KR900003433B1 - Fire resistant material - Google Patents

Abstract

6-100 pts. by wt. of an ethylene copolymer matrix (I), 50-450 pts. by wt. of an aluminium hydroxide (II), and 150-600 pts. by wt. of a cpd. (III) selected from calcium carbonate and calcium-magnesium caronate. The compsn. further includes 11-30 pts. by wt. of an elasticiser (IV), 0-10 pts. by wt. of a polymer softening agent (V), 8-15 pts. by wt. of a lubricating agent (VI), 8-15 pts. by wt. of calcium oxide (VII) and 1 pt. by wt. of a colouring agent (VIII), and opt. an antioxidant (IX).

Description

Flame retardant

1 is a device for controlling the thermal stability of products A, C and P.

2 is the TG curve of samples under nitrogen atmosphere.

3 is the TG curve of samples under oxygen atmosphere.

4 is the DTA curve of samples under nitrogen atmosphere.

5 is the DTA curve of samples under oxygen atmosphere.

The present invention relates to a flame barrier material, and more particularly to a high temperature, high heat shield material having selectivity and thermal stability at elevated temperatures. Until now, various substances have been proposed as flame barrier materials. For example, in the field of refractory cable transistors, the above materials based on neoprene, silicone foam, inorganic molding material and inorganic wool mat have been used. These known materials exhibited thermal insulation and fire resistance, while on the other hand, (1) good thermal conductivity under normal use conditions, (2) foaming and filling at elevated temperatures, and (3) thermal insulation at very high temperatures. And no mechanical protection. However, the present invention relates to the above mentioned properties as well as to flame retardants which have additional functionality and flame retardancy and can be prepared using relatively economical methods and components. Under fire or elevated temperatures, the flame retardant of the present invention exhibits the basic two properties of providing active (active) thermal protection by a protective material that requires protection: (1) Foam and endothermic reactions occur at predetermined elevated temperatures. One of the end products of this endothermic reaction is water, which, when evaporated, impedes the exotherm at the thermal contact surface and acts as a foaming agent.

(2) The material of the present invention is converted into a foamed polymer foam under the form of direct heating, that is, like a layer having a ceramic structure. This foam layer protects the unexposed portions of the thermal protective material and has good thermal insulation at temperatures above 2300 ° F.

Thermal barrier properties in the materials of the present invention are present only at temperatures above 200 ° C. Above 200 ° C., the polymeric matrix component of the material is foamed to form a porous insulating material. At the same time, water vapor is dissipated, impeding the increase in temperature and forming a non-combustible atmosphere in the material of the present invention. During the foaming process, the material of the present invention was foamed approximately 30-40% onto the shipboard material (ie 100% by volume). Below 200 ° C., the material of the present invention is a relatively good thermal conductor and thus dissipates excess heat. Upon thermal contact the material softens at about 95 ° C. This is because the melt viscosity of the material is very high and the unloaded specimens retain their material form upon heating, foaming and sintering. In addition, the material of the present invention did not drip during the softening and combustion steps. In general, the flame barrier material of the present invention is a composition based on a high density polymer, the main components of which are ethylene copolymers, aluminum hydroxide (ie, Al (OH) ₃ ), and calcium carbonate. Such flame retardants are solids which have good physical and chemical properties, which are extruded or molded or coated at environmental temperatures.

When the flame barrier material of the present invention is heated to an environmental temperature of 1200 ° C., a series of complex chemical and physical conversions occur to the material. When the material of the present invention is cooled from a suitable high temperature, the cooling material is characterized in that it is a porous mechanical solid and mainly inorganic material. In this heat-cooling operation, the thermal conductivity of the material was reduced to 1/10 of the thermal conductivity of the original state material. In addition, the thermal barrier effect of the material of the present invention was very complicated. The result of the change in the material is well described by observing the method when the flame retardant slab of the present invention is heated on one side of an input high heat source of about 1200 ° C.

