JP2010241893A - Flame-retardant polypropylene resin composition and molding comprising the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermoplastic resin material having high flame retardancy (self-extinguishing property), which is free from generating a toxic gas during burning or bleed-out of a flame retardant, which maintains excellent mechanical resin performances even when a large amount of an inorganic flame retardant is compounded to increase the flame retardancy of the thermoplastic resin, and which exhibits improved whitening resistance and wear resistance against external force, and favorable flexibility and moldability, and to provide a flame-retardant molding using the material. <P>SOLUTION: This flame-retardant polypropylene resin composition is obtained by compounding 50 to 300 parts by weight of a metal hydrate component (B), 1 to 20 parts by weight of a modified polyolefin resin component (C), and 0 to 100 parts by weight of a thermoplastic elastomer component (D), into 100 parts by weight of a propylene-ethylene copolymer component (A) having specified characteristics (i) and (ii) (not shown in figures). The flame-retardant molding is obtained by using the above composition. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a flame retardant polypropylene-based resin composition and a molded article comprising the same, and more specifically, a large amount of an inorganic flame retardant that does not cause the generation of toxic gas during combustion and does not bleed out the flame retardant. Even if the flame retardancy of the thermoplastic resin is sufficiently increased by blending, it possesses excellent mechanical resin performance (especially tensile elongation) and has resistance to whitening against external forces (whitening phenomenon of bent parts of products due to external force) ) And abrasion resistance, and has good flexibility, moldability, etc., and has a highly flame-retardant (self-extinguishing) polypropylene resin composition, and extrusion using the same The present invention relates to a molded product such as a molded body.

Since plastic materials that are heavily used as major industrial materials are generally flammable, there has been a strong demand for flame retardancy for the safety of using molded products made from plastic materials.
Among the plastic materials, flame retardants for highly versatile thermoplastic resins (and their elastomers) are mainly divided into flame retardants for the resins themselves or the combination of flame retardants in the resins. Among these methods, a method using a flame retardant that is comparatively simple and sufficiently flame retardant is widely used.

As a flame retardant method by blending the flame retardant, conventionally, as a basic method, blending of antimony oxide and halide into a thermoplastic resin has been performed, but such a flame retardant composition is In the event of a fire, there is a problem that a hazardous halogen gas is generated and a danger is generated.
Formulation of organic flame retardants such as phosphorous and bromine is also known, but with such organic flame retardants, the flame retardant bleeds out on the surface of the thermoplastic resin molded product and flame retardant in the long term It contains problems that cannot be maintained.
In order to avoid such problems, inorganic flame retardants, particularly aluminum hydroxide, which generate no harmful gas during combustion, have no problem with toxicity as additives, and have no bleed out of flame retardants. Flame retardant materials using a hydrated metal compound such as magnesium hydroxide or a blend of these with magnesium carbonate are regarded as important.

However, in such a flame retardant material, in order to impart sufficient flame retardancy, it is necessary to blend a large amount of hydrated metal compound, resulting in flexibility, abrasion resistance, whitening resistance, There is a disadvantage that various performances such as mechanical strength (particularly, tensile elongation at break) are remarkably lowered.
As a technique for improving such a problem, by adding aluminum hydroxide and / or magnesium, an ethylene-unsaturated carboxylic acid copolymer and an epoxy group-containing compound to a thermoplastic resin, flame retardancy is achieved, and external force is used. Although a flame retardant composition has been disclosed in which whitening resistance, trauma resistance and cold resistance are improved (Patent Document 1), even if various properties are improved, the flame retardancy has not yet been satisfied. .
A flame retardant resin composition excellent in moldability was proposed by blending an unsaturated carboxylic acid or its derivative-modified polyethylene, a metal hydrate, and an ethylene-based copolymer with a polypropylene resin (Patent Document). 2) The problem of lack of wear resistance and whitening resistance was inherent.
In addition, a flame-retardant and wear-resistant resin composition in which a propylene-ethylene block copolymer, a polyolefin-based elastomer, and a metal hydroxide are blended to improve the dispersibility of the flame retardant has also been presented ( Patent Document 3), the whitening resistance is still insufficient, and even if the wear resistance is improved, it is not fully satisfactory.

Furthermore, as a method of using a specific resin excellent in heat resistance and flexibility, the elution component in the elution curve representing the relationship between the elution temperature and the integrated weight ratio of the elution component by the temperature rising elution fractionation method is specified, Although a flame retardant soft resin composition comprising 100 parts by weight of a propylene-ethylene block copolymer and 80 to 400 parts by weight of a metal hydroxide having a maximum peak temperature indicated by differential scanning calorimetry is also disclosed ( In Patent Document 4), this resin composition is whitened when an external force is applied, and a defect that the appearance is not satisfactory when a molded product is put into practical use is manifested.
Recently, polypropylene resins manufactured with metallocene catalysts and specified in the elution curve of MFR and temperature rising elution fractionation method have been presented, and a large amount of inorganic flame retardant is added to give sufficient flame retardancy. However, both flame retardancy and mechanical properties (especially tensile elongation) are satisfied (Patent Document 5), but there is still a problem that whitening occurs due to external force in the molded product, and wear resistance. I have not been satisfied with sex.

  As described above, in view of the transition of the background art and the current state of flame retardancy of thermoplastic resins, there is no risk of generation of toxic gas during combustion, and there is no bleed out of the flame retardant. Even if the flame retardancy of the thermoplastic resin is sufficiently increased by blending, it possesses excellent mechanical resin performance (especially tensile elongation) and has resistance to whitening against external forces (whitening phenomenon of bent parts of products due to external force) Etc.) and wear resistance have been improved, and a highly flame-retardant (self-extinguishing) thermoplastic resin material that has both good flexibility and moldability has not yet been realized and its development is desired. Has been.

JP 63-189462 A (claim 1) JP 7-252388 A (summary) JP 2000-26696 A (summary) Japanese Patent Laid-Open No. 11-60888 (summary) JP 2004-26968 A (summary)

  In view of the above-mentioned problems of the prior art, the object of the present invention is to add a large amount of an inorganic flame retardant, which does not cause the generation of toxic gas during combustion and does not bleed out the flame retardant, and makes it difficult for thermoplastic resins. Flame retardant (self-extinguishing) that possesses excellent mechanical resin performance even when the flammability is sufficiently increased, has improved whitening resistance and abrasion resistance against external forces, and has good flexibility and moldability. It is an object of the present invention to provide a thermoplastic resin material having high property) and a flame-retardant molded article using the same.

  As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention have added a metal hydrate component (B) and a modified polyolefin resin to a propylene-ethylene copolymer component (A) having specific characteristics. Component (C), or thermoplastic elastomer component (D) in addition to these components, are blended in specific proportions, resulting in excellent mechanical properties, whitening resistance, abrasion resistance, etc. and flame resistance (self-extinguishing) It has been found that a thermoplastic resin material having a high property) can be obtained, and the present invention has been completed.

That is, according to the first aspect of the present invention, the metal hydrate component (B) 50 is added to 100 parts by weight of the propylene-ethylene copolymer component (A) having the following characteristics (i) to (ii). A flame-retardant polypropylene-based resin composition comprising: ~ 300 parts by weight, 1 to 20 parts by weight of a modified polyolefin resin component (C), and 0 to 100 parts by weight of a thermoplastic elastomer component (D) Provided.
(I) In the temperature-loss tangent (tan δ) curve obtained by solid viscoelasticity measurement (DMA), the peak due to the glass transition observed in the temperature range of −60 to 20 ° C. is a single peak. The temperature is 0 ° C. or lower.
(Ii) In a TREF elution curve obtained as a plot of elution amount (dwt% / dT) against temperature by a temperature rising elution fractionation method (TREF) in a temperature range of −15 ° C. to 140 ° C. using an o-dichlorobenzene solvent. And the following characteristics (ii-A) to (ii-C).
(Ii-A) Two peaks are observed in the elution curve, the peak T (A1) observed on the high temperature side is in the range of 65 to 95 ° C., and the peak T (A2) observed on the low temperature side is 45 ° C. It is below.
(Ii-B) The amount W (A2) of the component (A2) eluted up to the temperature T (A3) at the midpoint between the T (A1) and T (A2) peaks is 5 to 70 wt%, It is a propylene / ethylene random copolymer containing 6 to 15 wt% of ethylene.
(Ii-C) The amount W (A1) of the component (A1) to be eluted after elution of the component to be eluted by T (A3) is 95 to 30 wt%, and the propylene single weight containing 0 to 6 wt% of ethylene It is a polymer or a propylene / ethylene random copolymer.

According to the second invention of the present invention, in the first invention, the propylene-ethylene copolymer component (A) further has the following characteristics (iii): flame retardancy A polypropylene resin composition is provided.
(Iii) 95-30 wt% of a crystalline propylene homopolymer component or a crystalline propylene-ethylene random copolymer component (A1) having an ethylene content of 0-6 wt% in the first step using a metallocene catalyst; It is obtained by sequentially polymerizing 5-70 wt% of a low crystalline propylene-ethylene random copolymer component (A2) having an ethylene content of 6-15 wt% in two steps.

According to the third invention of the present invention, in the first or second invention, the propylene-ethylene copolymer component (A) further has the following characteristic (iv): A flammable polypropylene resin composition is provided.
(Iv) In a TREF elution curve obtained as a plot of elution amount (dwt% / dT) against temperature by a temperature rising elution fractionation method (TREF) in a temperature range of −15 ° C. to 140 ° C. using an o-dichlorobenzene solvent. And the following characteristics (iv-A) to (iv-D).
(Iv-A) Two peaks are observed in the elution curve, the peak T (A1) observed on the high temperature side is in the range of 65 to 88 ° C, and the peak T (A2) observed on the low temperature side is 45 ° C. It is below.
(Iv-B) The amount W (A2) of the component (A2) eluted up to the temperature T (A3) at the midpoint between the T (A1) and T (A2) peaks is 30 to 70 wt%, It is a propylene / ethylene random copolymer containing 8 to 14 wt% of ethylene.
(Iv-C) Propylene / ethylene having an amount W (A1) of the component (A1) to be eluted after elution of the component to be eluted by T (A3) is 70 to 30 wt%, and the component contains 1 to 5 wt% of ethylene. It is a random copolymer.
(Iv-D) The temperature T (A4) at which 99 wt% is eluted is 90 ° C. or less, and the temperature difference ΔT (T (A4) −T (A1)) from the peak T (A1) to T (A4) is 5. It is below ℃.

