JP2013231099A - Propylene polymer, propylene polymer composition, preliminary foamed particle foamed molding, injection-foamed molding, and method for producing them - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a preliminary foamed particle foamed molding comprising a propylene polymer composition, moldable by lower temperature steam, excellent in a fusion rate, and further excellent in secondary foamability and shock resistance; and to provide an injection-foamed molding having excellent moldability and uniform foaming cells, excellent in a surface appearance, and capable of reducing the weight at a high expansion ratio.SOLUTION: A propylene copolymer (A) includes 50-95 mol% of a constitutional unit [i] derived from propylene, 4.9-49.9 mol% of constitutional unit [ii] derived from 2-10C α-olefins excluding propylene, and 0.1-10 mol% of a constitutional unit [iii] derived from non-conjugated polyenes (wherein, the total of the constitutional units [i], [ii] and [iii] is defined as 100 mol%), and satisfies specific requirements (a) and (c).

Description

  The present invention relates to a propylene-based polymer, a propylene-based polymer composition, a copolymer or a pre-foamed particle foam molded body, an injection foam molded body, and a method for producing them.

  Polypropylene foam moldings are widely used as packaging materials, construction materials, heat insulation materials, etc. because they can utilize the excellent mechanical strength, heat resistance, and processability of polypropylene, and can add buffering properties and heat insulation properties.

  Recently, however, there are more opportunities for higher functionality than ever before. For example, for automotive applications, focusing on the superior properties of polypropylene-based pre-expanded particles (hereinafter referred to as “EPP molded products”), bumper core materials, door pads, pillars, tool boxes, floor mats, etc. Although it has been widely used, there has been a demand for weight reduction of vehicles due to recent environmental and energy problems, and at the same time, weight reduction of parts constituting the vehicle has been strongly demanded. Even if it is an EPP molded object, it is not an exception, and the lighter weight EPP molded object has been calculated | required, maintaining conventional rigidity, shock absorbing property, and impact energy absorption. Further, for example, a polystyrene pre-expanded particle foam molded body (hereinafter referred to as “EPS molded body”) is often used as a shipping box such as a fish box because of its high rigidity and low cost. It was. However, since the EPS molded body is inferior in impact resistance and heat resistance compared to the EPP molded body, it is difficult to repeatedly use it. In recent years, there have been many requests to use an EPP molded product that can be used repeatedly and with excellent environmental compatibility due to the growing awareness of environmental issues in public opinion. It has been desired.

  By the way, in order to obtain a highly rigid EPP molded product, some improvements have been made so far, for example, using a highly rigid polypropylene resin as a raw material. As a high-rigidity polypropylene resin, a propylene copolymer or a propylene homopolymer having a low comonomer composition ratio such as ethylene or butene as a copolymer component is generally known. By using these raw materials, It was possible to obtain a highly rigid EPP molded body. However, generally, a high-rigidity polypropylene-based resin has a melting point that rises at the same time as rigidity. When these high-rigidity raw materials are used, an increase in processing temperature for obtaining an EPP molded body, It was a rise. Conventionally, a molding machine for producing an EPP molded body has a structure corresponding to a high molding temperature, that is, a structure that can withstand high-pressure steam. When a rigid non-crosslinked polypropylene resin expanded particle (hereinafter, sometimes referred to as “EPP particle” or simply “pre-expanded particle”) is used to obtain a highly rigid EPP molded product, an EPP molded product is manufactured. For this reason, there are many cases where steam having a pressure higher than the pressure resistance of the molding machine is required, and further, it is difficult to obtain a sufficient fusion rate between the expanded particles. For these reasons, there has been a demand for a method of obtaining EPP particles that can be molded within the pressure resistance of existing molding machines.

  As a method for satisfying such a demand, for example, high-rigidity EPP molding using a polypropylene-based resin that has been used conventionally, in which the composition ratio of comonomer such as ethylene or butene copolymerized with polypropylene resin is a sufficient value. A method of obtaining a body has been proposed. In this method, the endothermic curve peak (hereinafter referred to as “high temperature”) is higher than the endothermic curve peak (hereinafter sometimes referred to as “inherent peak”) derived from the heat of fusion of the base resin in the DSC curve by differential scanning calorimetry of the expanded particles. This is a method in which the amount of heat of the high temperature peak is increased more than the value that has been conventionally managed. When the foamed particles obtained by this method are used, as in the case of trying to obtain a highly rigid EPP molded body using the highly rigid EPP particles obtained from the highly rigid polypropylene resin as described above, As a result, the molding temperature is greatly increased, and as a result, steam with a pressure exceeding the pressure resistance of the molding machine for producing the EPP molded body is often required, and the fusion rate between the expanded particles is sufficient. This causes a problem that it is difficult to obtain a correct value. Therefore, there has been a strong demand for a method for obtaining EPP particles that can be molded with lower temperature steam.

  In recent years, there has been a strong demand for weight reduction in automobile parts and the like in order to improve fuel consumption and reduce global warming gas, and the use of foam molded articles is increasing especially in interior parts. One of the foamed molded articles of polypropylene that is lightweight and excellent in rigidity is an injection foamed molded article.

  So far, in the injection molding of polypropylene resin, so-called injection foam molding has been performed in which foaming is performed for weight reduction, cost reduction, and prevention of warping and sink marks of the molded body. As a technology for highly foaming polypropylene-based resin, a resin containing a foaming agent is injection-molded in a mold space that is held so that the mold can be opened, and then the mold is opened to expand the space. There is a so-called core back method (moving cavity method) for foaming.

  Ordinary linear polypropylene resins are crystalline and have low melt tension (melting tension), and bubbles are easily destroyed. As a result, appearance defects called swirl marks are likely to occur on the surface of the molded body, and voids are likely to occur inside, making it difficult to increase the expansion ratio. In addition, since the bubbles were non-uniform and large, the resulting molded article was not sufficiently rigid. Note that the void means a coarse bubble generated when internal bubbles communicate with each other, and means a bubble whose diameter substantially exceeds 1.5 mm.

  As a method for improving foamability, a method has been proposed in which a crosslinking agent or a silane-grafted thermoplastic resin is added to increase the melt tension of a polypropylene resin. However, in this method, although a foamed molded article having a high expansion ratio can be obtained, the viscosity at the time of melting is excessively increased, and the surface properties of the obtained molded article are also poor.

  On the other hand, when used as an automobile part, it is often required to have high rigidity and high impact resistance. As a method for improving the impact resistance, a method has been proposed in which an amorphous rubber-like substance is added to a polypropylene resin by blending or multistage polymerization. However, with this method, although impact resistance is high, the dispersibility of the rubber component to be added is poor and the molding becomes poor, or the foamability of the resin is not sufficient, and a foamed molded product with a high foaming ratio of 2 times or more is required. Couldn't get.

  As described above, it has been difficult to obtain an injection foam molded article that has good injection foam moldability, excellent foam uniformity and surface appearance, and can be significantly reduced in weight at a high expansion ratio.

JP 2002-167460 A JP 2009-161668 A JP 2009-298145 A JP 2002-173564 A JP 2011-195705 A

  In the present invention, the foamed particles can be fused with low-temperature steam, and uniform foamed cells can be obtained with high foaming. Therefore, pre-foamed foamed molded articles that are highly rigid and lightweight, and have good moldability. An object of the present invention is to obtain an injection-foamed molded article having uniform foam cells, excellent surface appearance, and capable of being reduced in weight at a high foaming ratio.

  Another object of the present invention is to provide a propylene-based polymer and a propylene-based polymer composition that are suitable for a pre-expanded particle foam molded body and an injection foam molded body.

As a result of intensive studies, the present inventors have completed the present invention.
That is, the propylene-based copolymer (A) of the present invention comprises a structural unit derived from propylene [i] 50 to 95 mol% and a structural unit derived from an α-olefin having 2 to 10 carbon atoms excluding propylene [ii]. 4.9 to 49.9 mol% and structural unit [iii] 0.1 to 10 mol% derived from non-conjugated polyene (provided that the total of structural units [i], [ii] and [iii] 100 mol%) and the following requirements (a) and (c) are satisfied, preferably the following requirements (a) to (d) are satisfied.

(A) The intrinsic viscosity [η] measured at 135 ° C. in decalin is 0.1 to 5.0 (dL / g),
(B) The ratio (Mz / Mw) of z-average molecular weight (Mz) and weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) is 3.0 to 20.0,
(C) MFR ₁₀ obtained at 230 ° C. and 10 kg load according to JIS K-6721, and MFR _2.16 obtained at 230 ° C. and 2.16 kg load according to JIS K-6721 Ratio (MFR ₁₀ / MFR _2.16 ) is 8.0 to 150.0,
(D) Complex viscosity η * ₍ ω _{= 0.1)} of frequency (ω = _0.1 rad / s) obtained by linear viscoelasticity measurement (190 ° C.) using a rheometer, and frequency (ω = 100 rad / s) ) To the complex viscosity η * ₍ ω _{= 100)} (η * ₍ ω _{= 0.1)} / η * ₍ ω _{= 100)} ) is 5 to ₁₀₀ .

  The propylene copolymer composition (X) of the present invention comprises 5 to 95 parts by weight of the propylene copolymer (A) and a thermoplastic resin (B), preferably a crystalline olefin resin (BB) of 5 to 95. Parts by weight (however, the sum of (A) and (B) is 100 parts by weight).

