KR100277053B1 - Impact additive of the core/shell type for thermoplastic polymers - Google Patents

Abstract

The present invention relates to a core / shell type impact resistance additive for thermoplastic polymers.

Impact resistance additives include a crosslinked elastic core based on n-alkyl acrylate and a shell made of poly (alkyl methacrylate) grafted on the core.

Description

Core / Shell Type Impact Resistance Additives for Thermoplastic Polymers {IMPACT ADDITIVE OF THE CORE / SHELL TYPE FOR THERMOPLASTIC POLYMERS}

The present invention provides not only core / shell type impact additives but also copolymers mainly containing thermoplastic polymers, in particular vinyl chloride homopolymers or vinyl chlorides, core / shell type impact additives and any other additives. It relates to a composition to contain.

Some synthetic resins, particularly those based on poly (vinyl chloride) or copolymers mainly containing vinyl chloride, are widely used in the construction field because of their low cost, good physical and / or chemical properties.

Nevertheless, they show low impact strength at ambient or low temperature, or even after aging also have low impact strength.

A method for overcoming this defect is proposed by incorporating materials known as impact resistance additives, which are general polymers showing elasticity, into these thermoplastic resins.

US Patent No. 3,678,133 discloses a core / shell type impact resistance additive consisting of an elastic core and a more rigid thermoplastic shell.

In this patent, the elastic core is obtained by polymerizing a mixture of monomers containing at least 50% by weight of an alkyl acrylate having an alkyl group having 2 to 8 carbon atoms and a small amount of crosslinking agent. The alkyl acrylate is preferably n-butyl acrylate.

It is also mentioned that alkyl acrylates with long chains have the disadvantage that the polymerization process is very difficult. As an example, 2-ethylhexyl acrylate is illustrated.

In addition, a rigid thermoplastic shell is obtained by polymerizing a mixture of monomers containing 40 to 100% by weight of alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms.

The impact resistance additives of this patent are prepared in such a way that the polymerization of the rigid thermoplastic shell takes place on the surface of the elastic phase, preferably as a separate layer which covers the elastic core somewhat completely.

Although the impact resistance additives thus obtained significantly improve the impact resistance at ambient temperatures of the resins containing them, it has been found that there is a reduction in the mechanical properties of the resins, in particular the impact resistance at low temperatures.

A core / shell type impact resistance additive comprising a core based on alkyl acrylate or polyorganosiloxane rubber and a shell based on poly (alkyl methacrylate) or styrene-acrylonitrile copolymer, comprising the following components: Core / shell type impact resistance additives are now found:

a) 70 to 90% by weight, preferably 75 to 85% by weight, of a crosslinked elastic core composed of the following components:

1) a mixture of n-alkyl acrylates having alkyl groups of 5 to 12 carbon atoms, preferably 5 to 8 carbon atoms or alkyl acrylates having straight or branched chain alkyl groups of 2 to 12 carbon atoms, preferably 4 to 8 carbon atoms Copolymers (I) or polyorganosiloxane rubbers, polyfunctional crosslinkers containing unsaturated groups in the molecule and at least one of which is CH ₂ = C <vinyl, and optionally containing unsaturated groups in the molecule and at least one of CH ₂ = CH 20 wt% to 100 wt%, preferably 20 wt% to 90 wt%, of the nucleus composed of a multi-functional graft agent of -CH ₂ -allyl type, provided that the nucleus is from 0.05 mol% to a crosslinking agent and a graft agent that may be contained. 5 mol%, preferably in an amount of 0.5 mol% to 1.5 mol%);

2) a copolymer (II) of n-alkyl acrylate having an alkyl group having 4 to 12 carbon atoms, preferably 4 to 8 carbon atoms or a mixture of alkyl acrylates defined in 1) above, and containing an unsaturated group in the molecule; 80% by weight to 0% by weight, preferably 80% by weight to 10% by weight, of at least one of which is composed of a multifunctional graft agent of at least one of CH ₂ = CH-CH ₂ -allyl, provided that the shell is 0.05 mole of the graft agent. % To 2.5 mol%, preferably 0.5 mol% to 1.5 mol%);

b) polymers of alkyl methacrylates having alkyl groups of 1 to 4 carbon atoms, or optionally alkyl methacrylates having alkyl groups of 1 to 4 carbon atoms and alkyl acrylates having alkyl groups of 1 to 8 carbon atoms Consisting of random copolymers of (in this case containing alkyl acrylate in an amount of from 5 mol% to 40 mol%, preferably from 10 mol% to 20 mol%), or optionally of styrene-acrylonitrile copolymers 30% to 10% by weight, preferably 25% to 15% by weight, of the shell grafted onto the core.

Examples of n-alkyl acrylates which can be used according to the invention to form copolymer (I) will mention n-pentyl acrylate, n-hexyl acrylate, n-heptyl acrylate, in particular n-octyl acrylate Can be.

Examples of n-alkyl acrylates which can be used according to the invention to form copolymer (II) are n-butyl acrylate, n-pentyl acrylate, n-hexyl acrylate, n-heptyl acrylate, in particular n- Octyl acrylate may be mentioned.

The n-alkyl acrylates that can be used to form the copolymers (I) and / or (II) can be the same or different.

Examples of straight or branched chain alkyl acrylates which may be used according to the invention which form a mixture of the alkyl acrylates constituting the copolymers (I) and / or (II) are ethyl acrylate, n-propyl acrylate, n -Butyl acrylate, amyl acrylate, 2-methylbutyl acrylate, 2-ethylhexyl acrylate, n-hexyl acrylate, n-octyl acrylate, n-decyl acrylate, n-dodecyl acrylate or 3, Mention may be made of 5,5-trimethylhexyl acrylate.

When using a mixture of alkyl acrylates to prepare copolymers (I) and / or (II), n-alkyl acrylics in an amount of at least 10% by weight, preferably 20 to 80% by weight, of the mixture of alkyl acrylates Rate can be used.

As mentioned above, mixtures of the same or different alkyl acrylates can be used to prepare copolymers (I) and / or (II).

According to the invention, preference is given to using n-alkyl acrylates, in particular n-octyl acrylate, for the preparation of copolymers (I) and (II).

If a mixture of alkyl acrylates is used to prepare copolymers (I) and / or (II), 20 to 80% by weight of n-octyl acrylate, preferably 80 to 20% by weight of n-butyl acrylate can be used. Can be.

Examples of alkyl methacrylates that can be used to prepare shells grafted onto crosslinked elastic cores according to the present invention include ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n- Mention may be made of butyl methacrylate, isobutyl methacrylate, in particular methyl methacrylate.

According to the invention, the crosslinking agent used to prepare copolymer (I) is in particular a derivative containing at least two vinyl-type double bonds or optionally one or several vinyl-type double bonds and one It can be selected from derivatives containing allyl double bonds described above. It is preferable to use a compound containing a plurality of vinyl double bonds in a molecule.

