JP2013528243A - Encapsulated flame retardant for polymer - Google Patents

Abstract

  The present invention relates to a process for producing particles containing at least one halogen-free flame retardant and at least one metal oxide or metalloid oxide, wherein the particles comprise a flame retardant in the core and a metal in the shell. It may be a core-shell particle with an oxide or metalloid oxide or a particle with an essentially uniform distribution of flame retardant and metal oxide or metalloid oxide. Furthermore, the present invention relates to particles containing at least one halogen-free flame retardant and at least one metal oxide or metalloid oxide, said particles and a polymer containing at least one thermoplastic polymer or thermosetting polymer. The molding material and the use of the particles in polymer molding materials or the use of the particles to impart flame retardancy to the polymer molding materials.

Description

  The present invention relates to a process for producing particles containing at least one halogen-free flame retardant and at least one metal oxide or metalloid oxide, wherein the particles comprise a flame retardant in the core and a metal in the shell. It may be a core-shell particle with an oxide or metalloid oxide or a particle with an essentially uniform distribution of flame retardant and metal oxide or metalloid oxide. Furthermore, the present invention relates to particles containing at least one halogen-free flame retardant and at least one metal oxide or metalloid oxide, the particles and polymers containing at least one thermoplastic polymer or thermosetting polymer. It relates to a molding material, as well as to the use of said particles in polymer molding materials, or the use of said particles for imparting flame retardancy to polymer molding materials.

  Composite materials containing flame retardants and other materials are already known from the state of the art.

  PMSE Preprints (2008), 98, 533-535 discloses microcapsules having a core-shell structure. As a flame retardant, the core of the microcapsule contains tris (2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane-1-oxo-4-methanol) phosphate (trimer). ) Exists. The shell of this microcapsule is formed of melamine resin.

  Japanese Patent Application Laid-Open No. 2000-263733 discloses a method for impregnating a fibrous substrate with a phenol resin containing phosphate-containing microcapsules.

  Donghua Daxue Xuebao, Ziran Kexue Ban (2007), 33 (6), 701-705 includes water-soluble dimethylmethylphosphonate (DMMP) as a core material and PVA and GA (glutar as a shell material) obtained by an emulsification method. Core-shell particles containing products from the acetalization of aldehydes are disclosed.

From the state of the art, particles containing halogen-free, preferably water-insoluble flame retardants in combination with at least one metal oxide or metalloid oxide, for example SiO ₂ , TiO ₂ and / or ZnO, are known is not. Further, for example, a method of forming silica by a sol-gel method is not disclosed at all.

  Therefore, the problem of the present invention compared to the state of the art is to combine a liquid, halogen-free flame retardant with a metal oxide or metalloid oxide and convert it into a free flowing powder. is there. The combined liquid, halogen-free flame retardant can then advantageously be used in polymer molding materials.

This task is at least the following steps:
(A) producing an aqueous emulsion containing at least one flame retardant and at least one precursor compound of at least one metal oxide or metalloid oxide;
(B) forming a core-shell type particle, wherein at least one flame retardant is present in the core of the particle and at least one metal oxide or metalloid oxide is present in the shell of the particle; And (C) optionally drying the core-shell type particles from step (B),
Or (D) producing a mixture containing water, at least one polar solvent, at least one halogen-free flame retardant and at least one precursor compound of at least one metal oxide or metalloid oxide,
(E) converting at least one precursor compound of at least one metal oxide or metalloid oxide into at least one metal oxide or metalloid oxide, at least one metal oxide or metalloid oxide and at least At least one halogen-free flame retardant and at least one metal comprising the steps of obtaining particles containing one halogen-free flame retardant, and (F) optionally drying the particles from step (E) This is solved by the process according to the invention for producing particles containing oxides or metalloid oxides.

The individual steps of the two alternative methods according to the invention are described in detail below:
The process 1 according to the invention for producing particles containing at least one halogen-free flame retardant and at least one metal oxide or metalloid oxide comprises at least the following steps:
(A) producing an aqueous emulsion containing at least one flame retardant and at least one precursor compound of at least one metal oxide or metalloid oxide;
(B) forming a core-shell type particle, wherein at least one flame retardant is present in the core of the particle and at least one metal oxide or metalloid oxide is present in the shell of the particle; And (C) optionally drying the core-shell particles from step (B).

Step (A):
Step (A) of Method 1 according to the invention comprises the preparation of an aqueous emulsion containing at least one flame retardant and at least one precursor compound of at least one metal oxide or metalloid oxide.

  According to the invention, a halogen-free flame retardant is used which is preferably insoluble in water. Furthermore, in a preferred embodiment, the present invention uses a halogen-free flame retardant which is liquid at standard conditions, ie a temperature of 25 ° C. and a pressure of about 1 bar (a).

  In another embodiment, the flame retardant that can be used according to the present invention is solid under standard conditions, but melts below 100 ° C. The flame retardant that can be used according to the invention is generally insoluble in water.

  “Halogen-free” means within the scope of the invention that the flame retardant that can be used according to the invention does not contain any halogen, ie atoms selected from fluorine, chlorine, bromine, iodine. Within the scope of the present invention "free of atoms" means that the amount of atoms stated is below the analytical detection limit.

  Preferred flame retardants according to the present invention are liquid, halogen-free P-containing flame retardants. This flame retardant is generally known to those skilled in the art.

〔式中、Ｒ¹、Ｒ²、Ｒ³、Ｒ⁴、Ｒ⁵、Ｒ⁶、Ｒ⁷、Ｒ⁸、Ｒ⁹、Ｒ¹⁰、Ｒ¹¹、Ｒ¹²、Ｒ¹³、Ｒ¹⁴、Ｒ¹⁵、Ｒ¹⁶、Ｒ¹⁷、Ｒ¹⁸、およびＸは、互いに無関係に次の意味を有する：
Ｒ¹、Ｒ²、Ｒ³、Ｒ⁴、Ｒ⁵、Ｒ⁶、Ｒ⁷、Ｒ⁸、Ｒ⁹、Ｒ¹⁰、Ｒ¹¹、Ｒ¹²、Ｒ¹³、Ｒ¹⁴、Ｒ¹⁵、Ｒ¹⁶、Ｒ¹⁷、Ｒ¹⁸は、互いに無関係に、水素、ヒドロキシル基、または場合により官能基を有するアリール基、アルキル基および／またはシクロアルキル基を表わし、
Ｘは、互いに無関係に、酸素または硫黄を表わす〕に相応して使用される。 Particularly advantageously, the flame retardant according to the invention has the following formulas (I) to (VI):

^{Wherein, R 1, R 2, R} 3, R 4, R 5, R 6, R 7, R 8, R 9, R 10, R 11, R 12, R 13, R 14, R 15, R ¹⁶ , R ¹⁷ , R ¹⁸ , and X have the following meanings independently of each other:
^{R 1, R 2, R 3} , R 4, R 5, R 6, R 7, R 8, R 9, R 10, R 11, R 12, R 13, R 14, R 15, R 16, R 17 R ¹⁸ independently of one another represents hydrogen, a hydroxyl group, or optionally an aryl group, alkyl group and / or cycloalkyl group having a functional group;
X represents oxygen or sulfur independently of each other].