  The propylene-based copolymer composition (X1) of the present invention satisfies the following requirements (a) to (d) and is composed of 50 to 95 mol% of structural units derived from propylene, ethylene, 1-butene and 4-methyl. A structural unit derived from 4.9 to 49.9 mol% derived from at least one α-olefin selected from pentene-1,1-hexene and 1-octene, and a structural unit derived from 5-vinyl-2-norbornene is 0. 1 to 10 mol% (provided that the total of the structural units [i], [ii] and [iii] is 100 mol%) 5 to 80 parts by weight of a propylene-based copolymer (A1) and polypropylene (B1 ) 95 to 20 parts by weight (provided that the total of (A1) and (B1) is 100 parts by weight) and satisfies the following requirement (xa).

(A) The intrinsic viscosity [η] measured at 135 ° C. in decalin is 0.1 to 5.0 (dL / g),
(B) The ratio (Mz / Mw) of z-average molecular weight (Mz) and weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) is 3.0 to 20.0,
(C) MFR ₁₀ obtained at 230 ° C. and 10 kg load according to JIS K-6721, and MFR _2.16 obtained at 230 ° C. and 2.16 kg load according to JIS K-6721 Ratio (MFR ₁₀ / MFR _2.16 ) is 8.0 to 150.0,
(D) Complex viscosity η * ₍ ω _{= 0.1)} of frequency (ω = _0.1 rad / s) obtained by linear viscoelasticity measurement (190 ° C.) using a rheometer, and frequency (ω = 100 rad / s) ) With the complex viscosity η * ₍ ω _{= 100)} (η * ₍ ω _{= 0.1)} / η * ₍ ω _{= 100)} ) is 5 to ₁₀₀ ,
(Xa) propylene copolymer composition and (X1) the melt tension MT _(X1) at 230 ° C., the ratio of polypropylene melt tension MT at 230 ° C. of _{(B1) (B1) (MT} (X1) / MT ( _B1) ) is 2.0 to 10.0.

The molded body of the present invention is obtained using the propylene copolymer (A), the propylene copolymer composition (X), or the propylene copolymer composition (X1).
The pre-expanded particle foam molded article of the present invention is a pre-form obtained by using the propylene copolymer (A), the propylene copolymer composition (X) or the propylene copolymer composition (X1). The foamed particles are obtained by filling a mold and heating and foaming.

  The injection-foamed molded article of the present invention is produced by an injection molding method using the propylene-based copolymer (A), the propylene-based copolymer composition (X), or the propylene-based copolymer composition (X1). can get.

  The method for producing a pre-expanded particle foam molded article of the present invention uses the propylene-based copolymer (A), the propylene-based copolymer composition (X), or the propylene-based copolymer composition (X1). A step of filling the obtained pre-expanded particles into a mold and foaming by heating is included.

  The method for producing an injection-foamed molded article according to the present invention uses the propylene-based copolymer (A), the propylene-based copolymer composition (X), or the propylene-based copolymer composition (X1). Forming step.

  According to the present invention, pre-expanded particle foam molding that can be molded from a specific propylene polymer or propylene polymer composition with low-temperature steam, has excellent fusion rate, and also has excellent impact resistance. It is possible to obtain an injection foam molded article having good body and moldability, uniform foamed cells, excellent surface appearance, and capable of reducing the weight at a high foaming ratio.

<Propylene copolymer>
The propylene-based copolymer (A) according to the present invention satisfies the following requirements (a) and (c), preferably satisfies (a) to (d), and is a structural unit [i] 50 to 95 derived from propylene. Constituent units selected from mol%, α-olefins having 2 to 10 carbon atoms excluding propylene [ii] 4.9 to 49.9 mol%, and constituent units derived from non-conjugated polyenes [iii] 0.1 10 mol% (provided that the total of the structural units [i], [ii] and [iii] is 100 mol%). It is preferable that the structural units [i], [ii], and [iii] are in the above ranges because a copolymer (A) that is more excellent in moldability can be obtained.

In the present invention, “α-olefin having 2 to 10 carbon atoms” does not include propylene unless otherwise specified.
Moreover, when using a copolymer (A) for the copolymer composition (X or X1) mentioned later, as a propylene-type copolymer (A or A1) based on this invention, Preferably, the said structural unit [ i] is 55 to 95 mol%, the structural unit [ii] is 4.9 to 44.9 mol%, and the structural unit [iii] is 0.1 to 7.0 mol%. However, it is preferable from the viewpoint of compatibility with thermoplastic resins, particularly polypropylene, and the fact that no gel component is produced during production (provided that the total of structural units [i], [ii] and [iii] is 100 mol%).

It should be noted that other copolymerization components may be included within the range not impairing the object of the present invention, and these are also within the scope of the present invention.
(Α-olefin)
The α-olefin having 2 to 10 carbon atoms excluding propylene may be linear, branched or cyclic. For example, ethylene, 1-butene, 2-butene, 1-pentene, 3-methyl-1 Linear or branched α-olefins such as -butene, 1-hexene, 4-methyl-1-pentene, 3-methyl-1-pentene, 1-octene, 1-nonene, 1-decene; cyclopentene, cyclohexene And cyclic olefins such as cycloheptene. These α-olefins may be used alone or in combination of two or more.

Among these, ethylene, 1-butene, 4-methyl-1-pentene, 1-hexene and 1-octene are preferable.
(Non-conjugated polyene)
Specific examples of the non-conjugated polyene include dicyclopentadiene, 1,4-hexadiene, cyclooctadiene, methylene norbornene, ethylidene norbornene, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene. 4-ethyl-1,4-hexadiene, 5-methyl-1,4-heptadiene, 5-ethyl-1,4-heptadiene, 5-methyl-1,5-heptadiene, 6-methyl-1,5-heptadiene 5-ethyl-1,5-heptadiene, 4-methyl-1,4-octadiene, 5-methyl-1,4-octadiene, 4-ethyl-1,4-octadiene, 5-ethyl-1,4-octadiene 5-methyl-1,5-octadiene, 6-methyl-1,5-octadiene, 5-ethyl-1,5-octadiene, 6-ethyl-1,5-octadiene, 6-methyl-1,6-octadiene 7-methyl-1,6-octadiene, 6-ethyl -1,6-octadiene, 4-methyl-1,4-nonadiene, 5-methyl-1,4-nonadiene, 4-ethyl-1,4-nonadiene, 5-ethyl-1,4-nonadiene, 5-methyl -1,5-nonadiene, 6-methyl-1,5-nonadiene, 5-ethyl-1,5-nonadiene, 6-ethyl-1,5-nonadiene, 6-methyl-1,6-nonadiene, 7-methyl -1,6-nonadiene, 6-ethyl-1,6-nonadiene, 7-ethyl-1,6-nonadiene, 7-methyl-1,7-nonadiene, 8-methyl-1,7-nonadiene, 7-ethyl -1,7-nonadiene, 5-methyl-1,4-decadiene, 5-ethyl-1,4-decadiene, 5-methyl-1,5-decadiene, 6-methyl-1,5-decadiene, 5-ethyl -1,5-decadiene, 6-ethyl-1,5-decadiene, 6-methyl-1,6-decadiene, 7-methyl-1,6-decadiene, 6-ethyl-1,6-decadiene, 7-ethi 1,6-decadiene, 7-methyl-1,7-decadiene, 8-methyl-1,7-decadiene, 7-ethyl-1,7-decadiene, 8-ethyl-1,7-decadiene, 8- Non-conjugated dienes such as methyl-1,8-decadiene, 9-methyl-1,8-decadiene, 8-ethyl-1,8-decadiene, 9-methyl-1,8-undecadiene;
6,10-dimethyl-1,5,9-undecatriene, 4,8-dimethyl-1,4,8-decatriene (DMDT), 5,9-dimethyl-1,4,8-decatriene, 6,9 -Dimethyl-1,5,8-decatriene, 6,8,9-trimethyl-1,5,8-decatriene, 6-ethyl-10-methyl-1,5,9-undecatriene, 4-ethylidene-1 , 6-octadiene, 7-methyl-4-ethylidene-1,6-octadiene, 4-ethylidene-8-methyl-1,7-nonadiene (EMND), 7-methyl-4-ethylidene-1,6-nonadiene, 7-ethyl-4-ethylidene-1,6-nonadiene, 6,7-dimethyl-4-ethylidene-1,6-octadiene, 6,7-dimethyl-4-ethylidene-1,6-nonadiene, 4-ethylidene- 1,6-decadiene, 7-methyl-4-ethylidene-1,6-decadiene, 7-methyl-6-propyl-4-ethylidene-1,6-octadiene, 4- Non-conjugated trienes such as ethylidene-1,7-nonadiene, 8-methyl-4-ethylidene-1,7-nonadiene, 4-ethylidene-1,7-undecadiene and the like can be mentioned. These non-conjugated polyenes can be used alone or in combination of two or more.

  Among these, 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene, dicyclopentadiene, 4,8-dimethyl-1,4,8-decatriene (DMDT), 4-ethylidene-8-methyl- 1,7-nonadiene (EMND) is preferred, and 5-vinyl-2-norbornene (VNB) is more preferred.

(Conjugated polyene)
In the present invention, for example, a conjugated polyene may be included as another polymerization component as long as the object of the present invention is not impaired.

  Examples of the conjugated polyene include 1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, 1,3-heptadiene, 1,3-octadiene, 1-phenyl-1,3-butadiene, and 1-phenyl. -2,4-pentadiene, isoprene, 2-ethyl-1,3-butadiene, 2-propyl-1,3-butadiene, 2-butyl-1,3-butadiene, 2-pentyl-1,3-butadiene, 2 Conjugated dienes such as -hexyl-1,3-butadiene, 2-heptyl-1,3-butadiene, 2-octyl-1,3-butadiene, 2-phenyl-1,3-butadiene; 1,3,5-hexa Examples thereof include conjugated trienes such as triene.

