KR100388638B1 - A composition for flame retarding polyolefin foams with ground tire rubber and its manufacturing method - Google Patents

Abstract

The present invention relates to a flame-retardant polyolefin foam composition using a tire powder and a method of manufacturing the same, and more particularly to blending polyolefin-based, rubber-based resins and tire powder (Ground tire rubber, hereinafter referred to as GTR), and thus flame retardant (non-machined) ), A composition made by mixing a blowing agent, a crosslinking agent, and other additives, which can efficiently recycle GTR and, in some cases, eliminates the use of halogen compounds that have been used to impart and enhance flame retardancy. It is possible to manufacture products with excellent mechanical properties. When applied to a wide range of fields such as various building materials, automobile parts, sporting goods, and other industrial products by extrusion or injection molding, it is very useful because it has environmental friendliness, stability, and flame retardancy. Improved composition flame retardant polyolefin foam that can be used It relates to a composition and method for making him.

Description

A flame retarding polyolefin foams with ground tire rubber and its manufacturing method

The present invention relates to a flame-retardant polyolefin foam composition using a tire powder and a method of manufacturing the same, and more particularly to blending polyolefin-based, rubber-based resins and tire powder (Ground tire rubber, hereinafter referred to as GTR), and thus flame retardant (non-machined) ), A composition made by mixing a blowing agent, a crosslinking agent, and other additives, which can efficiently recycle GTR and, in some cases, eliminates the use of halogen compounds that have been used to impart and enhance flame retardancy. It is possible to manufacture products with excellent mechanical properties. When applied to a wide range of fields such as various building materials, automobile parts, sporting goods, and other industrial products by extrusion or injection molding, it is very useful because it has environmental friendliness, stability, and flame retardancy. Improved composition flame retardant polyolefin foam that can be used It relates to a composition and method for making him.

Existing polyolefin foam is a molding composition that is widely used in construction, construction, automobiles, sporting goods, and other fields. Flame retardancy is required due to various regulations in the world and domestically based on environment and safety. In this case, by using halogen-based compounds (resin and flame retardant) to impart flame retardancy and increase in toxicity due to the release of toxic and corrosive gases such as hydrogen halide, the scope of application is being reduced due to the low flame retardancy.

Known flame retardant polyolefin foams, in the case of flame retardant foams of VO grade according to ASTM-D-2863 or class "O" according to BS 476, the composition of which only blends nitrile rubber (NBR) and polyvinyl chloride (PVC) It has been suggested that the resin is prepared by adding a flame retardant and other additives. (US Pat. No. 5,720,33, Ronald S. Lenox, Lancaster, Pa .; Kim S. Boyd, Quincy, Mass .; William S. Vought, Jr.) , Landisville, Pa, Feb. 16, 1993), (US Patent No. 4245055, Wayne E. Smith, Washington Boro, Pa, Jan. 13, 1981), (US Patent No. 3993607, David M. Florence, Lancaster , Pa, Nov. 23, 1976).

Although such a flame retardant composition is slightly different depending on its specification, one of the compositions is representatively exemplified by 15 to 85 parts by weight of polyvinyl chloride or 1 to 200 parts by weight, plasticizer based on 100 parts by weight of nitrile rubber. 10 to 100 parts by weight, flame retardant 100 parts by weight (5 to 75 parts by weight of iron oxide) / 10 to 85 parts by weight of lubricant, 0.1 to 10 parts by weight of stabilizer, 10 to 20 parts by weight of blowing agent, 2.5 parts by weight of sulfur, zinc oxide (ZnO ) 5 parts by weight, 2.1 parts by weight of stearic acid, 0.8 parts by weight of benzothial disulfides (MBTS), and 0.4 parts by weight of tetramethylthinram monosulfide (Monex).

However, such a conventional polyolefin foam composition has a certain degree of flame retardancy, but other physical properties are relatively poor, and there is a need to improve the product to a better physical property. In particular, as described above, a halogen-based flame retardant is used. There was much room for improvement due to the harmfulness of humans and the environmental friendliness of halogen compounds.

Therefore, in the present invention, in order to improve the disadvantages of the conventional flame retardant polyolefin foam composition, nitrile rubber is used as it is in the conventional resin composition, but unlike the conventional ethylene-propylene copolymer (EPDM) and tire powder (GTR, Ground tire rubber) and polyethylene (PE), and in some cases, some halogen-containing compositions use existing nitrile rubber and polyvinyl chloride as they are, but unlike conventional combinations of GTR and chlorinated polyethylene (CPE) New flame retardant polyolefins with improved flame retardant and other additives, which are more environmentally friendly and more flame retardant and mechanically superior to conventional compositions. It is an object to provide a foam composition.

1 is an electron microscope (SEM) photograph confirming the cell structure (A), the additive dispersion degree (B) and the surface state (C) with respect to the foam composition (sample 1) according to Example 1 of the present invention.

2 is an electron microscope (SEM) photograph confirming the cell structure (A) and the additive dispersion degree (B) with respect to the foam composition (sample 2) according to Example 1 of the present invention.

3 is an electron microscope (SEM) photograph confirming the cell structure (A), the additive dispersion degree (B), and the surface state (C) of the foam composition (sample 6) according to Example 2 of the present invention.

4 is an electron microscope (SEM) photograph confirming the cell structure (A), the additive dispersion degree (B), and the surface state (C) of the foam composition (sample 15) according to Example 2 of the present invention.

Figure 5 is an electron microscope (SEM) photograph confirming the cell structure (A) and the additive dispersion degree (B) for the conventional foam.