An aryl group is, according to the invention, a group having a basic skeleton of 6 to 30 carbon atoms, preferably 6 to 18 carbon atoms, which can be a single aromatic ring or a plurality of fused rings. Formed from the aromatic ring. Suitable basic skeletons are, for example, phenyl, naphthyl, anthracenyl or phenanthrenyl. The basic skeleton may be unsubstituted, i.e., all carbon atoms that can be substituted have hydrogen atoms or are substituted at one, more than one, or all substitutable positions of the basic skeleton. It's okay. Suitable substituents are, for example, alkyl groups, preferably alkyl groups having 1 to 8 carbon atoms, particularly preferably methyl, ethyl or isopropyl, aryl groups, preferably C ₆ -C ₂₂ aryl groups, particularly preferably C ₆ -C ₁₈ aryl group, particularly preferably C ₆ -C ₁₄ aryl group, i.e. phenyl, naphthyl, phenanthrenyl or having a basic skeleton of anthracenyl, further substituted or may be or aryl group need not be substituted A heteroaryl group, preferably a heteroaryl group containing at least one nitrogen atom, particularly preferably a pyridyl group, an alkenyl group, preferably an alkenyl group having a double bond, particularly preferably one double bond and 1 It is an alkenyl group having ˜8 carbon atoms.

  Particularly preferred aryl groups are those selected from the group consisting of phenyl, alkyl substituted phenyl, naphthyl or alkyl substituted naphthyl.

  An alkyl group is, according to the invention, preferably a group having 1 to 20 carbon atoms, particularly preferably 1 to 10 carbon atoms, particularly preferably 1 to 8 carbon atoms. The alkyl group may be branched or unbranched and may optionally be interrupted by one or more heteroatoms. In addition, the alkyl group may be substituted with one or more substituents described in connection with the aryl group. Similarly, an alkyl group can have one or more aryl groups. In this case, all of the aforementioned aryl groups are suitable. Furthermore, it is possible for the alkyl group or groups to have one or more functional groups, preferably a hydroxyalkyl group or a cyanoalkyl group.

  Particularly preferred alkyl groups are those selected from the group consisting of methyl, ethyl, propyl, such as n-propyl, isopropyl, butyl, such as n-butyl, isobutyl, tert-butyl, octyl and isomers thereof.

  Cycloalkyl groups according to the invention preferably have 3 to 20 carbon atoms, particularly preferably 3 to 10 carbon atoms, particularly preferably 3 to 8, for example 3, 4, 5 or It is a cyclic group having 6 carbon atoms. The cycloalkyl group may be substituted or unsubstituted and optionally interrupted by one or more heteroatoms, preferably N, O, Si or S. Cycloalkyl groups can be substituted with one or more substituents described in connection with aryl groups. Similarly, a cycloalkyl group can have one or more aryl groups. In this case, all the aryl groups described above are suitable. Furthermore, it is possible for one or more cycloalkyl groups to have one or more functional groups.

  Particularly preferred cycloalkyl groups are those selected from the group consisting of cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and their alkyl substituted derivatives.

According to the invention, all groups described as R ^{1 to} R ¹⁸ can have functional groups.

  According to the invention, suitable functional groups consist, for example, of carbonyl groups, preferably carboxylic acid groups, keto groups, aldehyde groups, ester groups, amino groups, amide groups, hydroxy groups, cyano groups, thio groups or SCN groups. Selected from the group.

According to the invention, particularly preferred compounds of the general formulas (I) to (VI) are thiophenylphosphine (formula (I), R ¹ , R ² and R ³ are phenyl), diphenyl (o- Toluyl) phosphine (formula (I), R ¹ , R ² is phenyl and R ³ is o-toluyl), tributylphosphine oxide (formula (III), R ⁷ , R ⁸ and R ⁹ are Butyl and X is oxygen), trioctyl phosphine oxide (formula (III), R ⁷ , R ⁸ and R ⁹ are octyl and X is oxygen), diphenyl phosphite (formula ( V), R ¹³ and R ¹⁵ are phenyl, R ¹⁴ is hydrogen and X is oxygen), triphenyl phosphite (formula (II), R ⁷ , R ⁸ and R ⁹ are Phenyl), tris (nonylphenyl) phos Aito (formula (II), R ^7, R ⁸ and R ⁹ are nonylphenyl) dimethyl methyl phosphonate (formula (V), R ^13, R ¹⁴ and R ¹⁵ are methyl, X is oxygen Dioctyl phenyl phosphonate (formula (V), R ¹³ and R ¹⁵ are octyl, R ¹⁴ is phenyl and X is oxygen), triphenyl phosphate (formula (VI), R ¹⁶ , R ¹⁷ and R ¹⁸ are phenyl and X is oxygen), tritoluyl phosphate (formula (VI), R ¹⁶ , R ¹⁷ and R ¹⁸ are o-toluyl and X is oxygen And a mixture thereof.

