Molded parts of flame-retardant elastomer compositions for structural fire protection, and methods for manufacturing the corresponding molded parts.

Abstract

The present invention relates to a molded part for structural fire protection, which can be produced or has been produced by vulcanizing a flame-retardant elastomer composition comprising a polymer blend of a double bond-containing elastomer and a vinyl acetate-containing thermoplastic polymer, and a crosslinker system comprising a sulfur crosslinker or a sulfur-containing crosslinker and a peroxide crosslinker, and which comprises at least one flame retardant, wherein the sulfur crosslinker or the sulfur-containing crosslinker is present in the crosslinker system in an amount greater than the peroxide crosslinker. The present invention further relates to a corresponding method for producing such a molded part, and to the use of such a molded part for applications with a minimum approved use temperature of -40°C or less.

Description

Technical Field

[0001] Description The present invention relates to a molded part for structural fire protection that can be produced or has been produced by vulcanizing a flame - retardant elastomer composition comprising a double - bond - containing elastomer and a vinyl acetate - containing thermoplastic polymer, a cross - linking agent system comprising a sulfur cross - linking agent or a sulfur - containing cross - linking agent and a peroxide cross - linking agent, and at least one flame retardant, wherein the sulfur cross - linking agent or the sulfur - containing cross - linking agent is present in the cross - linking agent system in a greater amount than the peroxide cross - linking agent. The present invention further relates to a method for producing a corresponding molded part and to the use of the molded part for applications with a minimum allowable use temperature of - 40°C or lower.

Background Art

[0002] For example, elastic elements made of rubber or raw rubber do not inherently have the flame retardancy or fire resistance required in some applications, at least in part based on standards or regulations. It is known that flame retardants or fire retardants can be added to elastomers or rubber or natural rubber to impart the desired flame retardancy. However, such additives usually reduce the elastic properties, and as a result, such elements made of rubber or raw rubber often cannot meet or can no longer meet the required elastic properties regarding the desired static and dynamic properties. Thus, for example, in a vehicle, when used as a spring element, damping element or similar element that usually receives high dynamic loads, it is impossible to fully meet the required fire protection regulations.

[0003] Due to this problem, it has been suggested that instead of making the entire element from an elastomer with a flame retardant, only a flame retardant coating should be provided on such an element. Such composite elements are described, for example, in German Patent Application Publication No. 3831894 or International Publication No. 2010 / 069842.

[0004] Essential to the properties of an elastomer is the crosslinking agent system used to transform initially fluid rubber into an elastomer material with typical elastomer characteristics. Properties such as hardness, modulus of elasticity, strength, elongation at break, tear resistance, and elasticity can be adjusted to desired levels by the type and density of crosslinking.

[0005] Furthermore, polymer compositions containing flame retardants, which can be formed from, for example, a mixture of ethylene vinyl acetate and ethylene propylene diene monomer rubber, are well known from the prior art. These mixtures are partially crosslinked using silane, but are mostly crosslinked by peroxide or irradiation.

[0006] Such mixtures are primarily used for coating cables or electric wires. For example, European Patent Application Publication No. 2343334 describes flame-retardant compositions of EVA, EPDM, and LLDPE crosslinked with a dicumyl peroxide-based peroxide crosslinking agent system. Peroxides are often used as crosslinking agents when crosslinking rubber that does not contain double bonds, and / or especially when high crosslinking density is required to achieve a tight mesh structure, which in turn positively affects mechanical properties such as compression set, especially at high temperatures. On the other hand, high crosslinking density and short crosslinking bridges usually result in lower elongation at fracture compared to materials of the same hardness. If the surface of the product is not further treated, peroxide crosslinking requires the removal of atmospheric oxygen during the crosslinking process. Furthermore, peroxide crosslinking agents negatively affect elastic and dynamic properties, especially when the composition also contains a large amount of flame retardant. Finally, periodic crosslinking agents also have the disadvantage of being relatively expensive, especially compared to sulfur as a crosslinking agent.

[0007] To solve these problems, European Patent No. 2880093 proposes a mixture of a double-bond-containing elastomer, such as EPDM, vulcanized with sulfur or a sulfur-containing crosslinking agent system, and a vinyl acetate-containing thermoplastic polymer, such as EVA. The sulfur crosslinking agent is intended to ensure that only the double-bond-containing elastomer is involved in crosslinking and that a material with high elongation at the breaking point is obtained.