Examples of such crosslinkers include divinylbenzene, polyalcohol (meth) acrylates such as trimethylolpropane triacrylate or trimethacrylate, allyl acrylate or methacrylate, alkylene chains having from 2 to 10 carbon atoms. Alkylene glycol diacrylate or dimethacrylate, in particular ethylene glycol diacrylate or dimethacrylate, 1,4-butanediol diacrylate or dimethacrylate or 1,6-hexanediol diacrylate or di Methacrylate, or polyoxyalkylene glycol diacrylate or dimethacrylate of formula (I):

(Wherein X is a hydrogen atom or a methyl radical, n is an integer from 2 to 4, p is an integer from 2 to 20), in particular a molecular weight of the polyoxyethylene radical is approximately 400 (n = 2 in the formula And p = 9), polyoxyethylene glycol diacrylate or dimethacrylate.

According to the invention, the graft agent used to prepare copolymer (II) is in particular a derivative containing at least two allyl double bonds or optionally one or several allyl double bonds and one It can be selected from derivatives containing the above double vinyl type double bond.

It is preferable to use a compound having a large number of allyl double bonds in the molecule.

Examples of such graft agents include diallyl maleate, diallyl itaconate, allyl methacrylate or acrylate, triallyl cyanurate, triallyl isocyanurate, diallyl terephthalate or triallyl trimesate can do.

According to another aspect of the invention, the nucleus of the crosslinked elastic core may consist predominantly of polyorganosiloxanes obtained by emulsion polymerization of the organosiloxane in the presence of a crosslinking agent, optionally a graft agent.

Examples of organosiloxanes include cyclic siloxanes composed of rings having multiple Si-C ring moieties of 3 to 6, such as hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, dodecamethylcyclohexasiloxane or octaphenylcyclotetrasiloxane May be mentioned.

As crosslinking agents that can be used, mention may be made of crosslinking agents of the trifunctional or tetrafunctional silane type, such as trimethoxysilane or tetraethoxysilane.

As the graft agent, it is preferable to use methacryloyloxysiloxane of the following general formula (2):

(Wherein R ¹ is a methyl, ethyl, propyl or phenyl group, R ² is a hydrogen atom or a methyl group, n is 0, 1 or 2 and p is a number from 1 to 6).

As examples of methacryloyloxysiloxanes, mention may be made of the following:

β-methacryloyloxyethyldimethoxymethylsilane,

γ- methacryloyloxypropylmethoxydimethylsilane,

γ- methacryloyloxypropyldimethoxysilane,

γ- methacryloyloxypropyltrimethoxysilane,

γ- methacryloyloxypropylethoxydiethylsilane,

γ-methacryloyloxypropyldiethoxymethylsilane, and

delta-methacryloyloxybutyldiethoxymethylsilane.

Polyorganosiloxane rubbers can be produced, for example, by the method described in EP 0,326,038. In particular, the method described in Reference Example 1 of the above patent can be used, and polyoctamethylcyclotetrasiloxane rubber latex can be obtained by this method.

According to this other form, the crosslinked elastic core may contain up to 40% by weight of a nucleus made of polyorganosiloxane rubber as described above.

The invention also relates to a composition containing the thermoplastic polymer and impact resistance additives as described above.

Thermoplastic polymers can be used in the form of polycondensates, in particular polyamides, polyetheresteramides (PEBAX), polyesters such as polybutylene terephthalate, polycarbonates or alloys of the aforementioned polymers such as XENOY and It may be composed of alloys of the same polycarbonate and polyester. In addition, thermoplastic polymers are the result of copolymerization of poly (alkyl methacrylate), in particular poly (methyl methacrylate), or vinyl chloride homopolymer that can be overchlorinated and one or several ethylenically unsaturated comonomers with vinyl chloride. It may consist of one or several polymers selected from the group consisting of copolymers containing at least 80% by weight of polymerized vinyl chloride. Examples of suitable monomers for the preparation of such copolymers are, in particular, vinylidene halides such as vinylidene chloride or fluoride, vinyl carboxylates such as vinyl acetate, vinyl propionate or vinyl butyrate, acrylic acid and methacrylic Acids and nitriles, amides and alkyl esters derived therefrom, in particular acrylonitrile, acrylamide, methacrylamide; Methyl methacrylate, methyl acrylate, butyl acrylate, ethyl acrylate or 2-ethylhexyl acrylate, vinylaromatic derivatives such as styrene or vinylnaphthalene or olefins such as bicyclo [2.2.1] hept-2-ene , Bicyclo [2.2.1] hepta-2,5-diene, ethylene, propene or 1-butene.

The thermoplastic polymer may also be composed of homopolymers of vinylidene halides such as 1,1-dichloroethylene or 1,1-difluoroethylene.

The thermoplastic polymer is preferably vinyl chloride homopolymer or poly (butylene terephthalate).

The preferred amount of the impact resistance additive blended into the thermoplastic polymer is 1 to 30 parts by weight, preferably 5 to 10 parts by weight, per 100 parts by weight of the thermoplastic polymer used.

In order to define the molecular weight of the impact resistance additive, it is possible to define the viscosity in the molten state which is changed in the same meaning. The viscosity in the molten state may have a wide range when the impact resistant additive is well dispersed during the operation in which the resin composition containing the additive is used. As a representative value of this viscosity in the molten state, the resistance torque value of a brabender ammeter containing 50 g of impact additive is operated at a temperature of 200 ° C. at a rotational speed of an axis of 40 revolutions per minute. As can be seen, the torque at this time is determined after sustaining at 200 ° C. for 20 minutes. Suitable viscosity values in the molten state for impact resistance additives are between 600 and 4000 m.g. Corresponds to the torque value of. In the case of resin compositions wherein the thermoplastic polymer is a polymer containing at least 80% by weight polymerized vinyl chloride, the preferred viscosity value in the molten state for the impact resistance additive is 800 to 3000 m.g., in particular 1000 to 2500 m.g. Corresponds to the torque value of.

Another object of the present invention is a method of preparing the impact resistance additive.

One method produces a crosslinked core consisting of a nucleus and an outer shell in a first step, and in a second step grafts a poly (alkyl methacrylate) shell on the crosslinked core obtained in the first step. It consists of.

According to a preferred method, a crosslinked core consisting of the nucleus and the shell is prepared and the graft operation is carried out using emulsion polymerization techniques. In this case, the following method can be used.

In a first step, 1 to 10 parts by weight of water, 0.001 to 0.03 parts by weight of an emulsifier, a major proportion of n-alkyl acrylate or a mixture of alkyl acrylates as defined above to form the core is polymerized to form the core. And emulsions containing at least one multifunctional crosslinking agent. The reaction mixture thus prepared is stirred and maintained at a temperature near 55 ° C. to 65 ° C., preferably around 60 ° C. Then, 0.001 to 0.5 parts of catalyst which generates free radicals is added and the reaction mixture thus formed is maintained at an ambient temperature of from 100 ° C., for example while stirring for a sufficient time for the monomers to convert substantially completely. Subsequently, a small amount of n-alkyl acrylate or a mixture of alkyl acrylate and graft agent as well as 0.001 to 0.005 parts of catalyst which simultaneously produce free radicals are added simultaneously to the obtained phase.

The second operation of the first step, including the manufacture of the shell, is generally carried out at a higher temperature than that used for the manufacture of the nucleus. This temperature is 100 degrees C or less, Preferably it is 60 degreeC-90 degreeC.