〔式中、Ｒ¹⁹、Ｒ²⁰、Ｒ²¹、Ｒ²²、Ｒ²³、Ｒ²⁴、Ｒ²⁵、Ｒ²⁶、Ｘ、Ｑ、Ｌｎおよびｍは、互いに無関係に、次の意味を有する：
Ｒ¹⁹、Ｒ²⁰、Ｒ²¹、Ｒ²²、Ｒ²³、Ｒ²⁴、Ｒ²⁵およびＲ²⁶は、互いに無関係に、水素または場合により官能基を有するアリール基、アルキル基および／またはシクロアルキル基を表わし、
Ｘは、互いに無関係に酸素および硫黄を表わし、
ＱおよびＬは、互いに無関係に、Ｐ原子の結合を生じるかまたは他の基ＱまたはＬへの結合を生じる、少なくとも２個のヒドロキシ官能基を有する有機基を表わす〕に相応して使用されてよい。 Furthermore, according to the invention, preferred flame retardants are the following formulas (VII) and / or (VIII):

[Wherein R ¹⁹ , R ²⁰ , R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ , R ²⁶ , X, Q, Ln and m have the following meanings independently of each other:
R ¹⁹ , R ²⁰ , R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ and R ²⁶ each independently represent hydrogen or an aryl group, alkyl group and / or cycloalkyl group having a functional group. ,
X represents oxygen and sulfur independently of one another;
Q and L represent organic groups having at least two hydroxy functional groups which, independently of each other, result in the bonding of P atoms or the bonding to other groups Q or L] Good.

  In a preferred embodiment of the process according to the invention, Q and / or L in the compounds of the general formula (VII) or (VIII), independently of one another, resorcinol, hydroquinone, bisphenol A, bisphenol F, polycarbonate with hydroxy end groups Segments such as phenol groups, and mixtures thereof. In this compound, the hydrogen atom is separated upon bonding to P. This is known to those skilled in the art.

  Regarding the aryl group, alkyl group and / or cycloalkyl group present in the compound of the general formula (VII) or (VIII), what has been said in relation to the compounds (I) to (VI) is applicable.

R ¹⁹ , R ²⁰ , R ²¹ and R ²² are preferably phenyl or alkyl-substituted phenyl. R ²³ , R ²⁴ , R ²⁵ and R ²⁶ are preferably methyl, phenol, phenyl or alkyl-substituted phenyl.

  n generally represents an integer of 1 to 100, preferably 1 to 10, independently of one another.

  m generally represents an integer of 1 to 1000, preferably 1 to 25, independently of one another.

  The flame retardant additives according to general formulas (VII) and (VIII) may be present as individual compounds or preferably as a mixture of compounds having different values for n and m.

According to the invention, particularly preferred compounds of the general formula (VI) or (VII) are resorcinol-bis (diphenylphosphate) (formula (VII), R ¹⁹ , R ²⁰ , R ²¹ and R ²² are phenyl Yes, X is oxygen, Q is resorcinol, n is 1-7, bisphenol A-bis (diphenyl phosphate) (formula (VII), R ¹⁹ , R ²⁰ , R ²¹ and R ²² is phenyl, X is oxygen, Q is bisphenol A, n is 1 to 5), poly (m-phenylenemethyl) phosphonate (formula (VIII), R ²³ , R ²⁶ is phenol, R ²⁴ and R ²⁵ are methyl, L is resorcinol and X is oxygen) and mixtures thereof.

  According to the present invention, at least one metal oxide or metalloid oxide is present in the produced particles. According to the invention, all metal oxides or metalloid oxides known to the person skilled in the art that are suitable for the production of particles containing at least one flame retardant may be used.

In a preferred embodiment, at least one metal oxide or metalloid oxide selected from metal oxides or metalloid oxides can be produced by a sol-gel process known to those skilled in the art. In a particularly preferred embodiment, the at least one metal oxide or metalloid oxide is selected from the group consisting of SiO ₂ , TiO ₂ , ZnO, ZrO ₂ , Al ₂ O ₃ and mixtures thereof.

  The described metal oxide and metalloid oxide precursor compounds are preferably individual monomer units, or the precursor compounds are composed of a number of monomer units.

In a particularly preferred embodiment, SiO ₂ is used in the process according to the invention.

  The at least one precursor compound of at least one metal oxide or metalloid oxide is a compound that can be converted into the corresponding metal oxide or metalloid oxide by a sol-gel method known to those skilled in the art. In general, all precursor compounds that can be converted to the desired metal oxide or metalloid oxide by the described sol-gel method are suitable.

〔式中、Ｒ²⁷、Ｒ²⁸、Ｒ²⁹およびＲ³⁰は、互いに無関係に、水素、アルキル基、アリール基、アルキルオキシ基および／またはアリールオキシ基を表わす〕で示される化合物が使用される。 In a preferred embodiment, the precursor compound for SiO _{2 has} the general formula (IX):

[Wherein, R ²⁷ , R ²⁸ , R ²⁹ and R ³⁰ independently represent hydrogen, an alkyl group, an aryl group, an alkyloxy group and / or an aryloxy group] are used.

  With respect to the alkyl group and / or the aryl group in the compound of the general formula (IX), the above description is applicable. According to the present invention, the alkyloxy group and / or aryloxy group optionally present in the compound of general formula (IX) is the alkyl group and / or aryl group described and said group via an oxygen atom. A distinction is made in terms of bonding to Si atoms.

Particularly preferably, in the compound of general formula (IX), R ²⁷ , R ²⁸ , R ²⁹ and R ³⁰ independently of one another are hydrogen, methyl, ethyl, propyl, such as n-propyl, isopropyl, butyl, such as n- It is selected from butyl, isobutyl, tert-butyl, phenyl, methoxy, ethoxy, propoxy, such as n-propoxy, isopropoxy, butoxy, such as n-butoxy, isobutoxy, tert-butoxy or phenoxy.

Particularly preferred precursor compounds for SiO ₂ are tetraalkoxysilanes such as tetramethoxysilane (TMOS), tetraethoxysilane (TEOS), methyltrialkoxysilanes such as methyltrimethoxysilane (MTMS), methyltriethoxysilane. (MTES), phenyltrialkoxysilane, such as phenyltrimethoxysilane (PTMS), phenyltriethoxysilane, and mixtures thereof. According to the invention, preferably a mixture of two or more of the compounds described is used, for example a mixture of tetraethoxysilane (TEOS) and phenyltriethoxysilane (PTES). In this particularly advantageously used mixture, the quantity ratio of TEOS to PTES is, for example, 1: 1 to 10: 1, preferably 6: 1 to 3: 1.

  Step (A) of Method 1 according to the invention comprises the preparation of an aqueous emulsion containing at least one flame retardant in at least one precursor compound of at least one metal oxide or metalloid oxide.

  The production of the emulsion in step (A) can generally be carried out by methods known to those skilled in the art for producing emulsions, for example by mixing the individual components in corresponding amounts.

  The emulsion produced in step (A) of the process according to the invention is aqueous, i.e. the predominant solvent or dispersant present is water.