  According to the fourth invention of the present invention, in any one of the first to third inventions, the metal hydrate component (B) is at least one selected from aluminum hydroxide, magnesium hydroxide or hydrotalcite. A flame-retardant polypropylene resin composition is provided.

  According to a fifth aspect of the present invention, there is provided a flame retardant polypropylene-based resin composition characterized in that in any one of the first to fourth aspects, the present invention is for a self-extinguishing molded article.

  Furthermore, according to the sixth aspect of the present invention, there is provided a molded body obtained by molding the flame-retardant polypropylene resin composition according to any one of the first to fifth aspects.

  Moreover, according to the seventh invention of the present invention, there is provided an extruded product characterized in that the molded product according to the sixth invention is produced by extrusion molding.

  According to the present invention, a large amount of an inorganic flame retardant that does not cause the generation of toxic gas during combustion (at the time of a fire) and that does not bleed out the flame retardant, sufficiently increases the flame retardancy of the thermoplastic resin. However, it has excellent mechanical resin performance (particularly tensile strength), improved whitening resistance against external forces (resistance to whitening phenomenon of bent parts of products due to external force) and wear resistance, and good It is possible to provide a thermoplastic resin material for molded articles having high flame retardancy (self-extinguishing property) and a flame retardant molded article thereby having both flexibility and moldability.

  In the present invention, as described above, the propylene-ethylene copolymer component (A) having the following characteristics (i) to (ii) (hereinafter sometimes abbreviated as “component (A)”) 100. The metal hydrate component (B) (hereinafter also abbreviated as “component (B)”) 50 to 300 parts by weight and the modified polyolefin resin component (C) (hereinafter “component (C 1) to 20 parts by weight and a thermoplastic elastomer component (D) (hereinafter also abbreviated as “component (D)”) to 100 parts by weight. A flame-retardant polypropylene-based resin composition characterized by the above, and a molded product obtained by molding the resin composition, or an extrusion-molded product. Hereinafter, basic characteristics, constituent components, molded articles, molding methods thereof, and the like of the flame-retardant polypropylene resin composition of the present invention will be described in detail.

1. About flame retardancy Generally, plastic materials, especially thermoplastic resin molded products are generally flammable, and therefore there has been a strong demand for flame retardancy for safety in the use of molded products.
Conventionally, in polypropylene resins, a large amount of inorganic flame retardants must be blended to provide sufficient flame retardancy, and satisfy mechanical properties, particularly tensile elongation properties and flame retardant properties. It was difficult to do.

In the present invention, the case where the oxygen index in JIS K7201 is less than 21 is referred to as flammability, the case where the oxygen index is near 21 or more is referred to as flame retardancy, and when flame retardancy is high, self-extinguishing is more preferable. It is called sex (self-extinguishing). The oxygen index (OI) is:
A sheet of 3 mm was prepared by compression (press) molding at a temperature of 180 ° C., and a test piece having a width of 6.5 mm and a length of 150 mm was cut. The obtained test piece was measured for oxygen index according to the method of JIS K-7201.
Using an oxygen measuring device, the oxygen index was determined by measuring the minimum oxygen flow rate required for the test piece to burn continuously for 3 minutes or longer, or to keep the burned length after the flame reaching 50 mm or longer. .
OI (%) = {[O ₂ ] / ([O ₂ ] + [N ₂ ])} × 100
[O ₂ ]: Flow rate of oxygen L / min [N ₂ ]: Flow rate of nitrogen L / min

2. About the composition of the resin composition of the present invention (1) Basic structure It is a polypropylene resin material that is employed in the present invention and has excellent flexibility and transparency, heat resistance and rigidity, and is excellent in moldability. The specific propylene-ethylene random block copolymer has excellent compatibility of each resin component, and if used as a flame retardant resin material, the dispersibility of a large amount of inorganic flame retardant is greatly improved. At the same time, since the stress when strain is applied is reduced, it is possible to prevent the stress from being applied to the interface between the polypropylene resin and the flame retardant, thereby preventing the mechanical strength (particularly, tensile elongation) from being lowered, and further improving the resistance. Whitening property is also improved.
The flame-retardant polypropylene resin composition of the present invention comprises a specific propylene-ethylene copolymer component (A), a metal hydrate component (B), a modified polyolefin resin component (C), and as necessary. It consists of a thermoplastic elastomer component (D), and an additional component can be added within a range that does not impair the efficacy (action effect) of the present invention. Each component must meet various requirements to solve problems. The detailed description of each component is added below.

(2) Propylene-ethylene copolymer component (A)
(I) Basic features In conventional polypropylene resins, in order to improve the tensile elongation at break of a relatively high crystallinity component mainly composed of propylene, an ethylene elastomer is blended as a low crystallinity component. The methods of producing low-crystalline components containing ethylene by sequential polymerization and using a so-called block copolymer are widely known to those skilled in the art, but these low-crystalline components are components mainly composed of propylene. Because of their low compatibility with each other, they are phase-separated and each has a phase-separated structure that becomes a separate phase.
When a large amount of an inorganic filler (inorganic flame retardant) for imparting flame retardancy is added to the resin having such a structure, the softening temperature and compatibility with the filler are different in each phase. Since the filler is unevenly distributed and breakage is likely to occur at a portion where the inorganic filler concentration is high, the effect of improving the tensile elongation at break cannot be sufficiently exhibited. Further, when an external force is applied, peeling occurs not only between the inorganic filler and the resin but also at the interface of each phase of the resin component, resulting in a problem that bending whitening is extremely deteriorated.
The propylene-ethylene copolymer component (A) in the present invention is different from the above-mentioned conventional propylene-based resin material. As a basic feature, the propylene-ethylene-based copolymer component (A) It is roughly divided into two components (A1) and (A2) as defined by the following characteristics.

(Ii) Identification by solid viscoelasticity measurement The propylene-ethylene copolymer component (A) used in the present invention includes a low crystalline component (A2) for improving the tensile elongation (tensile elongation at break). However, it is necessary not to have a phase separation structure with the relatively high crystallinity component (A1) mainly composed of propylene.

The fact that the phase separation structure is not taken is that in the temperature-loss tangent (tan δ) curve obtained by solid viscoelasticity measurement (DMA), the tan δ curve has a single peak between −60 and 20 ° C. It is specified that the peak temperature is 0 ° C. or lower.
This is because, in solid viscoelasticity measurement, the glass transition temperature of propylene-ethylene copolymer resin is usually observed between -60 and 20 ° C. as the peak of the tan δ curve. While only the glass transition temperature is observed, the phase separation structure is based on showing a plurality of peaks because the glass transition temperature of each phase is observed separately.

Here, the solid viscoelasticity measurement is specifically performed by applying a sinusoidal strain of a specific frequency to a strip-shaped sample piece and detecting the generated stress. Here, the frequency is 1 Hz, and the measurement temperature is raised stepwise from −60 ° C. until the sample is melted and cannot be measured. Further, it is recommended that the magnitude of distortion is about 0.1 to 0.5%. From the obtained stress, the storage elastic modulus and the loss elastic modulus are obtained by a known method, and the loss tangent (= loss elastic modulus / storage elastic modulus) defined by the ratio thereof is plotted against the temperature. A sharp peak is shown in the temperature region. In general, the peak of tan δ at 0 ° C. or lower is for observing the glass transition of the amorphous part, and here, this peak temperature is defined as the glass transition temperature Tg (° C.). The peak temperature due to glass transition is preferably −5 ° C. or lower, more preferably −20 to −10 ° C.
In the entire measurement temperature range, another relaxation peak may appear at about 20 to 120 ° C., which is crystal relaxation called α relaxation, which is distinguished from the glass transition that is the subject of the present invention.

(Iii) Temperature rising elution fractionation method (TREF)
The low crystalline propylene / ethylene random copolymer component (A2) contained in the propylene-ethylene copolymer component (A) used in the present invention does not have a phase-separated structure and has sufficient tensile elongation at break. Therefore, it is necessary to increase the ethylene content to sufficiently reduce the crystallinity, and the compatibility decreases as the ethylene content increases. Must-have.
Further, the propylene / ethylene random copolymer component (A1), which is contained in the propylene-ethylene copolymer component (A) used in the present invention, has a relatively low crystallinity distribution on the high crystal side. Since the crystallinity distribution is narrow, the tensile fracture elongation is improved by taking a more uniform and fine crystal structure.

The crystallinity, crystallinity distribution, and ratio of these components are specified by a temperature rising elution fractionation method (TREF).
The technique for evaluating the crystallinity distribution of a propylene-ethylene copolymer by TREF is well known to those skilled in the art. For example, detailed measurement methods are shown in the following documents. G. Glockner, J. et al. Appl. Polym. Sci. : Appl. Polym. Symp. 45, 1-24 (1990)
L. Wild, Adv. Polym. Sci. 98, 1-47 (1990)
J. et al. B. P. Soares, A .; E. Hamielec, Polymer; 36, 8, 1639-1654 (1995)
In TREF measurement, the lower the crystallinity, the lower the elution, and the higher the crystallinity, the higher the elution, so it is possible to accurately grasp the distribution of the crystallinity of the polypropylene resin. .
The propylene-ethylene random block copolymer in the present invention has a large difference in crystallinity of each of the components (A1) and (A2), and both components can be accurately separated by TREF.

  In the present invention, the TREF measurement is specifically measured as follows. A sample is dissolved in o-dichlorobenzene (containing 0.5 mg / mL BHT) at 140 ° C. to prepare a solution. After this is introduced into a TREF column at 140 ° C., it is cooled to 100 ° C. at a temperature decreasing rate of 8 ° C./min, subsequently cooled to −15 ° C. at a temperature decreasing rate of 4 ° C./min, and held for 60 minutes. Thereafter, o-dichlorobenzene as a solvent (containing 0.5 mg / mL BHT) is allowed to flow through the column at a flow rate of 1 mL / min, and components dissolved in o-dichlorobenzene at −15 ° C. in the TREF column. Elution is performed for 10 minutes, and then the column is linearly heated to 140 ° C. at a temperature increase rate of 100 ° C./hour to obtain an elution curve along the temperature increase.