Under these conditions, the flame barrier material begins to soften on the surface in direct contact with the heat source. As the temperature of the surface increases to about 200 ° C., surface softening gradually increases, and the temperature wire moves rapidly to the polymerization matrix due to the relatively high thermal conductivity. The ethylene copolymer is not substantially soluble, but rather pyrolyzes from the softened state. However, when the polymer is chemically stable and soft at about 200 ° C., aluminum hydroxide begins to decompose and the decomposition degree increases until it reaches about 300 ° C. to complete the decomposition at this temperature. contains Al ₂ O ₃ (reference: the aluminum trihydrate neum 1kg calculates a water 365g, for example, a preferred composition of the present invention calculates 1kg water 252g). During this conversion, the submerged radicals rapidly dissipate to form the foam of the polymer matrix. Calcium carbonate and / or magnesium carbonate together with the aluminum oxide residue are dispersed into the resulting polymer matrix foam. At this temperature the flame barrier showed a foam structure characterized by low thermal conductivity, but was still a polymer matrix.

The carbonates were further heated to convert these oxides. An inorganic bubble structure composed of a combination of calcium magnesium and aluminum oxide is shown.

A surprising feature of the present invention is that such a bubble structure has sufficient mechanical preservation and is self-supporting and exhibits sufficient durability against mechanical shock. In particular, even the carbon in the polymer and the barrier material is thermally decomposed into carbon monoxide and carbon dioxide at elevated temperatures. Therefore, on the surface of the flame barrier material in contact with the high temperature, endothermic phenomenon occurs during decomposition of aluminum hydroxide as encountered during combustion. The endotherm by decomposition is ₃₀₀ KJ / mol Al ₂ O ₃ according to the following reaction, that is, 2Al (OH) ₃ → Al ₂ O ₃ + 3H ₂ O, thereby limiting the temperature rise unless aluminum hydroxide is decomposed. Moreover, steam is generated and the polymer matrix forms a foam while reducing the thermal conductivity. The positive effects combine to reduce the heat flux to the underlying soft polymeric material. Therefore, when the flame shielding material of the present invention is heated at a suitable elevated temperature as described above, a foaming layer is formed to contact the heat source, but a part of the material is further separated from the heat source and thus does not perform the foaming step only by the endothermic reaction.

The flame barrier material of the present invention is free of halogen, sulfur, phosphoric acid and other components that give off acidic products upon combustion. Moreover, dense smoke is generated from the material of the invention and is hardly observable upon combustion. Rather, a small amount of pale gray smoke was observed. The smoke level was measured by the Arapahoe apparatus (gravity method) and showed less than 0.5% by weight of smoke in the combustion material. This confirms that the smoke generated during combustion is not dense.

The flame barrier material of the present invention is in a rigid or flexible phase up to a predetermined limit (at least 20% elongation at break). It may also be laminated or reinforced by conventional materials.

Flame barrier materials of the invention are used, for example, in the manufacture of walls, floors, ceilings, rooms and cabins that require protection in case of fire. It is also useful as a shield or cover for mechanical electrical devices such as electrical cabinets or housings, fittings, pipes, hoses, cables, panels, cable transitions, dough and hatches. Moreover, it is also used as a protective cover for tanks and pipes, housings or small explosive materials and is also found in chemicals, refineries, machinery, ships and aircraft. On the other hand, the flame barrier material is provided in the form of particles of a desired shape or size and is useful as an insulating material between the inner surface and the outer surface of a storage tank or tower, especially a storage unit composed of large members. Due to these particulates, the flame barrier material of the present invention is easily filled in the spaces between the surfaces to form desirable heat insulating means. As the particles are filled in the spaces between the surfaces, they are foamed and melted together to form a rigid, foamable intermediate layer without applying inadequate pressure to the surface.

The flame barrier material of the present invention is 60-100 parts by weight of an ethylene copolymer: 0-40 parts by weight of an elastomer such as rubber: 0-10 parts by weight of a polymer softener such as polyisobutylene; 0-15 parts by weight of a lubricant such as paraffin wax: 0-15 parts by weight of calcium oxide: 50-450 parts by weight of aluminum hydroxide: 150-600 parts by weight of calcium carbonate or calcium carbonate-magnesium, for example, about 1 weight Includes colorants such as carbon black. Ethylene copolymers include ethylene-vinyl acetate: ethylene-acrylic acid; Ethylene-methacrylic acid: ethylene-ethylacrylate: ethylene-vinyl acetate-methacrylic acid: ethylene-isobutyl acrylate: ethylene-methyl methacrylate and ethylene-vinyl acetate-carbon monoxide . Ethylene-ethyl acrylate is preferred.