In a preferred embodiment, the aqueous emulsion according to step (A) is, for example, an alcohol ethoxylate, such as C ₁₂ alcohol, such as C ₁₂ H ₂₅ (OCH ₂ CH ₂ O) ₆ OH, an alkylphenol ethoxylate, such as octyl-phenol- At least one selected from the group consisting of ethoxylates, fatty acid ethoxylates such as RCOO— (CH ₂ CH ₂ O) _n H, wherein R = 12-18, and mixtures thereof It is possible to contain two surfactants, particularly preferably nonionic surfactants.

  Typical nonionic surfactants suitable for the emulsions according to the invention as emulsifiers are, for example, sorbitan esters and their ethoxylated derivatives, fatty acid esters of sorbitan (so-called Span) and their ethoxylated derivatives (so-called Tween). ), For example, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan monostearate.

  When a nonionic surfactant or a mixture of nonionic surfactants is used according to the present invention, the concentration of the one or more nonionic surfactants is determined according to the present invention by at least one water-insoluble 0.05 to 5% by weight, preferably 0.5 to 2% by weight, respectively, with respect to the water-immiscible phase formed by the flame retardant.

  Further preferably, the aqueous emulsion described in step (A) can contain at least one non-polar solvent. However, the presence of a nonpolar solvent is not necessary when using a flame retardant that is predominantly dissolved in at least one metal oxide or metalloid oxide precursor compound.

  Solvents having a dielectric constant less than 15 are commonly referred to by those skilled in the art as nonpolar solvents.

  In a preferred embodiment of the process according to the invention, the nonpolar solvent optionally used in step (A) is a solvent which has a low dielectric constant, for example below 15, and is immiscible with water. “Water-immiscible” means that two phases are continuously formed upon mixing with water.

Examples of nonpolar solvents which are advantageously used according to the invention are benzene (C ₆ H ₆ ), carbon tetrachloride (CCl ₄ ), diethyl ether (CH ₃ CH ₂ OCH ₂ CH ₃ ), pentane, cyclopentane, hexane , Cyclohexane, toluene, 1,4-dioxane, chloroform, tetrahydrofuran, dichloromethane and mixtures thereof.

  The individual components of the emulsion described in step (A) of method 1 according to the invention may generally be mixed with one another in each possible order.

  In a preferred embodiment of step (A) of method 1, the at least one halogen-free flame retardant is first dissolved or dissolved in a solution of at least one precursor compound of at least one metal oxide or metalloid oxide. Distributed. Furthermore, preferably at least one nonionic surfactant present optionally is dissolved in water and this aqueous solution is subsequently mixed with the organic solution.

  Generally, the above ingredients for producing the emulsion described in step (A) may be mixed using a simple mixer or stirrer known to those skilled in the art. In a preferred embodiment, step (A) is performed by applying high shear forces to the emulsion to achieve efficient mixing of the components. In a preferred embodiment, the production of the emulsion according to step (A) is carried out under the action of high shear forces or shear rates. The shear rate is preferably 5000 to 10,000 rpm.

  Furthermore, in a preferred embodiment, high pressure homogenization can be performed. The energy exerted on the emulsion by the high pressure causes cavitation, perturbation, shearing and collisions that support the formation of a few different hydromechanical effects, such as nanoscale droplets with a homogeneous distribution be able to.

  Step (A) of the process according to the invention may be carried out by means of a homogenization valve or a grinding cell, for example under the action of optionally high pressure, for example 500 to 2000 bar, preferably 800 to 1500 bar. An example of a high pressure homogenizer is a microfluidizer.

Step (B):
After an emulsion having the desired oil droplet size is formed in the emulsification step (A), it is advantageously adjusted to an appropriate pH value in the treatment step (B), for example addition of an acid or base Introduces hydrolysis and polycondensation of the sol-gel precursor at the oil-water phase boundary.

  Step (B) of method 1 according to the invention comprises the shaping of core-shell type particles, wherein at least one flame retardant is in the core and at least one metal oxide or metalloid oxide is Present in the shell.

  Step (B) can generally be carried out by all methods known to those skilled in the art, and by these methods at least one metal oxide or metalloid oxide used in step (A) At least one precursor compound is converted into the corresponding metal oxide or metalloid oxide.

  In a preferred embodiment of the method according to the invention, the shaping of the core-shell particles in step (B) is carried out by changing the pH value in the emulsion.

  According to the invention, depending on the pH value of the starting emulsion, the pH value may be changed by addition of an acid or a base. In a preferred embodiment, acid is added in step (B) to prepare an emulsion having a pH value of 2-6. In a further embodiment, in step (B) of the process according to the invention, a base is added in order to obtain an emulsion having a pH value of 8-12.

For the adjustment of the pH value in step (B) of method 1 according to the invention, as acids, for example, halogen hydroacids such as hydrochloric acid (HCl), hydrobromic acid (HBr), hydroiodic acid (HI) and These solutions may be used. Further suitable acids are halogen oxygen acids such as hypochlorous acid, chlorous acid, perchloric acid (HClO ₄ ), periodic acid (HIO ₄ ). According to the present invention, sulfuric acid (H ₂ SO ₄ ), fluorosulfuric acid, nitric acid (HNO ₃ ), phosphoric acid (H ₃ PO ₄ ), fluoroantimonic acid, fluoroboric acid, hexafluorophosphoric acid and chromic acid (H ₂ CrO ₄ ) Is also suitable. These acids are preferably used in aqueous solution.

  Preferred bases are, for example, alkali metal hydroxides such as sodium hydroxide or potassium hydroxide, alkaline earth metal hydroxides such as calcium hydroxide or ammonia. Sodium hydroxide, potassium hydroxide or ammonia is particularly preferably used. These bases are preferably used in aqueous solution.

  Thus, in a preferred embodiment, in step (B) of method 1 according to the invention, the emulsion from step (A) is advantageously brought to a constant pH value with at least one aqueous solution of the acid or base described above. Adjusted. This pH value is, for example, 2 to 12, preferably 2 to 6 or 8 to 12. Particularly preferably, the pH value is adjusted to 8-10.

  Step (B) may be generally performed at a temperature of 10 to 80 ° C. Step (B) is in a preferred embodiment carried out for at least 2 hours, for example 2 to 16 hours.

