DE202010013850U1 - Polymer foam body or particulate expandable polymer particles - Google Patents

Abstract

Polymer foam body or expandable polymers for further processing into a polymer foam body, in particular particulate expandable polymer particles containing carbon-containing athermane particles, characterized in that the carbon of the athermanous particles is present both partially graphitic ordered and turbostratic.

Description

The The invention relates to polymer foam bodies or expandable Polymerizatel according to the preamble of the claim 1.

foamed Insulating materials produced from expandable polymers, for example, from expandable styrene polymer particles (EPS), or polymer extruded foams, for example styrene polymer extruded foams (XPS) are known in the art.

at The expandable polymers are usually propellant-containing Polymer particles, e.g. As polystyrene or Cellulosacetatbutyrat, by heating with steam in a Vorschäumprozess expand under multiplication of their volume and then by welding to arbitrarily shaped moldings, in particular to plates or blocks, can be processed.

Several processes are known for the preparation of expandable polymers. By suspension polymerization z. B. expandable polystyrene be prepared by polymerization of styrene and gassing with a blowing agent. Furthermore, expandable or expanded polymers can mechanically by extrusion of polymer melts and mixing a blowing agent in the polymer melt and subsequent promotion through a nozzle plate to extruded granules, eg. B. EPS granules, processed, or by foaming directly after a nozzle to foamed plates (XPS plates) are processed. Furthermore, processes are known in which expandable styrene polymers are produced by means of static mixing elements, for example according to EP 0 668 139 (SULZER CHEMTECH AG).

preferred Areas of application of such polymer foams are, mostly plate-shaped, Thermal insulation materials such as EPS, z. B. for building facades, Cold stores or packaging materials, where the thermal insulation effect of the foam of decisive Importance for its quality.

For reasons of saving material, it is generally desired to produce materials, in particular thermal insulation boards, with the lowest possible density of about 15 kg / m ³ . At the same time, however, these plates should also have the lowest possible thermal conductivity. However, it should be noted that, for example, EPS thermal insulation panels achieve a minimum thermal conductivity at a density of about 30 kg / m ³ and a further reduction in the density of the material leads to an increase in the thermal conductivity. Other polymer foams show a comparable behavior.

In this context, known from the prior art, the "classic" white particle foams without infrared opacifiers, z. B. Styrofoam ^® . Although these are relatively inexpensive to manufacture, they do not reach the lowest heat conduction groups. For example, at a density of 15 kg / m ^3, EPS only reaches the heat transfer group WLG 040 at best DIN 18164 ,

In order to reduce this disadvantage, an attempt was made to lower the thermal conductivity by adding infrared opacifiers. Here are known from the prior art gray or black particle foams containing infrared opacifiers such as graphite, for example Lambdapor ^® or Neopor ^® . These show a significantly improved thermal insulation and reach at the same density of 15 kg / m ³ the lowest heat transfer group WLG 032 according to DIN 18164 ,

Also from the prior art, for example from the WO 2004 065468 (MURJAHN AMPHIBOLIN WERKE), thermal insulation panels are known, which are obtained by a mixture of the above particles in approximately equal parts and are referred to as "Dalmatinerplatten". These thermal insulation panels made of EPS reach the heat conductivity group WLG 035 according to a density of 15 kg / m ³ DIN 18164 Thus, as expected, the thermal insulation is in the range between the above-mentioned white and black products.

to Reduction of thermal conductivity could you also increase the density of the insulation boards. This would be but with disadvantages, in particular with increased material costs, etc. connected and should therefore also be avoided.

Also The content of infrared opacifiers can not be arbitrary be increased, thereby increasing the insulating effect, on the one hand, this makes the final product more expensive and, on the other hand, negative Effects on the stability of the foam or on the Manufacturing process would have.

In the EP 620 246 (ALGOSTAT GMBH & CO KG), for example, the use of atherman materials in polystyrene foams is proposed. The athermanous materials should also absorb or reflect infrared rays. As athermane materials metal oxide, non-metal oxide, metal powder, aluminum powder, carbon or organic dye, in particular in the form of pigments or mixtures of these materials are proposed.

According to the WO 00 43442 (SUNPOR KUNSTSTOFF GES MBH) proposes to use aluminum particles to improve thermal insulation properties. Although aluminum particles can insulate infrared radiation, there is a risk of dust explosions in the case of the proposed particle sizes between 1 and 15 μm.

In the WO 97 45477 (BASF AG) is proposed to incorporate soot particles in expanded styrene polymers. As a result, the thermal insulation should be significantly improved. The decisive disadvantage in the use of carbon black on the one hand is the high specific surface area of the carbon black particles. As a rule, soot particles are above 100 m ² / g according to BET. Such high surface areas absorb the additionally required flame retardants and worsen the rheological behavior during processing. Furthermore, the soot particles absorb the incoming heat radiation strongly, resulting in the application of thermal insulation boards on facades during processing, due to the sunlight, to a strong warming of the thermal insulation panels and to processing defects, eg. As cracks or thermal stresses can result.