The present invention relates to a flame retardant polyolefin foam composition comprising essentially nitrile rubber as a resin component and comprising at least one additive of a flame retardant, a crosslinking agent, a plasticizer, a foaming agent, a filler, a moisture absorbent, an anti-aging agent, a lubricant, and a stabilizer as a common additive. It uses tire rubber (GTR) as an essential resin component, and selects components such as nitrile rubber, polyvinyl chloride, and chlorinated polyethylene, and natural rubber, styrene-butadiene rubber, ethylene-propylene copolymer, and polyethylene. It is possible to manufacture a product having excellent physical properties without using a halogen compound, in particular, and characterized by a flame retardant polyolefin foam composition composed by adding a predetermined flame retardant and a conventional additive thereto.

The present invention is described in detail as follows.

In the flame retardant polyolefin foam composition containing nitrile rubber as a resin component and at least one additive of a flame retardant, a crosslinking agent, a plasticizer, a foaming agent, a filler, a moisture absorbent, an anti-aging agent, a lubricant, and a stabilizer as a conventional additive, The component is composed of 50 to 100 parts by weight of nitrile rubber, 10 to 30 parts by weight of polyvinyl chloride or chlorinated polyethylene, 0 to 100 parts by weight of ethylene-propylene copolymer, and 1 to 50 parts by weight of GTR. (OH) ₃ 10 to 100 parts by weight, Mg (OH) ₂ 30 to 90 parts by weight, 5 to 50 parts by weight of Sb ₂ O ₃ and 5 to 20 parts by weight of ocher. It is contained in 1 to 1.8 parts by weight, characterized in that the usual additives are contained.

The present invention also relates to a flame retardant polyolefin foam composition containing nitrile rubber as a resin component and comprising a flame retardant, a crosslinking agent, a plasticizer, a foaming agent, a filler, a moisture absorbent, an anti-aging agent, a lubricant, and a stabilizer as a conventional additive, wherein the resin component is nitrile. Rubber and natural rubber, styrene rubber and ethylene-propylene copolymer of 50 to 100 parts by weight of one or more components, 0 to 80 parts by weight polyethylene and 1 to 50 parts by weight of GTR, the flame retardant added thereto is Al (OH) ₃ 10 to 100 parts by weight, Mg (OH) ₂ 30 to 90 parts by weight, Sb ₂ O ₃ 5 to 50 parts by weight and loess 5 to 20 parts by weight of flame retardant to 1 part by weight of the resin component 1 to 1.8 It is contained in parts by weight, characterized in that the usual additives are contained.

Such a foam composition according to the present invention contains 0-50 parts by weight of a plasticizer, 0-15 parts by weight of a stabilizer, 10-40 parts by weight of a foaming agent, etc., as a conventional additive in a mixture of the above-mentioned optionally composed resin, GTR and flame retardant. The composition may be prepared by first mixing at 110 to 120 ° C., adding 0 to 5 parts by weight of the crosslinking agent and 0 to 3 parts by weight of the crosslinking accelerator, and mixing the mixture at 60 to 70 ° C. for the second time.

Referring to the present invention in more detail as follows.

Specific examples of component composition of the composition of the present invention, the resin component is 50 to 100 parts by weight of nitrile rubber, 10 to 30 parts by weight of polyvinyl chloride or chlorinated polyethylene, 0 to 100 parts by weight of ethylene-propylene copolymer and It is composed of 1 to 50 parts by weight of GTR, and the flame retardant added thereto is 10 to 100 parts by weight of Al (OH) ₃ , 30 to 90 parts by weight of Mg (OH) ₂ , 5 to 50 parts by weight of Sb ₂ O ₃ , and yellow soil 5 It is composed of ~ 20 parts by weight, but contains 1 to 1.8 parts by weight of flame retardant based on 1 part by weight of the resin component, 0 to 50 parts by weight of plasticizer, 0 to 15 parts by weight of stabilizer, 0 to 5 parts by weight of crosslinking agent. 2-mercap benzothiazole (M), di-benzothiadyl disulfide (DM) and Zn-dimethyl-dithiocarbamate (PZ) are 0 to 3 parts by weight, respectively, as a crosslinking accelerator, 40 parts by weight, 0 to 3 parts by weight of foaming aid, 0 to 10 parts by weight of heat transfer accelerator, 0 to 5 parts by weight of external mold release agent, internal Brother 0-4 can be manufactured to include parts by weight, and 0 to 10 parts by weight of a moisture absorbent, an antioxidant 0 to 10 parts by weight of filler 0 - 10 parts by weight.

In addition, a specific example of a foam-friendly composition of the composition without using a chlorinated compound in a similar composition, the resin component is at least one component of nitrile rubber, natural rubber, styrene rubber and ethylene-propylene copolymer 50-100 It is comprised by weight part, 0-80 weight part of polyethylene, and 1-50 weight part of GTR, and other flame retardant and a normal additive can be comprised by the same structure as the said composition.

According to the present invention, in order to prepare a foam composition as described above, after adding the flame retardant component composition to the resin composition, the plasticizer 0-50 parts by weight, stabilizer 0-15 parts by weight, foaming agent 10-40 weight Part is added, followed by primary mixing at 110 to 120 ° C., where 0 to 5 parts by weight of the crosslinking agent and 2-melcap benzothiazole (M) and dibenzothiadyl disulfide (DM) are used as the crosslinking accelerator. And 0 to 3 parts by weight of Zn-dimethyl dioxycarbamate (PZ) may be added, and the mixture may be secondly mixed at 60 to 70 ° C for extrusion or injection. In addition, for improving the physical properties, for example, coumarone resin (coumarone) resin can be used additionally 0 to 6 parts by weight.

In the present invention, the resin composition is selected from nitrile rubber, natural rubber, styrene rubber, ethylene-propylene copolymer, polyvinyl chloride, chlorinated polyethylene, and polyethylene, and has never been used before. It is composed of using as an essential component, in particular, GTR is preferably used in consideration of recycling in the present invention is made of powder by crushing the car tires, such as ordinary cars, trucks, buses, chemical stability is high and atmospheric Its low content of contaminants allows it to be used as a good filler in polyolefin blend materials.