  In a preferred embodiment, no other components are present in the core of the particles produced according to the invention, together with a liquid halogen-free flame retardant. In a particularly preferred embodiment, the concentration of the at least one liquid halogen-free flame retardant is at least 50% by weight, particularly preferably at least 60% by weight, based on the total weight of the core.

  In a preferred embodiment, the core of the particles to be produced according to the invention is a liquid core, particularly preferably the core is a liquid oily core.

  The at least one liquid flame retardant present in the core of the core-shell particles to be produced according to the invention is 50 to 99% by weight, particularly preferably 60 to 90% by weight, based on the total particles, in the particles. Present in quantity. The at least one metal oxide or metalloid oxide present in the shell of the core-shell particle to be produced according to the invention is 1 to 50% by weight, particularly preferably 10 Present in an amount of 40% by weight. In a preferred embodiment, the sum of the amounts of at least one flame retardant and at least one metal oxide or metalloid oxide is 100% by weight.

  Step (B) can be followed by processing steps known to those skilled in the art, such as centrifugation, filtration, evaporation, resuspension in an aqueous medium or dialysis. The treatment step in this case is used to separate the produced core-shell type particles from the liquid component of the emulsion according to the invention.

Step (C):
Step (C) according to the case of method 1 according to the invention comprises the drying of the core-shell particles from step (B).

  Optionally, step (C) according to the invention preferably comprises a proportion of water obtained from step (B) that is too high for further processing, for example the production of polymeric molding materials, or other It is carried out when the organic solvent is included.

  Step (C) may be carried out according to the invention by methods known to those skilled in the art, for example by spray drying.

  According to the invention, the diameter of the particles produced by the method 1 is, for example, 0.1 to 100 μm, preferably 0.2 to 20 μm, particularly preferably 0.5 to 5 μm. The diameter is according to the invention the largest possible distance among the particles produced according to the invention.

  The present invention also relates to method 2 comprising at least steps (D), (E) and (F). These steps are described in detail below.

Step (D):
Step (D) comprises the preparation of a mixture containing water, at least one polar solvent, at least one halogen-free flame retardant and at least one precursor compound of at least one metal oxide or metalloid oxide. .

  In step (D) according to the invention, at least one polar solvent is used. According to the invention, polar solvents known to those skilled in the art may be used. According to the present invention, a polar solvent is one whose dielectric constant exceeds 15.

  In a particularly preferred embodiment of the process according to the invention, the at least one polar solvent in step (D) is at least one alcohol.

  Suitable alcohols are methanol, ethanol, propanol, such as n-propanol, isopropanol, butanol, such as n-butanol, isobutanol, tert-butanol, pentanol, such as n-pentanol, isopentanol, tert-pentanol, It is selected from the group consisting of methyl-pentanol, n-hexanol, dimethyl-butanol, ethyl-butanol, n-heptanol, n-octyl-alcohol, n-nonyl-alcohol, n-decyl-alcohol.

  The at least one polar solvent is generally present in the mixture in an amount of from 10 to 60% by weight, preferably from 20 to 50% by weight, particularly preferably from 30 to 40% by weight, based on the total mixture.

  Further water is present in the mixture prepared in step (D) of method 2 according to the invention. The water is generally present in an amount of 5 to 35% by weight, preferably 10 to 30% by weight, particularly preferably 15 to 25% by weight, based on the total mixture.

  For at least one halogen-free flame retardant and for at least one precursor compound of at least one metal oxide or metalloid oxide, what has been said in connection with step (A) of method 1 is applicable.

  At least one halogen-free flame retardant is generally present in the mixture in an amount of from 5 to 40% by weight, preferably from 10 to 30% by weight, particularly preferably from 15 to 25% by weight, based on the total mixture, respectively. To do.

  At least one precursor compound of at least one metal oxide or metalloid oxide is generally in the mixture, generally 10-60% by weight, preferably 20-50% by weight, particularly preferably in each case based on the total mixture. It is present in an amount of 30-40% by weight.

  The total amount of components present in the mixture described in step (D) of method 2 according to the invention is 100% by weight.

  The mixture produced in step (D) of method 2 according to the present invention may contain a buffer in a preferred embodiment.

Within the scope of the present invention, the buffer is a weak acid and its conjugate base, or a mixture of a weak base and its conjugate acid. The buffer allows the pH value to change only slightly when a small amount of strong acid or base is added. In order to maintain the pH value of the solution almost constant, a buffer is used. Examples of buffers are hydrochloric acid and sodium citrate, citric acid and sodium citrate, acetic acid and sodium acetate, K ₂ HPO ₄ and KH ₂ PO ₄ , Na ₂ HPO ₄ and NaH ₂ PO ₄ , borax and sodium hydroxide, Preference is given to an aqueous solution of borax and sodium hydroxide.

  All components present in the mixture described in step (D) of method 2 according to the invention can be mixed with one another in a manner known to those skilled in the art, for example using a magnetic stirrer.

  In this case, the stirring speed is generally 100 to 600 rpm, preferably 200 to 500 rpm, particularly preferably about 300 rpm. Stir for a sufficiently long time, eg 2-10 minutes.

Step (E):
Step (E) of method 2 according to the present invention comprises at least one metal oxide or semimetal to obtain particles containing at least one metal oxide or metalloid oxide and at least one halogen-free flame retardant. Conversion of at least one metal oxide or metalloid oxide at least one precursor compound into a metal oxide.

  The conversion of at least one metal oxide or metalloid oxide at least one precursor compound into at least one metal oxide or metalloid oxide is known to the person skilled in the art in step (E) of the process according to the invention. This can be done by all methods.

  In a preferred embodiment, step (E) is performed by heating the mixture from step (D). In general, this mixture is heated in this embodiment to a temperature of 30 to 100 ° C., preferably 40 to 80 ° C. Heating can be performed in all reactors known to those skilled in the art, for example, in a stirred hot plate known to those skilled in the art. The heating in step (E) is preferably carried out so that the solvent, ie water and / or polar solvent, can escape.

  A gel is advantageously formed from the liquid mixture by heating in step (E).

  In step (E) of method 2 according to the invention, drying can also be carried out after the formation of the gel. This drying is preferably carried out in order to separate the solvent present, ie water and / or polar solvent, from the particles. In drying in this case, aging of the gel for forming particles is also performed. Drying is generally performed at a temperature of 100 to 200 ° C., for example, in a spray dryer.