After the apprenticeship of WO 98 51734 (BASF AG) graphite particles are introduced into expandable styrene polymers. The graphite used here has a preferred average particle size of 1-50 microns, in particular of 2.5-12 microns, a bulk density of 100-500 kg / m ³ and a specific surface area of 5-20 m ² / g. Natural graphite or ground synthetic graphite is proposed. It should thus be achieved with a polystyrene foam of density 10 kg / m ^3, a reduction in the thermal conductivity of 44 [mW / (m · K)] to less than 35 [mW / (m · K)]. Disadvantage of the use of graphite is that through the use of graphite, although a certain reduction in thermal conductivity compared to graphite insulation materials is achieved, but due to the good intrinsic heat conduction of graphite, a concentration limit is reached, in the further reduction of the attenuation of the heat radiation passing through Graphite, which is more than offset by the high thermal conductivity of the graphite. The thermal conductivity can therefore not be lowered further from a concentration dependent on the density of the foam body, not even by increased additions of graphite. An EPS foam body with a content of 4 wt .-% coarse crystalline natural graphite shows at a density of 30 kg / m ^3, a thermal conductivity of 30.0 mW / (m · K). A graphite content of 12 wt .-% already increases the thermal conductivity to 30.9 mW / (m · K) at the same density.

In the WO 2010 031537 (HC CARBON GMBH) it is proposed to use petroleum coke or calcined petroleum coke as an additive for reducing the thermal conductivity. The described calcined petroleum coke has a purity of 99% carbon, is not of graphitic structure and has no displaceable layers, so it has a two-dimensional long-range order of the carbon atoms in planar hexagonal networks, but no crystallographic order in the third dimension. Petroleum cokes vary considerably in their nature, especially in porosity, and often contain significant levels of impurities. Another disadvantage of petroleum coke is that the production of platelet-shaped particles is expensive.

Graphite, most commonly used as an infrared opacifier, is an allotropic form of the element carbon and consists of layers of hexagonally arranged carbon atoms in a planar condensed ring system (graphene). The layers are stacked parallel to each other in crystallographic three-dimensional long-range order (graphene layers or graphene layers). The chemical bonds within the layers are covalent with sp ² hybridization and with a CC distance of 141.7 pm. The weak bonds between the layers are metallic and of a strength comparable only to the van der Waals bond. For graphite, the distance between two graphene layers is 335.4 pm (about twice the van der Waals radius). These bonds are more than twice as long as the bonds within a layer. This makes them very weak, and many properties of graphite, eg. As the electrical and thermal conductivity, the mechanical properties, etc., show a tensorielle dependency.

An advantage of using graphite is that graphite can be well delaminated along these weakly bonded layers, thus easily and inexpensively obtaining high aspect ratio platelet-shaped crystalline particles having high reflectivity to infrared rays. This is advantageous because of a high aspect ratio, coupled with a small absolute particle size, without the existence of layers along which a delamination can take place, are difficult to produce.

you distinguishes two modifications or two allotropic forms different stack arrangement: The hexagonal (α-graphite) and the rhombohedral (β-graphite). β-graphite finds often in natural graphites and can through Heat action (above 1025 ° C) in the thermodynamic more stable hexagonal shape to be converted. The reverse transformation succeeds by grinding.

In The following is used under the terms "graphitic" and "graphitic Structure "," Graphite Shares "or" Graphite Shares " Areas "understood that at least parts of a Athermanen particle a layered ordered layered graphite structure from graphene layers with crystalline three-dimensional near and distant order exhibit. This is for example hexagonal or rhombic Graphite, semi-graphite, meta-anthracite, anthracite and high-temperature treated Coke the case.

Next The two ideal forms of the graphitic structure exist in the Reality a bunch of carbon solids, although within the individual Graphenlagen a perfect arrangement have the carbon atoms but one due to packing errors increased layer spacing of greater than 344 pm show (turbostratic crystal structure).

In 1 the different structures are shown.

Under The term "turbostratic" is used below Areas of Athermanous Particles with Spatial Suborder and deviations of the interatomic distances and / or angles of attachment in terms of the graphite lattice, but without crystalline long-range order Understood. These areas consist of turbostratic groups, each group consisting of a number of stacked graphite layers exists that are parallel and equidistant to each other, but each layer is a completely random orientation to the normal layer has. The turbostratic structure is z. B. in carbon blacks, coal, coke or petroleum coke and has no crystalline order between the layers. In turbostatic Structure there are many defects that lead to larger ones Distances and a deviation from the ideal hexagonal Lead structure.

Under the terms "non-graphitic" or "non-graphitic" Structure "or" non-graphic areas " in the following, areas of athermanous particles without crystalline Remote order understood.