Next, requirements (a) to (d) are shown.
Requirement (a): [Intrinsic viscosity [η]]
In the propylene-based copolymer according to the present invention, the intrinsic viscosity [η] in decalin at 135 ° C. is usually in the range of 0.1 to 5.0 (dL / g). When the intrinsic viscosity is within this range, the balance between resin fluidity and melt tension is excellent.

Requirement (b): [Molecular weight distribution [Mz / Mw]]
The propylene copolymer according to the present invention generally has a ratio (Mz / Mw) of z-average molecular weight (Mz) and weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) to 3. It is in the range of 0 to 20.0. When the value of Mz / Mw is large, the amount of long chain branching is large and the melt tension becomes high.

Requirements (c): [ratio (MFR ₁₀ / MFR _2.16)]
The propylene-based copolymer according to the present invention includes MFR ₁₀ obtained at 230 ° C. and 10 kg load according to JIS K-6721, and 230 ° C. and 2.16 kg load according to JIS K-6721. The ratio (MFR ₁₀ / MFR _2.16 ) with MFR _2.16 obtained in the above is usually in the range of 8.0 to 150.0. When the ratio (MFR ₁₀ / MFR _2.16 ) is within the above range, the fluidity of the resin under two loads tends to change, and the rate of change in viscosity with respect to the shear rate is small. Therefore, when it exists in this range, the viscosity change of resin is small in the specific shear rate range, and it is excellent in workability.

Requirement (d): [ratio (η * ₍ ω _{= 0.1)} / η * ₍ ω _{= 100)} )]
Complex viscosity η * ₍ ω _{= 0.1)} of frequency (ω = _0.1 rad / s) and complex of frequency (ω = 100 rad / s) obtained by linear viscoelasticity measurement (190 ° C.) using a rheometer. The ratio (η * ₍ ω _{= 0.1)} / η * ₍ ω _{= 100)} ) to the viscosity η * ₍ ω _{= 100)} is usually 5 to ₁₀₀ . When the ratio (η * ₍ ω _{= 0.1)} / η * ₍ ω _{= 100)} ) is in the above range, it means that it has a long-chain branched structure and is excellent in melt tension.

[Propylene-based copolymer production method]
Next, the manufacturing method of the propylene-type copolymer which concerns on this invention is demonstrated. The production method of the copolymer of the present invention is not particularly limited.

<Propylene-based copolymer composition>
The propylene copolymer composition (X) of the present invention comprises 5 to 95 parts by weight of the propylene copolymer according to the present invention, a thermoplastic resin (B) described later, preferably a crystalline olefin resin (BB). 95 to 5 parts by weight (provided that the total of (A) and (B) is 100 parts by weight). Within this range, a composition having excellent material strength and a good balance between moldability and melt tension can be obtained.

  Further, the propylene copolymer composition (X1) of the present invention is 5 to 80 parts by weight of the propylene copolymer (A1) of the present invention, and 95 to polypropylene (B1) as the thermoplastic resin (B). 20 parts by weight (provided that the total of (A) and (B) is 100 parts by weight) and satisfies the following requirement (xa). Such a copolymer composition (X1) is preferable because it is excellent not only in material strength but also in balance between moldability and melt tension.

Requirement (xa): [ratio (MT _(X1) / MT _(B1) )]
Copolymer composition of the present invention the melt tension MT _(X1) at 230 ° C. of (X or X1), the ratio of polypropylene melt tension MT at 230 ° C. of _{(B1) (B1) (MT} (X1) / MT ( _B1) ) is usually from 2.0 to 10.0. The ratio (MT _(X1) / MT _(B1) ) being in the above range means that the melt characteristics in the copolymer composition are improved compared to polypropylene (B1), and the moldability is improved. Excellent.

[Thermoplastic resin (B)]
Examples of the thermoplastic resin (B) include known resins and are not particularly limited, but a crystalline olefin resin (BB) is preferable, and polypropylene (B1) is more preferable.

Examples of the thermoplastic resin include polyolefin, polyamide, polyester, polyurethane, polystyrene, polyimide, and polyether.
Unlike the copolymer according to the present invention, the crystalline olefin resin (BB) is a resin having a melting point measured by DSC of 70 ° C. or higher, preferably 110 to 250 ° C.

  Examples of the crystalline olefin resin (BB) include low density, medium density, high density polyethylene, high pressure method low density polyethylene, isotactic polypropylene, syndiotactic polypropylene, poly 1-butene, poly 4-methyl-1- Pentene, poly-3-methyl-1-butene, ethylene / α-olefin random copolymer, propylene / α-olefin random copolymer, 1-butene / α-olefin random copolymer, cyclic olefin copolymer, chlorine Polyolefin, vinyl acetate copolymer, ethylene / methacrylic acid acrylate copolymer, ionomer, ethylene / vinyl alcohol copolymer, and the like.

  Polypropylene (B1) is a propylene homopolymer or propylene such as propylene / ethylene block copolymer, propylene / ethylene random copolymer and propylene / ethylene / 1-butene random copolymer; Random copolymer or block copolymer of α-olefin (excluding propylene), and usually a constitutional unit derived from propylene and an α-olefin having 2 to 20 carbon atoms (excluding propylene) In a total of 100 mol% of the units, a structural unit derived from propylene is contained in an amount of 50 mol% or more. The stereoregularity may be either an isotactic structure or a syndiotactic structure.

  Polypropylene (B1) usually has a melting point obtained by differential scanning calorimetry (DSC) in the range of 110 to 170 ° C. It is preferable for the melting point of polypropylene (B1) to be in the above-mentioned range since the balance between heat resistance and mechanical properties is excellent.

Melt tension MT at 230 ° C. of polypropylene _(B1) (B1) is usually 1 to 200 (mN).
These thermoplastic resins can be used singly or in combination of two or more. Moreover, the manufacturing method of these thermoplastic resins is not specifically limited, It can manufacture with various catalysts and various well-known manufacturing methods.

[Other ingredients (additives)]
The propylene-based copolymer and the propylene-based copolymer composition (hereinafter sometimes referred to as the copolymer or the composition) according to the present invention are stable in weather resistance as long as the object of the present invention is not impaired. Agent, heat stabilizer, antistatic agent, anti-slip agent, anti-blocking agent, anti-fogging agent, lubricant, pigment, dye, plasticizer, anti-aging agent (stabilizer), hydrochloric acid absorbent, antioxidant, secondary anti-oxidant Additives such as an oxidizing agent may be blended as necessary. The blending amount is not particularly limited, but is usually about 0.001 to 10 parts by weight with respect to 100 parts by weight of the copolymer or the composition.

  Further, if necessary, a foaming agent, a foaming aid, a dispersant, a dispersion aid, a dispersion strengthening agent, a nucleating agent, a vulcanizing agent, a vulcanization accelerator, a vulcanizing aid, a reinforcing agent, a filler, a softening agent, Other additives such as processing aids, activators, hygroscopic agents, crosslinking agents, co-crosslinking agents, crosslinking aids, adhesives, flame retardants, mold release agents, pigments, dyes, and the like can be blended.

These additives may be used alone or in combination of two or more.
These additives are added to the base resin melted in the extruder and kneaded, for example, when the resin particles are produced by cutting the strands extruded by the extruder, and contained in the resin particles. be able to.

[Graft modified product]
In the present invention, at least part or all of the propylene copolymer and the thermoplastic resin may be graft-modified with a polar monomer.

  For example, a part or all of the copolymer (A) may be graft-modified, or a part or all of the resin (B) may be graft-modified, and the copolymer (A) or resin (B ) May be partially or entirely graft-modified.

  Examples of such polar monomers include hydroxyl group-containing ethylenically unsaturated compounds, amino group-containing ethylenically unsaturated compounds, epoxy group-containing ethylenically unsaturated compounds, aromatic vinyl compounds, unsaturated carboxylic acids or their derivatives, and vinyl ester compounds. , Vinyl chloride, carbodiimide compounds and the like. In particular, an unsaturated carboxylic acid or a derivative thereof is preferable. Examples of the unsaturated carboxylic acid or a derivative thereof include an unsaturated compound having one or more carboxylic acid groups, an ester of a compound having a carboxylic acid group and an alkyl alcohol, and an unsaturated compound having one or more carboxylic anhydride groups. Examples of the unsaturated group include a vinyl group, a vinylene group, and an unsaturated cyclic hydrocarbon group.

  Specifically, for example, acrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, nadic acid [trademark] (endocis-bicyclo [2.2.1] hept- Examples of unsaturated carboxylic acids such as 5-ene-2,3-dicarboxylic acid) or derivatives thereof include acid halides, amides, imides, anhydrides, esters, and the like. Specific examples of such derivatives include, for example, maleyl chloride, maleimide, maleic anhydride, citraconic anhydride, monomethyl maleate, dimethyl maleate, glycidyl maleate and the like.

These unsaturated carboxylic acids and / or derivatives thereof can be used singly or in combination of two or more.
The modification is obtained by graft polymerizing a polar monomer to the object to be modified. When grafting such a polar monomer as described above to the object to be modified, the polar monomer is usually used in an amount of 1 to 100 parts by weight with respect to 100 parts by weight of the object to be modified. This graft polymerization is usually performed in the presence of a radical initiator.

As the radical initiator, an organic peroxide or an azo compound can be used.
The radical initiator can be used as it is mixed with the modified substance and the polar monomer, but can also be used after being dissolved in a small amount of an organic solvent. As the organic solvent, any organic solvent that can dissolve the radical initiator can be used without particular limitation.