According to the present invention, since GTR has a crosslinked structure and is high in carbon black content and strong, it can be well harmonized with the plastic used therewith, and also has high UV resistance and high chemical stability, such as activated carbon contained in itself. Since it is suitable for this particle-reinforced composite material, it shows a very useful effect. Furthermore, in the combustion state, char is easily formed, thereby forming a heat insulation layer on the surface and blocking the combustion propagation into the inside. In addition, since the GTR is added in a powder form, it is easy to disperse in the matrix resin, and the particle size greatly affects the mechanical properties of the composite, and as the size increases, problems in interfacial adhesion occur. Tensile properties will be degraded. Therefore, in consideration of the above, the GTR used in the present invention is preferably used having a particle size of 0.5mm or less, but the present invention does not place any particular limitation on its size.

On the other hand, the present invention is characterized by using ocher as flame retardant component in addition to the above GTR, the ocher used in the present invention is preferably kaolin mineral (kaolin; Al ₂ O ₃ · 2SiO ₂ · nH ₂ O) Montmorillonite (Al ₂ O ₃ · 4SiO ₂ · 6H ₂ O), pyrophyllite (Al ₂ O ₃ · 4SiO ₂ · H ₂ O), illite (KAl ₂ (OH) ₂ (AlSi) ₃ (O, OH) ₁₀ ]) and talc (3MgO. 4SiO ₂ .H ₂ O). Depending on the type of loess, they can intercalate organic materials and have an extremely high specific surface area of about 800 m ² / g, which acts as an absorbent and can serve as an efficient filler due to their high surface adsorption. do.

On the other hand, the composition of the GTR used in the present invention can be used that generally shows a chemical composition as shown in Table 1.

Analysis item PC ^a PC + LT ^b TB ^c Rubber powder Rubber powder Rubber powder Type of rubber polymer Compounding ratio ^d (%) NR 20 40 70 SBR 80 45 20 BR - 15 10

In Table 1, a denotes a passenger car tire, b denotes a light truck tire, c denotes a truck and a bus tire, d denotes a value obtained by gas chromatographic analysis, e denotes a value obtained by sodium sulfite method, and f denotes a nitrate analysis method. The figures are shown.

In general, tires are mainly composed of natural rubber (NB), styrene-butadiene rubber (SBR) and butadiene rubber (BR). The composition is determined as shown in Table 2.

division car truck Tread SBR-BR NR ^a -BR or SBR-BR belt NR NR Caucas NR-SBR-BR NR-BR Side wall (black) NR-SBR or NR-BR NR-BR Side wall (bag) NR-SBR-EPDM-IIR ^b - Lina NR-SBR or NR-SBR-IIR NR-IIR

In Table 2, a includes polyisoprene rubber (IR), and b includes butyl halide (IIR) isobutylene-isoprene rubber (IIR).

As described above, in the present invention, mechanical properties and chemistry are achieved by blending GTR at a predetermined ratio with a resin selected from nitrile rubber, natural rubber, styrene rubber, ethylene-propylene copolymer, polyvinyl chloride, chlorinated polyethylene, and polyethylene in a specific composition. In addition to enhancing physical properties such as stability, tires, which have been mostly discarded or inefficiently used and partly recycled, can be recycled very effectively, usefully and fundamentally to maximize economics, and in some cases, to produce eco-friendly products. It is of great significance to be used as a core essential ingredient.

In particular, the present invention maximized flame retardancy by using only inorganic flame retardants (Al (OH) _3, etc.) in consideration of the environment and safety, as well as using two components as well as three or more of the six components as the resin component. In addition, it is possible to contribute to the maximization of physical properties, diversification of the field of application, environmentally friendly product production, etc. while appropriately utilizing the GTR through a predetermined formulation.

In general, halogenated compounds have a flame retardant effect by fundamentally stabilizing radicals generated in a gas phase, and the mechanism is inferred by the following chemical reaction.

HOH + X

HX + R · regeneration reaction (stop of chain reaction)

HX + O ₂ (retardant effect by reducing the concentration of active O and OH and stopping the chain reaction)

XO + M

X ₂ XO · + X · (decomposition upon the effect of blocking the generation of non-combustible gas, O ₂₎

O ₂ + X

In the chemical formula 1, activating radicals such as OH radicals generate heat through a chemical reaction, and the latent heat generated acts as an energy source required for combustion of surrounding flammable materials.

On the other hand, the flame retardant gives a flame retardant effect by reducing the concentration of the active radicals O · and · OH and stopping the chain reaction, as in the above mechanism, the cleavage of the CX bond during combustion is an endothermic reaction to reduce the heat of combustion of the combustible material have. It also has the effect of blocking oxygen by generating incombustible gases during decomposition. Therefore, the actual flame retardant effect is given by HX and reacts and is converted into X radical of low energy source. HX acts as an oxidation catalyst of the combustible material, and the oxidized material is ring-structured, resulting in char, a carbon compound. The carbon compound thus produced serves to help prevent the combustible material from below the combustion zone by blocking oxygen and latent heat.

In the present invention, as a flame retardant, in view of human harmfulness, an inorganic type is used without the halogen system, and aluminum hydroxide, antimony oxide, magnesium hydroxide, and boron-containing compound may be used. Inorganic flame retardants, unlike organic flame retardants, do not volatilize by heat and decompose to release non-combustible gases such as H ₂ O, CO ₂ , SO ₂ , HCl, and are mostly endothermic. In the gas phase, the flammable gas is diluted and the plastic surface is coated to prevent the access of oxygen. At the same time, there is an effect of reducing the generation of plastic cooling and pyrolysis water through the endothermic reaction on the solid phase surface. For example, aluminum hydroxide and magnesium hydroxide produce water after decomposition as follows, whereby a large amount of endotherm is accompanied to impart flame retardancy.