Through the embodiment of the present invention, the flame blocking material is hardened. That is, the hard part of the material has been successfully tested and evaluated as a fireproof seal material for cables and a heat insulating material for steel structures.

In this embodiment, the material is preferably 100 parts by weight of ethylene copolymer, preferably ethylene-ethyl acrylate, 220 parts by weight of aluminum hydroxide, 220 parts by weight of those selected from the group consisting of calcium carbonate and calcium carbonate-magnesium, It consists of 10 parts by weight of paraffin wax lubricant, 11 parts by weight of an elastomer such as EPDM rubber, 11 parts by weight of calcium oxide and 1 part by weight of carbobble. Hereinafter, the preferred form of this substance is referred to as the product P.

In another embodiment of the invention, the material becomes somewhat pliable. In this embodiment the material is 80 parts by weight of ethylene-copolymer, preferably 150 parts by weight of paraffin wax selected from the group consisting of ethylene-ethyl acrylate, 150 parts by weight of aluminum hydroxide, calcium carbonate and calcium carbonate-magnesium. 10 parts by weight of lubricant, 30 parts by weight of an elastomer such as EPDM rubber, 11 parts by weight of calcium oxide, 1 part by weight of a colorant such as carbon black, and 10 parts by weight of a polymer softener such as polyisobutylene. Hereinafter, the preferred form of this material is referred to as product C.

When the flame retardant material of the present invention is used in the manufacture of a refractory cable transition, it is foamed under the influence of strong heat such as combustion heat or radiant heat due to aluminum hydroxide present among them, so that the material is smoke, warm gas generated along the transition. And the penetration of flame. At the combustion temperature of the organic component, i.e., in the combustion state, as described above, the flame barrier material of the present invention forms a strong foam layer having good thermal insulation and high thermal stability. That is, it withstands heat of at least 1100 ° C.

The foam layer provides efficient thermal insulation and mechanical insulation to particles or water objects coated with the flame barrier material of the present invention. Prior to combustion, the material of the present invention is elastic and very resistant to vibrations and mechanical loads.

In addition, the present invention is also defined as a composition for coating or painting the object to be protected from water. Thus, they are present in devices coated or painted with alkyd, polyurethane, vinyl acetate or acrylate as a suspension of micromaterials. On the other hand, the present invention also relates to a method for producing the flame retardant material, the method is a continuous form by mixing these components, drying at an environmental temperature and thereby discharging the mixture at a melting temperature of about 150-200 ℃ To form a effluent and to subdivide the effluent. The material of the present invention was treated using conventional devices such as eviction machines and molding machines. The continuous product, such as yarn, is cut into smaller lengths or volumes and temporarily stored. These finely divided extracts are evicted at about 150 ° C. to produce a coating of the product or the object to be protected from fire, or use them as an insulator. Moreover, the material of the present invention is used as a coating for cables that are easily displaced and exposed or for cables in walls. In testing the flame-retardant material of the present invention used as fire protection material of the cable, the material resisted fire for 180 minutes in the class combustion test (the test was stopped in this state). Only combustion infiltrated or decomposed. The known PVC material for comparison was subjected to the same rapid combustion test, which lasted about 60 minutes, during which time the PVC material was completely decomposed and released harmful chlorine gas. In addition, the materials of the present invention are mixed with their components in powder form to yield a reduced mixture.