Further, when the polar monomer is graft-polymerized on the object to be modified, a reducing substance may be used. When a reducing substance is used, the graft amount of the polar monomer can be improved.
Graft modification of a modified body with a polar monomer can be performed by a conventionally known method. For example, the modified body is dissolved in an organic solvent, and then a polar monomer and a radical initiator are added to the solution. The reaction can be carried out by reacting at a temperature of preferably 80 to 190 ° C. for usually 0.5 to 15 hours, preferably 1 to 10 hours.

  In addition, a polymer composition containing a modified body can be produced by reacting the body to be modified with a polar monomer using an extruder or the like. This reaction is usually performed at a temperature equal to or higher than the melting point of the object to be modified. It is desirable to be performed for 10 minutes. When the copolymer (A) is modified, for example, it is usually performed at a temperature of 160 to 300 ° C., preferably 180 to 250 ° C., usually for 0.5 to 10 minutes.

The modification amount (the graft amount of the polar monomer) of the modified product thus obtained is usually 0.1 to 50% by weight when the modified product is 100% by weight.
In the present invention, a copolymer composition can be obtained by kneading one or more of these modified products and an unmodified product selected from the copolymer (A) and the resin (B).

  Moreover, although content of a polar monomer is not specifically limited, 0.001 to 50 weight% is preferable with respect to 100 weight% of copolymer compositions. The content of the polar monomer can be easily designed according to the purpose, for example, by appropriately selecting the grafting conditions.

When the modified body is used, compatibility or adhesion with other materials can be added, and the wettability of the surface of the obtained molded body may be improved.
Moreover, in this invention, another polymer, for example, an elastomer etc., can be suitably mix | blended in the range which does not impair the characteristic which this modified body has. Their blending may be in the graft modification step or after modification.

  Examples of the elastomer include ethylene-propylene rubber, ethylene-1-butene rubber, propylene-1-butene rubber, styrene-butadiene rubber and hydrogenated products thereof, isoprene rubber, neoprene rubber, nitrile rubber, and styrene-butadiene block copolymer elastomer. And elastomers such as hydrogenated products thereof.

  In the present invention, known process stabilizers, heat stabilizers, heat aging agents, fillers, pressure-sensitive adhesives, and the like can be appropriately added as long as the properties of the modified product are not impaired. Examples of these additives include the other components described above.

[Propylene-based copolymer composition production method]
The propylene-based copolymer composition of the present invention can be produced by employing any known method. For example, the propylene-based copolymer, a thermoplastic resin, and other components and modifications added as desired. The body is mixed with various known methods such as a Henschel mixer, a V-blender, a ribbon blender, a tumbler blender, etc. After kneading, it can be produced by adopting a method of granulating or pulverizing.

In addition, the same method can be employ | adopted suitably for the propylene-type copolymer of this invention.
<Molded body>
The propylene-based copolymer or propylene-based copolymer composition of the present invention can be widely used for conventionally known polyolefin applications, and can be suitably used for pre-expanded particle foam molded products and injection foam molded products. In addition, the copolymer or the composition of the present invention can be used as a part of a molded product to be used as a multilayer laminate. The multilayer laminate is a laminate in which at least one layer thereof is a layer comprising the copolymer or the composition, and is a component of the multilayer film and sheet, multilayer container, multilayer tube, water-based paint Multilayer coating film laminated body etc. which are contained as are mentioned.

<Pre-foamed particle foam molding>
The pre-expanded particle foam molded article of the present invention comprises a propylene polymer or a propylene polymer composition.

According to the present invention, it is possible to obtain a pre-expanded particle foam molded body that can be molded with lower temperature steam, has an excellent fusion rate, and also has an excellent impact resistance.
(Resin particles)
The propylene-based copolymer or propylene-based copolymer composition of the present invention is a resin particle having a weight of preferably 0.1 to 20 mg, using the above-described method for producing a propylene-based copolymer composition. Processed. Generally, it is preferable to melt by using an extruder and to manufacture by a strand cut method. For example, a resin extruded in a strand form from a circular die is cooled and solidified with water, air, or the like to obtain resin particles having a desired shape.

  The melting point of the resin particles is preferably 130 ° C. or higher in order to enhance the mechanical properties such as the compression strength of the final molded body. The upper limit of the melting point is usually about 170 ° C. Further, the resin particles preferably have an MFR of 0.3 to 100 g / 10 min in consideration of the heat resistance of the foamed molded product and the foaming efficiency at the time of producing the foamed particles.

(Cell nucleating agent)
Moreover, when a cell nucleating agent is added during the production of the resin particles, the cell diameter when the resin pre-expanded particles are prepared can be adjusted to a desired value. As the cell nucleating agent, nucleating agents such as talc, calcium carbonate, silica, kaolin, titanium oxide, bentonite and barium sulfate are generally used. The amount of cell nucleating agent added varies depending on the type of components in the propylene-based copolymer or propylene-based copolymer composition used and the type of cell nucleating agent. Or it is preferable that it is about 0.001 weight part or more and 2 weight part or less with respect to 100 weight part of propylene-type copolymer compositions.

(Dispersion medium)
The dispersion medium is generally an aqueous medium, preferably water, and more preferably ion-exchanged water. However, the dispersion medium is not limited to water, and the solvent or liquid that does not dissolve the resin particles and can disperse the resin particles. Can be used. Examples of the dispersion medium other than water include ethylene glycol, glycerin, methanol, ethanol, and the like. The aqueous medium includes a mixed solution of water and an organic solvent such as the alcohol.

(Foaming agent)
Examples of blowing agents include aliphatic hydrocarbons such as propane, butane, hexane, and heptane, cyclic aliphatic hydrocarbons such as cyclobutane and cyclohexane, chlorofluoromethane, trifluoromethane, 1,2-difluoroethane, 1,2 , 2,2-tetrafluoroethane, organic physical foaming agents such as halogenated hydrocarbons such as methyl chloride, ethyl chloride and methylene chloride, and so-called inorganic physical foaming agents such as nitrogen, oxygen, air, carbon dioxide and water. Illustrated. An organic physical foaming agent and an inorganic physical foaming agent can be used in combination. In the present invention, those mainly composed of one or more inorganic physical foaming agents selected from the group of nitrogen, oxygen, air, carbon dioxide and water are particularly preferably used. Among these, carbon dioxide, nitrogen, and air are preferable in view of stability of the apparent density of the expanded particles, environmental load, cost, and the like.

(Foaming aid)
In the present invention, in addition to the foaming agent, a foaming aid may be added as necessary. The foaming aid exhibits actions such as lowering the decomposition temperature of the foaming agent, promoting decomposition, or uniforming the bubbles.

  Examples of the foaming aid include metal compounds such as zinc, calcium, lead, iron and barium, organic acids such as salicylic acid, phthalic acid, stearic acid, oxalic acid and citric acid or salts thereof, talc, barium sulfate and silica. Fine inorganic particles, urea or a derivative thereof. Also, polyvalent carboxylic acids such as citric acid, oxalic acid, fumaric acid, phthalic acid, malic acid, tartaric acid, lactic acid, cyclohexane 1,2-dicarboxylic acid, camphoric acid, ethylenediaminetetraacetic acid, triethylenetetramine hexaacetic acid and nitrilolic acid And inorganic carbonate compounds such as sodium hydrogen carbonate, sodium aluminum hydrogen carbonate and potassium hydrogen carbonate, and intermediates produced by these reactions, for example, salts of polycarboxylic acids such as sodium dihydrogen citrate and potassium oxalate And so on. Examples of commercially available products include cell paste K5 (trade name; manufactured by Eiwa Kasei Kogyo Co., Ltd., urea) and FE-507 (trade name: manufactured by Eiwa Kasei Kogyo Co., Ltd., baking soda).

Although the compounding quantity of a foaming adjuvant is not specifically limited, It is 0.1-5 weight part normally with respect to 100 weight part of this copolymer or this composition.
The foaming agent or foaming aid may be dry blended before extrusion molding of the foamed molded article and decomposed during extrusion molding, or may be melt blended into pellets in advance.

(Dispersant)
In the present invention, it is preferable to add a dispersant to the dispersion medium so that the surface-modified particles under heating in the container do not fuse with each other in the container. Such a dispersant is not limited as long as it prevents fusion of the surface-modified particles in the container, and can be used regardless of whether it is organic or inorganic. Inorganic substances are preferred. For example, natural or synthetic clay minerals such as amusnite, kaolin, mica, clay, aluminum oxide, titanium oxide, basic magnesium carbonate, basic zinc carbonate, calcium carbonate, iron oxide and the like in one kind or a combination of several kinds Can be used.

  The amount of dispersant used varies depending on the type and amount of components in the propylene-based copolymer or propylene-based copolymer composition, foaming agent, etc., and cannot be specified in general, but the propylene-based copolymer or propylene-based copolymer The amount is preferably 0.2 parts by weight or more and 10 parts by weight or less, and more preferably 0.5 parts by weight or more and 5.0 parts by weight or less with respect to 100 parts by weight of the combined composition.

(Dispersing aid)
In the present invention, a dispersion aid may be used together with the dispersant. As the dispersion aid, an anionic surfactant having a linear carbon chain having 10 to 18 carbon atoms as a hydrophobic group is preferable. Examples of the anionic surfactant having a linear carbon chain having 10 to 18 carbon atoms as a hydrophobic group include an alkyl sulfate having 10 to 18 carbon atoms, an alkyl sulfonate having 10 to 18 carbon atoms, and 10 to 10 carbon atoms. 18 fatty acid salt C10-18 alkyl phosphate and the like. Among these, alkyl sulfonates having 10 to 18 carbon atoms are preferable from the viewpoints of dispersion stability, fusion properties of molded articles, prevention of mold contamination / corrosion and cost, and wastewater treatment. Use of an alkyl sulfonate is more preferable because the effect can be maximized. Examples of the linear alkyl sulfonate having 12 carbon atoms include sodium lauryl sulfonate.