2Al (OH) ₃ Al ₂ O ₃ + 3H ₂ O -298KJ / mol

Mg (OH) ₂ MgO + H ₂ O -328KJ / mol

Antimony oxide has antimony trioxide and antimony pentoxide, and is used as an adjuvant that exhibits a flame retardant synergistic effect of a halogen-containing flame retardant without being used as such. The mechanism is inferred as follows. That is, SbCl ₃ produced in each step reaction below has an effect of lowering the temperature of the plastic through the endothermic reaction, and acts as a radical interceptor like HCl and HBr. Some have suggested that both SbCl ₃ and SbOCl have a flame retardant synergistic effect by lowering the rate of halogen release in the combustion zone, increasing the time to act as a radical interceptor.

In addition, the generated heavy gas surrounds the surface of the solid phase, thereby blocking oxygen access and thus exhibiting a flame retardant effect.

Sb ₂ O ₃ 2SbOCl + H ₂ O

Sb ₄ O ₅ Cl + SbCl ₃ ↑

4Sb ₄ O ₅ Cl ₂ 5Sb ₃ O ₄ Cl + SbCl ₃ ↑

3Sb ₃ O ₄ 4Sb ₂ O ₃ + SbCl ₃ ↑

Sb ₂ O ₃ Sb ₂ O ₃ (I)

In the present invention, as the resin, nitrile rubber, natural rubber, styrene rubber, and ethylene-propylene copolymer are used. Preferably, in the case of nitrile rubber, acrylonitrile-butadiene having an acrylonitrile (AN) content of 28 to 35%. In the case of rubber and styrene rubber, in the case of styrene-butadiene rubber and ethylene-propylene copolymer, the ENB content of 4.5-8 wt% is preferably used as the base resin.

In the present invention, some halogen-containing compositions include polyvinyl chloride (PVC) and chlorinated polyethylene (CPE), which are basic flame retardant resins, and preferably, CPE having a chlorine content of 36 to 42% is blended. It is useful to provide basic flame retardancy of mixed resin itself and to improve compatibility with other olefin resins.

In the present invention, it is preferable to use a particle size of 0.5 mm or less when the GTR is mixed and used to improve properties and recycle the resin.

In the present invention, in order to prepare an environment-friendly composition in consideration of the effect on the environmental surface and processability as a flame retardant, to exclude the use of halogen-based flame retardant, Al (OH) ₃ , Mg (OH) which is preferably an inorganic flame retardant ) _2, Sb ₂ O _3, it is preferred to indicate to the hydrobromic acid zinc (zinc-borate) and the effect of that promote the flame retardancy, while considering the environmental aspect of using the yellow soil. The present invention also includes using all five components or selecting one or more of them as a flame retardant.

In addition, it is preferable to use azodicarbonamides (7000MC, 5000F, 3000F, ADCA), which are azo compounds, as the blowing agent, and to adjust the foamability and temperature which will affect processability and productivity, A foaming aid (trade name Cellex-A) and ZnO can be preferably used as the heat transfer accelerator.

Sulfur is used as the crosslinking agent used in the present invention, and 2-mercapt benzothia is relatively scorched with thiazoles in consideration of vulcanization promoting effect, scorch resistance, aging resistance, activating temperature, dispersibility, and contamination. Sol (M), di-benzothiadyl disulfide (DM) with relatively low scorch, dithioates, and scorch and vulcanized Zn-dimethyl dithiocarbamate (PZ) at an appropriate ratio as described above. It is preferable. In addition, as a stabilizer, a Ba-Zn-based stabilizer is used in consideration of the foaming rate and the effect of obtaining a uniform cell according to the use of a large amount of filler. For example, trade names BZ-806F and BZ-119 are preferably used. Can be used.

It is preferable to use diethylhexyl phthalate (DOP) and paraffin oil (P3 ~ P6) as a plasticizer in consideration of compatibility with the resin, processability, and foamability. It is preferable to use a kind of silitin and CaO, and an anti-aging agent can preferably use 2,2,4-trimethyl-1,2-dihydroquinone (Kumanox RD) in consideration of the effect on vulcanization. The internal release agent is polyethylene wax (LC-102N) as a rubber processing enhancer, stearic acid as an external release agent in consideration of extrudability, and the filler is color imparting and anti-oxidation, reinforcing effect and cost reduction. It is preferable to use carbon black (N550FEF) in consideration of the above.

Method for producing a composition according to the present invention as described above will be described as an example of the present invention through each of the following examples, this embodiment of the present invention is to illustrate the case that is manufactured according to the intended use of the present invention is limited It is not intended that, in the examples, the percentage (%) indicating the content of the composition means% by weight unless otherwise indicated.

The abbreviation of the components used in the examples is NBR is acrylonitrile-butadiene rubber, NR is natural rubber, SBR is styrene-butadiene rubber, EPDM is ethylene-propylene copolymer, PVC is polyvinyl chloride, PE is polyethylene, CPE is Chlorinated polyethylene and GTR shall mean tire rubber and DOP shall mean diethylhexyl phthalate.