Another form of the first step involves preparing a crosslinked core in a single step by concurrently administering a crosslinking agent and a graft agent (or a compound having both crosslinking and graft action) to the reaction mixture.

In a second step, the core is grafted with alkyl methacrylate. To this end, an appropriate amount of the methacrylate is added to the reaction mixture obtained in the first step to produce a graft copolymer comprising the desired amount of graft chain, if appropriate, an additional amount of emulsifier, and a radical catalyst within the defined range. The resulting and so formed mixture is maintained at a temperature within this range with stirring until the grafting monomer is substantially completely converted.

As the emulsifier, any surfactant known can be used, whether anionic, nonionic or cationic. In particular emulsifiers are sodium or potassium salts of fatty acids, in particular sodium laurate, sodium stearate, sodium palmitate, sodium oleate, mixed sulfates of sodium or potassium and fatty alcohols, in particular sodium lauryl sulfate, sulfosuccinate esters Or potassium salts, sodium or potassium salts of alkylarylsulfonic acids, especially sodium dodecylbenzenesulfonate, and sodium or potassium salts of fatty monoglyceride monosulfonic acid salts, or, optionally, reaction products of ethylene oxide and alkylphenols or aliphatic alcohols and alkylphenols. The same nonionic surfactant can be chosen. It is also possible to use mixtures of these surfactants if necessary.

Catalysts usable in both the first emulsion polymerization step and the second emulsion polymerization step are compounds which generate free radicals under temperature conditions selected for polymerization. This compound is especially hydrogen peroxide; Alkali metal persulfonates, especially sodium or potassium persulfate; Ammonium persulfate; Percarbonate; Peracetate, perborate; Peroxides such as benzoyl peroxide or lauroyl peroxide, or peroxide compounds such as cumene hydroperoxide, diisopropylbenzene hydroperoxide, para-mentane hydroperoxide or t-butyl hydroperoxide.

However, by way of example, redox rings formed by mixing peroxide compounds as defined above, in particular by reducing agents such as alkali metal sulfinates, alkali metal bisulfinates, sodium formaldehyde sulfoxylate (NaHSO ₂ · HCH0), ascorbic acid, glucose Preference is given to using circular catalyst systems and in particular those catalyst systems which are water soluble, such as, for example, potassium persulfate / sodium metabisulfite, optionally diisopropylbenzene hydroperoxide / sodium formaldehyde sulfoxylate.

Also, in one and / or other stages of the polymerization mixture, chain-limiting compounds, in particular t-dodecyl mercaptan, isobutyl mercaptan, n-octyl, in order to control the molecular weight of the chain grafted to the core and / or nucleus Mercaptans such as mercaptans, n-dodecyl mercaptans or isooctyl mercaptopropionate may be added, or optionally compounds such as phosphates may be added to control the ionic strength of the polymerization mixture.

The reaction mixture, which is obtained as a result of the second emulsion polymerization step and which contains an aqueous suspension of the additive according to the invention, is then treated to separate the additive therefrom. To this end, for example, according to the surfactant used, the emulsion is contacted with a salt solution (CaCl ₂ or AlCl ₃ ) or a solution acidified with concentrated sulfuric acid, followed by flocculation, and then the flocculated solid product is separated by filtration and washed. Dry to obtain graft copolymer as a powder. Spray-drying techniques may also be used to recover the additives contained in the emulsion.

The additives obtained are in the form of powders whose particle sizes can range from several microns to 200-300 microns, for example 0.05-5, depending on the technique used to separate the graft copolymer from the emulsion polymerization mixture. do.

The composition according to the invention can be prepared by any method capable of producing a homogeneous mixture containing the thermoplastic polymer, the impact resistance additive according to the invention and optionally other additives. For example, after drying-mixing the components constituting the resin composition, the resulting mixture is extruded and the extrudate is reduced to pellets. When the thermoplastic polymer is obtained by emulsion polymerization, the solid product contained therein, as described above with respect to the additive separation by mixing with the emulsion containing the additive according to the present invention and the emulsion of the thermoplastic polymer and treating the obtained emulsion therein It is convenient to separate.

Additives other than impact resistance additives optionally present in the resin composition according to the invention are in particular such as paints, dyes, plasticizers, antioxidants, heat stabilizers, processing aids or lubricants.

The PVC composition obtained according to the present invention shows good impact strength at ambient temperatures as well as low temperatures such as -30 ° C or even -40 ° C.

The composition of the present invention can be usefully used for producing fragments or exterior materials, especially for use in the building industry, or for producing pipes for conveying water.

The following examples are intended to illustrate the present invention.

Example 1 (according to the present invention)

The manufacture is carried out in a 2-liter reactor equipped with a stirrer and a temperature recorder and equipped with a jacket through which the heat transfer fluid passes to maintain the temperature of the reactor.

1) Preparation of Crosslinked Elastic Core of Impact Resistant Additives:

After 800 g of deionized water and 2.46 g of disodium phosphate are degassed with nitrogen, they are introduced into the reactor above, kept at room temperature with stirring, and 20.58 g of sodium lauryl sulfate are dissolved in these mixtures as emulsifiers. .

The temperature of the reactor contents is then brought to 57 ° C., then 423 g of n-octyl acrylate and 5.08 g of 1,4-butanediol diacrylate are added to the contents simultaneously while maintaining this temperature.

After bringing the temperature of the reactor to 63 ° C., 0.41 g of sodium metabisulfite in 5.59 ml of water and 0.62 g of potassium persulfate in 6.58 ml of water are added to the reaction mixture as a catalyst system. The reaction is then continued for 2 hours, after which the temperature of the reactor is brought to 80 ° C., and then 47 g of n-octyl acrylate, 2.36 g of diallyl maleate and 0.8 g of potassium persulfate are added simultaneously.

The temperature of the reactor is maintained at 80 ° C. for 1 hour. A crosslinked elastic core consisting of the following components is obtained with a conversion of 98%:

1) 89.66% by weight of nuclei consisting of n-octyl acrylate / 1,4-butanediol diacrylate copolymer (I) and

2) 10.34% by weight of the sheath consisting of n-octyl acrylate / diallyl maleate copolymer (II).

This core contains 1 mol% 1,4-butanediol diacrylate and 0.47 mol% diallyl maleate.

2) Grafting of Methyl Methacrylate on Crosslinked Elastic Cores

118 g of methyl methacrylate is added to the reaction mixture obtained above while maintaining the temperature at 80 ° C. for 1 hour with continuous stirring. In addition, 1.7 g of diisopropylbenzene hydroperoxide in 78 ml of water and 0.2 g of sodium formaldehyde sulfoxylate in 4 ml of water are added simultaneously.

The contents of the reactor are maintained at 80 ° C. for 1.5 hours after the start of the introduction of methyl methacrylate and 0.31 g of t-butyl hydroperoxide and 0.8 g of sodium metabisulpit in 15 ml of water are added to the contents. . The reaction mixture is then maintained at 80 ° C. for 1 hour. At the end of this time, the contents of the reactor are cooled to ambient temperature and the resulting graft copolymer latex with an average particle diameter of 0.08 μm is aggregated in a salt solution acidified with concentrated sulfuric acid. The agglomerated product is then filtered, washed and dried to obtain a powder comprising the impact resistance additive.