[0008] In structural fire prevention, people typically attempt to prevent the passage of smoke and gases, as well as the transfer of heat from a fire from one room to the next, or from different building areas to adjacent areas. Clearly, for fire prevention purposes, the closure of passages in walls or ceilings between adjacent rooms or building areas must be considered. Of particular importance here are passages for electrical wires and piping or ventilation flaps.

[0009] Conventional elastomer materials that can be used for sealing purposes often utilize sulfur crosslinking agents, which are said to provide advantageous dynamic properties and good fillability due to flame retardants. Here, as an example, refer to the aforementioned European Patent No. 2880093. However, these materials do not possess optimal properties with respect to glass transition temperature. While the glass transition temperature affects the potential operating temperature of a material, below this temperature, the material loses its flexibility and can no longer provide the desired elastomer properties. Against this backdrop, it is desirable to have materials for producing structural fire-resistant molded articles with the lowest possible glass transition temperature in the vulcanized state, thereby broadening the temperature range that can be accommodated by such components. In other application areas, the material should provide properties as equivalent as possible to conventional materials based on double-bond-containing elastomers and vinyl acetate-containing thermoplastic polymers. A low glass transition temperature would be particularly advantageous in applications in regions and areas around the world where ambient temperatures can drop to below -40°C, such as pipeline systems in Siberia or the Arctic.

[0010] Against this backdrop, there was a need for elastomer compounds for manufacturing structural fire-resistant molded articles, and for corresponding molded articles that exhibited mechanical properties as similar as possible to those of commercially available products, but with a lower glass transition temperature and encompassing a wider range of operating temperatures. This invention addresses this need. [Modes for carrying out the invention]

[0011] In the research that forms the basis of this application, it was surprisingly discovered that when a molded article is prepared from a composition containing a double-bond-containing elastomer and a vinyl acetate-containing thermoplastic polymer, and this composition is crosslinked with a mixture of a peroxide crosslinking agent and a sulfur crosslinking agent or a sulfur-containing crosslinking agent, improved glass transition temperature characteristics and favorable elastic and mechanical properties can be obtained. In this case, a small amount of peroxide crosslinking agent is sufficient to achieve a significantly lower glass transition temperature, and as a result, the peroxide crosslinking agent can be used in mixture with a sulfur crosslinking agent or a sulfur-containing crosslinking agent. By lowering the glass transition temperature of the crosslinked molded article, the temperature range in which the molded article with elastomer properties can be used can be expanded.

[0012] Accordingly, according to a first aspect, the present invention relates to a molded part for structural fire protection that can be produced or has been produced by vulcanizing a flame-retardant elastomer composition, wherein the elastomer composition comprises i) a double-bond-containing elastomer and ii) a vinyl acetate-containing thermoplastic polymer as polymer components, wherein the polymer components exist as a homogeneous polymer mixture; a crosslinking agent system consisting of a sulfur crosslinking agent or a sulfur-containing crosslinking agent and a peroxide crosslinking agent, wherein the amount of the peroxide crosslinking agent is less than the amount of the sulfur crosslinking agent or sulfur-containing crosslinking agent; and a flame retardant or a combination of flame retardants.

[0013] In this context, the term “structural fire-resistant molded parts” refers to molded parts used in applications where the spread of fire or gas, such as fire gases, from one space to another adjacent space, or from different building areas to adjacent areas, is prevented or at least slowed. These types of molded parts are typically designed to be inserted in a shape that fits tightly into openings in walls between rooms or building areas, the cross-section of which may be circular, rectangular, or square. In contrast, cable insulation, for example, which is primarily intended to prevent the combustion of the insulation itself, is not a structural fire-resistant molded part within the scope of the present invention as described herein. Structural fire-resistant molded parts are typically dimensional based on the dimensions of the opening in which they are used; that is, the length of the molded part is greater than or equal to the wall thickness, but not significantly longer (e.g., no more than five times the wall thickness, preferably no more than twice).

