JPH1017733A - Polypropylene resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polypropylene having excellent rigidity, low molding shrinkage, good dimensional stability and good moldability even if a large amount of an inorganic filler is blended, without deterioration in tensile elongation characteristics. A resin composition is provided. SOLUTION: The polypropylene-based resin composition comprising a polypropylene-based resin and an inorganic filler, wherein the polypropylene-based resin has an elution amount at 0 ° C. or lower in a cross fractionation chromatograph of 10 to 60% of the total elution amount. %, The elution amount exceeding 0 ° C. and less than 90 ° C. is 10 to 85% by weight of the total elution amount, and the elution amount at 90 ° C. or more is 5 to 50% by weight of the total elution amount. %, And the inorganic filler is the polypropylene resin 10
A polypropylene-based resin composition mixed with 50 to 900 parts by weight based on 0 part by weight.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for producing a rubber composition which is excellent in rigidity even if a large amount of an inorganic filler is blended.
The present invention relates to a polypropylene resin composition having a small molding shrinkage, good dimensional stability and good moldability.

[0002]

2. Description of the Related Art By blending an inorganic filler with a polyolefin, physical properties such as rigidity and molding shrinkage are improved.
BACKGROUND ART Resin compositions for which cost is reduced are widely used for various applications. As such a polyolefin-based resin composition, for example, JP-A-60-69145,
A polyolefin blended with an inorganic filler having specific physical properties is disclosed.

The content of the inorganic filler in these conventional polyolefin resin compositions is about 40% by weight (about 66 parts by weight of the inorganic filler per 100 parts by weight of the polyolefin).
Is the limit. With such a compounding amount, the improvement of the physical properties and the cost reduction effect by the compounding of the inorganic filler are not sufficient. On the other hand, when a larger amount of the inorganic filler is blended, the tensile elongation characteristics are significantly reduced. For this reason, a sheet obtained from a polyolefin-based resin composition containing a large amount of an inorganic filler tends to be broken and cannot be used as a sheet material. In addition, impact resistance, particularly cold impact resistance, is deteriorated due to a decrease in tensile elongation characteristics, and thus it is not suitable as a master batch of an injection molding material.

[0004]

In view of the above, the present invention has been made in view of the above, even if a large amount of inorganic filler is blended, the tensile elongation characteristics are not reduced, the rigidity is excellent, the molding shrinkage is small,
An object of the present invention is to provide a polypropylene-based resin composition having good dimensional stability and moldability.

[0005]

The present invention relates to a polypropylene resin composition comprising a polypropylene resin and an inorganic filler, wherein the polypropylene resin has an elution amount of 0 ° C. or less in a cross fractionation chromatograph. But,
10 to 60% by weight of the total eluted amount, the elution amount exceeding 0 ° C and less than 90 ° C is 10 to 85% by weight of the total eluted amount, and the elution amount at 90 ° C or more is 5 to elution amount
The inorganic filler is 50 to 9 parts by weight based on 100 parts by weight of the polypropylene resin.
It is a polypropylene resin composition blended in an amount of 00 parts by weight. Hereinafter, the present invention will be described in detail.

The polypropylene resin used in the present invention has an elution amount at 0 ° C. or less of 10 to 60% by weight of the total elution amount in a cross fractionation chromatograph.
The elution amount above 0 ° C. and below 90 ° C. is 10 to 85% by weight of the total elution amount, and the elution amount above 90 ° C.
It is 5 to 50% by weight of the total elution amount. The difference in elution temperature mainly indicates the difference in crystallinity. That is, the polypropylene-based resin has a wide crystallinity distribution. By using such a polypropylene-based resin, a large amount of inorganic filler can be compounded.

[0007] The cross separation method using the above-mentioned cross separation chromatograph is generally carried out as follows. The polypropylene-based resin is dissolved in o-dichlorobenzene at a temperature at which the polypropylene-based resin completely dissolves, and the solution is cooled at a constant rate to form a thin polymer phase on the surface of the previously prepared inert carrier. Next, the temperature is increased continuously or stepwise, the concentration of the components eluted sequentially in each predetermined temperature range is detected, and the temperature increase elution fractionation for measuring the composition distribution (crystallinity distribution) is performed. The molecular weight and molecular weight distribution of the components are measured by high-temperature GPC.
As the above-mentioned cross fractionation chromatography, for example, CF
C-150A (manufactured by Mitsubishi Yuka) or the like can be used.