The conversion of methyl methacrylate is 99% during grafting. The impact resistance additive contains a portion of the grafted poly (methyl methacrylate) chain representing 19.82% by weight of the additive and operates at 1400 m.g. of brabender ammeter torque operating under the above conditions. It has a viscosity in the molten state corresponding to

Example 2 (according to the present invention)

1) Preparation of Crosslinked Elastic Core of Impact Resistant Additives

After degassing 2000 g deionized water and 5.85 g disodium phosphate with nitrogen, 5 liters installed as in Example 1 were introduced into the reactor, kept at room temperature with stirring, and then 245 g of sodium lauryl sulfate was added. It is dissolved in this mixture as an emulsifier.

The temperature of the reactor contents was then set at 57 ° C., while maintaining this temperature, 904.5 g of n-octyl acrylate, 301.5 g of n-butyl acrylate and 14.4 g of 1,4-butanediol diacrylate were simultaneously Add to the contents.

The temperature of the reactor is brought to 63 ° C., then 22.6 g sodium bisulfite in 10 ml of water and 1.60 g potassium persulfate in 33.83 ml of water are added to the reaction mixture as a catalyst system. The reaction was then continued under adiabatic conditions for 2 hours, after which the temperature of the reactor was brought to 80 ° C., followed by 100.5 g of n-octyl acrylate, 33.5 g of n-butyl acrylate, 6.71 g of 3.73 ml of water. Diallyl maleate and 0.17 g of potassium persulfate are added simultaneously.

The temperature of the reactor is maintained at 80 ° C. for 1 hour.

A crosslinked elastic core composed of the following components is obtained with a conversion of 95.72%:

1) 89.66% by weight of nuclei consisting of n-octyl acrylate / n-butyl acrylate / 1,4-butanediol diacrylate copolymer (I) and

2) 10.34% by weight of the sheath consisting of n-octyl acrylate / n-butyl acrylate / dialkyl maleate copolymer (II).

2) Grafting of Methyl Methacrylate on Crosslinked Elastic Cores

335.3 g of methyl methacrylate are added to the reaction mixture obtained above, while maintaining the temperature at 80 ° C. for 1 hour with continuous stirring. In addition, 4.3 g of diisopropylbenzene hydroperoxide in 195.7 ml of water and 0.40 g of sodium formaldehyde sulfoxylate in 9.28 ml of water are added simultaneously.

The contents of the reactor are maintained at 80 ° C. for 1.5 hours after the start of the introduction of methyl methacrylate and 0.24 g of t-butyl hydroperoxide and 4.6 g of sodium bisulfite in 17 ml of water are added to the contents. The reaction mixture is then maintained at 80 ° C. for 1 hour. At the end of this time, the contents of the reactor are cooled to ambient temperature and the resulting graft copolymer latex is aggregated in a salt solution acidified with concentrated sulfuric acid. The agglomerated product is then filtered, washed and dried to obtain a powder comprising the impact resistance additive.

The conversion of methyl methacrylate during grafting is 98.27%. The impact resistance additive contains a portion of the grafted poly (methyl methacrylate) chain representing 19.77% by weight of the additive and has a viscosity in the molten state corresponding to 1500 mg of Brabender ammeter torque operating under the above conditions. .

In Examples 3 to 7, the same operation as in Example 1 was carried out for the shell grafted on the core using the same reactant (grafting agent and crosslinking agent, catalyst, emulsifier, etc.) in the same weight for the crosslinked elastic core. The preparation is carried out according to the conditions, in which for the preparation of the crosslinked elastic cores, the copolymers (I) and (II) are prepared using the same weight of alkyl acrylates other than n-octyl acrylate.

In Example 3, n-heptyl acrylate is used.

In Example 4, n-hexyl acrylate is used.

In Example 5, n-pentyl acrylate is used.

In Example 6 (not according to the invention), n-butyl acrylate is used.

In Example 7 (not according to the invention), 2-ethylhexyl acrylate is used.

To obtain an impact resistance additive containing a crosslinked elastic core as in Example 1 obtained in a yield of at least 98%, consisting of the following components,

1) about 90% by weight of the nucleus consisting of alkyl acrylate / 1,4-butanediol diacrylate copolymer (I) and

2) about 10% by weight of the sheath consisting of the same alkyl acrylate copolymer (II) / dialkyl maleate as used in 1;

The shell grafted on the core is made of poly (methyl methacrylate) and exhibits about 20% by weight of impact resistance additives.

Example 8 (according to the present invention)

1) Preparation of Crosslinked Elastic Core of Impact Resistant Additives

After degassing with 750 g of deionized water, 2.46 g of disodium phosphate and 0.41 g of sodium metabisulfite in 7.59 ml of water into nitrogen, it is introduced into the reactor of Example 1 and maintained at room temperature with stirring, followed by 100 g of sodium lauryl sulfate are dissolved in these mixtures as an emulsifier.

The temperature of the reactor contents is then brought to 57 ° C. and then 117.5 g of n-octyl acrylate and 1.21 g of allyl methacrylate are added to the contents simultaneously while maintaining this temperature.

The temperature of the reactor is brought to 63 ° C., and then 0.13 g of potassium persulfate in 2.67 ml of water is added to the reaction mixture. The reaction is then continued for 45 minutes, the temperature of the reactor is brought to 80 ° C., and then 353 g of n-butyl acrylate, 5.21 g of allyl methacrylate and 0.5 g of potassium persulfate are added simultaneously in 10.7 ml of water. do.

The temperature of the reactor is maintained at 80 ° C. for 1 hour. A crosslinked elastic core consisting of the following components is obtained with a conversion of 99.9%:

1) 24.89% by weight of nuclei consisting of n-octyl acrylate / allyl methacrylate copolymer (I) and

2) 75.11 weight% of the sheath consisting of n-butyl acrylate / allyl methacrylate copolymer (II).

2) Grafting of Methyl Methacrylate on Crosslinked Elastic Cores

118 g of methyl methacrylate is added to the reaction mixture obtained above while maintaining the temperature at 80 ° C. for 1 hour with continuous stirring. In addition, 1.7 g of diisopropylbenzene hydroperoxide in 78 ml of water and 0.42 g of sodium formaldehyde sulfoxylate in 9.58 ml of water are added simultaneously.

After starting to introduce methyl methacrylate, the contents of the reactor were kept at 80 ° C. for 1.5 hours and 0.33 g of t-butyl hydroperoxide and 0.08 g of sodium metabisulpit in 10 ml of water were added to the contents do. The reaction mixture is then maintained at 80 ° C. for 1 hour. At the end of this time, the contents of the reactor are cooled to ambient temperature and the resulting graft copolymer latex is aggregated in a salt solution acidified with concentrated sulfuric acid. The agglomerated product is then filtered, washed and dried to obtain a powder comprising the impact resistance additive.