For the use of athermanous particles in plastic foams this means in summary that graphite, soot and petroleum coke Although certain advantages, but also serious disadvantages.

graphite particles are almost completely crystalline and show stratified ordered structure. Because of the good cleavability and grindability of graphite are platelet-shaped graphite particles Although correspondingly simple and inexpensive to manufacture and also have good reflective properties, disadvantageous is, however, the mentioned non-limitable limit for the thermal conductivity of graphite by its high intrinsic conductivity and only finite availability of natural graphite deposits.

Carbon black is an agglomerate of spherical primary particles. These primary particles agglomerate into chains or grapes. These agglomerates in turn can form flocs. The primary particles may have diameters of 5-500 nm and consist of a disordered core around which concentric graphite layers (sp ² -hybridized carbon atoms) are arranged. The order of the layers increases towards the outside where turbostratic layer arrangements are present. Soot particles do not have a layered crystalline ordered structure. Accordingly, the production of particles having useful reflection properties is difficult. Although soot particles have a lower intrinsic conductivity than graphite, the particles have predominantly IR-absorbing, but hardly reflective properties and this leads to the adverse heating of the plates in sunlight.

particle petroleum coke not subjected to a graphitizing process, are also turbostratic and have no layers that are slightly displaced against each other, which are advantageous for the easy cleavage to platy Particles of graphitic structures are.

The object of the invention is thus to provide a polymer foam body or expandable polymers containing carbonaceous or predominantly carbon atoms consisting of athermane particles, in which the advantages of graphitic structures are combined while avoiding its essential disadvantages. In particular, the particles should be easy to manufacture, a good Reflexionvermö have in the infrared radiation range and at the same time should not be limited by a too good intrinsic thermal conductivity.

These Task could now solved according to the invention be used that very special athermane particles. These athermanous particles are characterized by the fact that the carbon in the athermanous particles both at least partially graphitic ordered and turbostratic present.

These Solids can with lower energy and Time expenditure to particles with a favorable aspect ratio be processed and cause a significant reduction in the Thermal conductivity in thermal insulation panels.

Solid, consisting mainly of carbon atoms, are based on characterized the layer spacings of their Graphenlagen.

The ideal graphitic arrangement near the ideal slice distance of 335.4 pm show the naturally occurring and synthetic Grafite. In the ideal graphically ordered areas are the layers parallel to each other in crystallographic three-dimensional long-range order Stacked, are easily against each other and the reason for better cleavability in high aspect ratio particles, that is with a great length opposite their height ("plate-shaped" design).

Naturally occurring carbon bodies become with increasing layer distance referred to as semi-graphites, meta-anthracites and anthracites and make transitional states of the natural Graphitization process. They possess both areas in which the layers parallel to each other in crystallographic three-dimensional Long distance order with average slice distances between 340 pm and the ideal graphite layer spacing when stacked also turbostratische areas in variable ratio. With the help of long-lasting high-temperature treatment, at temperatures up to 3000 K and in the absence of oxygen, can also be artificial an increasing crystalline order can be achieved. This tempering process is called graphitization.

Generally Layer spacings greater than 340 pm referred to as turbostratic. These include z. B. Brown and hard coal.

These Classification can also be used for synthetically produced solids, consisting predominantly of carbon atoms, taken over become.

coke can be considered non-graphitic solid, with a high Proportion of the element carbon, structurally in the state of a carbon before the beginning of graphitization, by pyrolysis of organic Material that was partly a liquid or liquid-crystalline state during the Coking process has undergone, with a layer spacing of the Graphene layers greater than 340 pm. By Graphitization can be made from coke synthetic graphite, as well the transitional states to complete graphitized order.

The slice distances can be determined by small-angle X-ray scattering SAXS (small-angle X-ray scattering, wavelength λ = 0.1542 nm, CuKα with a rotating anode (Nanostar, Bruker AXS), equipped with 2D detectors (Vantec 2000 and Image Plate) to cover a size range of 0.1 to 100 nm (small angle X-ray scattering as well as diffraction)). By applying the Bragg equation, the scattering intensity is obtained as a function of the scattering vector q of the d ₀₀₂ reflection, the relation to the scattering angle 2Θ being given by q = 4π / λ sin (Θ). The size of the structure in real space can be obtained directly from d = 2 π / q (d = distance of the planes, λ = wavelength of the radiation, Θ = entrance angle).

The scattering intensity of the scattering vector q of the d ₀₀₂ reflection shows a curve of the approximately Gaussian normal distribution with a peak maximum corresponding to the mean layer spacing in real space for samples with homogeneous layer spacings. From the variance of the normal distribution can be deduced the distribution of the layer distances. Samples composed of regions having different layer spacings can be approximated by superimposing Gaussian functions with peak maxima corresponding to the average layer distances of the different regions. With increasing inhomogeneity of the samples and the layer spacings, the accuracy of the approximation decreases rapidly.

in the The following is the invention with reference to diagrams, for example explained in more detail.