[0014] In the context described herein, the term “building area” includes areas of fixed, immobile structures (“buildings”), including technical and industrial equipment, wind and solar equipment, in the land and sea sectors, which have areas or units separated from each other for fire prevention purposes to prevent gas exchange, as well as areas of movable structures, particularly ships.

[0015] The phrase "structural fire protection" does not preclude the molded part from performing other functions, such as sealing against the passage of gas, water, sound (to improve acoustics), or pathogens such as bacterial aerosols, mold, or their spores. The assumption of such functions is clearly desirable and preferred for the molded part according to the present invention.

[0016] Using only a small amount of peroxide crosslinking agent has the advantage of minimizing the cost of the crosslinking agent system.

[0017] The double bond-containing elastomer is preferably a homopolymer, copolymer, or terpolymer of diene monomer units or having diene monomer units. A terpolymer composed of ethylene, propylene, and diene-containing ter monomers is particularly preferred, and preferably the ter monomer content relative to the terpolymer is at least 2% to 12% by weight.

[0018] It is particularly advantageous when the elastomer contained in the double bond is a rubber with unsaturated side groups, especially ethylene-propylene-diene rubber (EPDM). Ethylene-propylene-diene monomer rubber (EPDM) has a significant advantage in the event of a fire due to its low smoke concentration and low toxicity, but it is not fire-resistant in itself. On the other hand, EPDM rubber can be highly filled with fillers and plasticizers and can therefore absorb a high proportion of flame retardants in solid and liquid forms. Thus, the hardness and mechanical properties of EPDM rubber can be adjusted over a wide range, and the rubber is advantageous in terms of resistance to weathering, ultraviolet rays, ozone, and heat.

[0019] EPDM rubbers particularly useful in the flame-retardant elastomer composition from which the molded article of the present invention is formed include 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-cyclopentadiene, dicyclopentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 1,4-hexadiene, 1,4-cyclohexadiene, and tetrahedron. The ethylene-propylene-diene monomer rubber (EPDM) is a terpolymer of ethylene, propylene, and 5-ethylidene-2-norbornene (ENB), 5-methylene-2-norbornene (MNB), 1,6-octadiene, 5-methyl-1,4-hexadiene, 3,7-dimethyl-1,6-octadiene, 5-iso-propylene-2-norbornene, and 5-vinyl-norbornene, and is particularly advantageous when the termonomer content relative to the terpolymer (according to ASTM D 6047) is at least 2 to 12% by weight, particularly 4 to 12% by weight. The most preferred diene component of EPDM rubber is 5-ethylidene-2-norbornene (ENB).

[0020] In the research that forms the basis of the present invention, it was also found that very favorable properties can be obtained when EPDM is formed from a mixture of two EPDM grades, one having a diene content in the range of 8 to 12% by weight and the other having a diene content in the range of 4 to 7% by weight. Furthermore, in this case, other EPDM grades may also be present, but these are preferably present in the mixture in an amount of 5% by weight or less, particularly 2% by weight or less, relative to the total amount of high-diene-content and low-diene-content EPDM. In the mixture, EPDM with a diene content in the range of 8 to 12% by weight preferably constitutes the dominant proportion of EPDM (i.e., 50 to 95% by weight, preferably 60 to 80% by weight, of the total EPDM in the mixture).

[0021] The thermoplastic vinyl acetate-containing polymer contained in the elastomer composition forming the molded article of the present invention is preferably a homopolymer, copolymer, or terpolymer of vinyl acetate, and particularly preferably polyvinyl acetate (PVAc) or ethylene vinyl acetate (EVA). For ethylene vinyl acetate copolymers, the vinyl acetate content is preferably in the range of 40 to 75% by weight, and particularly preferably in the range of 50 to 65% by weight.

[0022] Alternatively, or more preferably, the melting temperature or the starting point of the melting range of the vinyl acetate-containing polymer is less than 150°C, more preferably less than 100°C.

[0023] The ratio of polymer components i) and ii) in the elastomer composition according to the present invention is preferably in the range of 5:1 to 20:1, particularly 6:1 to 12:1, that is, the double bond-containing elastomer is present in greater quantities than the vinyl acetate-containing thermoplastic polymer.