The conversion of methyl methacrylate during grafting is quantitative. The impact resistance additive contains 1760 m.g. of brabender ammeter torque containing part of a poly (methyl methacrylate) graft chain representing 19.83% by weight of the additive and operating under the above conditions. It has a viscosity in the molten state corresponding to

Example 9 (according to the present invention)

The production is carried out in a 2-liter reactor equipped with a stirrer and a temperature recorder and equipped with a jacket through which the heat transfer fluid passes to maintain the temperature of the reactor.

1) Preparation of Crosslinked Elastic Core of Impact Resistant Additives

After degassing with 787.5 g of deionized water, 2.58 g of disodium phosphate and 0.42 g of sodium metabisulfite in 7.98 ml of water, introduce into the reactor above, hold at ambient temperature with stirring, and then 105 g Sodium lauryl sulfate is dissolved in these mixtures as an emulsifier.

The temperature of the reactor contents is then brought to 57 ° C., then 493.50 g of n-octyl acrylate and 3.38 g of allyl methacrylate are added to the contents simultaneously while maintaining this temperature.

The temperature of the reactor is brought to 63 ° C., and then 0.66 g potassium persulfate in 14 ml of water is added to the reaction mixture. The reaction is then continued for 2 hours and then the temperature of the reactor is brought to 80 ° C.

The temperature of the reactor is maintained at 80 ° C. for 1 hour. A crosslinked elastic core constituting the n-octyl acrylate / allyl methacrylate copolymer (I) with a conversion of 98.95% is obtained.

This core contains 1 mol% of allyl methacrylate.

2) Grafting of Methyl Methacrylate on Crosslinked Elastic Cores

118 g of methyl methacrylate is added to the reaction mixture obtained above while maintaining the temperature at 80 ° C. for 1 hour with continuous stirring. In addition, 1.7 g of diisopropylbenzene hydroperoxide in 78 ml of water and 0.42 g of sodium formaldehyde sulfoxylate in 9.58 ml of water are added simultaneously.

After starting to introduce methyl methacrylate, the contents of the reactor were kept at 80 ° C. for 1.5 hours and 0.33 g of t-butyl hydroperoxide and 0.08 g of sodium metabisulpit in 10 ml of water were added to the contents do. The reaction mixture is then maintained at 80 ° C. for 1 hour. At the end of this time, the contents of the reactor are cooled to ambient temperature and the resulting graft copolymer latex is aggregated in a salt solution acidified with concentrated sulfuric acid. The agglomerated product is then filtered, washed and dried to obtain a powder comprising the impact resistance additive.

The conversion of methyl methacrylate during grafting is 96.17%. The impact resistance additive contains a portion of the poly (methyl methacrylate) graft chain that represents 19.82% by weight of the additive and operates at 1300 m.g. It has a viscosity in the molten state corresponding to

Example 10:

1) Preparation of Crosslinked Elastic Core of Impact Resistant Additives

First Step: Preparation of Seeds.

Manufacturing is carried out in a 5 liter reactor equipped with a stirrer and temperature recorder and equipped with a jacket through which the heat transfer fluid passes to maintain the temperature of the reactor.

After degassing 1100 g deionized water and 0.95 g sodium hydrogen carbonate in 95 g of water with nitrogen, they were introduced into the reactor described above, held at ambient temperature and kept under stirring, followed by 4.76 g of sodium dioctyl sulfosuccinate. Nate is dissolved in this mixture as an emulsifier.

The temperature of the reactor contents is then brought to 57 ° C. and then 119 g of n-octyl acrylate and 2.56 g of 1,4-butanediol diacrylate are added to the contents simultaneously while maintaining this temperature.

The temperature of the reactor is brought to 70 ° C., and then 2.62 g of potassium persulfate dissolved in 65 g of water is added to the reaction mixture.

After about 10 minutes of introduction, the temperature rises to 76 ° C. Then 663 g deionized water, 0.66 g sodium bicarbonate in 66 g water, 6.43 g sodium dioctyl sulfosuccinate as emulsifier, 1,071 g n-octyl acrylate and 23.05 g 1,4-butanediol di Acrylate is added to the reactor over 2 hours. The temperature is maintained at 70 ° C. during the addition. The temperature is then increased to 90 ° C. and maintained for 1 hour.

A crosslinked elastic seed, represented by "emulsion (A)", is made up of latex particles of 0.130 μm diameter with a conversion of 99%.

Second step: preparation of the core

Manufacturing is carried out in a 5 liter reactor equipped with a stirrer and temperature recorder and equipped with a jacket through which the heat transfer fluid passes to maintain the temperature of the reactor.

660 g deionized water, 0.66 g sodium bicarbonate in 66 g water, 6.43 g sodium dioctyl sulfosuccinate as emulsifier, 1,071 g n-octyl acrylate and 23.05 g 1,4-butanediol diacrylate To prepare an emulsion premix (B) consisting of.

The reactor was kept at room temperature with stirring, degassed with nitrogen and then introduced with 1,000 g of deionized water and 1 g of sodium bicarbonate in 100 g of water, followed by 338.88 g of emulsion (A) obtained during the first step. Dissolve in the mixture.

The temperature of the contents of the reactor is then brought to 57 ° C. and then 120 g of premix (B) are added while this temperature is maintained.

The temperature of the reactor is set at 70 ° C., and 2.14 g of potassium persulfate dissolved in 65 g of water is added to the reaction mixture.

After about 10 minutes of introduction, the temperature rises to 76 ° C. Then 1505 g of premix (B) are added to the reactor for 110 minutes. 5.95 g of diallyl maleate is then added to the remaining 200 g of Premix B and the combined mixture is added to the contents of the reactor while still maintaining at 70 ° C. over 10 minutes.

The temperature is then increased to 90 ° C. and maintained for 1 hour.

An elastic core constituting latex particles having a Coulter diameter of 0.270 μm at a conversion rate of 99% is obtained.

2. Grafting of Methyl Methacrylate on Crosslinked Elastic Cores

0.54 g of potassium persulfate dissolved in 30 g of water is added to the reaction mixture obtained under stirring while maintaining the temperature at 70 ° C. An emulsion mixture (C) consisting of 200 g of deionized water, 0.35 g of sodium bicarbonate in 35 g of water, 1.34 g of sodium dioctylsulfosuccinate as emulsifier, 267 g of methyl methacrylate and 29.75 g of ethyl acrylate over 45 minutes Add continuously.

After the addition, the contents of the reactor are maintained at 90 ° C. for 1 hour. At the end of this process, the contents of the reactor are cooled to ambient temperature.

A grafted copolymerized latex with a conversion rate of 98.3% is obtained, with an average particle diameter of 0.285 μm.

The latex is then aggregated in a calcium chloride solution. The agglomerated product is filtered, washed and dried to form a powder comprising the impact resistance additive.

This additive is suitable for 890 m.g. of brabender ammeter torque operating under the conditions defined above. Has a viscosity in the molten state.

Example 11 (Not in accordance with the present invention)

For the preparation of the crosslinked elastic core and the seed, a crosslinked elastic core was used to prepare the seed, except that the same weight of 2-ethylhexyl acrylate was used instead of n-octylacrylate, and on the core Preparation is carried out according to the same operating conditions as in Example 10 using the same reactants (grafting agent and crosslinking agent, catalyst, emulsifier, etc.) of the same weight to prepare a shell grafted to.