It Diagram 1 shows an example of a graphitic structure Diagram 2 an example of turbostratic structure, diagram 3 is an example of naturally occurring invention Structure with turbostratic and graphitic areas, diagram 4 shows an example of synthetic invention Structure with turbostratic and graphitic areas, the diagrams 5a and 5b Examples of naturally occurring Inventive structure with turbostratic and graphitic areas with overlapping peak maxima and diagram 6 shows the application of a Gaussian normal function.

Thus, the scattering intensity of the scattering vector in high-purity natural graphite shows a very narrow peak at 18.7 nm ^-1 (corresponding to 335.4 pm), see diagram 1.

In non-grafted petroleum coke, the scattering intensity of the scattering vector shows a very broad distribution with a maximum at 18.1 nm ^-1 (corresponding to 347 pm), see diagram 2.

Anthracite is a naturally occurring example of a structure according to the invention having graphitized and turbostratic regions, see Chart 3. It has a very narrow peak at 18.7 nm ^-1 (corresponding to 335.4 pm) and a broad range with turbostratic layer arrangements, in part superimposed by signals of mineral contaminants.

Carbon body with graphitic and turbostratic areas also be prepared synthetically: By high-temperature treatment of cokes, petroleum cokes, pitch cokes and coal, at temperatures above 1600 K and excluding oxygen, can also be artificial an increasing crystalline, graphite order can be achieved see diagram 4.

Meta-anthracite is a natural example of one inventive structure with ideal graphitic Areas, graphitic areas with not yet complete ideal layer arrangement and turbostratischer areas with wider Distribution, see diagrams 5a and 5b.

The degree of graphitization of the samples was determined by integration of the determined q-curves: The proportion of the graphitic and turbostratic regions was defined as the proportion of the integrated area under the q-curve in the range of 15.0 to 21.0 nm ^-1 . In each case, the peaks generated by the graphitic regions were fit by a Gaussian normal function. This Gaussian curve was subtracted from the original q-curve so as to integrate the area of the turbostratic regions.

Diagram 6 shows an example of this procedure. The evaluation of the areas under the curves showed: Area [] Area% turbostratically 5755 95.6% by integration of the gray curve grafitisch 263 4.4% by integration of the dotted curve

The Percentages of graphite areas in the cited Application and comparative examples were in equivalent Determined way.

The scatter intensity in the diagrams 1 to 6, the x-ray scattering intensity as a function of the scattering vector at the maximum d ₀₀₂ peak was normalized to 100 (au = arbitrary unit values).

Not Accordingly, particles are to be subsumed under the invention of pure graphite with a proportion of ordered layer areas of 100% by weight. Also not to subsume under the invention are particles of soot or petroleum cokes, without graphitic Areas. Even small amounts, about 0.5%, determined by the described above, to facilitate ordered layer areas the production of athermanous particles with a high aspect ratio but considerably.

It Thus, it has surprisingly been found that the use of the particles according to the invention in moldings from polymer foams, their thermal insulation surprising improved, compared with moldings made of polymer foams same density, the additives in the same concentration in the form of pure graphite or carbon black. So can by the decreased intrinsic thermal conductivity of the Particles according to the invention, the use of Graphite particles given limit of thermal conductivity be fallen below.

Like graphite, the platelet-shaped particles have very good reflective properties, so no big e IR absorption and thus no excessive heating of the foamed dam plates, as is the case with the use of soot.

Furthermore is due to the existing graphitic structures and the so good cleavability and millability associated with the production the platelet-shaped particles energy and time-saving possible.

For the use of solids as a damping agent suitable for heat transfer in the infrared range especially isotropic solid consisting predominantly carbon atoms with graphitic and turbostratic regions, such as Semi-graphite, meta-anthracite, anthracite and partially graphitized Cokes and coals. Platelet-shaped particles with a high aspect ratio are particularly preferred. These may be preferred in delaminating mills (eg ball mills or air jet mills).

The Athermanous particles are preferably in the form of solids before, consisting of more than 70 wt .-% of carbon atoms.

there each of these athermanous particles has the invention Structure with graphitic and turbostratic areas. It lies thus not a dry mixture of a first solid or from first atherman particles with exclusively graphitic particles Areas with a second different solid or second different athermanous particles with exclusively turbostatic areas.

The preferred particle size d ₅₀ is in the range between 1 and 50 μm, preferably between 1 and 30 μm, in particular 1 to 10 μm.

The preferred amounts are between 0.1 and 20 wt .-%, preferably between 0.5 and 10 wt .-%, each based on the polymer weight.

The Athermanous particles are advantageously homogeneous in the polymer and uniformly distributed.