Example 1

In the composition of the flame-retardant polyolefin foam filed by the present inventors and a method of manufacturing the same (Korean Patent Application No. 99-47008), the thermal and dynamic behaviors of NBR / PVC and PE blends according to the composition ratio, temperature, and time were observed, According to the morphology of NBR / PVC blends, PVC particles decreased with time, and after 30 minutes, they were dispersed in a particle size of about 0.1 to 0.2 µm. It can be seen that the dispersed phase of, NBR / PE blends showed that no significant phase separation after 10 minutes, NBR / PVC = 1/1, 0.8, 0.6 Wt In the case of%, the compatibility of CPE content is clearly shown. The composition of NBR, EPDM / PVC, CPE, PE / GTR blend is shown based on the characteristics of homogeneous phase within the range of 10 ~ 30 Wt% of CPE. It was investigated in connection with deleted; (limiting oxygen index LOI), observing thermal and kinetic geodongreul with temperature and time, and this foamed (foaming rate, cell structure, surface condition, etc.) and flame retardancy. In particular, halogen-based compounds are excluded in consideration of environmental friendliness, and resins are composed only of NBR and GTR, and in order to control their composition ratio and other additives, and to control the size and drying of GTR particles, and to prevent bubble formation on the surface after foaming The use of an absorbent [silica (sillitin)] and also in consideration of dehydration, deodorization, flame retardant yellow soil was also used, the composition ratio of the resin and additives (particularly flame retardant and absorbent) was carried out.

The composition ratios of the resin components were composed as shown in Table 3, respectively, and the blend was prepared at Rheomixer (HAAKE) without adding crosslinking and crosslinking accelerators at a temperature of 110 to 130 ° C, RPM50 for 20 to 40 minutes, and then crosslinking and crosslinking. With the addition of the accelerator, the temperature is 60-70 ° C., RPM 50, time 5-10 minutes, and the extrusion is carried out within a temperature range of 70-80 ° C., Rs 5, time 1-3 minutes in a minimax molder (Csi-183MMV). Hot-press (Carver) was carried out at a temperature of 160 ~ 250 ℃. In addition, the foaming test investigated the surface condition, foaming rate, cell structure, etc. after foaming, and the flame retardancy test was a LOI (Atlas) test, and the specimen size was 6.5 +/- 0.5mm wide and 2.0 thick according to ASTM-D-2863. Limiting Oxygen Index (LOI) was measured by arbitrarily adjusting the injection amount of oxygen and nitrogen at +/- 0.25mm and length of 7.0 ~ 150mm, and morphology investigation was performed by electron microscope SEM (JEOL JSM-840A). The fracture surface of the specimen was observed.

As a result, when NBR / PVC / CPE / GTR = 58/17/17/8 wt% as in sample 1, foaming occurred at a temperature range of 160 to 190 ° C, and the time required was about 5 minutes. It was confirmed that the smooth, the cell structure is uniform as a closed cell (cell), and has a foaming ratio of about 150% (about 2.5 times) or more in the radial direction.

In addition, the LOI test showed that the marginal oxygen index was 26.9, which is practically high.

In case of sample 2 composed of NBR / GTR considering environmental friendliness, we wanted to see the effect of the change of the absorbent and flame retardant content on the foamability and flame retardancy. When the other flame retardant content is the same, the content of loess is 10phr, and When the content is 5 phr, foaming occurs at a temperature range of 150 to 160 ° C., and the time required is about 15 minutes, the cell structure is uniform, smoothness without bubbles on the surface, and the foaming rate is about 200 in the radial direction. It was confirmed that three times the foaming occurred in%. In addition, deodorization, dehumidification, and decrease in smoke density were observed according to the use of ocher, and when the GTR particle size was 0.3mm, it was confirmed that the cell structure was uniform compared to 0.5mm. In addition, the LOI test showed that the marginal oxygen index was 26.5, which was also quite high in practical terms. The cell structure (A), additive dispersion degree (B) and surface state (C), which are the results of the composition and the electron microscopic confirmation of the contents, are shown in Table 3 and FIG. 1 (Sample 1) and FIG. 2 (Sample 2). Represented in each. In the following Table 3, the numerical value means 'parts by weight' as the amount of the corresponding ingredient.

Sample Number Composition One 2 Suzy NBR 58 80 PVC 17 CPE 17 GTR 8 20 Flame retardant Al (OH) ₃ 20 50 Mg (OH) ₂ 60 40 Sb ₂ O ₃ 10 20 Chlorinated Paraffin 10 ocher 20 External release agent Stearic acid 2.5 2.5 Absorbent sillitin 5 Internal release agent PE wax 4 4 PVC stabilizer Ba-Zn system 15 Plasticizer DOP 30 35 Anti-aging 2,2,4-trimethyl dihydroquinoline 2.5 2.5 Filler Carbon black 5 3 Crosslinking agent sulfur 3 2 Crosslinking accelerator M One One DM One One PZ One One blowing agent Azodicarbonamide (Cellcom-AC system) 18 18 Foaming aid Urea system (Celex-A) 1.5 Heat transfer accelerator ZnO 4

Example 2

As a result of Example 1, the composition and processing conditions for obtaining a foam having a foaming ratio of about 2.5 times or more in the radial direction and a uniform cell structure and a smooth surface could be identified. Considering the prevention of bubble generation on the surface and controlling the content of the flame retardant, hygroscopic, plasticizer and other additives compared to the resin. In addition, in the case of the composition consisting of only EPDM / GTR, and also focused on the foamability (foaming rate, surface, cell structure, elastic modulus) and flame retardancy to control the additives relative to the resin, in particular the content of the crosslinking agent and crosslinking accelerator. Composition ratios related to these are shown in Table 4 below, and blend, extrusion, crosslinking and foaming, and foaming, flame retardancy, and morphology investigation were performed in the same manner as in Sample 1.

As a result, in the case of the foam composed of NBR / GTR, foaming occurs at a temperature range of 156 to 170 ° C, and the time required is about 6 to 12 minutes, the surface is smooth, and the cell structure is a closed cell. It was confirmed that it was uniform and had a foaming rate of about 150 to 200% (about 2.5 to 3 times) in the radial direction.