A graft copolymer latex with a diameter of 0.515 μm is obtained with a conversion of 99.1%.

This latex is then aggregated in a calcium chloride solution. The agglomerates are then filtered, washed and dried to obtain powders which constitute impact resistance additives.

The viscosity of the additive in the molten state is 1,725 m.g. of brabender ammeter torque operating under the conditions described above. Corresponds to

Example 12 (Not in accordance with the present invention)

For the preparation of crosslinked elastic cores and seeds, the seeds were prepared, except that the same molar amount of 1,4-butanediol diacrylate and n-octylacrylate was used instead of the same molar amount relative to butyl acrylate. To the same operating conditions as in Example 10 using a crosslinked elastic core to form the same reactant (grafting agent and crosslinking agent, catalyst, emulsifier, etc.) of the same weight to produce a shell grafted on the core. It manufactures accordingly.

A graft copolymer latex with a diameter of 0.335 μm is obtained with a conversion rate of 98.6%.

This latex is then aggregated in a calcium chloride solution. The agglomerates are then filtered, washed and dried to obtain powders which constitute impact resistance additives.

The viscosity of the additive in the molten state is 1,725 m.g. of torque of the Brabender ammeter operating under the conditions described above. Corresponds to

The properties of the resin composition according to the invention are as follows:

1. The impact resistance strength of the test sample prepared from this resin composition and the production method of the PVC-based resin composition are described below.

The process is carried out under conditions of 25 ° C. in a Papenmeir type mixer of a composition containing (parts by weight) the following components:

100 parts of a vinyl chloride homopolymer having a -K-value of 67,

-2.5 parts of lead phosphite,

-Calcium stearate 1.5 parts,

-6 parts of calcium carbonate,

-TiO ₂ 4 parts,

-1 part of the processing aid (Metablen P550 available from Metablen B.V.),

0.2 parts of -12 stearic acid,

-Loxiol G60 (internal lubricant) 0.3 parts,

-4 parts of polyethylene wax (external lubricant),

X parts of impact resistance additives prepared according to Examples 1-9.

A test sample is prepared from the obtained composition to carry out the impact resistance determination test.

For the preparation of Charpy impact resistance test samples, the PVC resin composition produced from the mixture of the above components was rolled on a Schwanbenthan type rolling mill at 175 ° C. for 6 minutes and then 200 bar pressure at 190 ° C. for 5 minutes at Derragon press. Molded under to form a panel, the panel is cooled in a press.

After cutting the test sample using a rotary saw, notches for notched Charpy impact resistance tests are prepared according to BS standard 2782.

The thickness of the test sample having the shape according to the above-mentioned standard is 2.5 mm.

In order to prepare a test sample for the low temperature impact strength test according to ISO standard 6603.2 1989 (F), the above-mentioned resin composition is mixed in a Krauss-Maffei KMD type 2 screw extruder and introduced into a die to have a thickness of 1 After obtaining a strip of mm, it is cut into 7 cm x 7 cm.

The results were collected and shown in the table below.

In Table 1, the content (phr) per 100 parts by weight of the resin in the raw material of the impact resistance additive (Example) and the PVC resin as described above is indicated in the "impact resistance additive" column. "Charpy impact resistance" strength test is performed according to BS standard 2782 at a temperature of 23 ± 1 ° C. The burst energy is calculated by taking the average of the soft and soft burst energy.

Low temperature impact strength tests are listed in Table 2. As shown in Table 1, the raw materials of the impact resistance additives and their contents (phr) in the PVC resin composition are shown in the column of "impact resistance additives".

In Table 1 and Table 2, the compositions 9 (c), 10 (c), 11 (c), 12 (c), 21 (c) and 22 (c) are not according to the present invention.

2. Preparation of the resin composition based on poly (butylene terephthalate) (PBT) was as described below, and the impact resistance strength characteristics of the test sample prepared from this resin composition is shown below.

The preparation of a resin composition according to the invention containing (parts by weight) the following components is carried out at 25 ° C:

80 parts of a poly (butylene terephthalate) homopolymer (Celanex 1700A, sold by Hoechst Celanese),

20 parts impact resistance additives prepared according to one of Examples 10-12.

The mixture is dried at 80 ° C. under vacuum of 1 bar for at least 10 hours.

The mixture is extruded in a Buss PR46 Ko-stirrer to homogenize and then the resulting rod is granulated. Extrusion conditions are as follows:

Ko-stirrer temperature of screw: 230 ° C

Zone 1 temperature: 260 ° C

Zone 2 temperature: 250 ° C.

Speed: 120 revolutions / minute

Extruder-Screw temperature: 240 ℃

Zone 1 temperature: 240 ° C

Die: 230 ℃

Speed: 94 revolutions / minute

Samples for Izod impact resistance test are prepared by injection molding the obtained granules in a Visumat 5000 injection molding machine. These granules are dried at 80 ° C. under vacuum of 1 bar for at least 10 hours. Injection is carried out under the following conditions:

Injection temperature: 240 ℃

Injection rate: 10%

Injection pressure: 80 bar

Holding pressure: 50 bar

Retention time: 20 seconds

The sample of the shape and thickness as described in ISO standard 180 is notched.

The results obtained are shown in the table below. In Table 3, the raw materials of impact resistance additives (examples) are shown in the column of "impact resistance additives". The burst energy according to ISO standard 180 at a temperature of 23 ± 1 ° C., calculated by taking the average of flexible and soft bursts for 10 test samples, is described in the “Ambient temperature impact resistance” column. The burst energy according to ISO standard 180 at a temperature of -20 ± 1 ° C, calculated by taking the average of the soft and soft bursts for the ten test samples, is described in the "Frozen Impact Resistance" column.

3. Preparation of the resin composition based on poly (1,1-difluoroethylene) (PVDF) was as described below, and the impact resistance characteristics of the test sample prepared from this resin composition are shown below.

The preparation of a resin composition according to the invention containing (parts by weight) the following components is carried out at 25 ° C:

95 parts of a poly (1,1-difluoroethylene) homopolymer (Kynar 1000, sold by ELF ATOCHEM S. A.),

5 parts impact resistance additives prepared according to Examples 10 and 12.

The mixture is extruded in Werner 40 to homogenize and the resulting rods are granulated. Extrusion conditions are as follows:

Zone 1 temperature: 195 ° C

Zone 2 temperature: 230 ° C

Temperature in zone 3: 215 ° C

Temperature in zone 4: 240 ° C

Samples for Izod impact resistance and Charpy impact resistance test samples are prepared by injection molding the obtained granules in a Visumat 5000 injection molding machine in a sheet shape of 100 mm × 100 mm. Samples of the shape and thickness as described in ISO Standard 179 and ISO Standard 180 were punched out with the tool.

The results obtained are shown in Table 4 below. In Table 4, the raw materials of impact resistance additives (examples) are shown in the column of "impact resistance additives". The burst energy according to ISO standard 180 at a temperature of 23 ± 1 ° C., calculated by taking the average of flexible and soft bursts for 10 test samples, is described in the “Ambient temperature impact resistance IZOD” column. The burst energy according to ISO standard 179 at a temperature of 23 ± 1 ° C., calculated by taking the average of flexible and soft bursts for 10 test samples, is described in the “Ambient temperature impact resistance CHARPY” column. The burst energy according to ISO standard 179 at a temperature of −40 ± 1 ° C., calculated by taking the average of flexible and soft bursts for 10 test samples, is described in the “Frozen Impact Resistance CHARPY” column.