[0024] All peroxide crosslinking agents known to those skilled in the art can be considered as peroxide crosslinking agents in the crosslinking agent system of the present invention. Dialkyl peroxides and ketal peroxides are particularly useful. Suitable dialkyl peroxides include dicumyl peroxide, di-t-butyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-bis(t-butylperoxy)-hexane, 2,5-dimethyl-2,5-bis(t-butylperoxy)-hexyne-(3), α,α'-bis(t-butylperoxy)-diisopropylbenzene, di-t-amyl peroxide, 1,3,5-tris(2-t-butylperoxyisopropyl)benzene, and 1-phenyl-1-t-butylperoxyphthalide. Suitable ketal peroxides include 1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(t-butylperoxy)-cyclohexane, 2,2'-bis(t-butylperoxy)-butane, ethyl-3,3-bis(t-butylperoxy)-butyrate, and n-nutyl-4,4-bis(t-butylperoxy)-valerate. Particularly preferred in the present invention is the use of 2,5-dimethyl-2,5-bis(t-butylperoxy)-hexane.

[0025] The ratio of the peroxide crosslinking agent to the polymer mixture is preferably 0.2 to 1.5 phr, more preferably 0.5 to 1.2 phr, where "phr" refers to the total amount of double-bond-containing elastomer and vinyl acetate-containing thermoplastic polymer contained in the polymer mixture.

[0026] A sulfur crosslinking agent (for example, in the form of pulverized sulfur), or a sulfur-containing crosslinking agent such as bis[3-(triethoxysilyl)propyl]polysulfide, or a mixture thereof may be used as the sulfur crosslinking agent in the elastomer composition of the present invention.

[0027] The ratio of sulfur crosslinking agent or sulfur-containing crosslinking agent to the polymer admixture is preferably in the range of 1 to 7 phr, particularly 2 to 5 phr, and especially preferably 2.8 to 4.0 phr.

[0028] For the purposes of the present invention, it is essential that the sulfur crosslinking agent or sulfur-containing crosslinking agent is present in a greater amount than the peroxide crosslinking agent, and "greater amount" means that the weight percentage of the total amount of the sulfur crosslinking agent or sulfur-containing crosslinking agent is higher than that of the peroxide crosslinking agent. Preferably, the peroxide crosslinking agent and the sulfur crosslinking agent or sulfur-containing crosslinking agent are present in a ratio of about 1:1.5 to 1:5, particularly 1:2 to 1:4, and particularly preferably 1:2.5 to 1:3.8.

[0029] The flame retardant contained in the molded part according to the present invention is not subject to any relevant restrictions, and the flame retardant can be, for example, an intumescent flame retardant (such as intumescent graphite) or a hydrolyzable flame retardant, such as a metal hydroxide. In order to achieve good fire protection properties while minimizing the impact on material properties, magnesium hydroxide (MDH), aluminum hydroxide (ATH), antimony trioxide, nanoclay and / or zinc borate, preferably a synergistic mixture of two or more of them, has proven to be advantageous when contained in the elastomer composition according to the present invention. Preferably, the elastomer composition according to the present invention contains aluminum hydroxide alone or in admixture with other flame retardants. In particular, the flame retardant(s) is / are solid and in powder or crystalline form.

[0030] In most cases, the flame retardant is present in a relatively high proportion in the elastomer composition. Preferably, the elastomer composition contains the flame retardant in a proportion of 100 to 300 phr, particularly 140 to 250 phr. If the flame retardant content falls below this level, in individual cases, it may no longer be possible to guarantee a sufficient flame retardant effect, while on the other hand, if the proportion of the flame retardant is higher, it may have a significantly unfavorable effect on mechanical properties such as tensile strength, elongation at break, tear resistance, or elasticity.

[0031] The elastomer composition for producing the molded body according to the present invention may contain further additives and / or auxiliaries in addition to the above components in order to preferably control the final properties of the molded body.

