KR100702977B1 - Polypropylene resin composition with fire retardancy having improved luster and thermal resistance - Google Patents

Abstract

The present invention relates to a flame retardant polypropylene resin composition having excellent mechanical properties such as heat resistance and impact resistance and glossiness, and exhibiting high flame retardancy, and more specifically, a high melting point halogen flame retardant and an antimony compound based on polypropylene resin as a main component. It relates to a flame retardant polypropylene resin composition comprising a talc powder and barium sulfate.

Flame Retardant Polypropylene

Description

Flame-retardant polypropylene resin composition excellent in gloss and heat resistance {POLYPROPYLENE RESIN COMPOSITION WITH FIRE RETARDANCY HAVING IMPROVED LUSTER AND THERMAL RESISTANCE}

The present invention relates to a flame retardant polypropylene resin composition having excellent mechanical properties such as heat resistance and impact resistance and glossiness, and exhibiting high flame retardancy, and more specifically, a high melting point halogen flame retardant and an antimony compound based on polypropylene resin as a main component. It relates to a flame retardant polypropylene resin composition comprising a talc powder and barium sulfate.

Polypropylene resin is widely used in the fields of injection molding, film and blow molded products in the fields of automobiles, building materials and electric parts due to its excellent processing characteristics, chemical resistance, weather resistance and high sliding properties, and is inflammable. Various organic or inorganic flame retardants are added to impart flame retardant properties. In general, a flame retardant polypropylene resin is a method of using an organic or inorganic flame retardant and antimony trioxide in combination.

The addition type flame retardant method in which a flame retardant is added to impart flame retardancy to a polypropylene resin is a method of adding at least one component selected mainly from halogen-containing organic compounds and antimony-containing inorganic compounds to the resin. Halogen-containing organic compounds, mainly bromine or chlorine compounds, have excellent flame retardancy when added to polypropylene resins, while causing serious degradation in overall physical properties such as impact strength, UV stability, heat resistance and processability of the resin itself. I have a problem. Therefore, in producing a flame retardant resin, a technique of imparting excellent flame retardancy while minimizing a decrease in physical properties of the resin is very important.

The use of flame-retardant resins was mainly interior, but as the application area is expanded to exterior products such as fan heater cases, high-impact, high-gloss and heat-resistant flame-retardant resins with excellent moldability, appearance and workability are needed. Was done. In order to increase the flowability of the resin, a flame retardant having excellent flow property should be used. In the case of polypropylene resin, a melt flame retardant having a low melting point is mainly used. However, as the molten flame retardant, tetrabromo bisphenol A-bis (2,3-dibromopropylether), bis [3,5-dibromo-4- (2 ', 3'-dibromopropyloxy) Phenyl] sulfone is superior in flame retardancy compared to flame retardants such as decabromodiphenyl ether, ethylene-bis (tetrabromo phthalimide), and bispentabromo phenoxytane, which have high melting point flame retardant, There is a problem of inferior blooming and weather resistance.

On the other hand, when used only as flame retardants such as decabromodiphenyl ether, ethylene-bis (tetrabromo phthalimide), bispentabromo phenoxytane as a high melting point flame retardant, flame retardancy that meets US UL (Underwriters Laboratories) standard Excessive addition of the flame retardant is inevitable in order to indicate that it is not preferable because serious impact resistance and glossiness decrease occurs. In addition, when excessively added, the specific gravity of the composition increases, and flamming drops (flaming drops) as an ignition source are excessively generated during combustion, and thus high flame resistance cannot be exhibited, and long-term heat stability and heat deformation resistance are inferior. .

Meanwhile, although the use of talc powder is disclosed as an inorganic filler in the examples of Korean Patent Registration No. 10-02761520000, in the resin composition containing such excess talc powder, the mechanical properties such as heat deformation temperature are excellent, but the resin composition Its surface gloss is significantly inferior, making it difficult to use for exterior parts of heat-transfer products requiring surface gloss. Other inorganic fillers include barium sulfate, calcium carbonate, mica, silica, and glass fiber. In the case of calcium, the surface glossiness of the composition is not significantly reduced, but the degree of contribution to the improvement of flame retardancy is insignificant. Therefore, in order to obtain flame retardancy of V-0, the blending content of the flame retardant and the flame retardant aid should be increased. Although the degree of contribution to flame retardancy is high, the surface glossiness of the composition is significantly inferior. Therefore, when using such inorganic filler alone, it is difficult to express flame retardancy, impact resistance, heat deformation and surface glossiness at the same time, so that V-0 grade flame retardance, impact resistance, heat deformation and excellent surface glossiness At the same time, there was an unfavorable use for the exterior parts of the required heat transfer products.