Composition Impact resistance additives CHARPY impact resistance Raw Material (Examples) Content (phr) Bursting Energy (KJ / M ³ ) Ductile rupture% One One 7 34.2 60 2 One 7.5 〉 52 100 3 3 7 48 100 4 3 7.5 〉 52 100 5 4 7 46.5 100 6 4 7.5 〉 52 100 7 2 7 43.1 80 8 2 8 52 100 9 (c) 6 7 15.7 0 10 (c) 6 8 48.6 90 11 (c) 7 7 12.4 0 12 (c) 7 7.5 39 70 13 8 7 15.2 0 14 8 7.5 〉 51 100 15 9 7 〉 43 100 16 9 7.5 〉 52 100

Composition Impact resistance additives Low temperature impact resistance Raw material (Example) Content (phr) Experiment temperature (℃) Bursting Energy (KJ / M ³ ) 17 One 6 -10 23.1 -20 19.5 -30 11.5 -40 9.1 18 3 6 -10 22.6 -20 20.8 -30 5 -40 - 19 4 6 -10 25.6 -20 19.6 -30 8.2 -40 2.4 20 5 6 -10 25.9 -20 19.3 -30 7.6 -40 4.6 21 (c) 7 6 -10 18 -20 17 -30 5.4 -40 2.5 22 (c) 6 6 -10 22 -20 15 -30 5.1 -40 2.1

Impact resistance additives Ambient Temperature Impact Resistance (kJ / m ² ) Refrigeration Impact Resistance (kJ / m ² ) PBT * 69.3 11.3 Example 10 62 16.1 Example 11 56.8 8.4 Example 12 74 8.8

* PBT base composition (no impact resistance additive)

Impact resistance additives Ambient temperature IZOD impact resistance (kJ / m ² ) Ambient temperature CHARPY impact resistance (kJ / m ² ) Frozen CHARPY Impact Resistance (kJ / m ² ) PVDF * 7.5 8 3.7 Example 10 62.8 78.2 15.6 Example 11 49.3 60.3 11.1

PVDF base composition (no impact resistance additive)

As described above, the present invention provides a core / shell type impact resistance additive for thermoplastic polymers having excellent impact strength.

Claims (59)