[0032] The primary type of additive that can be used to control vulcanization or crosslinking is accelerators, each of which can specifically promote sulfur crosslinking or peroxide crosslinking. Accelerators commonly used for sulfur crosslinking include sulfenamides, e.g., N-cyclohexyl-2-benzothiadylsulfenamide (CBS); thiazoles, e.g., 2-mercaptobenzothiazole (MBT); dithiocarbamates, e.g., zinc dibenzyldithiocarbamate (ZBEC) or zinc dibutyldithiocarbamate (ZDBC); guanidines, e.g., diphenylguanidine (DPG); or thiophosphates. Suitable sulfur donors that can be added to control sulfur crosslinking include thiurams such as tetramethylthiuram disulfide (TMDT) or tetramethylthiuram sulfide (TMTM), caprolactam disulfides, or phosphoryl polysulfides. Such accelerators and sulfur donors may, conveniently, be included in the elastomer composition according to the present invention in a total proportion of 1 to 5 phr.

[0033] Antioxidants such as 2,2,4-trimethyl-1,2-dihydroquinoline (TMQ) or 1,3-dihydro-4(or 5)-methyl-2H-benzimidazole-2-thion can be used to support peroxide crosslinking. Such antioxidants and sulfur donors may be present in the elastomer composition in a total proportion of 1 to 5 phr.

[0034] Furthermore, the elastomer composition may contain plasticizers, for example, in the form of paraffinic mineral oil, or processing aids, for example, in the form of fatty acids, fatty alcohols, or Ca and Zn soaps of low molecular weight polyethylene or polyethylene glycol. Additionally, additives such as ZnO or MgO may be added to improve thermal stability, and / or pigments such as TiO2, UV stabilizers, or carbon black may be added to color or impart UV protection. The proportion of plasticizers is preferably in the range of 5 to 50 phr, particularly 10 to 30 phr, and more preferably 12 to 25 phr. Other aids and additives are conveniently included in the flame-retardant elastomer composition in a maximum proportion of 20 phr, particularly 15 phr.

[0035] As a flame retardant composition particularly suitable in the context of the present invention for manufacturing a molded article according to the present invention, the composition can be disclosed as follows: A mixture of a double-bond-containing elastomer and a vinyl acetate-containing thermoplastic polymer. A flame retardant with a strength of 130-250 phr, preferably in the form of aluminum hydroxide. Plasticizers of 10-30 phr, Each of the following is a sulfur donor / accelerator and antioxidant for sulfur vulcanization, ranging from 1 to 5 phr. 5-30 phr, preferably 8-15 phr of other additives and auxiliaries A crosslinking agent system comprising a sulfur crosslinking agent or a sulfur-containing crosslinking agent and a peroxide crosslinking agent, wherein the amount of the peroxide crosslinking agent is less than the amount of the sulfur crosslinking agent or sulfur-containing crosslinking agent.

[0036] For use in fire prevention purposes, it is preferable that the molded article according to the present invention, manufactured from a flame-retardant elastomer composition, does not contain a relevant amount of halogen. This is because, in the event of a fire, toxic hydrogen halides may be released from halogen-containing compounds. Therefore, in the molded article according to the present invention, it is preferable that the polymer component of the elastomer composition, preferably the entire composition, does not contain halogen.

[0037] The molded article according to the present invention can be formed solely from a flame-retardant elastomer compound, or it may contain further components, such as reinforcing agents. In one embodiment, the surface of the molded article is formed solely from a flame-retardant elastomer mixture, and another material is present inside the molded article.

[0038] As already stated, the molded part according to the present invention is a molded part that can be used for structural fire protection, and its dimensions are usually adapted to the thickness of the wall in which the molded part is used. Here, the molded part according to the present invention preferably has an aspect ratio of up to 10, and particularly preferably up to 5. Here, "aspect ratio" refers to the ratio of the maximum to the minimum spatial range of the molded part.

[0039] In a particularly preferred embodiment, the molded part according to the present invention is a ventilation flap or a component thereof. In another particularly preferred embodiment, the molded part according to the present invention is a device for a fire-resistant passage such as a conduit, cable, tube, etc., through an opening located in a wall or shaft, formed by at least one rectangular support frame. In this case, the device includes one or more packing pieces having a path of a flame-retardant elastomer composition extending across the depth of the rectangular support frame, which can be inserted into the rectangular support frame.

[0040] For clarity, it should be noted that, here, the molded part according to the present invention refers to the entire apparatus, but may be formed from multiple individual parts (in particular multiple packing pieces, and, where appropriate, further components). In this case, the rectangular support frame is not part of the apparatus.