The dry mixture according to the above results is evicted at approximately 130 ° C. using a double screw ejector. The extract is then partially cooled and fed to the porous plate to cut into granules at the outlet. The particles are temporarily stored at room temperature. The particles are then used as insulating means or gradually heated up to approximately 150 ° C. and migrate through the ejector to the conduit. The evacuation conduit is equipped with reinforcing means such as metallized yarn or coatings, optionally an outer protective film of plastic material. In particular, the conduit of flame retardants reinforced in this way is useful as a flame retardant shell for electrical cables. In the burned state, the reinforcement conduit forms a strong foam layer having good thermal insulation and high thermal stability. The foam layer imparts thermal insulation and mechanical insulation to the mounted cable. On the other hand, the second floor is supported by the reinforcement gating. According to an embodiment of the flame retardant material of the present invention made in the form of an electrical cable protection conduit, the following components in powder form were mixed at about 30 ° C. 80 parts by weight of ethylene-ethyl acrylate copolymer, 30 parts by weight of synthetic rubber such as EPPM rubber, 10 parts by weight of polyisobutylene, 10 parts by weight of paraffin wax, 11 parts by weight of calcium oxide, 1 part by weight of carbon black, 150 parts by weight of aluminum hydroxide And 150 parts by weight of calcium carbonate, and the resultant dry mixture was then fed through a double screw extractor at 130 ° C., and the extract was fed to the porous plate under partial cooling conditions to cut into particles in the outlet.

The resulting particles are expelled in the form of conduits, if necessary, either stored at room temperature for later use or sent directly to the extractor while gradually heating to approximately 150 ° C. The evacuation conduit is equipped with a reinforced conduit coated with an external protective agent such as polyvinyl chloride. Polymeric matrix materials, such as ethylene-ethyl acrylate copolymers and synthetic rubber, constitute the elastomeric component of the conduit, the relative amounts of these two components being dependent on the desired modulus of elasticity relative to the amount of filler material to be absorbed in the polymerization mixture. Adjusted. In the process of mixing the filler material, polyisobutylene is added to the polymerization mixture as an adjuvant and paraffin wax is added as a lubricant to yield a mixture with sufficient flexibility in preparation. A proper amount of calcium oxide is added as a desiccant to absorb moisture in the mixture and to reduce the risk of pore effects when the polymer and various additives are mixed. In addition, calcium oxide provides a more uniform material. Carbon black is used as a colorant. Also. Prevents oxidation When the material of the present invention is in the combustion state, aluminum hydroxide and calcium carbonate yield a non-combusting porous material and impart the correct density to the foam generated during combustion by interaction between the additives. These foams are converted to strong foaming organic and inorganic layers with good thermal insulation and high thermal stability.

The conduit-type protective products of the present invention exhibit good mechanical protection under normal conditions of use and do not produce halogen gas or detectable smoke upon combustion. Except for organic materials, the protective conduits of the present invention do not burn easily and form thermally stable, ceramic-like foamed organic and inorganic foamed layers with good thermal insulation at high temperatures. It may also be replaced for reinforcement means such as metallization or other conventional materials. Under combustion conditions, chemical reactions cause moisture to occur, which prevents exotherm as described above. In addition, the materials of the present invention have a low heat of combustion, approximately 10 MJ / kg.

The protective conduits of the present invention are manufactured using standard equipment and are relatively economical because they use very useful raw materials.

Representative materials of the present invention are those having the following characteristics.

Tensile Sensitivity (MPa) 10.3 6.9

Elongation at break (%) 7 23

Density, Original Material (kg, / m ³ ) 1840 1640

Density, tar coat (kg / m ³ ) 490 330

Incandescent loss / 1000 ℃ / hour, (weight) 50 56

Smoke density occurrence Arapahou (wt%) 0.5 0.5

Oxygen index (% O ₂₎ 〉 37〉 30

Combustion Energy (MJ / kg) 9 12

Energy consumption rate 200-300 ℃, (MJ / kg) 0.43 0.38

Thermal conductivity

Original substance -20 ℃, (W / m ° K) 0.69-

Tar material 20 ℃, (W / m ° K) 0.07-

Tar material -20-1000 ° C (W / m ° K) 0.06 0.06

Heat resistance

Sheet-9.2mm, (2K / W) 0.0133-

Tarpaulin Sheet -9.2mm, (2K / W) 0.244-

Volume expansion at 200-300 ° (vol.%) 100 200

Electric Volume Resistance (Ohm-cm) 2.7-1.0 "2.7-10"