In the present invention, the elution amount of the polypropylene-based resin in each temperature range using the above-mentioned cross fractionation chromatograph was specifically measured as follows. The polypropylene resin was completely dissolved in a 140 ° C. o-dichlorobenzene solution, and cooled to 0 ° C. over 24 hours in the presence of a silicon carrier. The polypropylene resin remaining in the solution, which did not precipitate at 0 ° C., was eluted as a component eluting at 0 ° C. or lower, and the elution amount was measured. next,
The surface of the carrier on which the polypropylene resin is deposited on the surface is o-
The temperature was raised to 140 ° C. at a rate of 2 ° C./min while flowing dichlorobenzene, and the eluted components of the polypropylene resin in each temperature range were measured as the amount of elution at every 2 ° C.

The above polypropylene resin has an elution amount at 0 ° C. or less of 10 to 60% by weight of the total elution amount. 10
When the amount is less than 10% by weight, the flexibility of the polypropylene resin is inferior, so that a large amount of the inorganic filler cannot be compounded.
If the content exceeds 0% by weight, the polypropylene resin is too soft and difficult to handle, so the content is limited to the above range.
Preferably, it is 30 to 55% by weight.

The above-mentioned polypropylene resin has an elution amount exceeding 0 ° C. and less than 90 ° C., which is 10 to 10% of the total elution amount.
85% by weight. When the content is less than 10% by weight, the material has poor adhesion between the high crystallinity portion and the low crystallinity portion.
If the content exceeds 5% by weight, the material becomes inferior in both heat resistance and flexibility, so that the content is limited to the above range.

The above polypropylene resin has an elution amount at 90 ° C. or more of 5 to 50% by weight of the total elution amount. When the amount is less than 5% by weight, the heat resistance of the obtained polypropylene resin composition is remarkably inferior. When the amount is more than 50% by weight, the polypropylene resin becomes too hard to mix a large amount of inorganic filler. It is limited to the above range.
Preferably, it is 10 to 40% by weight.

The above-mentioned polypropylene-based resin is not particularly restricted but includes, for example, homopolypropylene such as atactic polypropylene; and copolymers of propylene and α-olefin. As the α-olefin,
There is no particular limitation as long as it is other than propylene, and examples include ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene and the like.

Specific examples of the copolymer of propylene and α-olefin are not particularly limited. For example, binary copolymers of propylene / ethylene, propylene / 1-butene, propylene / 4-methyl-1-pentene, etc. Polymer: Ternary copolymers such as propylene / ethylene / 1-butene and propylene / 1-butene / 4-methyl-1-pentene are exemplified.

In the present invention, the polypropylene resin is a copolymer composed of propylene and at least one α-olefin different from propylene, which is polymerized by multi-stage polymerization. A polymer obtained by polymerizing propylene or copolymerizing propylene and an α-olefin in the first stage can be more preferably used.

As a method of polymerizing propylene or copolymerizing propylene and an α-olefin in the first stage, the first stage includes a method in which propylene gas or propylene is mixed with α-olefin.
Polymerization or copolymerization is performed in a mixed gas of olefins, and then a mixed gas of propylene and α-olefin is supplied,
Further, there may be mentioned a method of performing copolymerization. When the first-stage polymerization is carried out in a mixed gas of propylene and α-olefin, generally, a mixed gas having a high propylene content in the first stage is mixed with an α-olefin content gas in the second and subsequent stages. Use a large amount of mixed gas. The α-olefin used in the first stage and the second stage may be the same or different,
They may be used alone or in combination of two or more.

It is generally known that the above multistage polymerization is carried out in the presence of a titanium compound and an aluminum compound. As the titanium compound, for example, titanium trichloride and magnesium chloride are co-ground, and n-butyl o-titanate, 2-ethyl-hexanol, ethyl p-toluate, silicon tetrachloride, diisobutyl phthalate and the like are used. A spherical solid having an average particle diameter of 15 μm and the like may be used.
Examples of the aluminum compound include triethylaluminum. In the above multi-stage polymerization, a silicon compound such as diphenyldimethoxysilane may be added as an electron donor, or ethyl iodide may be further added.