To the expandable polymers according to the invention include all thermoplastic, expandable thermoplastics, such as Polystyrene, cellulose acetobutyrate, polyethylene, polypropylene, Polyethylene terephthalate, polylactic acid, and mixtures various thermoplastics.

The expandable polymers according to the invention are preferably expandable styrene polymers (EPS) or expandable Styrene polymer granules (EPS), which in particular of homo- and Copolymers of styrene, preferably glass clear polystyrene (GPPS), Impact Polystyrene (HIPS), anionically polymerized polystyrene or impact polystyrene (A-IPS), styrene-alpha-methylstyrene copolymers, Acrylonitrile-butadiene-styrene polymers (ABS), styrene-acrylonitrile (SAN) acrylonitrile-styrene-acrylic ester (ASA), methyl acrylate-butadiene-styrene (MBS), methyl methacrylate-acrylonitrile-butadiene-styrene (MABS) polymers or mixtures thereof or with polyphenylene ether (PPE). Especially for polystyrene is the need for high quality Products particularly high.

The Styrene polymers mentioned can be used to improve the mechanical Properties or temperature resistance, if necessary using compatibilizers with thermoplastic Polymers such as polyamides (PA), polyolefins such as polypropylene (PP) or polyethylene (PE), polyacrylates, such as polymethylmethacrylate (PMMA), polycarbonate (PC), polyesters, such as polyethylene terephthalate (PET) or polybutylene terephthalate (PBT), polyether sulfones (PES), polyether ketones or polyether sulfides (PES) or mixtures thereof, as a rule in proportions of a total of up to a maximum of 30% by weight, preferably in the range from 1 to 10 wt .-%, each based on the polymer melt, blended become.

Of further mixtures are also in the mentioned volume ranges z. B. hydrophobically modified or functionalized polymers or oligomers, rubbers such as polyacrylates or polydienes, e.g. As styrene-butadiene block copolymers or biodegradable aliphatic or aliphatic / aromatic copolyesters possible.

When Compatibilizers are suitable for. B. maleic anhydride-modified Styrene copolymers, polymers containing epoxy groups or organosilanes.

As propellant come under normal conditions gaseous or liquid hydrocarbons in Question, which have a boiling point below the softening point of the polymer. Typical representatives of these compounds are propane, butane, pentane, hexane and the isomers of these compounds. Also, water, nitrogen, halogenated blowing agents or CO ₂ are useful as blowing agents. Furthermore, chemical blowing agents and blowing agents which - thermally or radiation-induced - release volatile components can be used.

When Flame retardants are especially halogenated organic compounds with a bromine content greater than 50 wt .-% for use. Known examples of these are hexabromocyclododecane, brominated styrene copolymers (For example, styrene-butadiene copolymers) or Pentabrommonochlorcyclohexan. Furthermore, all other halogenated, but also halogen-free flame retardants can be used. Possible Representatives of these substances are, for example, red phosphorus, organic phosphorus compounds, e.g. B. DOPO (9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide); DOPS-SH (9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10-thione or 10-sulfide), organic and inorganic N compounds (eg ammonium polyphosphate) inorganic compounds, e.g. For example, magnesium hydroxide; aluminum hydroxide; water glass or expanded graphite.

Furthermore, can in the polymer melts all the usual auxiliaries, such as UV stabilizers, plasticizers, pigments, dyes, organic and inorganic fillers, waxes, water repellents, Antistatic agents, antioxidants and / or acid scavengers used in any quantities.

According to the invention be provided that the expandable polymer particles, in those athermanous particles, as they are in detail above and in theirs Use described are included, to dam bodies be sintered.

From It is advantageous if in the polymer melt as blowing agent a gaseous or liquid hydrocarbon is introduced, and / or a polymer or a polymer melt is used, in which or which such a propellant already introduced.

expedient can be provided that the polymer melt from one or consists of several expandable polymers and at least one thermoplastic Contains polymer in a concentration of more than 50 wt .-% or alternatively in the polymer melt as a flame retardant an organic halogen compound, preferably with a halogen content of at least 50% by weight.

Of Further, it is advantageous if in the polymer melt used as a flame retardant halogen-free flame retardant becomes.

After all A method has proven to be favorable in which at least one thermal radical generator in the polymer melt is used as Flammschutzsynergist.

The invention will now be explained, without limiting the general idea of the invention, by means of the following advantageous examples:
In a first series of experiments (Examples 1.1 to 1.6), the time required for the comminution of selected raw materials was determined.
In a second series of experiments (Examples 2.1 to 2.6), the effectiveness of the athermanous particles on the reduction of thermal conductivity was investigated.