  The amount of dispersing aid varies depending on the type, the type and amount of components used in the propylene copolymer or propylene copolymer composition, the type of foaming agent, etc., but cannot be specified unconditionally. It is preferable that it is 5-10 weight part. It is preferable for the amount of the dispersion aid to be in the above-mentioned range because better dispersion stability tends to be obtained.

(Dispersion strengthening agent)
Furthermore, in the present invention, together with the dispersant, a dispersion strengthening agent that prevents fusion of the surface-modified particles in the container may be used even if the amount of the dispersant added is reduced. Examples of the dispersion strengthening agent include inorganic sulfate, magnesium chloride, magnesium nitrate, aluminum chloride, aluminum nitrate, iron chloride, iron nitrate and the like. The amount of the dispersion strengthening agent varies depending on the type, the type and amount of the propylene copolymer or propylene copolymer composition used, the type of foaming agent, etc. It is preferably ˜30% by weight.

Examples of the inorganic sulfate include magnesium sulfate (MgSO ₄ ), potassium sulfate (K ₂ SO ₄ ), silver sulfate (Ag ₂ SO ₄ ), calcium sulfate (CaSO ₄ ), barium sulfate (BaSO ₄ ), lead sulfate (PbSO ₄ ). ), Strontium sulfate (SrSO ₄ ), aluminum sulfate, iron sulfate and the like, and these can be used alone or in combination. Among them, it is preferable to use an inorganic sulfate that is insoluble in water because good dispersion stability can be obtained even in a relatively small amount. Examples of inorganic sulfates that are insoluble in water include calcium sulfate (CaSO ₄ ), barium sulfate (BaSO ₄ ), lead sulfate (PbSO ₄ ), and strontium sulfate (SrSO ₄ ). Of these, barium sulfate is more preferred because of its good dispersibility. Here, the term “insoluble in water” means that the solubility in 100 ml of water at 100 ° C. is 1 g or less.

  The inorganic sulfate is preferably in the form of fine powder, more preferably an average particle size of 0.01 to 20 μm, and still more preferably 0.01 to 10 μm. The average particle size of the inorganic sulfate was obtained by calculating the particle size distribution using a laser light diffraction / scattering type particle size distribution analyzer, and calculating the cumulative curve with the total volume of the powder group from which the particle size distribution was determined as 100%. This refers to the particle diameter (Median diameter) at the point where the cumulative curve is 50%.

(Preparation of pre-expanded particles)
The pre-foamed particles include, for example, a foaming agent containing carbon dioxide and a dispersion liquid containing the resin particles, a dispersion medium, a dispersing agent, a dispersion aid and a dispersion strengthening agent used as necessary, in a pressure vessel. Charged into a pressure vessel, heated to a predetermined temperature above the softening temperature of the resin, and released the dispersion under an atmosphere of lower pressure than in the pressure vessel while keeping the temperature and pressure constant under pressure. It is obtained by doing.

  The pressure vessel to be used is not particularly limited as long as it can withstand the pressure in the vessel and the temperature in the vessel at the time of producing the pre-foamed particles, and examples thereof include an autoclave type pressure vessel.

  Examples of the blowing agent containing carbon dioxide include carbon dioxide or a mixed blowing agent containing carbon dioxide as a main component. The content of carbon dioxide in the mixed foaming agent is 50% by weight or more. Examples of blowing agents that can be used in combination with carbon dioxide include aliphatic hydrocarbons such as propane, butane, pentane, hexane and heptane, cyclic aliphatic hydrocarbons such as cyclobutane and cyclopentane, trichlorofluoromethane, dichlorodi Examples thereof include volatile organic compounds such as halogenated hydrocarbons such as fluoromethane, dichlorotetrafluoroethane, methyl chloride, ethyl chloride, and methylene chloride, inorganic gases such as nitrogen, and water.

  The amount of blowing agent containing carbon dioxide varies depending on the type of components used in the propylene-based copolymer or propylene-based copolymer composition, the type of blowing agent, the desired expansion ratio, etc. However, it is preferably 2 parts by weight or more and 60 parts by weight or less with respect to 100 parts by weight of the resin particles.

  The amount of water constituting the dispersion is 100 parts by weight or more and 500 parts by weight or less with respect to 100 parts by weight of the resin particles in order to improve the dispersibility of the resin particles in the dispersion medium. Is preferred.

  In this way, a foaming agent containing carbon dioxide is added to a dispersion liquid containing resin particles, water, a dispersant, a dispersion aid and a dispersion strengthener used as necessary. Under stirring, the pressure is increased to a predetermined pressure, the temperature is increased to a predetermined temperature, and the pressure is maintained for a certain time, usually 5 to 180 minutes, preferably 10 to 60 minutes. Thereafter, the pre-expanded particles can be produced by releasing the pressurized dispersion liquid in a low-pressure atmosphere (usually atmospheric pressure) by opening a valve provided at the lower part of the pressure-resistant container.

  When the dispersion containing the resin particles is discharged into a low-pressure atmosphere, it can be discharged through an opening orifice having a diameter of 2 to 10 mm for the purpose of adjusting the flow rate and reducing variation in magnification. In some cases, the low-pressure atmosphere is heated with steam for the purpose of increasing the expansion ratio.

  The temperature at which the pressure vessel contents are heated (hereinafter sometimes referred to as foaming temperature) varies depending on the melting point [Tm (° C.)] of the copolymer or copolymer composition used, the type of foaming agent, etc. Cannot be defined, but is generally determined from the range of Tm−30 (° C.) to Tm + 10 (° C.). The pressure in the pressure vessel (hereinafter sometimes referred to as foaming pressure) varies depending on the type of copolymer or copolymer composition used, the type of foaming agent, and the expansion ratio of desired pre-expanded particles. However, it is determined from the range of 1 to 8 MPa (gauge pressure).

(Preparation of pre-expanded particle foam molding)
The pre-expanded particles obtained as described above can be formed into a foam-molded product by a conventionally known molding method. For example, a) Pre-expanded particles are pressurized with an inorganic gas, such as air or nitrogen, impregnated with the inorganic gas in the pre-expanded particles to give a predetermined internal pressure of the pre-expanded particles, filled in a mold, B) a method in which the pre-expanded particles are compressed by gas pressure and filled in a mold, and a heat-fusing with steam using the recovery force of the pre-expanded particles, c) a pre-treatment. A method such as a method in which pre-expanded particles are filled in a mold without being heated and heat-sealed with water vapor can be used.

The in-mold foam-molded product obtained by using the foamed particles by the production method of the present invention can be used for applications such as a heat insulating material, a buffer packaging material, an automobile interior member, and a core material for an automobile bumper.
<Injection foam molding>
The injection foam molded article of the present invention comprises a propylene polymer or a propylene polymer composition.

According to the present invention, it is possible to obtain an injection foam molded article having good moldability, uniform foam cells, excellent surface appearance, and capable of being reduced in weight at a high foaming ratio.
The injection-foamed molded article of the present invention is produced by melt-kneading a propylene-based polymer or propylene-based copolymer composition and a foaming agent and performing foam molding, for example, injection foam molding.

The foaming agent is not particularly limited as long as the foamed molded article of the present invention can be produced. Typically, the foaming agent is classified into a physical foaming agent and a chemical foaming agent.
Examples of the physical foaming agent include a solvent-type foaming agent and a gaseous foaming agent.

The solvent-type foaming agent is generally a substance that functions as a foaming agent by being injected from a cylinder portion of an injection molding machine, absorbed or dissolved in a molten raw material resin, and then evaporated in an injection mold.
Examples of the solvent-type blowing agent include low-boiling point aliphatic hydrocarbons such as propane, butane, neopentane, heptane, isohexane, hexane, isoheptane, heptane, and low-boiling point fluorine-containing hydrocarbons typified by CFCs. It is done.

  Examples of the gaseous foaming agent include inert gases such as carbon dioxide, nitrogen, argon, helium, neon, and astatine. Among these physical foaming agents, a gaseous foaming agent composed of an inert gas such as carbon dioxide, nitrogen, and argon is preferable because it does not need to be vaporized, is inexpensive, and has extremely low risk of environmental pollution and fire. The gaseous foaming agent may be used in a supercritical state.

Examples of the chemical foaming agent include a decomposable foaming agent.
The decomposable foaming agent is generally pre-blended with the raw material resin composition and then supplied to a molding machine, for example, an injection molding machine. Is a compound that decomposes to generate gases such as carbon dioxide and nitrogen. The decomposable foaming agent includes an inorganic decomposable foaming agent and an organic decomposable foaming agent.

Examples of the inorganic decomposable foaming agent include sodium bicarbonate, sodium carbonate, ammonium bicarbonate, ammonium carbonate, and ammonium nitrite.
Examples of the organic decomposable foaming agent include N-nitroso compounds such as N, N′-dinitrosoterephthalamide and N, N′-dinitrosopentamethylenetetramine; azodicarbonamide, azobisisobutyronitrile, azocyclohexyl Azo compounds such as nitrile, azodiaminobenzene, barium azodicarboxylate; benzenesulfonyl hydrazide, toluenesulfonyl hydrazide, p, p'-oxybis (benzenesulfenylhydrazide), diphenylsulfone-3,3'-disulfonylhydrazide, etc. Sulfonyl hydrazide compounds; azide compounds such as 4,4′-diphenyldisulfonyl azide, p-toluenesulfonyl azide and the like.