Halogen Content (wt%) 0 0

Excellent waterproofness

Good oil resistance

Filler weight (% by weight) 79 70

In addition, the refractory experiment of the present invention, as follows. Build a brick cabinet or furnace 6 feet long, 5 feet wide and 4 feet high. Draft slots are installed in the cabinet floor and the heat source is a huge propane combustor installed in the cabinet floor and in the center. In addition, steel cables are horizontally mounted in the center of the cabinet. The experimental sample is placed on a ladder running through a 6-foot cabinet. Preheat cabinets or furnaces to control moisture in bricks and cabinets to prevent artificial cooling by moisture. The cabinet is then cooled for a time sufficient to leave the sample cable protected with the thermal insulation of the invention and to connect the 110 volt power line and thermocouple. During the test, thermocouples are used to measure the flame / fire temperature at four selected locations of combustion, providing continuous temperature records. The average temperature of the cabinet is maintained at about 2000 ° F by controlling propane fuel injected into the cabinet. The temperature in the cabinet reaches 200 ° F within about 2-4 minutes from the fuel ignition time and the actual test start time.

In accordance with the test, temperature (by recording), circuit preservation of each individual conductor by a 110 volt power source, and elapsed time from ignition and fuel injection are indicated. If the short circuit is 1 or more, the experiment ends and the timer stops automatically. The time elapsed by complete circuit preservation is an important result. The experiments were conducted at an ambient temperature of 90 ° F. and 50-60% relative humidity with varying wind speeds of less than 15 mph. The test sample is a three conductor (0.5 cm ² ) 12 AWG Flex-Flame BU cable loosely enclosed with a tube of the present material. The first experiment lasted 18½, while the second experiment lasted 20 ms. The experimental results were in good agreement and the preliminary time of 15 minutes had elapsed as the source of circuit conservation. In addition, experiments with cables of a larger size, such as 3 × 16 mm ² , protected with the present invention were obtained in the same manner, yielding good results as indicated by the circuit retention time of 16 minutes or more. For a similar second fire test, a cabinet or furnace 5 m long, 4 m wide and 1 m high was constructed.

A fuel pit, such as the air inlet of the cabinet wall, is installed at the bottom of the cabinet. A cable sample protected with the present material is wrapped in a steel beam and placed on top of the cabinet to support the middle of the steel beam so that it is not bent. The fuel used at the beginning of the experiment is a mixture of diesel fuel and gasoline. After that, only pure diesel fuel was used. The temperature in the cabinet rose to 1800 ° F after 1 minute of ignition and to 2000 ° F after 5 minutes of ignition. The experimental cable sample is a 2 × 2.5 mm ² Bu cable protected with light of the present material. The Bu cable consists of seven tinned copper wires wound with mica tape, insulated with EPDM and coated with a halogen-free vamac base elastomer. Circuit preservation times for the tested samples are 14.23, 14.41, 16.58 and 16.58 minutes, which is 6½-8½ minutes long using inorganic insulated cables. In addition, the present invention was successfully tested by the IEEE645-1978 test (IEEE standard cable fire stopping condition test). In this experiment, the foamed, sintered and formed material of this invention was completely fire resistant, smoke tightly penetrated and burned for over 180 minutes.

Since the fire resistance of the material of the present invention is reliable, the material is often used as a heat insulating material for steel structures. Steel tubes are insulated with known refractory insulating materials containing inorganic fiber mats, ceramic fiber mats, gypsum, magnesium-oxychloride cement, mica-portland cement, foam cladding and foam paint. Similar steel tubes and H-beams are also insulated with the present invention.

The insulated steel tube and H-beam are contacted with ISO to bring the hydrocarbon fire time-temperature up to 1100 ° C. and 180 minutes. As a result, the material of the present invention, 2.5 and 9 mm thick, did not split, and formed a good thermally insulating sintered tar that maintained its mechanical strength and did not degrade even after 2 hours of the experiment. However, other test materials split and melted.