That is, even when such a high melting point flame retardant is used alone, in order to express the excellent flame retardancy of V-0 class prescribed by UL94, an inorganic filler having a high content of 10% by weight or more must be added. There is a problem that drops sharply. Due to these drawbacks, it is difficult to apply for exterior parts of high temperature heat transfer products such as fan heaters, refrigerator PCB cases, microwave air tubes, and bidet control boxes.

An object of the present invention is to improve the above-mentioned problems, without impairing the properties of polypropylene, excellent blooming resistance, expressing excellent flame resistance of V-0 grade of UL94, impact resistance, heat deformation The present invention provides an improved polypropylene resin composition having high glossiness and low specific gravity.

It is possible to provide a polypropylene resin composition in which the above problems are significantly improved by blending polypropylene with a high melting point halogen flame retardant and antimony trioxide as a flame retardant and adding talc powder and barium sulfate.

The flame retardant polypropylene resin composition of the present invention comprises 40 to 72% by weight of crystalline polypropylene resin, 18 to 25% by weight of a high melting point halogen flame retardant, 4 to 12% by weight of antimony trioxide, 1 to 8% by weight of talc powder and barium sulfate It is characterized by including 5 to 15% by weight.

In the present invention, polypropylene means a propylene olefin block copolymer or a propylene homopolymer containing 50% by weight or more of propylene polymerized units.

In the flame retardant polypropylene resin composition of the present invention, the polypropylene resin is a crystalline polypropylene homopolymer or ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl pentene, 1-heptene, 1-octene and Crystalline block copolymers of propylene with one or more compounds selected from the group consisting of 1-decene or mixtures of two or more selected from the group may be used.

The polypropylene resin may have a melt flow index of 0.5 to 40 g / 10 minutes, preferably 2 to 40 g / 10 minutes. If the melt flow index of the polypropylene resin is less than 0.5 g / 10 minutes, the moldability of the composition is inferior. If it exceeds 40 g / 10 minutes, the melt viscosity drops sharply during melting, causing a dripping phenomenon during combustion. This is because there is a problem that it is difficult to obtain V-0 flame retardancy.

 The stereoregularity of the polypropylene resin of the present invention is not particularly limited and may be any crystalline polypropylene for achieving the object of the present invention. Specifically, a crystalline polypropylene resin having an isotactic pentad fraction measured by 13 C-NMR (nuclear magnetic resonance spectrum) is 0.80 to 0.99, preferably 0.85 to 0.99, particularly preferably 0.90 to 0.99.

Examples of the flame retardant used in the present invention include known high-melting halogen compounds commonly used in polyolefins, and specific examples thereof include decabromodiphenyl ether, ethylene-bis (tetrabromo phthalimide), Bispentabromo phenoxyethane and the like.

It is preferable that the blending amount of the halogen-based flame retardant having a high melting point is 18 to 25% by weight. If the content is less than 18% by weight, it is difficult to obtain V-0 grade flame retardancy of UL94, and the composition is more than 25% by weight. This is because the impact strength of is sharply lowered, and therefore it is difficult to obtain a composition having excellent flame retardancy and mechanical strength at the same time when out of the blending amount range.

In the present invention, in order to obtain sufficient flame retardancy, a flame retardant aid such as antimony trioxide is required, and this antimony trioxide exhibits synergy when used with a flame retardant. It is preferable that it is powder form, and the average particle diameter is 0.2-4.0 micrometers. The compounding quantity of antimony trioxide is 4-12 weight%, More preferably, it is 4-10 weight%. If it is less than 4 weight%, sufficient flame retardance is difficult to be obtained, and when it exceeds 12 weight%, mechanical property becomes remarkably inferior, specific gravity becomes high, and it is not economical.

In the present invention, the use of talc powder is also intended to improve mechanical properties and heat resistance, such as composition stiffness, but it is important that talc powder has a significant effect on imparting flame retardancy. Usually, the average particle size is 2 ~ 7㎛ used, but in order to impart gloss and flame retardancy, it is preferable to use the one having an average particle diameter of 2 ~ 5㎛. The compounding quantity is 1 to 8 weight%, and when the compounding quantity is less than 1 weight%, a flame retardant effect is not enough, and when it exceeds 8 weight%, glossiness falls remarkably and it is unpreferable.