  These foaming agents may be used alone or in combination of two or more. Further, the foaming agent can be molded after previously blended with a copolymer or copolymer composition, or added separately during molding, for example, when it is injection molded, it should be added from the middle of the cylinder. You can also. Among these foaming agents, carbonates or bicarbonates such as sodium bicarbonate are preferable.

  Moreover, when using the said decomposable foaming agent, you may use together foaming adjuvants, such as organic acid, such as organic acids, such as a citric acid which accelerates | stimulates generation | occurrence | production of gas, and sodium citrate. For example, when using a carbonate or bicarbonate such as sodium bicarbonate as a foaming agent, it is desirable to use an organic carboxylic acid as a foaming aid. The compounding ratio of the carbonate or bicarbonate and the organic carboxylic acid is 30 to 90 parts by weight of the carbonate or bicarbonate and 30 to 90 parts by weight of the total amount of carbonate or bicarbonate and the organic carboxylic acid. A range of 10 to 70 parts by weight of acid is preferred. In addition, in using a foaming agent and a foaming auxiliary agent, the masterbatch containing them may be made beforehand, and you may take the prescription mix | blended with the copolymer or copolymer composition used for foam molding.

  The addition amount of the foaming agent is selected in consideration of the amount of gas generated from the foaming agent and the desired foaming ratio depending on the required properties of the foamed molded product to be produced. It is usually in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the combined composition. When the addition amount of the foaming agent is within such a range, it is possible to obtain a foamed molded article in which the cell diameter is uniform and the cells are uniformly dispersed.

  The foamed molded article of the present invention is prepared by adding a foaming agent to a copolymer or copolymer composition, and plasticizing and kneading with a molding machine, for example, an injection molding machine, to produce a plasticized resin composition, which is foamed. Molding, preferably injection foam molding. The foaming agent may be added to the copolymer or the copolymer composition before being supplied to the injection molding machine. In the injection molding machine in which the copolymer or the copolymer composition is melt-kneaded. You may carry out by supplying a foaming agent.

  Injection foam molding can be roughly divided into two types depending on whether the volume of the cavity is changed during molding. As a method of not changing the cavity volume, the plasticizing resin composition is injected and filled into the mold cavity from the injection molding machine, and then the resin shrinks while keeping the cavity volume constant without moving the mold. With a low-magnification foaming method in which the foaming agent dissolved in the resin is gasified and the inside of the molded body is foamed due to the pressure drop accompanying the molding, it is possible to obtain a molded product with prevention of sink marks and reduced weight by 1 to 20%. it can. In addition, as a method of changing the cavity volume, a molten resin containing a foaming agent is injected and filled, and the cavity volume is increased by moving a movable core or a slide core in the mold in the middle or after completion of injection and filling of the resin. This is a method for producing foamed molded products by foaming a copolymer or copolymer composition by finally changing the volume of the cavity beyond the amount of filled resin. This is a foaming method for obtaining a molded product with greatly improved effects. In this construction method, the foaming ratio can be improved to about 1.1 to 20 times, and the lightening effect in isorigidity can be effectively utilized.

  The foam molded article obtained by the injection foam molding of the present invention can be manufactured by foam molding that does not change the cavity volume, but by a cavity volume expansion method (also called a core back method) in which the cavity volume is expanded by moving the mold. It is preferably manufactured. This construction method will be described below.

A mold used for injection foam molding is composed of a fixed mold and a movable mold, and these are preferably in a mold-clamped state when the plasticized resin composition is injected and filled. When in the mold-clamped state, the position at the time of injection filling of the movable mold, that is, the initial position is the state where the fixed mold and the movable mold are closest to each other, and the foamable resin composition used for one molding There is a movable mold at a position where the volume of the melt is almost equal to the volume filled in an unfoamed state, and a cavity close to the product shape is formed. In the present invention, the length in the expansion direction at the start of injection formed between the fixed mold and the movable mold, that is, the cavity clearance (T ₀ ) of the mold at the start of injection is preferably 0.8-3. The range is 0 mm. If the cavity clearance (T ₀ ) is less than 0.8 mm, the injection filling cavity is narrow, and the plasticized resin composition may not be sufficiently supplied and filled into the cavity due to an increase in viscosity or solidification of the plasticized resin composition. For example, even if injection filling is performed at a high pressure to sufficiently fill such a thin cavity, the mold will open as a result of the resin pressure in the cavity increasing significantly and exceeding the mold clamping force of the molding machine. In some cases, burrs may be generated, and thin molding itself may not be performed. Further, when performing such thin-wall molding, the resin temperature is significantly cooled, so that even if the cavity volume is increased, foaming does not occur sufficiently, resulting in poor foaming. Even in the case of thin molding of less than 0.8 mm, shot shots can be solved by having a thick portion to flow the molten resin in a part of the molded product. It may become impossible to obtain the light weight effect of molding itself.

  Further, the rigidity of the foam molded product can be improved by improving the elastic modulus of the material itself, but the rigidity can also be increased by increasing the thickness of the foam molded article. Therefore, if you want to increase the rigidity of a flat part or only part of it, increase the initial thickness of the molded product to increase the thickness after foaming and improve the rigidity, or form ribs and bosses on the back of the molded product By doing so, it is possible to improve the rigidity, or to reduce foaming by reducing the plate thickness, thereby adjusting the partial rigidity and impact of the molded product.

  In addition, in foam molding, which is performed by moving the mold as described this time, the rigidity is improved by the effect of increasing the plate thickness by foaming in the direction perpendicular to the direction of movement of the mold, but almost foaming is achieved in the direction of movement of the mold. There is almost no change in thickness and no change in thickness, and improvement in rigidity cannot be expected. Therefore, it is necessary to widen the initial cavity clearance and secure rigidity with the initial resin filling thickness.

Therefore, when you want to improve partial rigidity and impact, or when you want to obtain the light weight reduction effect required for molded products with a three-dimensional shape, injection of 0.8 mm to 3.0 mm that can be foamed optimally It is desirable to have a cavity clearance (T ₀ ) region at the start in the mold cavity of 50% or more, more preferably 60% or more, and even more preferably 70% or more.

  The injection time of the plasticized resin composition into the mold cavity is not particularly limited, but is preferably about 0.7 to 5.0 s, preferably 0 to 5 s after completion of injection. It is desirable to provide time and then expand the cavity volume. By providing this delay time, the thickness of the skin layer can be controlled, and when the delay time is lengthened, the skin layer can be thickened, and as a result, mechanical properties such as rigidity can be enhanced. Here, the enlargement ratio of the cavity volume is usually 1.1 to 5.0 times.

Further, T ₀ and the ratio (T ₁ / T ₀₎ between the expansion direction length of the cavity of the section after the movable mold retracted (T ₁₎ is 1.1 or more. When T ₁ / T ₀ is less than 1.1, it is the same as an unfoamed molded article, and a desired rigidity cannot be obtained.

  The mold partition wall moving speed when expanding the cavity volume varies depending on the thickness of the molded body, the type of resin, the type of foaming agent, the mold temperature, and the resin temperature.For example, in the case of injection foam molding using ordinary polypropylene, 0.5-100 mm / s is preferable. If the core moving speed is too slow, the resin solidifies in the middle of the cavity volume expansion, and sufficient foaming ratio cannot be obtained.If the core moving speed is too fast, the cell generation / growth does not follow the core movement, and the cell breaks down and the appearance looks There is a possibility that a good molded article cannot be obtained.

  The temperature of the resin to be injected and the mold temperature vary depending on the thickness of the molded body, the type of resin, the type and amount of the foaming agent, etc., but the temperatures usually used for molding propylene-based resins are sufficient, and the product thickness is In order to obtain a thin product or a product with a high expansion ratio, it is preferable to set it higher than the normal mold temperature. Specifically, for example, the temperature of the injected resin is 170 to 250 ° C. The mold temperature of the fixed mold and the movable mold is 10 to 100 ° C. The resin pressure in the mold is 5 to 200 MPa. The injection needs to be performed with a mold clamping force between the fixed mold and the movable mold at an injection pressure higher than the resin pressure in the cavity, and the injection pressure is usually 10 to 250 MPa.

  As in the present invention, after filling the cavity with the resin composition at one time and then foaming, the resin in the part in contact with the mold is solidified faster than the resin inside and the unfoamed skin layer on the surface of the molded product Can be formed. Thereby, a hard product shape can be obtained and maintained, and a highly rigid molded product can be obtained. Moreover, even if some distribution occurs in the cell shape, cell density, and expansion ratio inside the molded body, a molded body having a good appearance can be obtained due to the smoothness and rigidity of the skin layer. The thickness of the skin layer is not particularly limited, but is preferably 0.1 mm or more. The timing of expanding the cavity volume to form the skin layer with the above thickness depends on the type of resin, the type of foaming agent, the mold temperature, and the resin temperature, but when normal polypropylene is used, after completion of injection filling To about 0 to 5 s. If the time from completion of injection filling to the expansion of the cavity volume is too short, a skin layer with sufficient thickness will not be formed, and if it is too long, the resin will solidify and a sufficient expansion ratio will be obtained even if the cavity volume is expanded. I can't.

  The expansion ratio should be appropriately controlled by the resin temperature, injection speed, waiting time from the end of injection filling to the start of cavity volume expansion, the amount of partition movement when the cavity volume is expanded, the partition wall movement speed, the cooling time after the end of cavity volume expansion, etc. Usually 1.1 to 5.0 times. The cavity volume can be expanded in several stages, whereby a molded body with a controlled cell structure and end shape can be obtained.

  In the present invention, a hot runner, a shut-off nozzle, a valve gate, etc. that are used in normal injection molding can also be used. Valve gates and hot runners not only suppress the generation of waste resin such as runners, but also prevent the occurrence of defects in foamed molded products in the next cycle by leakage of the propylene resin composition for foam molding from the mold into the cavity. effective.