(Iv) Identification by peak temperature in the elution curve The elution curve shows the elution amount (dwt% /%) with respect to the temperature by the temperature rising elution fractionation method (TREF) in the temperature range of -15 ° C to 140 ° C using an o-dichlorobenzene solvent. It is a TREF elution curve obtained as a plot of dT).
Since the propylene-ethylene copolymer component (A) used in the present invention is roughly composed of two components and has different crystallinity, two peaks are observed in the TREF elution curve. The fact that two peaks are not observed means that there is only one component, the amount of one is so small that it is not observed, or the crystallinity distribution is so wide that no peak is shown. Therefore, it is necessary to observe two peaks in the propylene-ethylene copolymer component (A) used in the present invention.

In TREF measurement, the higher the elution temperature, the higher the crystallinity, and the lower the component, the lower the crystallinity. If the propylene-ethylene random copolymer component (A1) contained in the propylene-ethylene copolymer component (A) used in the present invention has relatively high crystallinity, the crystallinity is too low. Crystallinity should not be reduced excessively to cause a problem such as a significant decrease in heat resistance, and the peak temperature T (A1) needs to be 65 ° C. or higher. On the other hand, if the crystallinity becomes too high, the tensile breaking elongation decreases, so T (A1) needs to be 95 ° C. or lower.
On the other hand, the low crystalline propylene / ethylene random copolymer component (A2) contained in the propylene-ethylene copolymer component (A) used in the present invention is tensile when the crystallinity is not sufficiently lowered. Since the effect of improving the breaking elongation cannot be exhibited, the peak temperature T (A2) needs to be 45 ° C. or lower.

The propylene / ethylene random copolymer component (A1) having a relatively high crystallinity and the low crystallinity propylene / ethylene random copolymer component (A2) contained in the propylene-ethylene copolymer component (A) are: Separation can be achieved at a temperature T (A3) between the peaks of both components observed in the TREF elution curve.
Here, when expressed accurately by a mathematical expression, T (A3) = {T (A1) + T (A2)} / 2.
At this time, the component eluted by T (A3) is a low crystalline propylene / ethylene random copolymer component (A2), and the amount W (A2) is 5 to 70 wt%. In accordance with this, the component after elution by T (A3) (after elution) is a propylene / ethylene random copolymer component (A1) having relatively high crystallinity, and its amount W (A1) is 95 to 30 wt%.

W (A2) is a component necessary for improving the tensile elongation at break, and when W (A2) is less than 5 wt%, a sufficient improvement effect cannot be obtained, so W (A2) is at least 5 wt%. In order to exhibit a sufficient improvement effect, it is preferably 30 wt% or more, more preferably 40 wt% or more. That is, W (A1) is 95 wt% or less, preferably 70 wt% or less, and more preferably 60 wt% or less. On the other hand, if there is too much W (A2), that is, if the amount of the component having relatively high crystallinity is too small, problems such as deterioration of moldability and deterioration of heat resistance occur, so W (A2) is 70 wt% or less. And is preferably 60 wt% or less. That is, W (A1) needs to be 30 wt% or more, and preferably 40 wt% or more.
The components separated at this time are respectively taken out and analyzed in each component, whereby the ethylene content in each component can be measured. Here, the low crystalline propylene / ethylene random copolymer component (A2) eluting up to T (A3) cannot exhibit the effect of improving the tensile breaking elongation unless the crystallinity is sufficiently lowered. Therefore, the peak temperature T (A2) needs to be 45 ° C. or less, preferably 10 to 40 ° C., more preferably 20 to 30 ° C. At this time, since the crystallinity of the propylene / ethylene random copolymer tends to decrease as the ethylene content increases, it is necessary to contain 6 wt% or more, preferably 8 wt% or more of ethylene in the present invention. On the other hand, since the phase separation structure is taken when the ethylene content becomes too large, it is essential to keep it within a range in which phase separation does not occur, and it is necessary to be at most 15 wt%, preferably 14 wt%.

On the other hand, the propylene / ethylene random copolymer component (A1) having a relatively high crystallinity after removing the components eluted by T (A3) (after elution) is to maintain moldability and heat resistance. The peak T (A1) needs to be in the range of 65 to 95 ° C, preferably 69 to 88 ° C, more preferably 73 to 83 ° C. If the crystallinity of the component (A1) is too high, the compatibility of the resin component is lowered. At this time, the ethylene content is in the range of 0 to 6 wt%, preferably 1 to 5 wt%, more preferably 2 to 4 wt%. It will be necessary.
Here, if the crystallinity of the component (A1) is high, even if the compatibility is improved by the component (A2), it is preferable to add as much inorganic filler as possible to improve the flame retardancy. Sometimes the tensile elongation at break is insufficient. In order to further improve this, it is preferable that the crystallinity of the component (A1) is also in a specific range.
That is, the crystallinity of the component (A1) itself is lowered within a range in which heat resistance and moldability can be maintained, and by selecting one having a narrow crystallinity distribution, the crystal structure is refined and the tensile elongation at break is improved. For this purpose, the ethylene content in the component (A1) is preferably 1 wt% or more, and the peak temperature T (A1) in the TREF elution curve, which is a measure of crystallinity, is preferably 88 ° C. or less. At this time, even if T (A1) decreases, the crystallinity distribution is widened, and if there are many highly crystalline components, the improvement effect is reduced. Therefore, the temperature T (A4) at which 99 wt% is eluted is 90 ° C. Or less, more preferably 85 ° C. or less. And it is also preferable that temperature difference (DELTA) T (T (A4) -T (A1)) from peak T (A1) to T (A4) is 5 degrees C or less, and it is more preferable that it is 4 degrees C or less.

(V) Method for measuring ethylene content a. Separation of components (A1) and (A2) Based on T (C) determined by the previous TREF measurement, a T (A3) soluble component (A2) was obtained by a temperature rising column fractionation method using a preparative fractionator. ) And T (A3) insoluble component (A1), and the ethylene content of each component is determined by NMR.
The temperature rising column fractionation method is a measurement method disclosed in, for example, Macromolecules; 21, 314 to 319 (1988).

B. Fractionation conditions A cylindrical column having a diameter of 50 mm and a height of 500 mm is filled with a glass bead carrier (80 to 100 mesh) and maintained at 140 ° C. Next, 200 mL of a sample o-dichlorobenzene (ODCB) solution (10 mg / mL) dissolved at 140 ° C. is introduced into the column. Thereafter, the temperature of the column is cooled to 0 ° C. at a rate of temperature decrease of 10 ° C./hour. After holding at 0 ° C. for 1 hour, the column temperature is heated to T (A3) at a heating rate of 10 ° C./hour and held for 1 hour. The accuracy of column temperature control through a series of operations is ± 1 ° C.
Next, 800 mL of o-dichlorobenzene is allowed to flow at a flow rate of 20 mL / min while maintaining the column temperature at T (A3), thereby eluting and recovering components soluble in T (A3) present in the column.
Next, the column temperature is increased to 140 ° C. at a rate of temperature increase of 10 ° C./min, left at 140 ° C. for 1 hour, and then 800 mL of a 140 ° C. solvent (ODCB) is allowed to flow at a flow rate of 20 mL / min to obtain T (A3 ) To elute and collect insoluble components.
The solution containing the polymer obtained by fractionation is concentrated to 20 mL using an evaporator and then precipitated in 5 times the amount of methanol. The precipitated polymer is collected by filtration and dried overnight in a vacuum dryer.

C. Measurement by NMR The ethylene content of each of the components (A1) and (A2) obtained by the above fractionation is determined by analyzing a ¹³ C-NMR spectrum measured according to the following conditions by the proton complete decoupling method. .
Model: GSX-400 manufactured by JEOL Ltd. or equivalent equipment (carbon nuclear resonance frequency of 100 MHz or more) Solvent: o-dichlorobenzene: heavy benzene = 4: 1 (volume ratio) Concentration: 100 mg / mL Temperature: 130 ° C. Pulse angle: 90 ° Pulse interval: 15 seconds Integration count: More than 5,000 times

Spectral assignment may be performed with reference to Macromolecules; 17, 1950 (1984), for example. The attribution of spectra measured under the above conditions is as shown in Table 1 below. Symbols such as S _{alpha alpha} in the table, Carman other; accordance notation (Macromolecules 10,536 (1977)), P represents methyl carbon, S is methylene carbon, T is a methine carbon, respectively.

In the following, when “P” is a propylene unit in a copolymer chain and “E” is an ethylene unit, six types of triads of PPP, PPE, EPE, PEP, PEE, and EEE may exist in the chain. . As described in Macromolecules; 15, 1150 (1982) and the like, the concentration of these triads and the peak intensity of the spectrum are linked by the following relational expressions (1) to (6).
[PPP] = k × I (T _ββ ) (1)
[PPE] = k × I (T _βδ ) (2)
[EPE] = k × I (T _δδ ) (3)
[PEP] = k × I (S _ββ ) (4)
[PEE] = k × I (S _βδ ) (5)
[EEE] = k × {I (S _δδ ) / 2 + I (S _γδ ) / 4} (6)
Here, [] indicates the fraction of triads, for example, [PPP] is the fraction of PPP triads in all triads.
Therefore,
[PPP] + [PPE] + [EPE] + [PEP] + [PEE] + [EEE] = 1 (7)
It is. Further, k is a constant, I indicates spectral intensity, and for example, I (T _ββ ) means the intensity of a peak at 28.7 ppm attributed to T _ββ .
By using the relational expressions (1) to (7) above, the fraction of each triad is obtained, and the ethylene content is obtained from the following expression.
Ethylene content (mol%) = ([PEP] + [PEE] + [EEE]) × 100
The propylene random copolymer of the present invention contains a small amount of propylene heterogeneous bonds (2,1-bonds and / or 1,3-bonds), and thereby the minute amounts described in Table 2 below. A peak is produced.