Test series 1:

The following are, see Table 1, the time required for the processing of some raw materials (pre-shredded and classified to 2.5 to 5 mm) to platelet-shaped particles in an air jet mill to a mean particle diameter d ₅₀ smaller than 7 microns and an aspect ratio greater than 25 and the determined Percentages of graphite areas listed. The time required for the processing of natural graphite (Comparative Example 1.1) was set here as a reference at 100%. Table 1: grade Share of graphite areas (%) time required Example 1.1 natural graphite > 99% 100% Example 1.2 Petroleum coke A 0.22% 120% Example 1.3 Petroleum coke B 0.58% 119% Example 1.4 Petroleum coke C 4.37% 107% Example 1.5 Petroleum coke D 0.00% 121% Example 1.6 Meta-anthracite 70.0% 101%

Out Table 1 shows that the proportion of graphite areas positive on the time required and thus directly on the energy needs for processing to platelet-shaped Particles affects.

Test series 2:

Example 1 (comparative example): (4% by weight Natural graphite, fraction of ordered layers> 99%)

A styrene polymer (SUNPOR EPS-STD: 6 wt .-% pentane, chain length Mw = 200,000 g / mol, nonuniformity Mw / Mn = 2.5) was 4 wt .-% natural graphite, milled to an average particle diameter d in the feed area of a twin-screw extruder ₅₀ of 7 microns and an aspect ratio between 30 and 40, and 1.8 wt .-% HBCD, both based on the resulting EPS granules, mixed and melted in the extruder at 190 ° C. The polymer melt thus obtained was conveyed through a die plate at a rate of 20 kg / h and granulated with a pressurized underwater granulator to form compact EPS granules.

The resulting granules were coated with customary for this purpose coating materials (glycerol or zinc stearates) to prevent sticking during the foaming process and then prefoamed in a batch prefoamer to a density of 16 kg / m ³ . The cell structure of the foam beads thus obtained was homogeneous. After an intermediate storage of 24 hours, blocks of dimensions 600 × 600 × 190 mm were prepared and cut by means of hot wire into plates with a thickness of 50 mm. The two middle plates were used after storage to constant weight for the measurement of thermal conductivity.

The plates thus produced had a density of 16 kg / m ³ and a thermal conductivity of 30.5 [mW / (m · K)]. The class B1 after DIN 4102 could be reached.

Example 2: (4% by weight high temperature treated Petroleum coke, fraction of ordered layers 4.4%)

The preparation of the granules and the processing into plates was carried out analogously to Example 1 with the difference that 4 wt .-% high temperature treated petroleum coke, which was partially graphitized at 1900 K, ground to a mean particle diameter d ₅₀ of 7 microns and an aspect ratio between 30 and 40 and a share of 4.4% ordered layers were used.

The plates thus produced had a density of 16 kg / m ³ and a thermal conductivity of 30.2 [mW / (m · K)]. The class B1 after DIN 4102 could be reached.

Example 3: (4% by weight of meta-anthracite, proportion ordered layers 70%)

The preparation of the granules and the processing into plates was carried out analogously to Example 1 with the difference that 4 wt .-% meta-anthracite, ground to an average particle diameter d ₅₀ of 7 microns and a proportion of 70% ordered layers were used.

The plates thus produced had a density of 16 kg / m ³ and a thermal conductivity of 30.3 [mW / (m · K)]. The class B1 after DIN 4102 could be reached.

Example 4 (comparative example): (8% by weight Natural graphite, fraction of ordered layers> 99%)

The Production of the granules and processing into plates took place analogous to Example 1 with the difference that 8 wt .-% natural graphite were used.

The plates thus produced had a density of 16 kg / m ³ and a thermal conductivity of 29.6 [mW / (m · K)]. The class B1 after DIN 4102 could be reached.

Example 5: (8 wt% high temperature treated Petroleum coke, fraction of ordered layers 4.4%)

The Production of the granules and processing into plates took place similar to Example 2 with the difference that 8 wt .-% high temperature treated Petroleum coke were used.

The plates thus produced had a density of 15.3 kg / m ³ and a thermal conductivity of 29.2 [mW / (m · K)]. The class B1 after DIN 4102 could be reached.

Example 6: (8 wt.% Meta-anthracite, Proportion of ordered layers 70%)

The Production of the granules and processing into plates took place analogous to Example 1 with the difference that 8 wt .-% meta-anthracite were used.

The plates thus produced had a density of 16 kg / m ³ and a thermal conductivity of 29.4 [mW / (m · K)]. The class B1 after DIN 4102 could be reached.

• ^*) ... Anteil grafitischer Bereiche

This results in a summary of the results shown in Tables 2 and 3: TABLE 2 example kind Wt .-% AgB ^*) (%) Density kg / m ³ WLF mW / (m · K) 1 (comparison) natural graphite 4 > 99% 16 30.5 ₂ High temperature treated petroleum coke 4 4.4% 16 30.3 3 Meta-anthracite 4 70% 16 30.2 Table 3: example kind Wt .-% AgB ^*) (%) Density kg / m ³ WLF mW / (m · K) 4 (comparison) natural graphite 8th > 99% 16 29.6 ₅ High temperature treated petroleum coke 8th 4.4% 16 29.2 6 Meta-anthracite 8th 70% 16 29.4

• ^*) ... proportion of graphite areas

Out Table 2 clearly shows that the thermal insulation capacity of insulating boards with natural graphite is worse than of Dam plates, the meta-anthracite or high-temperature petroleum coke contained in equal concentrations.