[0041] In a preferred embodiment, the device includes at least one unit of two packing pieces formed from two symmetrically shaped sealing elements, each sealing element having one or more substantially semi-cylindrical recesses, and arranged vertically so as to form one or more cylindrical recesses. Conveniently, in this case the device may have two semi-cylindrical insert portions, each insert portion formed with a semi-cylindrical recess, and arranged opposite each other so as to form a path adapted for insertion of a conduit.

[0042] The device may include exactly two packing pieces (=1 pair), or a multiple of two packing pieces, which can be inserted into a rectangular support frame (for example, in 2x2, 3x2, 4x2, or 4x4 pair arrangements). In the case of an odd number of packing pieces, the empty space in the rectangular support frame can be filled (as a "filling module") by a molded body that precisely matches the dimensions of the empty space. It is also preferable that such filling modules be formed from the flame-retardant elastomer composition described above. Similarly, multiple such filling modules can be arranged within the rectangular support frame, which, in combination with the packing pieces, form the device.

[0043] With respect to the above-described apparatus, it is even more preferable that semi-annular ribs are formed on the wall defining the recess within the sealing element, and that semi-annular grooves are formed between these ribs. Some of these grooves may have recesses that preferably extend only over a portion of the semi-annular wall. In this embodiment, it is even more preferable that the semi-cylindrical insert portion is provided with projections corresponding to the grooves and recesses in the wall defining the sealing element, the projections engaging with the grooves and recesses so that when the insert portion is placed within the sealing element, the insert portion cannot be displaced in the direction of the path in which it is formed, nor can it rotate around this path. In this way, the insert portion inserted into the sealing element is prevented from moving or rotating. Such a sealing element is described in detail, for example, in European Patent No. 1134472, the relevant content of which is incorporated in whole by reference in this application.

[0044] If the device has a semi-cylindrical insert portion, the device may further have molded body components whose dimensions are adapted to the dimensions of the path formed by the semi-cylindrical insert portion and which may be inserted into the semi-cylindrical insert portion as placeholders for later occupying the path with cables. Preferably, these placeholders also have projections that can engage with corresponding recesses in the semi-cylindrical insert portion to fix the position of the placeholder within the insert portion. Preferably, the placeholders are also formed from the aforementioned flame-retardant elastomer composition. [Brief explanation of the drawing]

[0045] The above-mentioned apparatus is shown in detail in Figures 1 to 5. In the drawings: [Figure 1] This is a front view of a packing piece having two sealing elements. [Figure 2] This is a top view of the sealing element. [Figure 3] This is a longitudinal cross-sectional view of the sealing element. [Figure 4] This is a top view of the insert section. [Figure 5] This is a side view of the insert section.

[0046] The cubic packing piece 1 shown in Figure 1 consists of two symmetrically formed sealing elements 11, each of which is formed with a substantially semi-cylindrical recess and functions to receive a semi-cylindrical insert portion 21, which is similarly formed with a semi-cylindrical recess. The conduit 3 can be inserted into the resulting through-path. The sealing elements 11 and the insert portion 21 positioned within them must be designed to tightly enclose the conduit 3 to ensure the desired safety against the passage of fire gases.

[0047] Figures 2 and 3 show a top view and a longitudinal cross-sectional view of the sealing element 11, which has ribs 12 and grooves 13, as well as additional recesses 14 that, unlike the grooves 13, do not extend across the entire semicircular inner surface of the sealing element.

[0048] Figures 4 and 5 show a top and side view of the insert portion 21 having grooves 22, ribs 23, and projections 24. Figure 5 also shows semi-annular ribs 25 on the inner wall of the insert portion and semi-annular grooves 26 between them. The ribs can be used to compensate for differences in the thickness of the inserted cable to the extent that the ribs can push aside with a given flexibility. When the insert portion is inserted into the sealing element, the ribs 23 and projections 24 engage with the corresponding grooves 13 and recesses 14 of the sealing element.

[0049] In a further embodiment, the present invention relates to the use of a molded part for structural fire protection applications, as described in detail above, wherein the molded part is preferably inserted into a wall opening or a wall opening between two rooms, and seals the opening in the contact area between the molded part and the wall. In such applications, piping or other conduits may be integrated with or inserted into the molded part.