In the multistage polymerization, the main polymerization is performed after the preliminary polymerization is performed first, instead of completing the polymerization once, so that a plurality of types of polymers can be continuously synthesized. Therefore, it is possible to synthesize a copolymer blended at a molecular level, which is completely different from that of a normal polymer blend.

The copolymer blended at the molecular level is
It has a finely dispersed structure in which crystal parts and non-crystal parts are very finely dispersed. This finely dispersed structure is very suitable for increasing the amount of the inorganic filler. That is, as the inorganic filler is added, the cross-sectional area of the copolymer that plays the role of a binder connecting the inorganic filler to the inorganic filler becomes smaller. At this time, the copolymer having a large dispersion structure becomes non-uniform in a very thin portion of the copolymer, and breaks easily from a weak portion. On the other hand, copolymers having a finely dispersed structure blended at the molecular level do not become non-uniform even if a large amount of inorganic filler is blended, and can exhibit average strength, so A large amount of inorganic filler can be dispersed in the composition as compared with the polymer blend of the above.

A method for producing a polypropylene resin composition by the above-mentioned multi-stage polymerization is described in, for example, JP-A-4-224.
No. 809, Japanese Unexamined Patent Publication No. 4-96912,
-96907, JP-A-3-174410,
JP-A-2-170803, JP-A-2-17080
No. 2, JP-A-61-42553, JP-A-3-
Specific contents are disclosed in JP-A-205439, JP-A-3-97747 and the like. In the present invention, a polypropylene-based resin obtained by any of these methods can be suitably used. Further, for example, commercially available products such as PER (manufactured by Tokuyama Soda Co., Ltd.) and Cataloy (manufactured by Himont Co., Ltd.) can also be used.

In the present invention, the polypropylene resin preferably has a DSC heat of fusion of 10 to 40 J / g. If it is less than 10 J / g, it will be a material with poor heat resistance, and if it exceeds 40 J / g, it will be a material with poor flexibility. More preferably, it is 25 to 40 J / g.
The DSC heat of fusion can be measured, for example, by using DSC220C (manufactured by Seiko Instruments Inc.) or the like.

The inorganic filler used in the present invention is not particularly limited. Examples thereof include calcium carbonate, fly ash, dehydrated sludge, natural silica, synthetic silica, kaolin, clay, titanium oxide, barium sulfate, zinc oxide, and hydroxide. Aluminum, alumina, magnesium hydroxide, talc, mica, glass flake, hydrotalcite,
Magnesium silicate, calcined talc, wollastonite,
Examples include potassium titanate, moss heidi, magnesium sulfate, sepiolite, zonolite, aluminum borate, silica balloon, glass balloon, copper, iron, iron oxide, carbon black, sendust, alnico magnets, magnetic powders such as various ferrites, cement, and the like.

In addition, the above-mentioned inorganic filler includes a coupling agent such as a silane-based, titanate-based, aluminate-based, zircoaluminum-based, phosphoric acid-based, carboxylic acid-based, fatty acid-based, oil / fat, wax, or surfactant, and a surface active agent. Surface treatment may be performed with a treatment agent or the like.

The amount of the inorganic filler is 50 to 900 parts by weight based on 100 parts by weight of the polypropylene resin. If it is less than 50 parts by weight, the effect of improving physical properties such as rigidity and molding shrinkage is insufficient, and if it is more than 900 parts by weight, the tensile elongation characteristics are reduced, so that it is limited to the above range. Preferably, it is 50 to 700 parts by weight.

The method for preparing the polypropylene resin composition of the present invention is not particularly limited, and examples thereof include a single-screw extruder, a twin-screw extruder, a Banbury mixer, a kneading roll, a Brabender plastgrab, a kneader and the like. For example, a method of mixing and dispersing the inorganic filler in the polyethylene resin can be employed.

The polypropylene resin composition of the present invention may contain additives such as an antioxidant, a stabilizer, a pigment, an antifogging agent, an antistatic agent and a flame retardant according to the purpose. The antioxidant and the stabilizer are not particularly limited as long as they prevent oxidative deterioration of the polymer, and include, for example, commercially available phenolic antioxidants, phosphorus antioxidants, amine antioxidants, sulfur Antioxidants and the like. These may be used alone or in combination of two or more.

The method for mixing the above additives with the polypropylene resin composition of the present invention is not particularly limited. For example, a method known in the art such as an extruder, a Banbury mixer, a kneading roll, a Brabender plastograph, a kneader and the like can be used. A method of mechanical melting and mixing can be employed.