Also Table 3 shows that the comparative insulating panel 4 performs worse in terms of thermal insulation, as the two plates according to the invention.

It is thus the use of the particles according to the invention more advantageous than those with an addition of pure graphite.

The bodies according to the invention are thus both in terms of their thermal insulation advantageous as comparison plates of the same density as at the same time very much easy to produce and with little time.

• 1. Verfahren zur Herstellung eines Polymerschaumkörpers nach einem der Ansprüche 1–16, wobei die expandierbaren Polymerisatpartikel, in denen athermane Partikel gemäß einem der Ansprüche 1 bis 16 enthalten sind, zu Dammkörpern versintert werden.
• 2. Es ist bevorzugt, wenn bei diesem Verfahren in die Polymerisatschmelze als Treibmittel ein gasförmiger oder flüssiger Kohlenwasserstoff eingebracht und/oder ein Polymerisat oder eine Polymerisatschmelze eingesetzt wird, in welches bzw. welche ein derartiges Treibmittel schon eingebracht ist.
• 3. Die Verfahrenslehre nach vorstehenden Punkten 1 oder 2 lässt sich vorteilhaft dadurch weiterbilden, dass die Polymerisatschmelze aus einem oder mehreren expandierbaren Polymeren besteht und zumindest ein thermoplastisches Polymer in einer Konzentration von mehr als 50 Gew.-% enthält.
• 4. Die oben dargestellten Verfahrenslehren können zweckmäßigerweise dadurch mit Vorteil weitergebildet werden, dass in der Polymerisatschmelze als Flammschutzmittel eine organische Halogenverbindung, vorzugsweise mit einem Halogengehalt von mindestens 50 Gew.-%, eingesetzt wird.
• 5. Es hat sich gezeigt, dass es von Vorteil für die oben beschriebenen Verfahrenslehren ist, wenn in der Polymerisatschmelze als Flammschutzmittel ein halogenfreies Flammschutzmittel eingesetzt wird.
• 6. Weitergehende Vorteile ergeben sich bei zweckmäßigen Ausgestaltungen der oben beschriebenen Verfahrenslehren, wenn in der Polymerisatschmelze zumindest ein thermischer Radikalbildner als Flammschutzsynergist eingesetzt wird.

For the preparation of the polymer foam bodies according to the invention according to at least one of the protection claims 1-17 shown below, it is possible with great advantage to proceed according to the processes described below:

• 1. A process for producing a polymer foam body according to any one of claims 1-16, wherein the expandable polymer particles, in which athermane particles are contained according to one of claims 1 to 16, are sintered into dam bodies.
• 2. It is preferred if, in this process, a gaseous or liquid hydrocarbon is introduced into the polymer melt as blowing agent and / or a polymer or a polymer melt is used into which or which such blowing agent has already been introduced.
• 3. The methodology according to points 1 or 2 above can advantageously be further developed in that the polymer melt consists of one or more expandable polymers and contains at least one thermoplastic polymer in a concentration of more than 50 wt .-%.
• 4. The process teachings described above can advantageously be further developed by using an organic halogen compound, preferably having a halogen content of at least 50% by weight, as the flame retardant in the polymer melt.
• 5. It has been found that it is advantageous for the process teachings described above, if a halogen-free flame retardant is used as a flame retardant in the polymer melt.
• 6. Further advantages result in expedient embodiments of the method teachings described above, if at least one thermal radical generator is used as flame retardant synergist in the polymer melt.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 0668139 [0004]
• WO 2004065468 [0009]
• - EP 620246 [0012]
• WO 0043442 [0013]
• WO 9745477 [0014]
• WO 9851734 [0015]
• WO 2010031537 [0016]

Cited non-patent literature

• - DIN 18164 [0007]
• - DIN 18164 [0008]
• - DIN 18164 [0009]
• - DIN 4102 [0079]
• - DIN 4102 [0081]
• - DIN 4102 [0083]
• - DIN 4102 [0085]
• - DIN 4102 [0087]
• - DIN 4102 [0089]

Claims (17)