In order to obtain an accurate ethylene content, it is necessary to take into account the peaks derived from these heterogeneous bonds, but it is difficult to completely separate and identify the peaks derived from heterogeneous bonds. Therefore, the ethylene content of the present invention is the relational expression (1) to (7) as in the analysis of the copolymer produced with a Ziegler-Natta catalyst that does not substantially contain a heterogeneous bond. It is determined using
Conversion from mol% to wt% of ethylene content is performed using the following formula.
Ethylene content (% by weight) = (28 × X / 100) / {28 × X / 100 + 42 × (1−X / 100)} × 100
Here, X is the ethylene content in mol%.
The ethylene content of the entire block copolymer is the weight of each component calculated from the ethylene contents [E] A, [E] B, and TREF of the components (A) and (B) measured above. It is calculated from the ratios W (A) and W (B) [wt%] by the following formula.
[E] W = [E] A × W (A) / 100 + [E] B × W (B) / 100 (wt%)

(3) Metal hydrate component (B)
(I) Metal hydrate Component (B) is a component necessary for exhibiting flame retardancy without generating toxic gas or toxic problems during combustion (at the time of fire), and is used in the present invention. Although it does not specifically limit as a hydrate, For example, the compound which has hydroxyl groups or crystal water, such as aluminum hydroxide, magnesium hydroxide, hydrated aluminum silicate, hydrated magnesium silicate, basic magnesium carbonate, hydrotalcite, etc. It can be used alone or in combination of two or more. Among these metal hydrates, at least one metal hydrate selected from aluminum hydroxide, magnesium hydroxide, or hydrotalcite is preferable. Magnesium hydroxide, aluminum hydroxide, combined use of magnesium hydroxide and hydrotalcite, and combined use of aluminum hydroxide and hydrotalcite are more preferable.

  The metal hydrate is preferably at least partially treated with a silane coupling agent. Examples of the silane coupling agent used for the surface treatment of the metal hydrate include vinyltrimethoxysilane, vinyltriethoxysilane, glycidoxypropyltrimethoxysilane, glycidoxypropyltriethoxysilane, glycidoxypropylmethyldimethoxy. Silane coupling agents having vinyl groups or epoxy groups at the end, such as silane, methacryloxypropyltrimethoxysilane, methacryloxypropyltriethoxysilane, methacryloxypropylmethyldimethoxysilane, mercaptopropyltrimethoxysilane, mercaptopropyltriethoxysilane, etc. Coupling agent having a terminal mercapto group, aminopropyltriethoxysilane, aminopropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopro A crosslinkable silane coupling agent such as a silane coupling agent having an amino group such as pyrtripropyltrimethoxysilane and N- (β-aminoethyl) -γ-aminopropyltripropylmethyldimethoxysilane is preferred. Two or more of these silane coupling agents may be used in combination.

Among such silane coupling agents, silane coupling agents having an epoxy group and / or vinyl group, (meth) acryloyl group, and amino group at the terminal are preferable, and an epoxy group and / or vinyl group at the terminal (meta) ) Those having an acroyl group are preferred. These may be used alone or in combination of two or more.
The metal hydrate treated with the silane coupling agent can be used in combination with an untreated metal hydrate that has not been surface-treated or a metal hydrate treated with another surface treatment agent such as a fatty acid.

As the silane coupling agent surface-treated magnesium hydroxide that can be used in the present invention, non-surface-treated ones (Kisuma 5 (trade name, manufactured by Kyowa Chemical Co., Ltd.), stearic acid, oleic acid, etc. are commercially available. Surface treated with fatty acid (Kisuma 5A (trade name, manufactured by Kyowa Chemical Co., Ltd.)), phosphoric acid ester treated surface treated with the above silane coupling agent, or already with silane coupling agent There are commercially available products of surface-treated magnesium hydroxide (Kisuma 5L, Kisuma 5P (both trade names, manufactured by Kyowa Chemical Co., Ltd.), etc.) and Fine Mag MO-E (trade names, manufactured by TMG).
In addition to the above, a silane coupling having a functional group such as a vinyl group or an epoxy group at its terminal in addition to magnesium hydroxide or aluminum hydroxide whose surface is partially pretreated with a fatty acid or a phosphate ester. It is also possible to use a metal hydrate that has been surface-treated with an agent.

From the viewpoint of dispersibility, aluminum hydroxide and magnesium hydroxide preferably have an average particle size of 0.2 to 4 μm, more preferably 0.2 to 2 μm. Furthermore, a surface treatment may be performed as desired. Examples of the surface treatment agent include stearic acid, a silane coupling agent, a titanate coupling agent, and the like. However, when the surface treatment amount is increased, there is a problem of a decrease in wear resistance, so the content of the treatment agent is preferably 5% by weight or less. Among these, magnesium hydroxide is particularly optimal in terms of practical performance.
The hydrotalcite may be a natural product or a synthetic product. The average particle size of the hydrotalcite is preferably 0.2 to 4 μm, more preferably 0.2 to 2 μm from the viewpoint of dispersibility. Furthermore, a surface treatment may be performed as desired. Examples of the surface treatment agent include stearic acid, a silane coupling agent, a titanate coupling agent, and the like. The hydrotalcite may be a so-called hydrotalcite compound having the same crystal structure as that of hydrotalcite, such as stichtite, pyroolite, leevesite, tacovitite, onesite, iowite.
When aluminum hydroxide or magnesium hydroxide and hydrotalcite are used in combination, the quantity ratio (% by weight, total is 100% by weight) is aluminum hydroxide or magnesium hydroxide: hydrotalcite = 0 to 90:10. To 100, preferably 0 to 88:12 to 100, more preferably 15 to 85:15 to 85. This range is preferable because flame retardancy and wear resistance are remarkably improved.
Moreover, you may mix | blend a red phosphorus, a polyphosphate, a urea compound, a silicone oil, silicone powder, etc. with a flame retardant component (B) as a flame retardant adjuvant as needed.

(Ii) Compounding amount In general, the oxygen index (JIS K7201 3 mm thick sheet) of the flame-retardant molded product is preferably 21 or more, more preferably 23 or more, and further preferably 25 or more, and excellent self-extinguishing properties (difficulty) It is required to have (flammability).
Therefore, the flame retardant component (B) needs to be in the range of 50 to 300 parts by weight, preferably 100 to 200 parts by weight with respect to 100 parts by weight of the polypropylene resin. If the flame retardant component (B) is less than 50 parts by weight, appropriate flame retardancy cannot be obtained, and if it exceeds 300 parts by weight, the desired tensile elongation at break and improvement in bending whitening property cannot be obtained.

(4) Modified polyolefin resin component (C)
(I) Modified polyolefin resin The modified polyolefin resin used in the present invention is an unsaturated carboxylic acid or derivative thereof, (meth) acrylic acid or derivative thereof, epoxy group-containing compound, hydroxyl group-containing compound, amino group-containing compound, or organic silane. A polyolefin resin modified with at least one selected from the group consisting of a compound and an organic titanate compound. Modification includes copolymerization.
Examples of the unsaturated carboxylic acid used for the modification include maleic acid, itaconic acid, fumaric acid and the like. Examples of unsaturated carboxylic acid derivatives include maleic acid monoester, maleic acid diester, maleic anhydride, itaconic acid monoester, itaconic acid diester, itaconic anhydride, fumaric acid monoester, fumaric acid diester, fumaric anhydride, etc. It is done. Examples of (meth) acrylic acid used for the modification include acrylic acid and methacrylic acid. Examples of (meth) acrylic acid derivatives include acrylic acid esters and methacrylic acid esters.

  Epoxy group-containing compounds include glycidyl acrylate, glycidyl methacrylate, itaconic acid monoglycidyl ester, butenetricarboxylic acid monoglycidyl ester, butenetricarboxylic acid diglycidyl ester, butenetricarboxylic acid triglycidyl ester and α-chloroallyl, maleic acid, croton Examples thereof include glycidyl esters such as acid and fumaric acid or glycidyl ethers such as vinyl glycidyl ether, allyl glycidyl ether, glycidyl oxyethyl vinyl ether, and styrene-p-glycidyl ether, and p-glycidyl styrene. Mention may be made of glycidyl methacrylate and allyl glycidyl ether.

  Examples of the hydroxyl group-containing compound include 1-hydroxypropyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and hydroxyethyl (meth) acrylate.

  Examples of the compound containing an amino group include tertiary amino groups such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, and dibutylaminoethyl (meth) acrylate.

  Examples of the organic silane compound include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetylsilane, vinyltrichlorosilane, and the like.

  Examples of the organic titanate compound include tetraisopropyl titanate, tetra-n-butyl titanate, tetrakis (2-ethylhexoxy) titanate, and titanium lactate ammonium.

The content of the functional group-containing compound in the modified polyolefin resin is selected in the range of 0.05 to 10% by mass, preferably 0.1 to 5.0% by mass.
Examples of the polyolefin resin include polypropylene (polypropylene homopolymer, propylene-ethylene random copolymer, propylene-ethylene block copolymer, propylene-α olefin copolymer (α-olefin examples include 1-butene and 1-hexene). , 4-methyl-pentene, etc.), polyethylene (low density polyethylene, high density polyethylene, linear polyethylene), etc. Among them, maleic acid-modified polypropylene is preferable.
A commercially available product can be used as the modified polyolefin resin (C). An example is MODEC CMPP-2 (maleic anhydride modified polypropylene) manufactured by Mitsubishi Chemical Corporation.

(Ii) Blending amount The blending ratio of the modified polyolefin resin component (C) is 1 to 20 parts by weight, preferably 3 to 16 parts by weight, more preferably 5 to 12 parts by weight when the component (A) is 100 parts by weight. Part.
When the blending ratio of (D) exceeds 20 parts by weight, the flexibility is impaired, and it is also disadvantageous for economic efficiency.