  In step (D) of the process according to the invention, in step (E) at least one halogen-free flame retardant and at least one metal oxide or metalloid oxide are formed by forming an essentially homogeneous mixture. Are formed in an essentially uniform distribution.

Step (F):
Step (F) in the case of the method according to the invention comprises the drying of the particles from step (E).

  In a preferred embodiment of the method according to the invention, step (F) is carried out.

  Preferably, in step (F), each sample from step (E) is first spray dried using a small spray dryer B-290 (Buechi, Schweiz) to remove water respectively.

Spray drying is preferably carried out under the following conditions:
For example, an inlet temperature of about 80-150 ° C, preferably 110-130 ° C, such as 120 ° C; for example, an outlet temperature of about 40-65 ° C, preferably 45-60 ° C, such as 55 ° C. Preferably, a two-material flow nozzle is used. Furthermore, the use of nitrogen as the atomizing gas is preferred.

  The particle size of the fine powder obtained in step (F) is, for example, 0.1 to 50 μm, preferably 0.5 to 20 μm, particularly preferably 1 to 5 μm.

The present invention also provides at least one halogen-free flame retardant and a metal oxide or semi-metal oxide selected from the group consisting of SiO ₂ , TiO ₂ , ZnO, ZrO ₂ , Al ₂ O ₃ and mixtures thereof. It relates to the contained particles.

With regard to the halogen-free flame retardants and the metal oxides or metalloid oxides described, what has been said in connection with the methods 1 and 2 according to the invention applies. In a particularly preferred embodiment, at least one metal oxide or semimetal oxide is SiO _2. The at least one halogen-free flame retardant is particularly preferably triphenylphosphine, diphenyl (o-toluyl) phosphine, tributylphosphine oxide, trioctylphosphine oxide, diphenylphosphite, triphenylphosphite, tris (nonylphenyl). Phosphite, dimethylmethylphosphonate, dioctylphenylphosphonate, triphenylphosphate, tritoluylphosphate, resorcinol-bis (diphenylphosphate), bisphenol A-bis (diphenyl) phosphate, poly (m-phenylenemethyl) phosphonate (formula (VIII)) And a mixture thereof.

  In a preferred embodiment, the present application also relates to particles according to the invention, in which the particles have at least one halogen-free flame retardant in the core and at least one metal oxide or metalloid oxide. It is a core-shell type particle present in the shell. In this embodiment, the amount of at least one halogen-free flame retardant in the particles is preferably greater than 50% by weight, particularly preferably greater than 70% by weight, based on the total particle respectively.

  The ratio of the average thickness of the shell to the average diameter of the capsules is preferably 1:20 to 1: 200, particularly preferably 1:50 to 1: 100.

  Still further, in a preferred embodiment, the invention relates to a particle according to the invention, in which the at least one halogen-free flame retardant and the at least one metal oxide or metalloid oxide have an essentially uniform distribution. It is contained in. In this embodiment, the amount of at least one halogen-free flame retardant in the particles is preferably above 70% by weight, respectively, based on the total particle.

  The particles produced according to the invention have the advantage that they can be incorporated into polymer molding materials more easily in terms of processing technology than is possible with liquid flame retardants. By using the particles according to the invention, it is possible to avoid sticking of molds used, for example, in the production of molding materials. Another advantage is that when the particles according to the invention are used in a polymer molding material, the undesirable plasticizing effect of the flame retardant can be avoided. This is because the particles are not used in a liquid form, but in a form combined with a metal oxide or metalloid oxide. Furthermore, the flame retardant used in the form according to the invention exhibits a better flame retardant action than when used in a free form. Furthermore, according to the present invention, separation / leaching out of the polymer molding material due to dissolution of the flame retardant can be avoided, which can occur when a liquid flame retardant is used. .

  The invention also relates to a polymer molding material containing particles according to the invention and at least one thermoplastic polymer or thermosetting polymer.

  According to the invention, the polymer molding material contains, for example, polyesters such as poly (ethylene-terephthalate), poly (butylene-terephthalate), poly (trimethylene-terephthalate), poly (cyclohexene-dimethylene-terephthalate), or alkyl diene. Acids such as polyester from adipic acid, polyamides such as polyamide 6, polyamide 6.6 or another polyamide type, polyolefins such as polyethylene, polypropylene, poly (vinyl chloride), poly (vinyl acetate), poly (vinyl alcohol), Poly (methyl methacrylate), polyacrylate, polystyrene, poly (acrylonitrile-butadiene-styrene), polyurethane, polycarbonate, epoxy resin, and optionally cross-linked unsaturated polymers. Selected from esters and the group consisting of mixtures or blends of these polymers can be any polymer known to those skilled in the art exists.

  In the polymer molding material according to the invention, the particles according to the invention are generally present in an amount of 1 to 50% by weight, preferably 1 to 30% by weight, based on the total polymer molding material, respectively.

  In the polymer molding material according to the invention, there are optionally present nitrogen-containing synergists such as melamine, melam, melem, melamine cyanurate, melamine polyphosphate, ammonium phosphate, ammonium pyrophosphate, ammonium polyphosphate and mixtures thereof. Good. This nitrogen-containing synergist is preferably present in an amount of 0 to 50% by weight, preferably 1 to 50% by weight, particularly preferably 1 to 30% by weight, in each case based on the total polymer molding material.

  In the polymer molding material according to the invention, there may optionally be present anti-drip reagents and other synergists such as poly (tetrafluoroethylene), zinc oxide, zinc borate, silica, silicates, epoxides and mixtures thereof. . This additive is preferably present in an amount of 0 to 10% by weight, preferably 0.2 to 10% by weight, particularly preferably 0.2 to 4% by weight, in each case based on all polymer molding materials.

  In the polymer molding material according to the invention, other halogen-free flame retardants may optionally be present. The amount of other halogen-free flame retardant present in this case is, for example, 0 to 30% by weight, preferably 0 to 20% by weight. This flame retardant is, for example, a metal phosphinate salt or a metal hydroxide.

  In the polymer molding material according to the invention, optionally other polymer additives may be present, for example for improving flame retardancy, mechanical properties, electrical properties, chemical properties and hydrolysis properties. Such polymers include, for example, epoxy polymers, polyacrylates, rubbers, silicones, maleic anhydride, modified polymers, and the like. This additive is preferably present in an amount of 0 to 50% by weight, preferably 1 to 50% by weight, particularly preferably 5 to 20% by weight, in each case based on all polymer molding materials.