In addition, the LOI test result shows that the critical oxygen index is 26.1 ~ 28.9, which is quite high in practical terms. In particular, in some samples, the marginal oxygen index was 28.3 to 28.9, which showed very high flame retardancy of 28 or more.

On the other hand, in the case of the foam composed of EPDM / GTR, foaming occurs at a temperature range of 160 to 210 ° C, and the time required is about 7 to 16 minutes, the surface is smooth, and the cell structure is a closed cell. It was confirmed that it was uniform, had a foaming ratio of about 150 to 200% (about 2.5 to 3 times) in the radial direction, and had an elastic modulus equivalent to that of the NBR-based foam. In addition, the LOI test result showed that the limit oxygen index was about 28.

As a result, a foam composed of NBR and EPDM / GTR was found to have a foaming ratio of 2.5 to 3 times, a smooth surface, a uniform cell structure, and formulation and processing conditions for obtaining a foam having excellent elastic modulus.

Therefore, it was confirmed experimentally that the mixing ratio condition corresponding to the above-described constitution of the present invention is preferable in the mixing under the defined mixing and processing conditions.

And, in the processing conditions for processing into foam using such a composition, the blend was brought to Rheomixer (HAAKE) at a temperature of 110 to 130 ° C., RPM50 for 20 to 40 minutes without addition of a crosslinking accelerator, and then crosslinking and crosslinking. A predetermined amount of accelerator is added and the temperature is 60-70 ° C, RPM 50, time 5-10 minutes, and the extrusion is carried out within a temperature range of 70-80 ° C, Rs 5, time 1-3 minutes in a minimax molder (Csi-183MMV), When foaming was performed at a temperature of 160 to 250 ° C. in a hot press (Carver), foams having excellent foamability and flame retardancy were obtained as described above.

The results are shown in Table 4 and the accompanying drawings, Fig. 3 (Sample 6) and Fig. 4 (Sample 15), respectively, in the same manner as described above. The degree of dispersion of the additives is shown in the accompanying drawings of FIG. 5, which shows better characteristics than those of FIG. 5.

Sample Number Composition 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Suzy NBR 80 80 80 80 80 80 80 80 80 80 EPDM 82 80 80 80 80 GTR 20 20 20 20 20 20 20 20 20 20 18 20 20 20 20 Flame retardant Al (OH) ₃ 70 50 60 70 70 70 70 70 70 70 50 50 40 60 70 Mg (OH) ₂ 40 40 50 40 40 40 40 40 40 35 70 70 50 90 80 Sb ₂ O ₃ 10 10 10 30 10 30 10 20 10 10 10 10 10 10 20 ocher 10 10 10 10 10 10 10 10 10 10 15 10 20 10 10 External release agent Stearic acid 2.5 2.5 2.5 2.5 2.5 3 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 Absorbent sillitin 10 5 10 10 10 10 10 10 10 10 2 One One 10 10 Internal release agent PE wax 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 Plasticizer DOP 40 40 35 35 40 35 35 40 35 30 40 40 40 30 30 Anti-aging 2,2,4-trimethyl dihydroquinoline 2.5 2.5 2.5 2.5 3 3 4 5 6 5 2.5 2.5 2.5 5 5 Filler Carbon black 3 3 3 3 3 3 3 3 3 3 2 2 3 3 3 Crosslinking agent sulfur 1.5 2 2 2 2 2 2 2 2 2 1.25 1.25 2 2 2 Crosslinking accelerator M One One One One One One One One One One One One One One One DM One One One One One One One One One One One One One One One PZ One One One One One One One One One One One One One One One blowing agent Azodicarbonamide (Cellcom-AC system) 18 18 18 18 18 18 18 18 18 18 18 18 18 18 18 Foaming aid Urea system (Celex-A) 1.5 Heat transfer accelerator ZnO 4 4 4 5 5 6 6 7 6 4 4 6 6

Sample number Foot Po Composition water LOI (Limit Oxygen Index) Foaming method Firing degree Effervescent Composition ratio (wt%) 160 → 250 ℃ Foaming temperature / time required (℃ / min) Foaming rate (%) surface Cell structure R / F-R Resin (N / E / G) Flame Retardant (Al / Mg / Sb / Ocher) P / B-A (DOP / AC system) 3 190/8 ′ 200 Good Uniformity 100/130 80/0/20 70/40/10/10 40/18 28.1 4 156-170/10 ' 150-200 〃 〃 100/110 〃 50/40/10/10 〃 26.2 5 〃 〃 〃 〃 100/130 〃 60/50/10/10 35/18 27.5 6 〃 〃 Good (△) 〃 100/150 〃 70/40/30/10 〃 28.6 7 166-172/6 ' 200 Good 〃 100/130 〃 70/40/10/10 40/18 28.2 8 〃 〃 Good (△) 〃 100/150 〃 70/40/30/10 35/18 28.6 9 163-170/8 '50 " 150-200 Good 〃 100/130 〃 70/40/10/10 〃 28.6 10 〃 〃 〃 〃 100/140 〃 70/40/20/10 40/18 28.9 11 165-167 / 11'20 " 150 〃 〃 100/130 〃 70/40/10/10 35/18 28.3 12 170/8 ′ 150-200 〃 〃 100/125 〃 70/35/10/10 30/18 28.6 13 180 to 210 / 8'40 ″ 150 Good (△) 〃 100/145 0/82/18 50/70/10/15 40/18 27.3 14 210 / 7′25 ″ 〃 Good 〃 100/140 0/80/20 50/70/10/10 〃 27 15 180 ~ 210 / 16′32 ″ 200 〃 〃 100/120 〃 40/50/10/20 〃 26.1 16 160 to 185 / 15′30 ″ 〃 〃 〃 100/170 〃 60/90/10/10 30/18 28.3 17 160 to 185 / 12'45 ″ 150-200 〃 〃 100/180 〃 70/80/20/10 〃 28.7

In Table 5, R / FR is the weight ratio of resin / flame retardant, resin (N / E / G) is NBR / EPDM / GTR composition ratio, flame retardant (Al / Mg / Sb / ocher) is Al (OH) ₃ , Mg (OH) ₂ , Sb ₂ O ₃ , use parts by weight of ocher, and P / BA (DOP / 5000F) are expressed in parts by weight of the plasticizer / foaming agent.