Core / shell type impact resistance additive consisting of a core based on alkyl acrylate or polyorganosiloxane rubber and a shell based on poly (alkyl methacrylate) or a shell based on styrene-acrylonitrile copolymer, impact resistant additives comprising a) and b): a) 70 to 90% by weight of a crosslinked elastic core consisting of the following 1) and 2): 1) Copolymer (I) of n-alkyl acrylate having an alkyl group having 5 to 12 carbon atoms or a mixture of alkyl acrylates having a straight or branched chain alkyl group having 2 to 12 carbon atoms, containing an unsaturated group in the molecule 20% to 100% by weight of a nucleus consisting of a multifunctional crosslinker having at least one CH ₂ = C <vinyl type and optionally containing an unsaturated group in the molecule and at least one of which is a CH ₂ = CH-CH ₂ -allyl type Wherein the nucleus contains a crosslinking agent and a graft agent that may be contained in an amount of 0.05 mol% to 5 mol%; 2) a copolymer (II) of n-alkyl acrylate having an alkyl group having 4 to 12 carbon atoms or a mixture of alkyl acrylates as defined in 1) above, and an unsaturated group in the molecule, at least one of which is CH ₂ = 80% by weight to 0% by weight of a sheath consisting of a CH-CH ₂ -allyl multifunctional graft agent, provided that the sheath contains the graft agent in an amount of 0.05 mol% to 2.5 mol%; b) a polymer of alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms or optionally an alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms, and an alkyl acrylate having an alkyl group having 1 to 8 carbon atoms A shell composed of a random copolymer of (in this case containing an alkyl acrylate in an amount of 5 mol% to 40 mol%), or optionally composed of a styrene-acrylonitrile copolymer, grafted onto the core 30 Weight% to 10 weight%. The impact resistant additive according to claim 1, comprising the following a) and b): a) 75 to 85% crosslinked elastic core, and b) 25-15% of the shell grafted onto the core. The number of carbon atoms of the alkyl group of n-alkyl acrylate in copolymer (I) is 5-8, and the number of carbon atoms of the alkyl group of n-alkyl acrylate in copolymer (II) is 4-8. Impact resistance additives of from 8 to 8. The impact resistance additive according to claim 1 or 2, wherein the alkyl group of the alkyl acrylate has 4 to 8 carbon atoms in the mixture forming part of the copolymer (I) and / or the copolymer (II). The impact resistant additive according to claim 1, wherein the crosslinking agent is selected from a derivative containing two or more CH ₂ = C <vinyl double bonds. The impact resistance additive according to claim 1, wherein the crosslinking agent is selected from derivatives containing at least one double bond of CH ₂ = CH-CH ₂ -allyl type and at least one double bond of vinyl type. The impact resistance additive according to claim 1 or 5, wherein the crosslinking agent is 1,4-butanediol diacrylate. The impact resistance additive according to claim 1 or 6, wherein the crosslinking agent is allyl acrylate or methacrylate. The impact resistance additive according to claim 1, wherein the graft agent is selected from a derivative containing two or more double bonds of CH ₂ = CH-CH ₂ -allyl type. The impact resistant additive according to claim 1, wherein the graft agent is selected from derivatives containing at least one vinyl double bond and at least one allyl double bond. The impact resistant additive according to claim 1 or 9, wherein the graft agent is diallyl maleate. The impact resistant additive according to claim 1 or 10, wherein the graft agent is allyl acrylate or methacrylate. The impact resistant additive according to any one of claims 1, 2, 5, 6, 9 or 10, wherein the nucleus of the crosslinked core contains from 0.5 mol% to 1.5 mol% crosslinker and optionally graft agent. The impact resistant additive according to claim 1, wherein the shell of the crosslinked core contains from 0.5 mol% to 1.5 mol% of graft agent. The impact resistant additive according to claim 1 or 2, wherein the random copolymer of the shell contains 10 mol% to 20 mol% of the graft agent. The n-alkyl acrylate used to prepare copolymer (I) is n-pentyl acrylate, n-hexyl acrylate, n-heptyl acrylate and n-octyl acryl. Impact-resistant additive that is late. The n-alkyl acrylate used to prepare the copolymer (II) is n-butyl acrylate, n-pentyl acrylate, n-hexyl acrylate, n-heptyl acryl. Impact-resistant additives that are late and n-octyl acrylate. The impact resistance additive according to claim 16, wherein the n-alkyl acrylate for producing copolymers (I) and (II) is n-pentyl acrylate. The impact resistance additive according to claim 16, wherein the n-alkyl acrylate for producing copolymers (I) and (II) is n-hexyl acrylate. The impact resistance additive according to claim 16, wherein the n-alkyl acrylate for producing copolymers (I) and (II) is n-heptyl acrylate. The impact resistance additive according to claim 16, wherein the n-alkyl acrylate for producing copolymers (I) and (II) is n-octyl acrylate. The impact resistant additive according to claim 16, wherein the alkyl acrylate for producing copolymer (I) is n-octyl acrylate and the n-alkyl acrylate for producing copolymer (II) is n-butyl acrylate. The straight or branched chain alkyl acrylate according to claim 1 or 2, which forms a mixture of alkyl acrylates used to prepare the copolymers (I) and / or (II), is ethyl acrylate, n-. Propyl acrylate, n-butyl acrylate, amyl acrylate, 2-methylbutyl acrylate, 2-ethylhexyl acrylate, n-hexyl acrylate, n-octyl acrylate, n-decyl acrylate, n-dodecyl Impact resistance additives that are acrylates and 3,5,5-trimethylhexyl acrylate. The impact resistant additive according to claim 23, wherein the n-alkyl acrylate is used in an amount of at least 10% by weight of the mixture of alkyl acrylates. 25. The impact resistant additive according to claim 24, wherein n-alkyl acrylate is used in an amount of 20 to 80% by weight of the mixture of alkyl acrylates. The impact resistance additive of claim 23 wherein the n-alkyl acrylate is n-octyl acrylate. The impact resistant additive according to claim 1 or 2, wherein the alkyl methacrylate used to form the shell is methyl methacrylate. A thermoplastic polymer composition comprising the impact resistance additive of claim 1. 29. The process according to claim 28, characterized in that the thermoplastic polymer consists of polymers in the form of one or several polycondensates, in particular polyesters such as poly (butylene terephthalate), polyamides, polyesteretheramides and alloys of said polymers. Composition. 29. The process of claim 28 wherein the thermoplastic polymer is selected from the group consisting of poly (alkyl methacrylates), in particular poly (methyl methacrylates); Vinyl chloride homopolymers that can be overchlorinated; As a result of copolymerization of one or several ethylenically unsaturated comonomers with vinyl chloride, a copolymer containing at least 80% by weight of polymerized vinyl chloride; 1,1-dichloroethylene homopolymer; Or 1 or several polymers selected from 1,1-difluoroethylene homopolymers. 31. The composition of claim 30, wherein the thermoplastic polymer is a vinyl chloride homopolymer. 30. The composition of claim 29 wherein the thermoplastic polymer is poly (butylene terephthalate). 33. The composition of any of claims 28-32, wherein the content of impact resistance additive is from 1 to 30 parts by weight per 100 parts by weight of thermoplastic polymer used. 34. The composition of claim 33 wherein the content of impact resistance additive is from 5 to 10 parts by weight per 100 parts by weight of thermoplastic polymer used. Claim 1, characterized in that in the first step a crosslinked elastic core consisting of the nucleus and the shell is prepared and in a second step a shell made of poly (alkyl methacrylate) is grafted onto the crosslinked elastic core. Method for preparing the impact resistance additive claimed in the claims. 31. The composition of claim 30, wherein the thermoplastic polymer is a 1,1-difluoroethylene homopolymer. The impact resistant additive according to claim 1, wherein the content of the core (1) in the crosslinked elastic core (a) is 20 to 90% by weight. The impact resistant additive according to claim 1, wherein the content of the shell (2) in the crosslinked elastic core (a) is from 80% by weight to 10% by weight. The impact resistance additive according to claim 3, wherein the alkyl group of the alkyl acrylate has 4 to 8 carbon atoms in the mixture forming part of the copolymer (I) and / or the copolymer (II). 4. The impact resistant additive according to claim 3, wherein the nucleus of the crosslinked core contains from 0.5 mole% to 1.5 mole% of a crosslinking agent and optionally a graft agent. The impact resistant additive according to claim 4, wherein the nucleus of the crosslinked core contains from 0.5 mol% to 1.5 mol% crosslinking agent and optionally graft agent. 8. The impact resistant additive according to claim 7, wherein the nucleus of the crosslinked core contains from 0.5 mol% to 1.5 mol% of a crosslinking agent and optionally a graft agent. 9. The impact resistant additive according to claim 8, wherein the nucleus of the crosslinked core contains from 0.5 mol% to 1.5 mol% crosslinking agent and optionally graft agent. 12. The impact resistant additive according to claim 11, wherein the nucleus of the crosslinked core contains from 0.5 mol% to 1.5 mol% of a crosslinking agent and optionally a graft agent. 13. The impact resistant additive according to claim 12, wherein the nucleus of the crosslinked core contains from 0.5 mole% to 1.5 mole% of a crosslinking agent and optionally a graft agent. The impact resistant additive according to claim 4, wherein the shell of the crosslinked core contains 0.5 mol% to 1.5 mol% of the graft agent. 12. The impact resistant additive according to claim 11, wherein the shell of the crosslinked core contains from 0.5 mole% to 1.5 mole% of the graft agent. 13. The impact resistant additive according to claim 12, wherein the shell of the crosslinked core contains from 0.5 mole% to 1.5 mole% of the graft agent. 4. The impact resistant additive according to claim 3, wherein the random copolymer of the shell contains 10 mol% to 20 mol% of the graft agent. The impact resistant additive according to claim 4, wherein the random copolymer of the shell contains 10 mol% to 20 mol% of the graft agent. 4. Impact resistance according to claim 3, wherein the n-alkyl acrylates used to prepare copolymer (I) are n-pentyl acrylate, n-hexyl acrylate, n-heptyl acrylate and n-octyl acrylate additive. 4. The n-alkyl acrylate used to prepare copolymer (II) is n-butyl acrylate, n-pentyl acrylate, n-hexyl acrylate, n-heptyl acrylate and n-. Impact resistant additive that is octyl acrylate. 18. The impact resistant additive according to claim 17, wherein the n-alkyl acrylates for preparing copolymers (I) and (II) are n-pentyl acrylates. 18. The impact resistant additive according to claim 17, wherein the n-alkyl acrylates for producing copolymers (I) and (II) are n-hexyl acrylates. 18. The impact resistant additive according to claim 17, wherein the n-alkyl acrylate for the preparation of copolymers (I) and (II) is n-heptyl acrylate. 18. The impact resistant additive according to claim 17, wherein the n-alkyl acrylate for producing copolymers (I) and (II) is n-octyl acrylate. 18. The impact resistant additive according to claim 17, wherein the alkyl acrylate for producing copolymer (I) is n-octyl acrylate and the n-alkyl acrylate for producing copolymer (II) is n-butyl acrylate. The straight or branched chain alkyl acrylate according to claim 3, which forms a mixture of alkyl acrylates used to prepare copolymers (I) and / or (II), is ethyl acrylate, n-propyl acrylate, n-butyl acrylate, amyl acrylate, 2-methylbutyl acrylate, 2-ethylhexyl acrylate, n-hexyl acrylate, n-octyl acrylate, n-decyl acrylate, n-dodecyl acrylate and 3 Impact resistant additive that is, 5,5-trimethylhexyl acrylate. 26. The impact resistant additive according to claim 24 or 25, wherein the n-alkyl acrylate is n-octyl acrylate.