Polymer foam body or expandable polymers for further processing into a polymer foam body, in particular particulate expandable polymer particles containing carbon-containing athermane particles, characterized in that the carbon of the athermanous particles is present both partially graphitic ordered and turbostratic. Polymer foam body or polymers according to claim 1, characterized in that the scattering intensity depends on the scattering vector q of the d ₀₀₂ reflection of the carbon corresponding to the arrangement of the graphene planes of the turbostatic region at least a relative maximum in the range of 17.5 nm ^-1 and 18.6 nm ^-1 and the graphitically ordered region has at least a relative maximum in the range of 18.6 nm ^-1 and 18.9 nm ^-1 , each measured by means of small-angle X-ray scattering SAXS (small-angle X-ray scattering, wavelength λ = 0 , 1542 nm, CuKα) with a rotating anode. Polymer foam bodies or polymers according to claim 1 or 2, characterized in that the scattering intensity depends on the scattering vector q of the d ₀₀₂ reflection of the carbon corresponding to the arrangement of the graphene planes of the turbostratic region and the d ₀₀₂ reflection corresponding to the arrangement of the graphene planes of the graphitically ordered region has a common peak maximum in the range of 18.5 to 18.75 nm ^-1 . Polymer foam body or polymers according to one of claims 1 to 3, characterized in that the area below the q-curve of the d ₀₀₂ -reflexes of the graphitic region of the carbon is greater than 0.5%, preferably greater than 1%, particularly preferably greater than 2%, in each case based on the area below the q-curve in the range from 15.0 nm ^-1 to 21.0 nm ^-1 . Polymer foam body or polymers according to one of claims 1 to 4, characterized in that the area below the q-curve of the d ₀₀₂ -reflexes of the graphitic region less than 95%, preferably less than 85%, in particular less than 75%, in each case based on Area below the q-curve in the range of 15.0 nm ^-1 to 21.0 nm ^-1 . Polymer foam body or polymers according to any one of claims 1 to 5, characterized in that the largest dimension of the athermanous particles is a d ₅₀ from 0.5 to 50 microns, preferably from 1 to 30 microns, in particular from 1 to 10 microns. Polymer foam body or polymers after one of claims 1 to 6, characterized in that the athermanous particles are platelike and have an aspect ratio of 2 to 50. Polymer foam body or polymers after one of claims 1 to 7, characterized in that the athermanous particles in amounts of 0.1 to 20 wt .-%, preferably from 0.5 to 15% by weight, particularly preferably from 1 to 10% by weight, each based on the total weight of the molding or each polymer particle, are included and / or that the athermanen Particles homogeneous and uniform in the polymer are distributed. Polymer foam body or polymers after one of claims 1 to 8, characterized in that the atherman particles of natural and / or synthetic graphitizable carbons are made, at least in part transformed into graphitic structures by thermal treatment were, z. As from coal, cokes, products from the processing fossil resources, and / or natural origin, and in the geological transition state of non-graphitic Structures to graphitic structures are located, such. Anthracite, graphitic rocks or carbon rocks. Polymer foam body or polymers after one of claims 1 to 9, characterized in that additionally one or more infrared radiation reflective Particles or infrared opacifiers or the thermal insulation properties improving material (s), such as Graphite, electrographite, carbon black, carbon, activated carbon, metal oxides, For example, titanium dioxide, non-metal oxides, metal powder, aluminum powder, Carbon, e.g. B. Carbon Black, Books and Taylor structures containing Carbon, carbon fibers, fullerenes, or organic dye, in particular in the form of pigments or mixtures of these materials. Polymer foam body or polymers according to one of claims 1 to 10, in particular styrene polymer foam or extruded polystyrene rigid foam (XPS), or expandable or expan diene styrene polymers (EPS) or styrene polymer granules (EPS) consisting of homopolymers and copolymers of styrene, preferably glass clear polystyrene (GPPS), impact polystyrene (HIPS), anionically polymerized polystyrene or impact polystyrene (A-IPS), styrene-alpha Methylstyrene copolymers, acrylonitrile-butadiene-styrene polymers (ABS), styrene-acrylonitrile (SAN) acrylonitrile-styrene-acrylic esters (ASA), methyl acrylate-butadiene-styrene (MBS), methyl methacrylate-acrylonitrile-butadiene-styrene (MABS) polymers or Mixtures thereof or with polyphenylene ether (PPE) or polyphenylene sulfide (PPS). Polymer foam body or polymers after any one of claims 1 to 11 consisting of cellulose acetate butyrate and / or its copolymers and polymer blends. Polymer foam body according to one of claims 1 to 12, characterized in that its thermal conductivity at least meets the requirements of the heat conduction group WLG 032 according to DIN 18164 and / or that its thermal conductivity λ _{10, tr} , measured according to EN 12677 is below 0.031 W / m · K. Polymer foam body according to one of claims 1 to 13, having a density of ≤ 30 kg / m ³ , preferably of ≤ 18 kg / m ³ . Polymer foam body according to one of the claims 1 to 14, made of a mixture of expandable or expanded polymer particles in which athermane particles according to a of claims 1 to 10 are included, and expandable or expanded polymer particles which are free of athermanous particles are. Polymer foam body made of expandable Polymers according to one of Claims 1 to 15. Use of the polymer foam body after one of claims 1 to 16 as a dam body for thermal insulation of buildings and / or building parts.