Steel beams insulated with the material are subjected to H-60 testing. As mentioned, the present invention, when used as an insulating material, is of great importance for protecting electrical cables from fire. The following studies were performed to characterize changes in the material of the present invention at different temperature conditions. Three samples, namely the abovementioned (1) product P; (2) product C; (3) The product A was studied and the substance of this invention which consists of another copolymer of the same class as a component. Like products P and C, product A is a composition comprising a densely packed polymer whose main components are ethylene copolymers, isotium carbonate (CaCO ₃ ) and aluminum hydroxide (Al (OH) ₃ ). In the first part of the study, thermogravimetric, TG and other thermal analyzes, DTA, were performed using a METTLER automatic recording thermal analyzer. In DTA measurement, Al ₂ O ₃ calcined at 1300 ° C was used as a reference material. The flow rate of the inlet gas, ie nitrogen or oxygen, was adjusted to 5 l / hour.

The gas was dried on a silica gel column prior to introduction into the furnace. A sheet-like sample of 3 mm thickness was cut into a disc of 3 mm in diameter and weighed. Approximately 60 mg of 2 discs are placed in a platinum crucible on one side of a PtRh 10% -Pt thermocouple. Another crucible is filled with an Al ₂ O ₃ reference material. The heating rate is automatically adjusted to 25 ° C / min. At the same time, TGIDTA and temperature curves are recorded at a chart speed of 12 inches / minute. Dissolved gases dissipated during thermal analysis are analyzed by mass spectrometer. Emission gas is collected using a glass extraction sample (250 ml) with a taperon stopcock and cylindrical bulkhead (Supelco Inc. Bellefonate, PA). These glass spheres, when the stopcock is opened, are connected to the gas outlet of the METTLER DTA apparatus at the temperature change supported in Table 1 below, and the discharge gas is diluted with nitrogen or oxygen at a flow rate of 5 l / hour through the glass sphere . When the upper limit temperature of the indicated temperature range is reached, the stopcock is closed and the glass sphere is disconnected from the DTA system. 5 ml of gas sample is recovered from the glass sphere through a septum of a 5 ml sample extraction precision syringe attached with a mini nut valve (Control AJ, Sürich) and introduced into a storage source of a pre-vacuum heated mass spectrometer. Opening the MV 38 valve (A.I. Scientific IltiDay, Harlow, Equus) immediately introduces a spectra as the continuous gas is introduced from the reservoir to the mass spectrometer source. Dual-focused A.I.MS 30 mass spectrometer by electron-impact ionization is used. The spectrometer temperature is 150 ° C. and the pressure changes to 3.10 ⁻⁶ −1.10 ⁻⁵ Torr. The electron energy is 70 eV and the acceleration voltage is 4 kV. Record the spectra on a Brian's Surthern Series 10-4306 UV oscilloscope using a scan rate of 30 seconds / decade. From each mass spectrum a different collector electrode sensitivity is obtained and the corresponding spectrum is reduced.

TABLE 1

Emission gas analysis by mass spectrometer

Analyze wax material condenses on the outlet tube of the furnace: The mass spectrum of the material appeared as polyethylene.

White smoke appeared in the gas collection port.

Thermal stability tests of the products P, C and A were carried out using the system shown systematically in FIG. Three samples (Products P, C and A) were simultaneously heat treated for better comparison. Each sample is supported by a stainless steel plate (6 × 6 × 1 mm). After treatment, each sample is cooled to room temperature. Thermal stability test is as follows.

(1) Fast heating rate in nitrogen-three samples were introduced directly into the heating section of the furnace;

(2) fast heating rate in the atmosphere-the same conditions;

(3) Slow heating rate in nitrogen-Three samples are introduced by heating to the center of the furnace at room temperature.

The fast heating rate for each experiment is recorded in ° C / sec and the slow heating rate is recorded for ° C / 60 sec. The temperature increase is measured using a Cromel / Alumel thermocouple under the sample support. It is important to heat it radially. This means that the temperature of the sample surface can be higher than the temperature of the sample itself. The weight gain for each sample is measured.