As can be seen from the progress of Table 5, in the case of the foam composition according to the present invention, the foaming degree (foaming rate) was at least 150% or more, and the foaming rate was about 200%. In addition, the limiting oxygen index (LOI) was also found to be about 28 or more when the flame retardants were used normally (samples 4, 13, 14, and 15 used relatively few flame retardants), and non-halogen flame retardants were used. At the same time, it showed very excellent properties in flame retardancy.

Example 3

The experiment was carried out in the same manner as in Example 2, but using an adhesive improver as an additive, and the results were as shown in Table 7 below with the composition shown in Table 6 below.

According to this result, in the case of the foam composed of NR, SBR / GTR and NR / SBR / GTR, foaming occurs at a temperature range of 150 to 170 ° C, and the time required is about 20 minutes, the surface is smooth, and the cell structure is It was confirmed that it was uniform as a closed cell and had a foaming rate of about 150 to 200% (about 2.5 to 3 times) in the radial direction. As a result of LOI test, the marginal oxygen index was 28.1 to 31.1, and it was confirmed that the flame retardancy was higher than 28.

In the following Table 6 and Table 7 was written in the manner described above.

Sample Number Composition 20 21 22 23 24 25 26 27 28 Suzy NBR NR 80 80 80 60 60 60 SBR 80 80 80 20 20 20 EPDM GTR 20 20 20 20 20 20 20 20 20 Flame retardant Al (OH) ₃ 90 80 90 90 90 85 90 90 90 Mg (OH) ₂ 60 65 60 60 55 60 60 55 65 Sb ₂ O ₃ 10 10 10 10 10 10 10 10 10 ocher 5 10 10 5 10 5 5 10 5 External release agent Stearic acid 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 Absorbent sillitin 5 5 5 5 5 5 5 5 5 Adhesive Enhancer Coumarone resin 3 3 3 One One 3 2 5 3 Internal release agent PE wax 4 4 4 4 4 4 4 4 4 Plasticizer DOP 10 10 5 5 5 Anti-aging 2,2,4-trimethyl dihydroquinoline 5 5 5 5 5 5 5 5 5 Filler Carbon black 3 3 3 3 3 3 3 3 3 Crosslinking agent sulfur 3 2.5 2.5 3 2.5 2.5 3 2.5 2.5 Crosslinking accelerator M DM 2 2 2 2 2 2 2 2 2 PZ blowing agent Azodicarbonamide (Cellcom-AC system) 18 18 18 18 18 18 18 18 18 Foaming aid Urea system (Celex-A) 1.5 2 2 1.5 2 2 1.5 2 2 Heat transfer accelerator ZnO

Sample number Foot Po Composition water LOI (Limit Oxygen Index) Foaming method Firing degree Effervescent Composition ratio (wt%) 160 → 250 ℃ Foaming temperature / time required (℃ / min) Foaming rate (%) surface Cell structure R / FR Resin (N / NR / S / E / G) Flame Retardant (Al / Mg / Sb / Ocher) P / BA (DOP / AC system) 20 150 to 160/20 ′ 150-200 〃 〃 100/165 0/80/0/0/20 90/60/10/5 0/18 28.7 21 160-170 / 20 ' 〃 〃 〃 100/165 〃 80/65/10/10 〃 28.6 22 〃 200 〃 〃 100/170 〃 90/60/10/10 〃 29.3 23 150 to 160/20 ′ 150-200 〃 〃 100/165 0/0/80/0/20 90/60/10/5 10/18 28.7 24 〃 〃 〃 〃 100/165 〃 90/55/10/10 〃 28.6 25 〃 〃 〃 〃 100/160 〃 85/60/10/5 5/18 28.1 26 165-167 / 11'20 " 200 〃 〃 100/165 0/60/20/0/20 90/60/10/5 〃 28.3 27 〃 150-200 〃 〃 100/165 〃 90/55/10/10 〃 28.6 28 150 to 165/20 ′ 〃 〃 〃 100/170 〃 90/65/10/5 〃 31.1 In Table 7, R / FR is used weight ratio of resin / flame retardant, resin (N / NR / S / E / G) is NBR / NR / SBR / EPDM / GTR composition ratio, flame retardant (Al / Mg / Sb / Loess) is Al (OH) ₃ , Mg (OH) ₂ , Sb ₂ O ₃ , the use part by weight of loess, and P / BA (DOP / 5000F) is the weight ratio of the plasticizer / foaming agent.

As described above, the present invention, in the construction of a flame retardant polyolefin foam composition using a tire powder, unlike the prior art by blending the tire rubber (GTR) to a predetermined composition of polyolefin-based, rubber-based resin, but by a specific component blending conditions In addition to pursuing recycling to create an efficient and high value-added GTR, in some cases, the resin composition can be effectively constructed to avoid the use of halogen-containing compounds. It has excellent flame retardancy, mechanical properties and environmentally friendly properties, so that it can be very usefully applied to a wide range of applications such as various building materials, automobile parts, sporting goods, and other industrial products by extrusion or injection molding.