  In some cases, glass fibers may be present in the polymer molding material according to the invention. The glass fibers are preferably present in an amount of 0 to 80% by weight, preferably 15 to 30% by weight, based on each polymer molding material.

  Other optional additives are those selected from the group consisting of lubricant additives, nucleophiles, stabilizers, transverse crosslinkers and the like.

  The invention also relates to a method for producing the polymer molding material according to the invention by mixing the particles with at least one thermoplastic polymer or thermosetting polymer.

  If a thermoplastic polymer is used, the mixing can generally be performed by all methods known to those skilled in the art, for example by mixing in a melt. Mixers, kneaders, extruders and blenders known to those skilled in the art, preferably extruders, may be used. Single or twin screw extruders with various diameters and volumes may be used. The individual components are preferably mixed with one another in the molten state. Subsequently, the resulting thermoplastic molding material can be converted into a granulate, for example, by cutting. From this granulate, according to the present invention, a molded member can be produced, for example, by injection molding. This method is known to those skilled in the art.

  When using thermosetting polymers such as epoxy resins or optionally cross-linked, unsaturated polyesters, the components may be reacted with each other in standard methods including mixing and curing, or in other known methods. . The methods described are known to those skilled in the art.

  The invention also relates to the use of the particles according to the invention in polymer molding materials.

  The invention also relates to the use of the particles according to the invention for imparting flame retardancy to polymer molding materials.

  With respect to the use according to the invention, what has been said in connection with the particles according to the invention and with respect to the molding material according to the invention applies.

Example:
In the examples, the following abbreviations are used:
TEOS tetraethoxysilane,
PTES phenyltriethoxysilane,
RDP bis (diphenyl phosphate),
PMP poly (m-phenylene-methylphosphonate),
PC polycarbonate,
SAN polystyrene acrylonitrile containing 76% by weight styrene and 24% by weight acrylonitrile,
Poly (acrylonitrile-butadiene-styrene) containing 38% by weight of ABS styrene, 12% by weight of acrylonitrile and 50% by weight of butadiene,
PTFE poly (tetrafluoroethylene),
Ultradur B4300 G6 Poly (butylene terephthalate) resin containing 30% by weight glass fiber. This resin has a viscosity number of 130 ml / g, measured as a 0.5% by weight solution in phenol / o-dichlorobenzene, 1: 1 mixture.
MC Melamine cyanurate

  As silica, Aerosol 8200 is used.

Example 1: Encapsulation of RDP in a core-shell structure 12 g of RDP is dissolved in 12 g of TEOS solution at room temperature. 0.6 g Tween 80 is dissolved in 144 g water. The oil phase is homogenized in the aqueous phase for 1 minute at a pressure of 500 bar using a high-pressure homogenizer (M-1 10F microfluidizer, microfluidics). The completed emulsion is transferred into a 1 liter beaker equipped with a magnetic stirrer (300 rpm). Citric acid-caustic soda solution-sodium chloride buffer 8 g (pH 4) is added as a catalyst, and the emulsion is stirred for 10 hours. This suspension is dried using a spray dryer to obtain fine particles.

  The particle size distribution is measured with Bluewave (Microtrack S3500 Bluewave, Microtrack), resulting in D50 = 0.5 μm, D90 = 1.0 μm.

  To remove residual moisture and surfactant, the product is calcined in vacuo at 280 ° C. for 20 minutes. The final product is used as compound A in the following examples. After calcination, Compound A contains 7.9% by weight phosphorus, suggesting an RDP loading of 73% by weight.

Example 2: Encapsulation of RDP in a core-shell structure 12 g of RDP are dissolved in 9 g of TEOS solution and 3 g of PTES solution at room temperature. 0.6 g Tween 80 is dissolved in 144 g water. The oil phase is homogenized in the aqueous phase for 1 minute at a pressure of 500 bar using a high-pressure homogenizer (M-1 10F microfluidizer, microfluidics). The completed emulsion is transferred into a 1 liter beaker equipped with a magnetic stirrer (300 rpm). Citric acid-caustic soda solution-sodium chloride buffer 8 g (pH 4) is added as a catalyst, and the emulsion is stirred for 16 hours. This suspension is dried using a spray dryer to obtain fine particles.

  The particle size distribution is measured with Bluewave (Microtrack S3500 Bluewave, Microtrack), resulting in D50 = 0.6 μm, D90 = 1.2 μm.

Example 3: Encapsulation of RDP in matrix structure 20 g RDP is dissolved in 30 g TEOS solution and 10 g PTES solution at room temperature. This mixture is dissolved in 20 g of ethanol. This oil phase is added to 20 g (pH 4) of citric acid-caustic soda solution-sodium chloride buffer. The solution is stirred for 2 minutes with a magnetic stirrer (300 rpm). The solution is transferred into a stirring hot plate at a temperature of 40 ° C. for 10 hours. This suspension is dried using a spray dryer to obtain a fine powder. The particle size distribution is measured with Bluewave (Microtrack S2500 Bluewave, Microtrack), resulting in D50 = 1.0 μm, D90 = 1.6 μm.

Example 4: Encapsulation of PMP in matrix structure 13 g of PMP are dissolved in 10 g of TEOS solution and 3 g of PTES solution at 60 ° C. This mixture is immediately added into ethanol. 60 g of citric acid-caustic soda-sodium chloride buffer (pH 4) is heated to 60 ° C. The oil phase is mixed with the aqueous phase at 60 ° C. and the mixture is stirred for 2 minutes. The solution is transferred into a stirring hot plate at a temperature of 80 ° C. for 10 hours. This suspension is dried using a spray dryer to obtain a fine powder. The particle size distribution is measured with Bluewave (Microtrack S3500 Bluewave, Microtrack), resulting in D50 = 1.5 μm, D90 = 2.5 μm.

  To remove residual moisture and surfactant, the product is calcined in vacuo at 280 ° C. for 20 minutes. The final product is used as compound B in the following examples. After calcination, compound B contains 12.9% by weight phosphorus, suggesting that the loading with PMP is 72% by weight.

Example 5: Use of RDP in FR PC / ABS (comparison)
The FR PC / ABS composition is shown in Table 1. The material is mixed in a 17 ml small extruder at 280 ° C. for 3 minutes at a screw speed of 80 rpm and then injected by injection molding into an injection mold at a pressure of 15 bar, UL94 having 1.6 mm Manufacture rods. The manufactured rods were tested according to UL94-conditions (two consecutive 10 seconds of ignition) and self-extinguished without dripping, thus meeting the V0 requirement. During mixing, the RDP remains stuck to the feeder device and metering is difficult. The specimen has a low heat deflection temperature of 85 ° C., which is based on the RDP plasticizing effect.