(5) Thermoplastic elastomer component (D)
(I) Thermoplastic elastomer Thermoplastic elastomers are generally modifiers for thermoplastic resin materials and are added and added to increase the flexibility and impact resistance of polypropylene resin compositions.
In the present invention, the addition of the thermoplastic elastomer component (D) contributes to an improvement in wear resistance which is contrary to flexibility. As thermoplastic elastomer component (D), styrene / vinyl isoprene block copolymer and hydrogenated product thereof, ethylene / propylene copolymer, ethylene / propylene diene terpolymer copolymer, ethylene / octene copolymer, etc. Examples thereof include a copolymer of ethylene and an α-olefin having ethylene as a main component, a styrene / ethylenebutadiene / styrene copolymer, a hydrogenated product, an isoprene copolymer, and the like. Among these, it is preferable to use a styrene / vinyl isoprene block copolymer from the viewpoint of wear resistance. The MFR of the thermoplastic elastomer component (D) is 0.05 to 15 g / 10 minutes, preferably 1 to 10 g / 10 minutes.

(Ii) Blending amount The blending ratio of the thermoplastic elastomer component (D) is 0 to 100 parts by weight, preferably 0 to 80 parts by weight, more preferably 0 to 60 parts by weight when the component (A) is 100 parts by weight. Part. An amount exceeding 100 parts by weight is disadvantageous for economic efficiency.

3. Production method of composition material of the present invention (1) Production method of composition The flame-retardant polypropylene resin composition in the present invention comprises a propylene-ethylene copolymer component (A) and a metal hydrate component (B). And a modified polyolefin resin component (C), or a thermoplastic elastomer component (D) in addition to these components as an essential component, and if desired, additional components are blended within a range that does not impair the efficacy (action effect) of the present invention. Can be produced by mixing using a known melt-kneading method such as a twin-screw extruder, roll, or Banbury mixer.
For example, after mixing each component at room temperature, it may be produced by melt kneading using a biaxial kneading extruder, or a feed hole is provided in the middle of the kneading extruder, from which metal hydrate is added. You may manufacture by feeding and melt-kneading simultaneously.
In general, the flame-retardant molded article of the present invention uses pellets obtained from the flame-retardant propylene resin composition obtained above, but in the masterbatch method or dry blend method, pellet blending is used. It is also possible to perform molding in such a state, or to perform molding while continuously weighing and weighing using a weight type feeder or the like.

(2) Production Method of Propylene-Ethylene Copolymer Component (A) The propylene-ethylene copolymer component (A) used in the present invention is a propylene / ethylene random copolymer component having a relatively high crystallinity ( A1) and a low-crystalline propylene / ethylene random copolymer component (A2), which are roughly composed of two types of propylene / ethylene random copolymers having different crystallinity, so long as the requirements of the present invention are satisfied. A manufacturing method may be used.
However, since the component (A1) and the component (A2) are different in crystallinity, the melting temperature is also greatly different. When each component is melted and kneaded separately, the component (A2) melts at an extremely early stage, and then the temperature Since the component (A1) is melted after further rising, the inorganic filler is concentrated in the previously melted component (A2), and dispersion failure tends to occur. Therefore, the component (A1) and the component (A2) are most preferably produced by sequential polymerization.

(3) Polymerization method (i) Sequential polymerization of component (A1) and component (A2) In the production of component (A1) and component (A2) of the present invention, component (A1) and component (A2) are sequentially Polymerization is preferred.
At this time, since component (A2) is a copolymer having a high ethylene content and easily sticking alone, component (A2) is polymerized after component (A1) is polymerized in order to prevent problems such as adhesion to the reactor. ) Is preferably used.

When performing sequential polymerization, either a batch method or a continuous method can be used, but it is generally desirable to use a continuous method from the viewpoint of productivity. In the case of a batch method, it is possible to polymerize component (A1) and component (A2) separately using a single reactor by changing the polymerization conditions with time. As long as the efficacy of the present invention is not impaired, a plurality of reactors may be connected in parallel.
In the case of a continuous process, it is necessary to use a production facility in which two or more reactors are connected in series because it is necessary to individually polymerize the component (A1) and the component (A2). A plurality of reactors may be connected in series and / or in parallel for each of the component (A1) and the component (A2).

(Ii) Polymerization process As the polymerization process, any polymerization method such as a slurry method, a bulk method, or a gas phase method can be used. Although supercritical conditions can be used as intermediate conditions between the bulk method and the gas phase method, they are substantially the same as the gas phase method, and are therefore included in the gas phase method without particular distinction.
Here, since the component (A2) having a high ethylene content is easily dissolved in an organic solvent such as hydrocarbon or liquefied propylene, it is desirable to use a gas phase method for producing the component (A2).
Any process may be used for the production of the crystalline propylene-ethylene random copolymer component (A1), but in the case of producing the component (A1) having a relatively low crystallinity, adhesion, etc. In order to avoid this problem, it is desirable to use a vapor phase method.
Therefore, it is most desirable to first polymerize the component (A1) by the bulk method or the gas phase method and then polymerize the component (A2) by the gas phase method using the continuous method.

(Iii) Other polymerization conditions The polymerization temperature can be used without any particular problem as long as it is within a commonly used temperature range. Specifically, a range of 0 to 200 ° C, more preferably 40 to 100 ° C can be used.
The polymerization pressure varies depending on the process to be selected, but it can be used without any problem as long as it is in a pressure range usually used. Specifically, a range of greater than 0 to 200 MPa, more preferably 0.1 to 50 MPa can be used. In that case, inert gas, such as nitrogen, can also coexist.
When the component (A1) is sequentially polymerized in the first step and the component (A2) is sequentially polymerized in the second step, it is desirable to add a polymerization inhibitor to the system in the second step. When a polymerization inhibitor is added to the reactor in which ethylene-propylene random copolymerization in the second step is performed, product quality such as particle properties (fluidity, etc.) and gel of the obtained powder can be improved. Various technical studies have been made on this method, and examples thereof include Japanese Patent Publication No. 63-54296, Japanese Patent Application Laid-Open No. 7-25960, Japanese Patent Application Laid-Open No. 2003-2939, and the like. It is desirable to apply the method to the present invention.

(4) Metallocene-based catalyst Each component must have a narrow crystallinity distribution, that is, a narrow composition distribution. Therefore, Ziegler-Natta type catalysts that have been widely used in the production of polypropylene-based resins are necessary for the present invention. Propylene / ethylene random copolymers that meet the requirements are difficult to produce. Therefore, it is most preferable to use a metallocene catalyst for the production.
The type of the metallocene-based catalyst is not particularly limited as long as it can produce a copolymer having the performance of the present invention. However, in order to satisfy the requirements of the present invention, for example, the following components ( It is preferable to use a metallocene catalyst comprising a) and component (b), and further component (c) used as necessary.
Component (a): At least one metallocene transition metal compound selected from transition metal compounds represented by the following general formula (1) Component (b): Selected from the following (b-1) to (b-4) At least one solid component (b-1) a particulate carrier on which an organoaluminoxy compound is supported (b-2) an ionic property capable of reacting with component (a) to convert component (a) into a cation (B-3) Solid acid fine particles (b-4) Ion exchange layered silicate Component (c): Organoaluminum compound

(I) Component (a)
As the component (a), at least one metallocene transition metal compound selected from transition metal compounds represented by the following general formula (1) can be used.
^{_{Q (C 5 H 4-a}} -aR 1) (C 5 H 4-b -bR 2) MeXY (1)
[Wherein, Q represents a divalent linking group that bridges two conjugated five-membered ring ligands, Me represents a metal atom selected from titanium, zirconium, or hafnium, and X and Y represent hydrogen atoms. Atom, halogen atom, hydrocarbon group, alkoxy group, amino group, nitrogen-containing hydrocarbon group, phosphorous-containing hydrocarbon group or silicon-containing hydrocarbon group, X and Y are each independently, that is, the same or different. Also good. R ¹ and R ² represent hydrogen, hydrocarbon group, halogenated hydrocarbon group, silicon-containing hydrocarbon group, nitrogen-containing hydrocarbon group, oxygen-containing hydrocarbon group, boron-containing hydrocarbon group or phosphorus-containing hydrocarbon group. . a and b are the number of substituents. ]

Specifically, Q represents a divalent linking group that bridges two conjugated five-membered ring ligands. For example, a divalent hydrocarbon group, a silylene group, an oligosilylene group, or a hydrocarbon group as a substituent. Examples thereof include a silylene group or an oligosilylene group, or a germylene group having a hydrocarbon group as a substituent. Among these, preferred is a silylene group having a divalent hydrocarbon group and a hydrocarbon group as a substituent.
X and Y each represents a hydrogen atom, a halogen atom, a hydrocarbon group, an alkoxy group, an amino group, a nitrogen-containing hydrocarbon group, a phosphorus-containing hydrocarbon group, or a silicon-containing hydrocarbon group. And chlorine, methyl, isobutyl, phenyl, dimethylamide, diethylamide group and the like.
R ¹ and R ² represent hydrogen, a hydrocarbon group, a halogenated hydrocarbon group, a silicon-containing hydrocarbon group, a nitrogen-containing hydrocarbon group, an oxygen-containing hydrocarbon group, a boron-containing hydrocarbon group, or a phosphorus-containing hydrocarbon group. . Specific examples of the hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group, a phenyl group, a naphthyl group, a butenyl group, and a butadienyl group. In addition, halogenated hydrocarbon group, silicon-containing hydrocarbon group, nitrogen-containing hydrocarbon group, oxygen-containing hydrocarbon group, boron-containing hydrocarbon group or phosphorus-containing hydrocarbon group include methoxy group, ethoxy group, phenoxy group, trimethylsilyl group. Typical examples include a group, diethylamino group, diphenylamino group, pyrazolyl group, indolyl group, dimethylphosphino group, diphenylphosphino group, diphenylboron group, dimethoxyboron group and the like. Among these, a hydrocarbon group having 1 to 20 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, and a butyl group are particularly preferable.
By the way, adjacent R ¹ and R ² may combine to form a ring, on which a hydrocarbon group, halogenated hydrocarbon group, silicon-containing hydrocarbon group, nitrogen-containing hydrocarbon group, oxygen-containing You may have a substituent which consists of a hydrocarbon group, a boron containing hydrocarbon group, or a phosphorus containing hydrocarbon group.
Me is a metal atom selected from titanium, zirconium and hafnium, preferably zirconium and hafnium.