The polypropylene resin composition of the present invention comprises:
For example, inflation molding using one or more extruders, single extrusion by T-die molding or the like, co-extrusion, a film by a conventionally known processing means such as extrusion lamination, etc.
It can be formed into a sheet or the like. Since the polypropylene-based resin composition of the present invention has a composition suitable for crosslinking and stretching, it can be molded by combining the above processing means according to the purpose.

The polypropylene resin composition of the present invention may further contain a pigment, an ultraviolet absorber, a flame retardant,
A plasticizer, a lubricant, an antistatic agent, and a dispersant such as a silane compound may be added. In addition, amino modification, epoxy modification,
Modified silicone oils such as carboxyl-modified, carbinol-modified, methacryl-modified, mercapto-modified, phenol-modified, polyether-modified, methylstyryl-modified, alkyl-modified and higher fatty acid ester-modified, and silicone modifiers may be added. These may be used alone,
Two or more kinds may be used in combination.

The polypropylene resin composition of the present invention comprises:
Since it is made of polypropylene resin with a wide crystallinity distribution,
Rich in flexibility, good dispersibility of various inorganic fillers, and exhibits good tensile elongation characteristics.

[0030]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Examples 1 to 7 and Comparative Examples 1 to 3 The DSC heat of fusion and melting point of the polypropylene resin shown in Table 1 and the amount of elution at each temperature were evaluated by the following methods. Squeezed.

Evaluation method (1) DSC heat of fusion, melting point Using DSC220C (manufactured by Seiko Denshi), about 10
mg was weighed and the temperature was increased at a rate of 5 ° C./min.
/ G unit. The peak top at the time of melting was defined as the melting point.

(2) Elution amount Temperature rise elution fractionation (TREF = Temperature)
Rising Elution Fractiona
portion) and high temperature GPC (SEC = Size E)
The measurement was carried out using a cross-separation chromatograph (CFC-150A, manufactured by Mitsubishi Yuka Co., Ltd.) equipped with an xfusion chromatograph portion as a system.

[0034]

[Table 1]

The polypropylene resin shown in Table 1 was replaced with Table 2
Was added in the composition shown in Table 3, kneaded and extruded with a PCM30 extruder (manufactured by Ikegai Co., Ltd.), and taken up with a sheet take-off machine (manufactured by Toyo Seiki Seisaku-sho, Ltd.) to produce a sheet. About the obtained sheet, using Tensilon (manufactured by A & D), the pulling speed was 200 m.
m / min, the dumbbell size was punched out by JIS No. 4 type, and a tensile test was performed. The results are shown in Table 3.

[0036]

[Table 2]

[0037]

[Table 3]

[0038]

As described above, the polypropylene resin composition of the present invention has the above-mentioned constitution, so that a large amount of inorganic filler can be blended without lowering the tensile elongation characteristics.
Excellent rigidity, low molding shrinkage, excellent dimensional stability and molding workability. Further, since a large amount of an inexpensive inorganic filler can be compounded, the cost is excellent. Therefore, the polypropylene-based resin composition of the present invention has stable stretchability, is excellent in sound insulation, heat resistance, flame retardancy, etc., as a material for a sheet, a film, and the like, and is also suitable as an injection molding material. is there.

Claims (2)

[Claims] 1. A polypropylene-based resin composition comprising a polypropylene-based resin and an inorganic filler, wherein the polypropylene-based resin has an elution amount at 0 ° C. or less in a cross-separation chromatograph of 10 to 10% of the total elution amount. 60% by weight, the elution amount exceeding 0 ° C. and less than 90 ° C. is 10 to 85% by weight of the total elution amount, and the elution amount at 90 ° C. or more is 5 to 50% of the total elution amount. % By weight, and the inorganic filler is the polypropylene resin 10
A polypropylene-based resin composition, which is blended in an amount of 50 to 900 parts by weight with respect to 0 parts by weight. 2. The multi-stage polymerization according to claim 1, wherein the polypropylene-based resin is a copolymer comprising propylene and at least one α-olefin different from propylene, and is polymerized by multi-stage polymerization. The polypropylene resin composition according to claim 1, which is obtained by polymerizing propylene or by copolymerizing propylene and an α-olefin.