In the present invention, the use of barium sulfate has a significant effect on imparting flame retardance without reducing the glossiness of the composition. In order to maintain glossiness and impart flame retardancy, it is preferable to use one having an average particle diameter of 0.5 to 2 μm. The blending amount is 5 to 15% by weight, and when the blending amount is less than 5% by weight, the flame retardant effect is not sufficient. When the blending amount is more than 15% by weight, the effect of maintaining glossiness is significantly lowered, and the specific gravity is increased, which is undesirable. not.

In addition to the above components, the resin composition of the present invention includes additives generally used as needed, such as antioxidants, nucleating agents, thermal stabilizers, ultraviolet stabilizers, lubricants, pigments, organic fillers, antistatic agents, foaming agents, and the like. It is possible to mix and use accordingly.

The flame retardant polypropylene resin composition of the present invention can be produced by the following method. That is, a stirring-mixing apparatus for a specified amount of (A) polypropylene resin, (B) high melting point halogen-based compound (flame retardant), (C) antimony trioxide, (D) talc powder, (E) barium sulfate and various additives (E.g., a Hensel mixer (trade name), a super mixer or a tumbler mixer), stirred-mixed for 1 to 10 minutes, and melted and kneaded using a rolling mill or an extruder at a temperature of 180 ° C to 230 ° C to form a resin composition pellet. Can be obtained.

By molding the pellets thus obtained by any molding method such as injection molding or extrusion molding, a polypropylene resin molded article can be obtained.

The polypropylene resin molded article thus obtained is composed of a high melting point halogen-based compound as a flame retardant, antimony trioxide, talc powder, and barium sulfate as a flame retardant, and thus has excellent long-term heat resistance, heat deformation resistance, impact resistance, and glossiness. Excellent flame retardancy of grade can be obtained. A molded article composed of such a highly functional resin composition is very suitable for use in exterior parts of high-temperature heat transfer products, automobiles, and building materials.

      The present invention can be understood in more detail by the following examples and comparative examples, the following examples are only for illustrating the present invention and are not intended to limit the protection scope of the present invention.

Examples and Comparative Examples

How to measure

1) Izod impact strength

The injection molded molded article had a thickness of 3.2 mm and was based on the ASTM D256 test standard.

2) heat deflection temperature

      A test specimen having a length of 127.0 mm, a width of 12.7 mm, and a thickness of 6.4 mm was molded using an injection molding machine, and subjected to a load of 4.6 kgf / cm 2 of the ASTM D648 test standard.

3) flammability

      The vertical combustion test of UL subject 94 (Underwrites Laboratories Incorporation) "Combustibility Test of Plastic Material for Mechanical Components" was based on the vertical phase. The thickness of the specimen used was 1/16 inch.

4) Glossiness

      In order to measure the glossiness of the surface of the molded article, a flat sheet of 100 × 100 × 2 mm was prepared, and the glossiness represented by a 60 ° reflection angle was measured using a gloss meter.

Example 1

      5.5 kg of crystalline ethylene-propylene block copolymer having a melt index (melt flow amount of melted resin for 10 minutes at 230 ° C. under a load of 2.16 kg) of 8 g / 10 min as a polypropylene resin, and bispentaviro as a high melting point halogen flame retardant. Mother phenoxy ethane [brand name: S-8010, Albermale USA] 2.3 kg, antimony trioxide [brand name: SW, Ilsung antimony company] 700 g, talc powder [brand name: KCM6300, KOCH company] 300 g, barium sulfate [brand name: HD- 80, solvay company] 10 g of calcium stearate and 30 g of antioxidant as an additive were charged to a Hensel mixer (trade name) and stirred-mixed for 3 minutes. The resulting mixture was melt-extruded at 180-230 ° C. using an extruder with a diameter of 30 mm to prepare pellets.

[Examples 2 to 3 and Comparative Examples 1 to 2]

      The same ingredients as in Example 1 were charged to a Hensel mixer (trade name) except that the compounding ratio of the polypropylene resin and the high melting point halogen flame retardant in Example 1 was replaced by the content ratio shown in Table 1, followed by stirring. After mixing, the resulting mixture was melt-extruded under the same conditions as in Example 1 to prepare pellets.

      The pellets obtained in Examples 1 to 3 and Comparative Examples 1 to 2 were dried at 100 ° C. for 3 hours, and molded using an injection molding machine having a maximum temperature of 230 ° C. to test flame resistance and mechanical properties. After preparing a predetermined test piece for, the results of measuring the flame retardancy, mechanical properties are shown in Table 1.