  Among the components (a) described above, preferred for the production of the propylene polymer of the present invention is a substituted cyclopentadienyl group crosslinked with a silylene group, a germylene group or an alkylene group having a hydrocarbon substituent. A transition metal compound comprising a ligand having a substituted indenyl group, a substituted fluorenyl group, or a substituted azulenyl group, and particularly preferably a 2,4-position-substitution bridged by a silylene group or a germylene group having a hydrocarbon substituent It is a transition metal compound comprising a ligand having an indenyl group and a 2,4-position substituted azulenyl group.

Non-limiting specific examples include dimethylsilylene bis (2-methyl-4-phenylindenyl) zirconium dichloride, diphenylsilylene bis (2-methyl-4-phenylindenyl) zirconium dichloride, dimethylsilylene bis (2-methyl). Benzoindenyl) zirconium dichloride, dimethylsilylenebis {2-isopropyl-4- (3,5-diisopropylphenyl) indenyl} zirconium dichloride, dimethylsilylenebis (2-propyl-4-phenanthrylindenyl) zirconium dichloride, dimethyl Silylenebis (2-methyl-4-phenylazurenyl) zirconium dichloride, dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) azurenyl} zirconium dichloride, dimethylsilylenebi (2-Ethyl-4-phenylazurenyl) zirconium dichloride, dimethylsilylenebis (2-isopropyl-4-phenylazurenyl) zirconium dichloride, dimethylsilylenebis {2-ethyl-4- (2-fluorobiphenyl) azurenyl} zirconium Dichloride, dimethylsilylenebis {2-ethyl-4- (4-t-butyl-3-chlorophenyl) azurenyl} zirconium dichloride, and the like can be given.
A compound in which the silylene group of the compound of these specific examples is replaced with a germylene group and zirconium is replaced with hafnium is also exemplified as a suitable compound.
In addition, since the catalyst component is not an important element of the present invention, it avoids complicated listing and is limited to a representative example, but it is obvious that the effective range of the present invention is not limited thereby. It is.

(Ii) Component (b)
As the component (b), at least one solid component selected from the components (b-1) to (b-4) described above is used. Each of these components is known and can be used by appropriately selecting from known techniques. Specific examples and manufacturing methods thereof are described in detail in JP-A No. 2002-284808, JP-A No. 2002-53609, JP-A No. 2002-69116, JP-A No. 2003-105015, and the like.
Here, as the particulate carrier used for the component (b-1) and the component (b-2), inorganic oxides such as silica, alumina, magnesia, silica alumina, silica magnesia, magnesium chloride, magnesium oxychloride, chloride Examples thereof include inorganic halides such as aluminum and lanthanum chloride, and porous organic carriers such as polypropylene, polyethylene, polystyrene, styrene divinyl benzene copolymer, and acrylic acid copolymer.

As a non-limiting specific example of the component (b), as the component (b-1), a fine particle carrier on which methylalumoxane, isobutylalumoxane, methylisobutylalumoxane, aluminum butylboronate tetraisobutyl or the like is supported, As component (b-2), triphenylborane, tris (3,5-difluorophenyl) borane, tris (pentafluorophenyl) borane, triphenylcarbonium tetrakis (pentafluorophenyl) borate, N, N-dimethylanilinium Particulate carrier carrying tetrakis (pentafluorophenyl) borate, etc. as component (b-3), alumina, silica alumina, magnesium chloride, etc. as component (b-4), montmorillonite, zakonite, beidellite, non Tronite, Sa Knight, hectorite, stevensite, bentonite, smectite group such as taeniolite, vermiculite, and the like mica group. These may form a mixed layer.
Particularly preferred among the above components (b) is the ion-exchange layered silicate of component (b-4), and more preferred are chemical treatments such as acid treatment, alkali treatment, salt treatment, and organic matter treatment. It is an ion exchange layered silicate applied.

(Iii) Component (c)
Examples of organoaluminum compounds used as component (c) as needed are:
General formula AlR _a X _3-a
(Wherein R is a hydrocarbon group having 1 to 20 carbon atoms, X is hydrogen, halogen, alkoxy group, a is a number of 0 <a ≦ 3), trimethylaluminum, triethylaluminum, tripropylaluminum, Trialkylaluminum such as triisobutylaluminum or halogen- or alkoxy-containing alkylaluminum such as diethylaluminum monochloride, diethylaluminum monomethoxide. In addition, aluminoxanes such as methylaluminoxane can also be used. Of these, trialkylaluminum is particularly preferred.

(Iv) Formation of catalyst Component (a) and component (b) are further brought into contact with component (c) as necessary to form a catalyst. The contact method is not particularly limited, but the contact can be made in the following order. Moreover, this contact may be performed not only at the time of catalyst preparation but also at the time of prepolymerization with olefin or at the time of polymerization of olefin.
1) Contact component (a) and component (b) 2) Add component (c) after contacting component (a) and component (b) 3) Contact component (a) and component (c) 4) Add component (b) after contact 4) Add component (a) after contacting component (b) and component (c) 5) Contact three components simultaneously

The amount of components (a), (b) and (c) used in the present invention is arbitrary. For example, the amount of component (a) used relative to component (b) is preferably in the range of 0.1 μmol to 1,000 μmol, particularly preferably 0.5 μmol to 500 μmol, relative to 1 g of component (b). The amount of component (c) used relative to component (b) is preferably such that the amount of aluminum metal is 0.001 to 100 mmol, particularly preferably 0.005 to 50 mmol, relative to 1 g of component (b). Therefore, the amount of the component (c) relative to the component (a) is preferably in the range of 10 ⁻³ to 10 ⁶ , particularly preferably in the range of 10 ⁻² to 10 ⁵ , in terms of the molar ratio of the metal.

(V) Prepolymerization treatment The catalyst of the present invention is preferably subjected to a prepolymerization treatment comprising preliminarily contacting an olefin and polymerizing a small amount. The olefin to be used is not particularly limited, but ethylene, propylene, 1-butene, 1-hexene, 1-octene, 4-methyl-1-pentene, 3-methyl-1-butene, vinylcycloalkane, styrene and the like can be used. In particular, it is preferable to use propylene.
The olefin can be supplied by any method such as a supply method for maintaining the olefin at a constant speed or in a constant pressure state, a combination thereof, or a stepwise change.
The prepolymerization temperature and time are not particularly limited, but are preferably in the range of −20 ° C. to 100 ° C. and 5 minutes to 24 hours, respectively.
The prepolymerization amount is preferably 0.01 to 100 parts, more preferably 0.1 to 50 parts, based on the component (b).
After completion of the prepolymerization, the catalyst can be used as it is, depending on the usage form of the catalyst. However, if necessary, drying can be performed.
Furthermore, a polymer such as polyethylene, polypropylene, or polystyrene, or an inorganic oxide solid such as silica or titania can be allowed to coexist during or after the contact of the above components.

4). Additional component An additional component can be mix | blended with the flame-retardant polypropylene-type resin composition of this invention in order to provide another characteristic in the range which does not impair the effect of this invention. For example, heat stabilizer, antioxidant, weather stabilizer, ultraviolet absorber, crystal nucleating agent, copper damage inhibitor, antistatic agent, slip agent, anti-blocking agent, antifogging agent, colorant, filler, metal An inert agent, a process oil, a petroleum resin, an antibacterial agent, an anti-anticide, a plasticizer, carbon black, and the like can be blended.

5). Use and molding method of the present invention As the use of the flame-retardant molded body of the present invention, a self-extinguishing molded body is particularly suitable, but is not limited thereto, for example, wire coating, steel pipe coating, steel wire coating, Examples include the field of coated extruded products such as cable coating, construction / civil engineering industrial materials, parts of household electrical appliances, and automobile parts.
The flame-retardant molded product of the present invention can be preferably produced, for example, by coating extrusion molding and / or profile extrusion molding of a flame-retardant polypropylene resin composition.
Examples of the coated extrusion-molded body include electric wire coating, steel pipe coating, steel wire coating, and cable coating.
In addition, various molding methods such as injection molding and compression molding are used for various flame-retardant molded products.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples unless it exceeds the gist. The measurement methods and materials used in this example are as follows.

I. Measurement method and evaluation method 1) Melt flow rate (MFR)
According to JIS K7210 A method condition M, it measured on condition of the following.
Test temperature: 230 ° C Nominal load: 2.16kg Die shape: Diameter 2.095mm Length 8.00mm

2) TREF
(Create elution curve)
According to the method described above.
〔apparatus〕
(TREF part)
TREF column: 4.3 mmφ × 150 mm stainless steel column Column packing material: 10
0μm surface inactive treated glass beads Heating method: Aluminum heat block Cooling method: Peltier element (Peltier element is cooled by water) Temperature distribution: ± 0.5 ° C Temperature controller: Chino Digital Program Controller KP1000 Valve oven) Heating method: Air bath oven Measurement temperature: 140 ° C Temperature distribution: ± 1 ° C Valve: 6-way valve, 4-way valve (sample injection part)
Injection method: Loop injection method Injection amount: Loop size, 0.1 ml Inlet heating method: Aluminum heat block Measurement temperature: 140 ° C
(Detection unit)
Detector: Fixed wavelength type infrared detector FOXBORO, MIRAN 1A Detection wavelength:
3.42 μm High-temperature flow cell: LC-IR micro flow cell Optical path length 1.5 mm
Window shape 2φ × 4mm long round, synthetic sapphire window Measurement temperature: 140 ℃
(Pump part)
Liquid feed pump: manufactured by Senshu Kagaku Co., Ltd., SSC-3461 pump [measurement conditions]
Solvent: o-dichlorobenzene (containing 0.5 mg / mL BHT) Sample concentration: 5 mg / mL Sample injection volume: 0.1 mL Solvent flow rate: 1 mL / min

3) Measurement of solid viscoelasticity A sample cut into a strip of 10 mm width × 18 mm length × 2 mm thickness from a 2 mm thick sheet injection molded under the following conditions was used. The apparatus used was ARES manufactured by Rheometric Scientific. The frequency is 1 Hz. The measurement temperature was raised stepwise from −60 ° C., and the measurement was performed until the sample melted and became impossible to measure. The strain was performed in the range of 0.1 to 0.5%.
[Preparation of specimen]
Standard number: JIS-7152 (ISO294-1) Molding machine: TU-15 injection molding machine manufactured by Toyo Machine Metal Co., Ltd. Molding machine set temperature: 80, 80, 160, 200, 200, 200 ° C. from under the hopper Mold temperature: 40 ° C Injection speed: 200 mm / s (speed in the mold cavity) Injection pressure: 800 kgf / cm ² Holding pressure: 800 kgf / cm ²
Holding time: 40 seconds Mold shape: Flat plate (thickness 2 mm, width 30 mm, length 90 mm)

4) DSC
Using a Seiko DSC, take 5.0 mg of sample, hold at 200 ° C. for 5 minutes, crystallize to 40 ° C. at a rate of temperature decrease of 10 ° C./min, and further melt at a rate of temperature increase of 10 ° C./min. The melting peak temperature was Tm (unit: ° C.). DHm was determined from the area of the endothermic curve at the time of temperature increase.