[0050] In a further embodiment, the present invention relates to a method for manufacturing the above-described molded article, a) A step of mixing the aforementioned polymer components to form a homogeneous mixture, and in particular, subsequently incorporating a crosslinking agent system, a flame retardant and optionally further additives and / or auxiliary agents while avoiding crosslinking and / or vulcanization, b) A step of introducing the aforementioned mixture into a mold, c) Next, the mixture mentioned above is vulcanized, d)c) A step to release the molded body formed in the previous step, Regarding methods including

[0051] The mixing is conveniently carried out under conditions where crosslinking or vulcanization does not occur, i.e., preferably at a temperature of 110°C or lower. Subsequent vulcanization can be carried out at a high temperature, for example, in the range of 130°C to 200°C, particularly 130°C to 170°C, and optionally under pressure. During vulcanization, crosslinking of the polymer components occurs as a result of the activation of the crosslinking agent.

[0052] The elastomer composition used to manufacture the molded article according to the present invention preferably has at least one of the following properties after vulcanization. i) Glass transition temperature measured by DSC, with a maximum of -39°C, particularly a maximum of -40°C, and especially preferably a maximum of -41°C. ii) A compression set in the range of 10-40%, preferably 15-25%, measured at 70°C / 24 hours according to DIN ISO 815, and / or a compression set in the range of 45-75%, preferably 55-68%, measured at 100°C / 24 hours according to DIN ISO 815. iii) Shore A hardness of 65 to 85, preferably 70 to 83, as measured according to DIN ISO7619-1(2012), iv) Breaking elongation of 200-600%, preferably 300-500%, as measured according to DIN53504. v) Tear resistance of >2.5 N / mm, preferably >3.5 N / mm, as measured according to DIN ISO34-1A.

[0053] A further aspect of the present invention relates to the use of the above-described molded parts for applications where the minimum permissible operating temperature is -40°C or lower. Preferred applications of this type include, in particular, buildings, technical and industrial equipment, wind and solar equipment in the land and sea sectors, as well as through-holes in the walls or ceilings of ships, or similar pipelines and cables, when located in regions and areas around the world where very low outdoor temperatures in the range of -40°C may occur.

[0054] A further aspect of the present invention relates to the use of the above-mentioned molded parts for sealing buildings against water, gas, sound, or pathogens, particularly pathogens in the form of bacteria or fungi.

[0055] With respect to these embodiments, preferred embodiments described in relation to molded parts according to the present invention are also preferred in similar forms, as long as they do not conflict with each other.

[0056] In the following, this application will be described in more detail by several embodiments, but these embodiments should not be considered to limit the scope of this application. [Examples]

[0057] The compositions shown in Table 1 below were homogenized in a mixer and then vulcanized at 180°C for 10 minutes (2 mm thick sheet) or 20 minutes (6 mm thick sheet) under a nitrogen atmosphere. Subsequently, the mechanical properties of the plates were measured. To measure the glass transition temperature, the mixture was first equilibrated at -120°C for 15 minutes and then heated to 250°C at a heating rate of 10 K / min. The glass temperature was measured as the midpoint Tg according to DIN 51007. The measured mechanical properties are also shown in Table 1 below.

[0058] [Table 1]

[0059] Table 1 clearly shows that, despite otherwise equivalent mechanical properties, crosslinking with sulfur and peroxide accelerators resulted in a decrease in the glass transition temperature of approximately 2.6°C. This change makes it possible to use elastomer formulations suitable for applications at very low, extreme temperatures.

[0060] In a similar measurement of the glass transition temperature in an air atmosphere, a Tg of -41.5°C was measured for E1 and a Tg of -39.1°C was measured for V1 (average of two measurements).

Claims

1. A molded component for structural fire protection, manufactured by vulcanizing a flame-retardant elastomer composition, The aforementioned flame-retardant elastomer composition, A double-bond-containing elastomer and a vinyl acetate-containing thermoplastic polymer as polymer components, wherein the polymer components exist as a homogeneous polymer mixture, A crosslinking agent system comprising a mixture of a sulfur crosslinking agent and a peroxide crosslinking agent, or a mixture of a sulfur-containing crosslinking agent and a peroxide crosslinking agent, wherein the amount of the peroxide crosslinking agent is less than the amount of the sulfur crosslinking agent or sulfur-containing crosslinking agent, A molded part containing a flame retardant or a combination of flame retardants.