Claims (12)

In a flame retardant polyolefin foam composition containing nitrile rubber as a resin component and comprising at least one of a flame retardant, a crosslinking agent, a plasticizer, a foaming agent, a filler, a moisture absorbent, an anti-aging agent, a lubricant, and a stabilizer as a conventional additive, wherein the resin component is nitrile. 50 to 100 parts by weight of rubber, 10 to 30 parts by weight of polyvinyl chloride or chlorinated polyethylene, 0 to 100 parts by weight of ethylene-propylene copolymer and 1 to 50 parts by weight of GTR (tire powder), and the flame retardant added thereto It is composed of 10 to 100 parts by weight of Al (OH) ₃ , 30 to 90 parts by weight of Mg (OH) ₂ , 5 to 50 parts by weight of Sb ₂ O ₃ , and 5 to 20 parts by weight of ocher, and a flame retardant based on 1 part by weight of the resin component. A flame retardant polyolefin foam composition using a tire powder, characterized by containing 1 to 1.8 parts by weight and containing a conventional additive. 2. The conventional additives according to claim 1, which are 0-50 parts by weight of a plasticizer, 0-15 parts by weight of a stabilizer, 0-5 parts by weight of a crosslinking agent, 2-melcap benzothiazole (M), dibenzothiazine as a crosslinking accelerator. Di-disulfide (DM) and Zn-dimethyl-dithiocarbamate (PZ) are 0 to 3 parts by weight, 10 to 40 parts by weight of blowing agent, 0 to 3 parts by weight of foaming aid, 0 to 10 parts by weight of heat transfer accelerator, Flame retardant polyolefin using tire powder, characterized in that 0 to 5 parts by weight of external mold release agent, 0 to 4 parts by weight of internal mold release agent, 0 to 10 parts by weight of moisture absorbent, 0 to 10 parts by weight of antioxidant, and 0 to 10 parts by weight of filler. Foam composition. The flame retardant polyolefin foam composition using tire powder according to claim 1 or 2, wherein the nitrile rubber is acrylonitrile-butadiene rubber having an acrylonitrile content of 28 to 34%. The flame retardant polyolefin foam composition using tire powder according to claim 1 or 2, wherein the ethylene-propylene copolymer has an ENB content of 4.5 to 8 wt%. The flame retardant polyolefin foam composition according to claim 1 or 2, wherein the chlorinated polyethylene has a chlorine content of 36 to 42%. In a flame retardant polyolefin foam composition containing nitrile rubber as a resin component and containing a flame retardant, a crosslinking agent, a plasticizer, a foaming agent, a filler, a moisture absorbent, an anti-aging agent, a lubricant, and a stabilizer as a usual additive, the resin component is nitrile rubber and natural rubber, 50 to 100 parts by weight of one or more components of styrene rubber and ethylene-propylene copolymer, 0 to 80 parts by weight of polyethylene and 1 to 50 parts by weight of GTR, wherein the flame retardant added thereto is 10 to 100 parts by weight of Al (OH) ₃ It is contained in 30 to 90 parts by weight of Mg (OH) ₂ , 5 to 50 parts by weight of Sb ₂ O ₃ and 5 to 20 parts by weight of ocher, and contains a conventional additive, flame-retardant polyolefin using a tire powder Foam composition. According to claim 6, as a conventional additive, based on 100 parts by weight of a flame retardant, 0 to 50 parts by weight of plasticizer, 0 to 15 parts by weight of stabilizer, 0 to 5 parts by weight of crosslinking agent, 2-melcap benzothiazole (M) as a crosslinking accelerator. ), Dibenzothiadyl disulfide (DM) and Zn-dimethyl dithiocarbamate (PZ) are 0 to 3 parts by weight, 10 to 40 parts by weight of blowing agent, 0 to 3 parts by weight of foaming aid, and heat transfer accelerator. 0 to 10 parts by weight, 0 to 5 parts by weight of an external mold release agent, 0 to 4 parts by weight of an internal mold release agent, 0 to 10 parts by weight of a moisture absorbent, 0 to 10 parts by weight of an antioxidant, and 0 to 10 parts by weight of a filler. Flame retardant polyolefin foam composition using tire powder. The flame retardant polyolefin foam according to claim 6 or 7, wherein the nitrile rubber is an acrylonitrile-butadiene rubber having an acrylonitrile content of 28 to 34%, and the styrene rubber is a styrene-butadiene rubber. Composition. The flame retardant polyolefin foam composition using tire powder according to claim 6 or 7, wherein the ethylene-propylene copolymer has an ENB content of 4.5 to 8 wt%. The flame-retardant polyolefin foam composition using tire powder according to claim 7, wherein the additive further contains 6 parts by weight or less. To the resin component and flame retardant mixture of claim 1, 0 to 50 parts by weight of a plasticizer, 0 to 15 parts by weight of a stabilizer and 10 to 40 parts by weight of a blowing agent are added, followed by first mixing at 110 to 120 ° C. 0-3 parts by weight of 2-melcap benzothiazole (M), di-benzothiadyl disulfide (DM) and Zn-dimethyl dithiocarbamate (PZ) as -5 parts by weight and a crosslinking accelerator. After the addition, the method of producing a flame-retardant polyolefin foam composition using a tire powder, characterized in that the secondary mixture at 60 ~ 70 ℃ and extrusion or injection. To the resin component and flame retardant mixture of claim 6, 0 to 50 parts by weight of a plasticizer, 0 to 15 parts by weight of a stabilizer and 10 to 40 parts by weight of a blowing agent are added, followed by first mixing at 110 to 120 ° C., where the crosslinking agent 0 0-3 parts by weight of 2-melcap benzothiazole (M), di-benzothiadyl disulfide (DM) and Zn-dimethyl dithiocarbamate (PZ) as -5 parts by weight and a crosslinking accelerator. After the addition, the method of producing a flame-retardant polyolefin foam composition using a tire powder, characterized in that the secondary mixture at 60 ~ 70 ℃ and extrusion or injection.