Example 6: Use of encapsulated RDP (compound A) having a core-shell structure in FR PC / ABS Compound A is prepared as described in Example 1. The composition of FR PC / ABS is shown in Table 1. The material is processed and tested in the same manner as in Example 5. Compound A is used in powder form and can be easily metered. The manufactured rod is self-extinguishing without dripping and meets the V0 classification. The specimen has a heat deflection temperature of 92 ° C., which indicates that encapsulated RDP can reduce the plasticizing effect of liquid RDP.

Example 7: Use of PMP in FR PBT (comparison)
The composition of FR PBT is shown in Table 2. The material was mixed in a 17 ml small extruder at a temperature of 260 ° C. for 3 minutes at a screw speed of 80 rpm, then injected by injection molding at a pressure of 15 bar into the injection mold part, 1.6 mm Change to a UL94 rod with During mixing, the PMP sticks to the feeder device and tends to be difficult to meter and supply. During the melt injection, the filling rate in the mold is 60%. The manufactured rods were tested according to the description of UL 94 and burned completely, which corresponds to the UL 94 classification of V--. The glass transition temperature of the composite is 27 ° C. based on the plasticizing effect of PMP, which is clearly lower than standard PBT (40 ° C.).

Example 8: Use of PMP in FR PBT (comparison)
The composition of FR PBT with the same loading of PMP and silica as in Example 9 is shown in Table 2. The material is processed and tested in the same manner as described in Example 7. During mixing, the PMP sticks to the feeder device and tends to be difficult to meter and supply. During melt injection, the mold is filled 50%, which is less than in Example 7, indicating that the presence of silica increases the melt viscosity of the polymer. The manufactured rod is tested according to the description of UL 94 and is in a state of self-extinguishing without dripping, which corresponds to a classification of V0. The glass transition temperature of the composite is 30 ° C.

Example 9: Use of Encapsulated PMP (Compound B) with Matrix Structure in FR PBT Compound B is prepared as described in Example 5. The composition of FR PBT is shown in Table 2. The material is processed and tested in the same manner as described in Example 7. Compound B has the form of a powder and can be easily metered. The mold is 60% filled as described in Example 7, which is higher than in Example 8, indicating that the encapsulated PMP does not change the melt viscosity. The manufactured rod was tested according to the description of UL 94 and is in a state of self-extinguishing without dripping, which meets the classification of V0 and is much better than in Example 7. Encapsulated PMP is a better flame retardant than liquid PMP. The glass transition temperature of the composite is 36 ° C., which is higher than in Examples 7 and 8. This is because encapsulation of PMP reduces the plasticizing effect of the composite.

Claims (14)

A method for producing particles containing at least one halogen-free flame retardant and at least one metal oxide or metalloid oxide, comprising at least the following steps:
(A) producing an aqueous emulsion containing at least one flame retardant and at least one precursor compound of at least one metal oxide or metalloid oxide;
(B) forming core-shell type particles, wherein at least one flame retardant is present in the core of the particle and at least one metal oxide or metalloid oxide is present in the shell of the particle And (C) optionally drying the core-shell particles from step (B),
Or (D) producing a mixture containing water, at least one polar solvent, at least one halogen-free flame retardant and at least one precursor compound of at least one metal oxide or metalloid oxide,
(E) converting at least one precursor compound of at least one metal oxide or metalloid oxide into at least one metal oxide or metalloid oxide, at least one metal oxide or metalloid oxide and at least The above process comprising the steps of obtaining particles containing one halogen-free flame retardant and (F) optionally drying the particles from step (E). At least one halogen-free flame retardant is triphenylphosphine, diphenyl (o-toluyl) phosphine, tributylphosphine oxide, trioctylphosphine oxide, diphenylphosphite, triphenylphosphite, tris (nonylphenyl) phosphite, dimethyl Is selected from the group consisting of methyl phosphonate, dioctyl phenyl phosphonate, triphenyl phosphate, tritoluyl phosphate and mixtures thereof;
2. The method of claim 1, wherein the process is selected from the group consisting of resorcinol-bis (diphenyl phosphate), bisphenol A-bis (diphenyl phosphate), poly (m-phenylene methyl phosphonate) and mixtures thereof. At least one metal oxide or semi-metal oxide _is one selected from the group consisting of _{SiO 2, TiO 2, ZnO,} ZrO 2, Al 2 O 3 and mixtures thereof, The method of claim 1 or 2, wherein . As precursor compounds for SiO ₂ , the general formula (IX)

Wherein R ²⁷ , R ²⁸ , R ²⁹ and R ³⁰ independently of one another represent hydrogen, an alkyl group, an aryl group, an alkyloxy group and / or an aryloxy group, The method of claim 3.   The method according to any one of claims 1 to 4, wherein the formation of the core-shell type particles in the step (B) is carried out by changing the pH value of the emulsion.   6. A process according to any one of claims 1 to 5, wherein the at least one polar solvent in step (D) is at least one alcohol. Containing at least one halogen-free flame retardant and at least one metal oxide or metalloid oxide selected from the group consisting of SiO ₂ , TiO ₂ , ZnO, ZrO ₂ , Al ₂ O ₃ and mixtures thereof particle.   8. Particles according to claim 7, wherein the particles are core-shell particles in which at least one halogen-free flame retardant is present in the core and at least one metal oxide or metalloid oxide is present in the shell.   8. Particles according to claim 7, comprising at least one halogen-free flame retardant and at least one metal oxide or metalloid oxide in an essentially uniform distribution.   9. Particles according to claim 7 or 8, wherein the concentration of the core material with respect to the total mass of the particles exceeds 50% by weight.   A polymer molding material comprising the particles according to claim 7 and at least one thermoplastic polymer or thermosetting polymer.   12. A method for producing a polymer molding material according to claim 11, wherein said polymer molding material is produced by mixing said particles with at least one thermoplastic polymer or thermosetting polymer. Way for.   Use of particles according to any one of claims 7 to 10 in polymer molding materials.   Use of the particles according to any one of claims 7 to 10 for imparting flame retardancy to a polymer molding material.