  After completion of foaming, it can be cooled as it is and the foamed molded product can be taken out, or the molding cycle can be shortened by controlling the contact state between the molded product and the mold by slightly clamping, thereby promoting cooling. It is also possible to obtain a molded article having a good dent and cell shape.

  Since the resin composition used for the foam of the present invention can increase the expansion ratio as compared with a general propylene-based resin composition, the rigidity improving effect and the degree of freedom of the shape of the molded product are easily increased.

  Moreover, according to this invention, the injection foaming molded object whose thickness is about 1.0-15.0 mm can be obtained suitably, for example. The average cell diameter of this injection-foamed molded product is about 0.01 to 1.0 mm, but depending on the shape and application of the molded product, even if the cell diameter is several mm, part of the cells communicated. May be partially present. In particular, when the expansion ratio is increased, the cells meet together and communicate with each other, and the inside of the molded body becomes hollow. However, since the resin pillars are formed in the cavity, the molded body is highly lightweight. And has a strong rigidity. Such foamed molded products can be suitably used for various applications such as automotive interior and exterior parts, cardboard substitutes, electrical appliances, building materials, etc., and particularly suitable for automotive interior parts and automotive exterior parts. Can be used.

The present invention will be described more specifically based on examples, but the present invention is not limited to these examples.
In addition, the physical-property value etc. in an Example and a comparative example were measured with the following method.

[Various measurement conditions in Examples]
[Comonomer composition]
The contents of propylene, α-olefin and non-conjugated polyene in the propylene copolymer were measured by ¹³ C-NMR and ¹ H-NMR.

[Intrinsic viscosity [η]]
The intrinsic viscosity [η] was measured at 135 ° C. using a decalin solvent.
[Molecular weight distribution (Mz / Mw)]
The molecular weight distribution is a liquid chromatograph (Waters) in which TSKgelGMH ⁶ -HT × 2 and TSKgelGMH ⁶ -HTL × 2 columns (both column sizes are 7.5 mm in diameter and 300 mm in length) are connected in series as columns. Measurement was performed using an alliance / GPC2000 type). The obtained chromatogram was analyzed using a calibration curve using a standard polystyrene sample by a known method using the data processing software Empower2 manufactured by Waters, and Mz / Mw was calculated.

[MFR (g / 10 min)]
MFR was measured according to JIS K-6721 with a load of 2.16 kg at 230 ° C. and a load of 10 kg at 230 ° C.

From the measurement result, the ratio (MFR ₁₀ / MFR _2.16 ) was calculated.
(Linear viscoelasticity measurement)
A press sheet having a thickness of 2 mm was punched into a disk shape of 25 mmφ and used as a sample. MCR301 (rheometer) manufactured by ANTONPaar was used for measurement, and a 25 mmφ parallel plate was used as the jig.

From the measurement results, the ratio (η * ₎ between the complex viscosity η * ₍ ω _{= 0.1)} at the frequency (ω = _0.1 rad / s) and the complex viscosity η * ₍ ω _{= 100)} at the frequency (ω = 100 rad / s). ₍ ω _{= 0.1)} / η * ₍ ω _{= 100)} ) was calculated.

[Melting tension (MT: mN)]
Capillograph 1C (barrel diameter 9.55 mmφ) manufactured by Toyo Seiki Co., Ltd., barrel temperature 230 ° C., capillary length (L) = 8.0 mm, capillary diameter (D) = 2.095 mm, L / D = 3.82 capillary Was measured at a piston speed of 15.0 mm / min and a winding speed of 15.0 mm / min, and the average value of the obtained values was taken as the melt tension.

[Methods for preparing various measurement samples for the composition]
Tri (2,4-di-t-butylphenyl) phosphate as a secondary antioxidant is added to the total of 100 parts by weight of the propylene-based copolymers (A), (B) and (C). 1 part by weight, 0.1 part by weight of pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] as a heat stabilizer, and 0. 0 of calcium stearate as a hydrochloric acid absorbent. 1 part by weight was blended. Thereafter, using a kneader ruder (biaxial melt kneader) manufactured by Musashinokikai Co., Ltd., at a set temperature of 200 ° C., melted and kneaded for 5 minutes at a set amount of 1.5 kg, 20 rpm, pelletized, and taken out with a cooling press set at 20 ° C. did. This was cut into an appropriate size to obtain a measurement sample.

[Density (g / cm ³ ) and foaming ratio]
The obtained molded body and foam were cut into appropriate shapes, and density measurement was carried out by an underwater displacement method (based on JISK7112) using an electronic hydrometer (manufactured by Alpha Mirage, MD-200S).

The value obtained by dividing the density of the press sheet before foaming by the density of the molded article after foaming was taken as the foaming ratio.
[Fusibility in foamed molded products]
The obtained foamed molded product was cut, and the fusing property was evaluated by observing the fracture surface when the foam was broken from the cut portion.

○: There is no breakage at the boundary of the pre-foamed particle, and the material breakage of the pre-foamed particle is caused. △: Breakage at the boundary of the pre-foamed particle and the material breakage are mixed. Cell diameter (μm)]
After cutting the cross section of the foam sample with a razor and depositing platinum on the cross section with an auto fine coater (JFC-1600) manufactured by JEOL Ltd., a scanning electron microscope manufactured by JEOL Ltd. ( JSM-6510LV) was used to observe the cross section, and the cell diameter was measured.

[50% compressive strength (kPa)]
According to JIS K6767, the 50% compressive strength of the obtained pre-expanded particle foam molded article was measured under the conditions of a test piece temperature of 23 ° C. and a load speed of 10 mm / min.

[Flatness]
The flatness of the molded body was evaluated by cutting the molded body on a diagonal line and comparing the plate thickness at three division points when the gap between the gate portion and the end portion was equally divided into four.

○: Plate thickness error of the entire molded body is less than ± 0.2 mm Δ: Plate thickness error of the entire molded body is ± 0.2 mm or more and less than 0.3 mm ×: Plate thickness error of the entire molded body is ± 0.3 mm or more [ (Flow Mark / Swirl Mark)
The flow mark and swirl mark of the injection molded product were evaluated by visual observation of the surface of the molded product. In this test, in order to make it easy to determine the flow mark and swirl mark, 3 parts by weight of a black colored masterbatch is dry blended with 100 parts by weight of a propylene-based copolymer or copolymer composition, and then injected. Molding was performed.

○: Conspicuous swirl mark and flow mark are not seen on the molded product surface ×: Swirl mark and flow mark can be clearly confirmed on the molded product surface

[Cell shape]
SEM observation of the cross-section of the foam sheet was performed, and the case where adjacent bubbles were independent from each other was evaluated as independent bubbles and the case where they were connected as communication.

[Example 1]
A SUS polymerization apparatus with a stirring blade with a capacity of 1500 ml that was sufficiently purged with nitrogen was charged with 750 ml of dry hexane, 10 ml of 5-vinyl-2-norbornene, and 0.75 mmol of triisobutylaluminum (TIBAl) at 23 ° C. at room temperature. The internal temperature of the polymerization apparatus was raised to 80 ° C., 200 ml of hydrogen was inserted, the internal pressure was increased to 0.5 MPa with propylene, and the internal pressure was adjusted to 0.55 MPa with ethylene.

  Next, di (p-chlorophenyl) methylene (cyclopentadienyl) (octamethyloctahydrodibenzofluorenyl) zirconium dichloride 0.0005 mmol and 0.0025 mmol of triphenylcarbenium tetrakis (pentafluorophenyl) borate were added in the polymerization vessel. Polymerization was carried out for 10 minutes while maintaining the internal temperature at 80 ° C. and the internal pressure at 0.55 MPa, and 20 ml of methanol was added to terminate the polymerization. After depressurization, the polymer was precipitated from the polymerization solution in 4 L of methanol and dried under vacuum at 130 ° C. for 12 hours. The obtained propylene copolymer (A-1) was 21.6 g. The physical properties of the polymer are shown in Table 1.

〔実施例２〕（Ｘ−１）
プロピレン系共重合体（Ａ-１）２０重量部と、プロピレン系共重合体（Ｂ-１）（プライムポリマー社製プライムポリプロ Ｊ１３６、ＭＦＲ（２３０℃、２．１６ｋｇ荷重）＝２２．３（ｇ／１０分）、Ｔｍ＝１６２℃）８０重量部を用いて、上記組成物に対する各種測定用サンプルの作製法によりプレスシートを作成して、物性を測定した。各種物性結果を表２に示す。

[Example 2] (X-1)
20 parts by weight of propylene copolymer (A-1) and propylene copolymer (B-1) (Prime Polymer Co., Ltd. Prime Polypro J136, MFR (230 ° C., 2.16 kg load) = 22.3 (g / 10 minutes), Tm = 162 ° C.) Using 80 parts by weight, a press sheet was prepared by a method for preparing various measurement samples for the composition, and the physical properties were measured. Table 2 shows the results of various physical properties.

[Comparative Example 1] (X-2)
20 parts by weight of propylene copolymer (C-1) (Tafmer P0775 manufactured by Mitsui Chemicals, MFR (230 ° C., 2.16 kg load) = 0.6 (g / 10 min)), and propylene copolymer (B -1) Using 80 parts by weight, a press sheet was prepared in the same manner as in Example 2, and the physical properties were measured. Table 2 shows the results of various physical properties.

[Comparative Example 2] (X-3)
Using 100 parts by weight of the propylene copolymer (B-1), a press sheet was prepared in the same manner as in Example 2, and the physical properties were measured. Table 2 shows the results of various physical properties.