5) Oxygen index According to the method described above.

6) Calculation of ethylene content According to the method described above.

7) Evaluation of tensile elongation at break In the evaluation of tensile elongation at break of the wire-coated extruded product, a coated wire with a length of 150 mm was used, the core wire was pulled out and only the coated layer was taken out and used as a sample. It is performed at a speed of 50 mm / min. The tensile elongation at break is calculated by the following formula based on the rate of change of the distance between the grippers at the breaking point.
Elongation at break = (distance between grips at break point−100) / 100 × 100 [%]

8) Oxygen index (conforming to JIS K7201)
The composition pellets were press-molded (preheated at 200 ° C. for 7 minutes, taken out after 3 minutes at 2 Ma pressure, and cooled at 30 ° C. and 13 Ma for 3 minutes), and the specimen shape IV (hot press) was used using a 3 mm thick press sheet Product; 3 mm thick sheet) sample was prepared, the oxygen index was measured in accordance with JIS K7201, and evaluated according to the following criteria.
Flame retardance pass: Oxygen index 21 or more Flame retardance: Oxygen index less than 21

9) Flexibility (based on JIS K7203 flexural modulus)
A test piece having a thickness of 4 mm, a length of 90 mm, and a width of 10 mm was prepared by using an injection molding machine (Japanese steel 150t injection molding machine, resin temperature 200 ° C., mold cooling temperature 30 ° C. cooling 30 seconds) using the composition pellets. And used for evaluation. The flexural modulus was measured according to JIS K7203 and evaluated according to the following criteria.
Good: 1500 MPa or less Defect: Over 1500 MPa

II. Material 1) Propylene-ethylene copolymer component (A)
[Polymer Production Example A-1]
(Preparation of prepolymerization catalyst)
Silicate chemical treatment: To a glass separable flask with a 10 liter stirring blade, 3.75 liters of distilled water was added slowly followed by 2.5 kg of concentrated sulfuric acid (96%). At 50 ° C., 1 kg of montmorillonite (Menzawa Chemical Co., Ltd. Benclay SL; average particle size = 25 μm, particle size distribution = 10-60 μm) was dispersed, heated to 90 ° C., and maintained at that temperature for 6.5 hours. After cooling to 50 ° C., the slurry was filtered under reduced pressure to recover the cake. 7 liters of distilled water was added to this cake to reslurry it, and then filtered. This washing operation was performed until the pH of the washing solution (filtrate) exceeded 3.5. The collected cake was dried at 110 ° C. overnight under a nitrogen atmosphere. The weight after drying was 707 g.

(Drying of silicate) The silicate previously chemically treated was dried by a kiln dryer. Specifications and drying conditions are as follows.
Rotating cylinder: Cylindrical, inner diameter 50 mm, heating zone 550 mm (electric furnace) Number of rotations with lifting blade: 2 rpm Tilt angle: 20/520 Silicate feed rate: 2.5 g / min Gas flow rate: Nitrogen 96 liters / hour Counter-current drying temperature: 200 ° C (powder temperature)

(Preparation of catalyst) An autoclave having an internal volume of 16 liters having a stirring and temperature control device was sufficiently replaced with nitrogen. 200 g of dry silicate was introduced, 1,160 ml of mixed heptane, 840 ml of a heptane solution of triethylaluminum (0.60M) were added, and the mixture was stirred at room temperature. After 1 hour, the mixture was washed with mixed heptane to prepare 2,000 ml of silicate slurry. Next, 9.6 ml of a heptane solution of triisobutylaluminum (0.71 M / L) was added to the silicate slurry prepared above and reacted at 25 ° C. for 1 hour. In parallel, 270 ml of (r) -dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4H-azulenyl}] zirconium and 2,180 mg (0.3 mM) of mixed heptane Then, 33.1 ml of a heptane solution of triisobutylaluminum (0.71 M) was added, and the mixture reacted at room temperature for 1 hour was added to the silicate slurry. After stirring for 1 hour, 5,000 ml was added with mixed heptane. Prepared.

(Preliminary polymerization) Subsequently, the temperature in the tank was raised by 40 ° C., and when the temperature was stabilized, propylene was supplied at a rate of 100 g / hour to maintain the temperature. After 4 hours, the supply of propylene was stopped and maintained for another 2 hours. After completion of the prepolymerization, the residual monomer was purged, stirring was stopped and the mixture was allowed to stand for about 10 minutes, and then the supernatant was decanted to 2,400 ml. Subsequently, 9.5 ml of a heptane solution of triisobutylaluminum (0.71 M / L) and 5,600 ml of mixed heptane were further added, stirred for 30 minutes at 40 ° C., allowed to stand for 10 minutes, and then 5,600 ml of the supernatant was removed. It was. This operation was further repeated 3 times. When the component analysis of the final supernatant was conducted, the concentration of the organoaluminum component was 1.23 mmol / L and the Zr concentration was 8.6 × 10 ⁻⁶ g / L, and the abundance in the supernatant with respect to the amount charged. Was 0.016%. Subsequently, 170 ml of a heptane solution of triisobutylaluminum (0.71 M / L) was added, followed by drying at 45 ° C. under reduced pressure. A prepolymerized catalyst containing 2.0 g of polypropylene per 1 g of catalyst was obtained.
Using this prepolymerized catalyst, a propylene-ethylene copolymer was produced according to the following procedure.

(First step) Propylene-ethylene random copolymerization was carried out using a liquid phase polymerization tank equipped with a stirrer having an internal volume of 0.4 m ³ . Liquefied propylene, liquefied ethylene, and triisobutylaluminum were continuously fed at 90 kg / hour, 4.2 kg / hour, and 21.2 g / hour, respectively. The hydrogen supply amount was adjusted so that the MFR in the first step became a target value. Further, the above prepolymerized catalyst was supplied as a catalyst (excluding the weight of the prepolymerized polymer) so as to be 6.9 g / hour. The polymerization tank was cooled so that the polymerization temperature was 45 ° C.
When the propylene-ethylene random copolymer obtained in the first step was analyzed, BD (bulk density) was 0.46 g / cc, MFR was 7.0 g / 10 min, and ethylene content was 3.7 wt%. .

(Second step) Propylene-ethylene random copolymerization was carried out using a stirred gas phase polymerization tank having an internal volume of 0.5 m ³ . The slurry containing polymer particles was continuously extracted from the liquid phase polymerization tank in the first step, and after liquefied propylene was flushed, the pressure was increased with nitrogen and continuously supplied to the gas phase polymerization tank. The polymerization tank was controlled so that the temperature was 80 ° C. and the total partial pressure of propylene, ethylene and hydrogen was 1.5 MPa. At that time, the concentration of propylene, ethylene and hydrogen in the total partial pressure of propylene, ethylene and hydrogen was controlled to be 66.97 vol%, 32.99 vol% and 420 volppm, respectively. Furthermore, ethanol was supplied to the gas phase polymerization tank as an activity inhibitor. The supply amount of ethanol was set to 0.3 mol / mol with respect to aluminum in triisobutylaluminum supplied accompanying the polymer particles supplied to the gas phase polymerization tank.
When the obtained propylene-ethylene copolymer was analyzed, the activity was 8.7 kg / g-catalyst, BD was 0.41 g / cc, MFR was 7.0 g / 10 min, and the ethylene content was 8.7 wt%. Met.

The resulting propylene-ethylene copolymer (PP-1) was measured for MFR, TREF, NMR (ethylene content), DMA, DSC, GPC, and solid viscoelasticity. Table 3 shows the data obtained by the measurement.
From the obtained measurement results, PP-1 has one peak due to glass transition observed in the temperature range of −60 to 20 ° C., the peak temperature is −16.4 ° C., and 2 in the TREF elution curve. Two peaks were observed. From the above, it can be said that PP-1 satisfies all the requirements as the propylene-ethylene copolymer component (A) of the present invention.

[Polymer Production Example A-2]
(Preparation of supported solid catalyst component)
75 ml of purified heptane, 75 ml of titanium tetrabutoxide, and 10 g of anhydrous magnesium chloride are added to a glass three-necked flask with a nitrogen-substituted inner volume 500 ml thermometer and stirring rod, and then the flask is heated to 90 ° C. The anhydrous magnesium chloride was completely dissolved over 2 hours. Next, the flask was cooled to 40 ° C., and 15 ml of methylhydropolysiloxane was added to precipitate a magnesium chloride / titanium tetrabutoxide complex. This was washed with purified heptane to obtain an off-white precipitated solid. 65 ml of the resulting heptane slurry containing 20 g of the precipitated solid was put into a glass three-necked flask with a 300 ml thermometer and a stirring rod with a nitrogen purge, and then 25 ml of a heptane solution containing 8.7 ml of silicon tetrachloride was added. It added over 30 minutes at room temperature, and was then made to react at 30 degreeC for 30 minutes. Furthermore, it was made to react at 90 degreeC for 1 hour, and it wash | cleaned by the refinement | purification heptane after completion | finish of reaction. Next, 50 ml of a heptane solution containing 1.6 ml of phthaloyl chloride was added and reacted at 50 ° C. for 2 hours. This was washed again with purified heptane, and further 25 ml of titanium tetrachloride was added and reacted at 90 ° C. for 2 hours. Was washed with purified heptane to obtain a supported solid catalyst component. The titanium content of the supported solid catalyst component was 3.22% by weight.