The experimental results are as follows. The sample temperature record under the flowing nitrogen atmosphere is shown in FIG. Disassembly occurs in three stages. The first step begins at about 245 ° C. (290 ° C. for Product A) and is completed with a strong endothermic effect. At this stage A1 (OH) 3 decomposition takes place and water is lost. The second stage starts at 415 ° C. and is completed with little endothermic effect. This step ends at 560 ° C. On the other hand, weight loss occurs due to volatilization of polyethylene. The vapor is delivered by the nitrogen stream and condensed in the gas outlet pipe. Condensates were identified as low molecular weight polyethylene by IR and mass spectrometry. The final step starts at 730 ° C and ends at 945-955 ° C. Likewise, the heat absorbing effect is completed. In this step, weight loss occurs due to decomposition of CaCO ₃ by removal of CO ₂ . The sample temperature record calculated under the fluid oxygen atmosphere is shown in FIG. Under these conditions, weight loss occurred only in two stages. The first step starts at about 230 ° C. and ends at 380 ° C. (440 ° C. for Product A). This weight loss under oxygen atmosphere corresponds to stage 1 and the summation thereof under nitrogen atmosphere and is decomposed at the same time and the polyethylene burns. The second step starts at 730 ° C. and is completed with an endothermic effect. This is similar to step 3 calculated under nitrogen atmosphere. The decomposition of CaCO ₃ occurs. A summary of the TG measurements is shown in Table 2.

TABLE 2

Thermal degradation of the sample

The DTA thermograms calculated under the fluid nitrogen atmosphere are shown in FIG. The most important thermal effects are described next. Due to the secondary transition of the plastic material, an endothermic effect relaxed at about 100 ° C is observed. This is due to a more pronounced endothermic peak at approximately 352 ° C. Al (OH) ₃ is decomposed and moisture is lost. Only product P and C samples at 415-455 ° C. show a crack peak, due to the melting point transition of polyethylene. All samples show some exotherm at 450-500 ° C. due to evaporation of polyethylene. The thermal effect of 730-940 ° C is CO ₂ formation by CaCO ₃ decomposition. The DTA temperature record produced in the fluid oxygen atmosphere (FIG. 5) shows the same shape as in nitrogen except steps at 250-400 ° C. At this temperature two phenomena occur at the same time: the endothermic dehydrates Al (OH) ₃ and burns the plastic material due to the strong exothermic effect that disrupts the linearity of the heating. The thermal effects developed during the DTA are shown in Table 3 below.

TABLE 3

Properties of Sample DTA

* This exothermic effect occurs during the exothermic action of Al (OH) ₃ decomposition.

Table 1 shows the results obtained by quantitative analysis of the emission gas. CaCO ₃ at 700 ° C. is a uniform crystalline phase for product P and is also a major component for products C and A. Almost no additional diffraction lines were observed in products C and A with very small peak intensities.

This indeterminate rotation line is as follows.

Product-2.40Å 2.40Å 1.70Å

Product 2.89Å-2.04Å-

At this temperature, thermal decomposition of Al ₂ O ₃ , 3H ₂ O by γ-alumina (AlOOH) and Al ₂ O ₃ occurs.

Since no line is observed on the diffraction table, the aluminum-based phase will be amorphous. At 1200 ° C., the observed phases according to the fast heating rate in the atmosphere are as follows.

Product P CaCO ₃ Main Phase

CaO, Al ₂ O

3CaO, Al ₂ O

Product C CaCO ₃ Main Phase

CaO, Al ₂ O

3CaO, Al ₂ O

Product A CaCO ₃ Main Phase

3CaO, Al ₂ O ₃

12CaO, 7Al ₂ O ₃

This means that the pyrolysis of CaCO ₃ was not completed due to the high heating rate. This results in low heat transfer to the material. At 1100 ° C., the following phase is observed with slow heating rate and 12 hours annealing.

Product P 12CaO, 7Al ₂ O ₃ Main Phase

CaO, Al ₂ O ₃

Product C 12CaO, 7Al ₂ O ₃ Main Phase

CaO, Al ₂ O ₃

Product A CaO, Al ₂ O ₃ Main Phase

12CaO, 7Al ₂ O ₃

AlOOH trail

CaCO ₃ trail

Morphologically, the three samples are distinctly different. Products P and C are laminated and product A is isotropic. The non-lamination structure of the product relates to the fact that the product will be made by direct casting of the same mixture. The lamination structure of products P and C is that the side emission of the organic phase was observed below 400 ° C. Products P and C have good protective foaming properties. At elevated temperatures (above 800 ° C), the three products are distinguished by their inorganic nature.