[Manufacture of pre-expanded particle foam moldings]
[Example 3, Comparative Examples 3 and 4] (foams 1 to 3)
100 parts by weight (1.5 kg) of 2 mg / pellet of each of the propylene polymer compositions (X-1) and (X-2) and the propylene copolymer (X-3) were stirred. Put in a pressure vessel with an internal volume of 10 liters, and 300 parts by weight of water and 0.3 part by weight of precipitated barium sulfate (average particle size 0.7 μm) manufactured by Sakai Chemical Industry Co., Ltd. as a dispersant and Wako Jun as a dispersion aid 0.05 parts by weight of sodium 1-dodecanesulfonate manufactured by Yakuhin Kogyo Co., Ltd. was added to obtain a dispersion of resin particles. While stirring the dispersion, 15 parts by weight of liquid carbon dioxide was added, and the dispersion was heated to 156 ° C. At this time, gaseous carbon dioxide gas was added to maintain the internal pressure of the pressure vessel at 3.0 to 3.2 MPa (gauge pressure), and held for 15 minutes. Next, one end of the pressure vessel was opened, and the contents were released under atmospheric pressure to obtain pre-expanded particles. During the discharge of the pre-expanded particles from the pressure vessel, the pressure was released while supplying nitrogen gas into the pressure vessel so that the pressure inside the pressure vessel was kept at the pressure immediately before the release. The obtained pre-foamed particles were washed with water, dried, allowed to stand at atmospheric pressure for 24 hours and then cured, and then the density and expansion ratio of the pre-foamed particles were measured. Next, the pre-expanded particles were filled into a 230 mm × 140 mm × 50 mm mold and heated with water vapor of 0.3 to 0.25 MPa (gauge pressure) to be molded. After the foamed molded body of the pre-expanded particles obtained was cured in an oven at 70 ° C. for 24 hours, the fusion state between the foamed particles in the molded body was measured. The respective evaluation results are shown in Table 3.

〔実施例４〕（Ｘ−４）
プロピレン系共重合体（Ａ-１）２０重量部と、プロピレン系共重合体（Ｂ-２）（プライムポリマー社製プライムポリプロ Ｊ-３０００ＧＶ（Ｂ-２）、ＭＦＲ（２３０℃、２．１６ｋｇ荷重）＝３９（ｇ／１０分）、Ｔｍ＝１６２℃））８０重量部を用いて、実施例２と同様にして、プレスシートを作成して、物性を測定した。各種物性結果を表４に示す。

[Example 4] (X-4)
20 parts by weight of propylene-based copolymer (A-1), propylene-based copolymer (B-2) (Prime Polymer Co., Ltd. Prime Polypro J-3000GV (B-2), MFR (230 ° C., 2.16 kg load) ) = 39 (g / 10 min), Tm = 162 ° C.)) Using 80 parts by weight, a press sheet was prepared in the same manner as in Example 2, and the physical properties were measured. Table 4 shows the results of various physical properties.

[Comparative Example 5] (X-5)
Propylene-based copolymer (C-2) (Mitsui Chemicals Tuffmer A1085 (C-2), MFR (230 ° C., 2.16 kg load) = 2.3 (g / 10 min), Tm = 73 ° C.) 20 weight A press sheet was prepared in the same manner as in Example 2 using 80 parts by weight and 80 parts by weight of the propylene copolymer (B-2), and the physical properties were measured. Table 4 shows the results of various physical properties.

[Comparative Example 6] (X-6)
Using 100 parts by weight of the propylene copolymer (B-2), a press sheet was prepared in the same manner as in Example 2, and the physical properties were measured. Table 4 shows the results of various physical properties.

[Manufacture of Injection Foam Molded Body] (Foam 4 to 6)
[Example 5, Comparative Examples 7 and 8] (Foams 4 to 6)
In each pellet of the propylene polymer composition (X-4), (X-5) and propylene copolymer (X-6), 6 parts by weight of a chemical foaming agent master batch, Polyslen EE275F manufactured by Eiwa Kasei Co., Ltd. Were dry blended and injection molded under the following conditions to obtain a foam molded article. The respective evaluation results are shown in Table 5.

(Injection foam molding conditions)
・ Injection molding machine: Ube Industries, Ltd., MD350S-III type (clamping force 350t)
・ Die Cavity Size: Vertical 400mm, Horizontal 200mm, Cavity Clearance 1.2mm between Fixed Die and Movable Die
Gate: Single point direct gate in the cavity Injection temperature: 210 ° C
Mold surface temperature: 45 ° C
Injection time: 1.0 s (Time from the start of injection to the end of injection of molten resin)
-Foam molding conditions Cavity clearance (T) between fixed mold and movable mold after foaming process: 3.0 mm
Bulkhead moving speed when the cavity volume is expanded: 20 mm / s
Foam start delay time after resin filling: 0 to 1 s
Cavity clearance (T ₀ ) between fixed mold and movable mold at the start of injection: 1.2 mm

Claims (14)

A structural unit derived from propylene [i] 50 to 95 mol%, a structural unit derived from an α-olefin having 2 to 10 carbon atoms excluding propylene [ii] 4.9 to 49.9 mol%, and a non-conjugated polyene Derived structural unit [iii] 0.1 to 10 mol% (provided that the total of structural units [i], [ii] and [iii] is 100 mol%), and
A propylene-based copolymer (A) characterized by satisfying the following requirements (a) and (c).
(A) The intrinsic viscosity [η] measured at 135 ° C. in decalin is 0.1 to 5.0 (dL / g),
(C) MFR ₁₀ obtained at 230 ° C. and 10 kg load according to JIS K-6721, and MFR _2.16 obtained at 230 ° C. and 2.16 kg load according to JIS K-6721 Ratio (MFR ₁₀ / MFR _2.16 ) is 8.0 to 150.0. The propylene-based copolymer (A) according to claim 1, further satisfying the following requirements (b) and (d).
(B) The ratio (Mz / Mw) of z-average molecular weight (Mz) and weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) is 3.0 to 20.0,
(D) Complex viscosity η * ₍ ω _{= 0.1)} of frequency (ω = _0.1 rad / s) obtained by linear viscoelasticity measurement (190 ° C.) using a rheometer, and frequency (ω = 100 rad / s) ) To the complex viscosity η * ₍ ω _{= 100)} (η * ₍ ω _{= 0.1)} / η * ₍ ω _{= 100)} ) is 5 to ₁₀₀ .   5 to 95 parts by weight of the propylene-based copolymer (A) according to claim 1 or 2 and 5 to 95 parts by weight of a thermoplastic resin (B) (however, the total of (A) and (B) is 100 weights) A propylene-based copolymer composition (X). At least selected from ethylene, 1-butene, 4-methylpentene-1, 1-hexene and 1-octene, satisfying the following requirements (a) to (d) and derived from propylene: 50 to 95 mol% 4.9 to 49.9 mol% of structural units derived from one or more α-olefins and 0.1 to 10 mol% of structural units derived from 5-vinyl-2-norbornene (provided that the structural unit [i ), [Ii] and [iii] as 100 mol% in total) 5 to 80 parts by weight of propylene-based copolymer (A1),
95 to 20 parts by weight of polypropylene (B1) (provided that the total of (A1) and (B1) is 100 parts by weight), and
A propylene-based copolymer composition (X1) characterized by satisfying the following requirement (xa).
(A) The intrinsic viscosity [η] measured at 135 ° C. in decalin is 0.1 to 5.0 (dL / g),
(B) The ratio (Mz / Mw) of z-average molecular weight (Mz) and weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) is 3.0 to 20.0,
(C) MFR10 obtained at 230 ° C. and 10 kg load according to JIS K-6721, and MFR2.16 obtained at 230 ° C. and 2.16 kg load according to JIS K-6721 Ratio (MFR10 / MFR2.16) is 8.0 to 150.0,
(D) Complex viscosity η * (ω = 0.1) of frequency (ω = 0.1 rad / s) obtained by linear viscoelasticity measurement (190 ° C.) using a rheometer, and frequency (ω = 100 rad) / S) to the complex viscosity η * (ω = 100) (η * (ω = 0.1) / η * (ω = 100)) is 5 to 100,
(Xa) Ratio of the melt tension MT (X1) at 230 ° C. of the propylene-based copolymer composition (X1) to the melt tension MT (B1) at 230 ° C. of the polypropylene (B1) (MT (X1) / MT ( B1)) is 2.0 to 10.0.   The molded object obtained using the propylene-type polymer of Claim 1 or 2.   The molded object obtained using the propylene-type polymer composition of Claim 3 or 4.   A pre-foamed particle foam molded article obtained by filling pre-foamed particles obtained using the propylene-based copolymer according to claim 1 or 2 into a mold and heating and foaming.   A pre-expanded particle foam molded article obtained by filling pre-expanded particles obtained using the propylene-based copolymer composition according to claim 3 or 4 in a mold and heating and foaming.   An injection foam molded article obtained by an injection molding method using the propylene-based copolymer according to claim 1 or 2.   An injection foam molded article obtained by an injection molding method using the propylene-based copolymer composition according to claim 3 or 4.   The manufacturing method of the pre-expanded particle expansion molding obtained using the propylene-type copolymer of Claim 1 or 2.   The manufacturing method of the pre-expanded particle expansion molding obtained using the propylene-type copolymer composition of Claim 3 or 4.   A method for producing an injection-foamed molded article comprising the propylene-based copolymer according to claim 1 or 2, using an injection molding machine.   A method for producing an injection-foamed molded article comprising the propylene-based copolymer composition according to claim 3 or 4, using an injection molding machine.