(Production of propylene / ethylene block copolymer (component (A))
After sufficiently replacing the stirred autoclave with an internal volume of 200 liters with propylene, 60 liters of dehydrated and deoxygenated n-heptane was introduced, and further 15.0 g of triethylaluminum, 3.0 g of the supported solid catalyst component and Tertiary butylmethyldimethoxysilane (4.3 g) was introduced at 70 ° C. in a propylene atmosphere. The first stage polymerization was started by heating the autoclave to 75 ° C. and then feeding propylene at a rate of 9 kg / hour while maintaining the hydrogen concentration at 13%. After 228 minutes, the propylene feed was stopped and the polymerization was continued at 75 ° C. for 90 minutes. Vapor phase propylene was purged to 0.2 kg / cm ² G. Next, after adding 4.9 g of n-butanol and lowering the temperature of the autoclave to 60 ° C., the second stage polymerization is fed at a rate of 2.58 kg / hour of propylene and 1.72 kg / hour of ethylene for 53 minutes. It carried out by.
The slurry thus obtained was filtered and dried to obtain a powdery propylene / ethylene block copolymer (PP-2). The physical properties of the copolymer are as shown in Table 3. PP-2 has two peaks due to glass transition observed in the temperature range of −60 to 20 ° C., the peak temperatures are −36 ° C. and 4 ° C., and two peaks are observed in the TREF elution curve. It was. From the above, it can be said that PP-2 does not satisfy the requirements as the propylene-ethylene copolymer component (A) of the present invention.

2) Metal hydrate component (B)
B-1: Magnesium hydroxide (Kisuma-5A manufactured by Kyowa Chemical)
B-2: Hydrotalcite (DHT4A manufactured by Kyowa Chemical)

3) Modified polyolefin resin component (C)
C-1: Maleic anhydride-modified polypropylene (Madek CMPP-2 manufactured by Mitsubishi Chemical)

4) Thermoplastic elastomer component (D)
D-1: Hydrogenated product of styrene / vinyl isoprene block copolymer (Hibura 7311 MFR 2 g / 10 min, manufactured by Kuraray Co., Ltd.)

[Example 1]
100 parts by weight of B-1 magnesium hydroxide as a component (B) with respect to 100 parts by weight of the propylene-ethylene copolymer (PP-1) obtained in Production Example A-1 as a component (A) As (C), 5 parts by weight of C-1 was added, and the following ingredients were added as additives.
Dispersant: 0.3 parts by weight of magnesium stearate (reagent grade 1) Antioxidant 1: Tris (2,4-di-t-butylphenyl) phosphite (Ciba Specials Chemical Co., Ltd., Irgaphos 168) 2 parts by weight Antioxidant 2: Tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4-hydroxyphenyl) propionate] methane (Ciba Specials Chemical Co., Ltd., Irganox 1010) 1 part by weight Antioxidant 3: 0.2 part by weight of dimyristyl thiodipropionate (Sumitomo Chemical Co., Ltd., Sumitizer TPD) These are blended using a super mixer and melted under the following conditions using a twin screw extruder It knead | mixed and the polypropylene-type resin composition pellet was obtained. Table 4 shows the formulation and various evaluation results.

  Melting and kneading equipment: Kobe Steel, NCM60 Chamber temperature: 200 ° C. Rotor rotation speed: 500 rpm Resin temperature: 200 ° C. Screw rotation speed of extruder: 25 rpm

[Examples 2 to 4]
Granulation, molding and evaluation under the same conditions as in Example 1 except that the blending ratio of component (B), component (C) and component (D) is changed as shown in Table 4. Went. Table 4 shows the formulation and various evaluation results.

[Comparative Examples 1-4]
Granulation, molding, and evaluation under the same conditions as in Example 1, except that the blending ratio of component (A), component (B), and component (C) is changed as shown in Table 5. Went. Table 5 shows the formulation and various evaluation results.

[Consideration of results of Examples and Comparative Examples]
In Examples 1 to 4, which satisfy all the requirements of the present invention, the oxygen index is all acceptable, showing very good flame retardancy, and the tensile elongation at break is all 400% or more, which is particularly excellent tensile properties. It is excellent in flexibility, and the electric wire covering characteristics are pushed, and the result is good.
On the other hand, in Comparative Example 1, since the glass transition peak temperature of the thermoplastic resin as the main agent is high, the tensile elongation at break is poor and the flexibility is poor. In Comparative Example 2, since the modified polyolefin component was not added, the tensile elongation at break was slightly inferior to that of the example. Comparative Example 3 is inferior in flexibility due to the large amount of the modified polyolefin component. In Comparative Example 4, the amount of the metal hydrate which is a flame retardant is excessive and deviates from the requirements of the present invention, the tensile elongation at break is lowered, and the flexibility is also inferior.
From the data of each of the above examples and the comparison results with each comparative example, the flame retardant polypropylene resin composition of the present invention is very excellent in each performance while maintaining flame retardancy than conventional materials. It is clear that the rationality and significance of the requirements that make up the present invention have been demonstrated, as well as the superiority over the prior art.

  According to the present invention, a large amount of an inorganic flame retardant that does not cause the generation of toxic gas during combustion (at the time of a fire) and that does not bleed out the flame retardant, sufficiently increases the flame retardancy of the thermoplastic resin. However, it has excellent mechanical resin performance (particularly tensile strength), improved whitening resistance against external forces (resistance to whitening phenomenon of bent parts of products due to external force) and wear resistance, and good Highly flame-retardant (self-extinguishing) thermoplastic resin material for moldings that has excellent flexibility and moldability can be obtained, and flame-retardant moldings using this can be used in a wide range of fields. Its industrial utility is very high.

Claims (7)

100 parts by weight of a propylene-ethylene copolymer component (A) having the following characteristics (i) to (ii), 50 to 300 parts by weight of a metal hydrate component (B), and a modified polyolefin resin component (C) 1 to 20 parts by weight and a thermoplastic elastomer component (D) 0 to 100 parts by weight are blended, and a flame retardant polypropylene resin composition.
(I) In the temperature-loss tangent (tan δ) curve obtained by solid viscoelasticity measurement (DMA), the peak due to the glass transition observed in the temperature range of −60 to 20 ° C. is a single peak. (Ii) plot of elution amount (dwt% / dT) against temperature by temperature rising elution fractionation method (TREF) in the temperature range of −15 ° C. to 140 ° C. using an o-dichlorobenzene solvent. In the TREF elution curve obtained as follows, the following characteristics (ii-A) to (ii-C) have been observed. (Ii-A) Two peaks are observed in the elution curve, and peak T (A1) observed on the high temperature side Is in the range of 65 to 95 ° C., and the peak T (A2) observed on the low temperature side is 45 ° C. or less. (Ii-B) The temperature T () between the T (A1) and T (A2) peaks. By A3) The amount W (A2) of the component (A2) to be eluted is 5 to 70 wt%, and the component is a propylene / ethylene random copolymer containing 6 to 15 wt% of ethylene (ii-C) by T (A3) The amount W (A1) of the component (A1) to be eluted after elution of the component to be eluted is 95 to 30 wt%, and the component is a propylene homopolymer or propylene / ethylene random copolymer containing 0 to 6 wt% of ethylene. The flame-retardant polypropylene resin composition according to claim 1, wherein the propylene-ethylene copolymer component (A) further has the following characteristics (iii).
(Iii) 95-30 wt% of a crystalline propylene homopolymer component or a crystalline propylene-ethylene random copolymer component (A1) having an ethylene content of 0-6 wt% in the first step using a metallocene catalyst; It is obtained by sequentially polymerizing 5-70 wt% of a low crystalline propylene-ethylene random copolymer component (A2) having an ethylene content of 6-15 wt% in two steps. The flame-retardant polypropylene resin composition according to claim 1 or 2, wherein the propylene-ethylene copolymer component (A) further has the following characteristics (iv).
(Iv) In a TREF elution curve obtained as a plot of elution amount (dwt% / dT) against temperature by a temperature rising elution fractionation method (TREF) in a temperature range of −15 ° C. to 140 ° C. using an o-dichlorobenzene solvent. The following characteristics (iv-A) to (iv-D) have been observed: (iv-A) Two peaks are observed in the elution curve, and the peak T (A1) observed on the high temperature side is in the range of 65 to 88 ° C. The peak T (A2) observed on the low temperature side is 45 ° C. or lower. (Iv-B) A component that elutes up to the temperature T (A3) at the midpoint between both T (A1) and T (A2) peaks. The amount of (A2) W (A2) is 30 to 70 wt%, and the component is a propylene / ethylene random copolymer containing 8 to 14 wt% of ethylene (iv-C) A component that elutes by T (A3) Elution after elution The amount W (A1) of the component (A1) is 70 to 30 wt%, and the component is a propylene / ethylene random copolymer containing 1 to 5 wt% of ethylene. (Iv-D) Temperature T at which 99 wt% is eluted (A4) is 90 ° C. or lower, and the temperature difference ΔT (T (A4) −T (A1)) from the peak T (A1) to T (A4) is 5 ° C. or lower.   The flame retardant polypropylene system according to any one of claims 1 to 3, wherein the metal hydrate component (B) is at least one selected from aluminum hydroxide, magnesium hydroxide or hydrotalcite. Resin composition.   The flame-retardant polypropylene resin composition according to any one of claims 1 to 4, wherein the flame-retardant polypropylene resin composition is used for a self-extinguishing molded body.   The molded object formed by shape | molding the flame-retardant polypropylene resin composition in any one of Claims 1-5.   An extruded product, wherein the molded product according to claim 6 is produced by extrusion molding.