Al ₂ O ₃ is calculated by the decomposition of Al ₂ O ₃ , 3H ₂ O, and reacts with CaO calculated by the thermal decomposition of CaCO ₃ . The rate of mineralization (formation of CaO-Al ₂ O ₃ compounds) is higher for products P and C than for product A. The difference is caused by raw material properties and their degree of fire resistance and particle size.

Claims (20)

A flame barrier material comprising 60-100 parts by weight of an ethylene copolymer matrix, 50-450 parts by weight of aluminum hydroxide and 150-600 parts by weight of a member selected from the constituents of calcium carbonate and calcium carbonate-magnesium. In addition to the material of claim 1, the flame barrier material further comprises 11-30 parts by weight of an elastomer, 0-10 parts by weight of a polymer softener, 8-15 parts by weight of a lubricant, 8-15 parts by weight of calcium oxide, and 1 part by weight of a coloring agent. 3. The fire barrier of claim 2, wherein the lubricant is paraffin wax. 3. The flame barrier material of claim 2 wherein said elastomer is comprised of ethylene propene rubber. The flame barrier material of claim 2, wherein the color developer comprises carbon black. In addition to the material of claim 2, the flame barrier material also comprises an antioxidant consisting of about 1.5 parts by weight of polytrimethyldihydroquinoline per 100 parts by weight of the copolymer. The flame barrier material of claim 1 in the form of a coating or painting composition. The method of claim 1, wherein the ethylene copolymer is ethylene-vinyl acetate, ethylene-acrylic acid, ethylene methacrylic acid, ethylene-ethyl acrylate, ethylene-vinylacetate-methacrylic acid, ethylene-isobutyl acrylateethylenemethyl methacryl Flame retardant selected from the group consisting of late and ethylene-vinylacetate-carbon monooxide. The flame barrier material of claim 1 wherein said ethylene copolymer is ethylene-ethyl acrylate. Rigid flame barrier material consisting of 100 parts by weight of ethylene-acrylate, 220 parts by weight of aluminum hydroxide, 220 parts by weight of calcium carbonate, 10 parts by weight of lubricant, 11 parts by weight of elastomer, 11 parts by weight of calcium oxide and 1 part by weight of color developer. Flexible consisting of 80 parts by weight of ethylene-ethyl acrylate, 150 parts by weight of aluminum hydroxide, 150 parts by weight of calcium carbonate, 10 parts by weight of lubricant, 30 parts by weight of elastomer, 1 part by weight of calcium oxide, 10 parts by weight of polymer softener and 1 part by weight of color developer Apply flame blockers. A method of preparing the flame barrier material of claim 1 by mixing the components dried at ambient temperature and extruding these mixtures at a melting temperature of about 150 ° C. to produce a continuous extrudate and repartitioning the continuous extrudate. The ash ash extrudate produced by the method of claim 12. 14. The method of claim 13, wherein the ash extrudate is extruded at about 150 [deg.] C. to a desired shape to produce a fire barrier coating on the article for protection against fire. 80-100 parts by weight of ethylene-ethyl acrylate polymer, 150-220 parts by weight of aluminum hydroxide, 150-220 parts by weight of a member selected from calcium carbonate and calcium carbonate-magnesium, 11-30 parts by weight of elastomer, softener 0-10 A flame barrier material in the form of a conduit for protecting an electric cable, comprising by weight part, 10 parts by weight of lubricant, 11 parts by weight of calcium oxide, and 1 part by weight of a coloring agent. The ingredients are mixed in powder form to form a crumb mixture at about 30 ° C. and the mixture is extruded at about 130 ° C. to cool the resulting extrudate and subdivided into granules for storage at ambient temperature to obtain the flame barrier material of claim 2. How to manufacture. A method of preparing a flame barrier material in the form of a tube by extruding the granules prepared by the method of claim 16 at 120 ° C. An extruded flame barrier material in the form of a tube produced by the method of claim 17. 19. A flame barrier material in the form of a tube which further comprises an outer steel braiding and an outer protective coating in addition to the material of claim 18. 20. The extruded flame barrier material of claim 19 wherein the outer protective coating is a plastic material.

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