2. The molded part according to claim 1, characterized in that the peroxide crosslinking agent is present in the polymer admixture of the flame-retardant elastomer composition in a proportion of 0.2 to 1.5 phr.

3. The molded part according to claim 1 or 2, characterized in that the sulfur crosslinking agent or sulfur-containing crosslinking agent is present in the polymer admixture of the flame-retardant elastomer composition in a proportion of 1 to 7 phr.

4. The molded part according to claim 1, characterized in that the double bond-containing elastomer in the flame-retardant elastomer composition is a homopolymer, copolymer or terpolymer of diene monomer units, or a homopolymer, copolymer or terpolymer having diene monomer units.

5. The molded part according to claim 1, characterized in that the double bond-containing elastomer in the flame-retardant elastomer composition is a rubber having an unsaturated pendant group.

6. The molded part according to claim 1, characterized in that the vinyl acetate-containing thermoplastic polymer in the flame-retardant elastomer composition is a homopolymer, copolymer, or terpolymer of vinyl acetate.

7. The molded part according to claim 1, characterized in that the double bond-containing elastomer and the vinyl acetate-containing thermoplastic polymer in the flame-retardant elastomer composition are present in the elastomer composition in a ratio of 5:1 to 20:

1.

8. The molded part according to claim 1, characterized in that the peroxide crosslinking agent in the flame-retardant elastomer composition is present in the composition in the form of a dialkyl peroxide and / or ketal peroxide.

9. The molded part according to claim 1, characterized in that the flame retardant in the flame-retardant elastomer composition is selected from the group comprising metal hydroxides and zinc borate.

10. The molded part according to claim 1, characterized in that the flame retardant is present in the flame retardant elastomer composition in a proportion of 100 to 300 phr of the elastomer composition.

11. The molded part according to claim 1, characterized in that the flame-retardant elastomer composition further comprises at least one additive and / or auxiliary selected from the group consisting of a colorant, a plasticizer, an antioxidant, and a crosslinking accelerator.

12. The molded part according to claim 1, characterized in that the polymer component of the flame-retardant elastomer composition does not contain halogens.

13. The molded part according to claim 1, characterized in that the vulcanized flame-retardant elastomer composition forming the molded part has a Shore A hardness in the range of 65 to 85 and / or a glass transition temperature of up to -39°C, as measured in accordance with DIN ISO 7619-1 (2012).

14. The molded part according to claim 1, characterized in that the aspect ratio is a maximum of 10.

15. A molded part according to claim 1, designed as a device for a fire-resistant passage for conduits, cables, and tubes through an opening in a wall or shaft having at least one rectangular support frame, wherein the device has one or more packing pieces (1) having a path of elastic material extending over the depth of the rectangular support frame, the packing pieces being insertable into the rectangular support frame.

16. The molded part according to claim 15, wherein the device includes a plurality of packing pieces (1) formed from two symmetrically formed sealing elements (11), the sealing elements (11) having substantially semi-cylindrical recesses and being arranged vertically so as to form cylindrical recesses.

17. The molded part according to claim 16, wherein a semi-annular rib (12) is formed on the wall defining the recess of the sealing element (11), and a semi-annular groove (13) is formed between these ribs.

18. The molded part according to claim 17, wherein the semi-cylindrical insert portion (21) comprises ribs (23) and projections (24) corresponding to the grooves (13) and recesses (14) of the wall defining the sealing element (11), and when the insert portion (21) is placed inside the sealing element (11), the insert portion engages with the grooves (13) and recesses (14) such that the insert portion cannot be displaced in the direction of the formed path or rotated around the path.

19. A method for manufacturing a molded article according to claim 1. A step of mixing the polymer components described in claim 1 to form a homogeneous mixture, A step of introducing the mixture into a mold, Next, the mixture is vulcanized, A method comprising the step of demolding the molded body formed in the above step.

20. Use of the molded part according to claim 1 for buildings, technical and industrial equipment, wind and solar power equipment, and for penetrations in the walls or ceilings of ships in the land and sea sectors.

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