      As can be seen in Table 1, Examples 1 to 3 manufactured according to the contents of the present invention, while maintaining the excellent flame retardancy of V-0 class, at the same time excellent characteristics of impact strength, heat deformation temperature and glossiness It is shown.

However, in the case of Comparative Examples 1 to 2, when the blending amount of the high melting point halogen flame retardant is less than 18 wt%, excellent flame retardancy of V-0 grade cannot be obtained, and when the blending amount exceeds 25 wt%, impact strength and glossiness are performed. It was confirmed that the fall significantly compared to the example.

Example 4

5.8 kg of crystalline ethylene-propylene block copolymer having a melt index (melt flow rate of the melt for 10 minutes at 230 ° C. under a load of 2.16 kg) of polypropylene resin, 8 g / 10 minutes, bispentabbro as a high melting point halogen flame retardant Mother phenoxy ethane [brand name: S-8010, Albermale USA] 2.3 kg, antimony trioxide [brand name: SW, Ilsung antimony company] 400 g, talc powder [brand name: KCM6300, KOCH company] 300 g, barium sulfate [brand name: HD- 80, solvay company] 10 g of calcium stearate and 30 g of antioxidant as an additive were charged to a Hensel mixer (trade name) and stirred-mixed for 3 minutes. The resulting mixture was melt-extruded at 180-230 ° C. using an extruder with a diameter of 30 mm to prepare pellets.

[Example 5 and Comparative Examples 3 to 4]

The same ingredients as in Example 4 were charged to a Hensel mixer (trade name) except that the compounding ratio of the polypropylene resin and the antimony trioxide as the flame retardant was replaced with the content ratio shown in Table 1, followed by stirring-mixing to produce The pelleted mixture was melt-extruded under the same conditions as in Example 4.

The pellets obtained in Examples 4 to 5 and Comparative Examples 3 to 4 were dried at 100 ° C. for 3 hours, and molded using an injection molding machine in which the maximum temperature of the cylinder was fixed at 230 ° C., to test flame resistance and mechanical properties. Table 1 shows the results of measuring the flame retardancy and mechanical properties after preparing the test specimens.

As can be seen in Table 1, in the case of Examples 4 to 5 manufactured in accordance with the contents of the present invention, not only the excellent flame retardancy of the V-0 grade was obtained, but also the overall mechanical resistance such as impact resistance, heat deformation temperature and glossiness. It was possible to obtain a resin composition having high physical properties and appearance gloss.

However, in Comparative Examples 3 to 4, when the amount of antimony trioxide as a flame retardant aid was less than 4% by weight, excellent flame retardancy of the V-0 grade could not be obtained, and when the amount exceeded 12% by weight, impact strength and glossiness were performed. It was confirmed that the fall significantly compared to the example.

Example 6

5.5 kg crystalline propylene homopolymer with 10 g / 10 min melt index (melt flow rate for 10 min at 230 ° C under a load of 2.16 kg) as polypropylene resin, bispentabromo phenoxy as high melting point halogen flame retardant Ethane [brand name: S-8010, USA Albermale company] 2.3 kg, antimony trioxide [brand name: SW, Ilsung antimony company] 700 g, talc powder [brand name: KCM6300, KOCH company] 500 g, barium sulfate [brand name: HD-80, solvay G) 1.0 kg and 10 g of calcium stearate and 30 g of antioxidant as an additive were charged to a Hensel mixer (trade name) and stirred-mixed for 3 minutes. The resulting mixture was melt-extruded at 180-230 ° C. using an extruder with a diameter of 30 mm to prepare pellets.

[Examples 7 to 11 and Comparative Examples 5 to 15]

The same ingredients as in Example 6 were charged to a Hensel mixer (trade name) except that the compounding ratio of polypropylene resin, high melting point halogen flame retardant, antimony trioxide, talc powder and barium sulfate was replaced by the content ratios shown in Table 1. After stirring and mixing, the resulting mixture was melt-extruded under the same conditions as in Example 6 to prepare pellets.

The pellets obtained in Examples 6 to 11 and Comparative Examples 5 to 15 were dried at 100 ° C. for 3 hours, and molded using an injection molding machine having a maximum temperature of 230 ° C. to test flame resistance and mechanical properties. After preparing a predetermined test piece for the, the results of measuring the flame retardancy and mechanical properties are shown in Table 1.

