched C ₈ to C ₂₀ alkyl radical, preferably a C ₈ to C ₁₀ alkyl radical, and R ₄ represents a group –C(=O )R' ₄ in which R' ₄ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms ,
- a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a branched C ₁ to C ₁₀ alkyl radical, which ends in a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, especially a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms,
- a group –C(=O)R' ₂ , in which R' ₂ denotes a benzene ring optionally substituted by a linear or branched C ₁ to C ₁₀ alkyl radical, preferably a C ₁ to C ₄ alkyl radical, and/or one or more halogen atoms, preferably chlorine atoms,
- a hydrogen atom. Composition according to any one of the preceding claims, characterized in that the aromatic peroxide is selected from the group consisting of t-butyl peroxybenzoate, cumyl peroxyneoheptanoate, cumyl peroxyneodecanoate, 2,5-dimethyl-2,5-(dibenzoylperoxy )hexane tert-butyl-cumyl peroxide, dicumyl peroxide, cumene hydroperoxide, di(2,4-dichloro benzoyl) 1,3 1,4-bis-(tert-butylperoxyisopropyl)benzene peroxide, and mixtures thereof these, preferably t-butyl peroxybenzoate, cumyl peroxyneoheptanoate, cumyl peroxyneodecanoate, 2,5-dimethyl-2,5-(dibenzoylperoxy)hexane and a mixture thereof. Composition according to any one of the preceding claims, characterized in that the ketone peroxide is chosen from the group consisting of methyl-ethyl-ketone peroxide, methyl-isobutyl-ketone peroxide, 2,4-pentanedione peroxide and mixtures thereof, even more preferably is selected from the group consisting of methyl-ethyl-ketone peroxide and methyl-isobutyl-ketone peroxide. Composition according to any one of the preceding claims, characterized in that the aromatic peroxide is t-butyl peroxybenzoate and in that the ketone peroxide is chosen from the group consisting of methyl-ethyl-ketone peroxide and methyl peroxide -isobutyl-ketone. Composition according to any one of the preceding claims, characterized in that it additionally comprises hydrogen peroxide. Composition according to any one of the preceding claims, further comprising at least one compound having an ether group, preferably having the following formula (V) or (VI):
[Chem 2]

In which :
● n represents an integer ranging from 1 to 8,
● R ₁ and R ₂ represent, independently of each other:
- a hydrogen atom, or
- a C ₁ to C ₈ alkyl radical, linear or branched, substituted or unsubstituted, or
- R ₁ and R ₂ together forming an ether crown, said ether crown preferably having from 4 to 8 ethylene oxide groups, more preferably having from 4 to 5 ethylene oxide groups, and even more preferably having 5 ethylene oxide groups 'ethylene. Composition according to any one of the preceding claims, comprising at least one solvent, preferably an organic solvent selected from the group consisting of a ketone solvent, an aryl solvent, an ether solvent, an alcohol solvent, a mineral oil and a hydrocarbon solvent. , and more preferably selected from the group consisting of a ketone solvent and an alcohol solvent. Process for the preparation of the composition as defined according to any one of the preceding claims, comprising mixing at least one aromatic peroxide, as defined according to any one of Claims 1 to 7, and at least one ketone peroxide as defined in claim 1 or 8. Use of the composition as defined according to any one of Claims 1 to 12 in order to prepare a polymer, preferably styrenic polymers, or a polymer resin, in particular a polymer ester resin, the said polymer ester resin preferably being chosen from the group consisting of unsaturated polyester resin, acrylic resin, methacrylic resin and vinyl ester resin, more preferably selected from the group consisting of unsaturated polyester resin and vinyl ester resin. Use according to claim 14 of the composition as defined according to any one of claims 1 to 12 as a hardening agent for the preparation of a polymer resin, preferably a polymer ester resin. Use according to Claim 14 of the composition as defined according to any one of Claims 1 to 11 as a radical initiator for the polymerization of unsaturated monomers, preferably styrenic monomers with an unsaturated base. Use of at least one ketone peroxide as defined according to claim 1 or 8 in order to improve the color stability or to decrease the APHA value of at least one aromatic peroxide, as defined according to any one of the claims 1 to 7. Polymer resin composition comprising:
- at least one composition as defined in any one of claims 1 to 12,
- at least one polymer resin as defined in claim 14, preferably selected from the group consisting of unsaturated polyester resins.