As shown in Table 1, in Examples 6 to 11 prepared according to the present invention, when blended with talc powder and barium sulfate at the same time, V-0 grade flame retardancy, impact resistance, heat deformation resistance, gloss, etc. At the same time, it was excellent, and it was confirmed that it was suitable for use for exterior parts of heat-transfer products requiring excellent flame retardancy, excellent mechanical properties and surface glossiness of V-0 grade.

However, in Comparative Examples 5 to 15, when talc powder, barium sulfate, and other inorganic fillers were used alone, the composition was excellent in flame retardancy, impact resistance, heat deformation, and surface gloss. It was difficult to do it. That is, when talc powder alone is used, the impact resistance and surface gloss are excellent, but flame retardancy and heat deformation are inferior, and when barium sulfate is used alone, the surface gloss is excellent, but the glow time is excessive in the flame retardancy test. Therefore, it was difficult to show the V-0 grade flame retardancy, and when calcium carbonate was used as another inorganic filler, not only the surface gloss was inferior, but also the combustion time and the residual flame time were excessive. It was difficult to obtain. In addition, when silica or glass fiber is used, mechanical properties such as heat deformation resistance and impact resistance are excellent, but surface glossiness is significantly inferior, and when used alone, the flame retardancy, impact resistance, heat deformation resistance and surface glossiness are simultaneously expressed. It was difficult to be used for exterior parts of heat-transfer products requiring V-0 grade flame retardancy, excellent mechanical properties and excellent surface gloss.

Example 12

      5.5 kg of crystalline ethylene-propylene block copolymer having a melt index (melt flow amount of melted resin for 10 minutes at 230 ° C. under a load of 2.16 kg) of 8 g / 10 min as a polypropylene resin, and bispentaviro as a high melting point halogen flame retardant. Mother phenoxy ethane [brand name: S-8010, Albermale, USA] 2.3 kg, antimony trioxide [brand name: SW, Ilsung antimony company] 700 g, talc powder [brand name: KCM6300, KOCH company] 400 g, barium sulfate [brand name: HD- 80, solvay] 10 g of calcium stearate and 30 g of antioxidant as an additive were charged to a Hensel mixer (trade name) and stirred-mixed for 3 minutes. The resulting mixture was melt-extruded at 180-230 ° C. using an extruder with a diameter of 30 mm to prepare pellets.

[Examples 13 to 15]

The same ingredients as in Example 12 were charged in a Hensel mixer (trade name) except that the polypropylene resin and the high melting point halogen flame retardant were replaced by the content ratios shown in Table 1, followed by stirring-mixing. The resulting mixture was melt-extruded under the same conditions as in Example 12 to prepare pellets.

The pellets obtained in Examples 12 to 15 were dried at 100 ° C. for 3 hours, and molded using an injection molding machine having a maximum temperature of 230 ° C. to prepare a constant test piece for testing flame resistance and mechanical properties. After that, the results of measuring flame retardancy and mechanical properties are shown in Table 1.

As shown in Table 1, flame retardancy and impact resistance even when the type of polypropylene resin and the type of high melting point halogen flame retardant were replaced with those shown in Table 1 in the state in which talc powder and barium sulfate were mixed in the amounts shown in Table 1 It was confirmed that excellent compositions such as heat deformation and surface glossiness can be obtained at the same time.

As can be seen in the above examples and comparative examples, the polypropylene resin composition prepared by the present invention exhibits excellent impact resistance, heat deformation temperature and gloss while simultaneously exhibiting excellent flame resistance of UL94 V-0 grade. It is very suitable for use in manufacturing exterior parts, electrical appliances and automobile parts, building materials, interior decoration materials, etc. of heat-transfer products requiring performance.

Claims (4)

(A) 40 to 72% by weight of polypropylene resin, (B) 18 to 25% by weight of high melting point halogen flame retardant, (C) 4 to 12% by weight of antimony trioxide, (D) 1 to 8% by weight of talc powder, and (E Flame retardant polypropylene resin composition comprising 5 to 15% by weight of barium sulfate, and has a flame retardancy of UL94 V-0 grade. The flame retardant polypropylene resin composition according to claim 1, wherein the polypropylene resin is a crystalline polypropylene homopolymer or a crystalline ethylene-propylene block copolymer. The flame-retardant polypropylene resin composition according to claim 1 or 2, wherein the melt flow index of the polypropylene resin is 0.5 g / 10 minutes to 40 g / 10 minutes.       The flame retardant polypropylene resin composition according to claim 1, wherein the high melting point halogen flame retardant is decabromodiphenyl ether, ethylene-bis (tetrabromo phthalimide), or bispentabromo phenoxytane.