JP5162323B2 - Extrusion foam molding resin composition and foam using the same - Google Patents

Description

  The present invention relates to a resin composition for extrusion foam molding and a foam using the same, and more particularly, extrusion suitable for obtaining a highly closed cell structure having uniform and fine foam cells even at a high magnification. The present invention relates to a resin composition for foam molding and a foam excellent in buffering property, appearance and odor resistance obtained by using the resin composition.

  Propylene resins have been proposed as foams to replace polystyrene resins. Propylene resins generally have high crystallinity, and the melt viscosity during extrusion is difficult to adjust. It is difficult to obtain a good product because the foamed cell diameter tends to be non-uniform. For example, a foam with a low expansion ratio of about 2 or 3 times can improve the foam molding performance by increasing the strain-hardening property of melt tension or elongational viscosity, but has a high expansion ratio. In the body, with the conventional propylene-based resin, it is difficult to obtain a closed cell structure having uniform and fine foam cells. It is generally known that the higher the magnification of the foam, the better the buffering, heat insulation, and sound absorbing properties, and the closed cell structure that forms the interior of the foam can further improve these characteristics, so at high magnification There is a need for a foam having an excellent closed cell structure.

  In order to solve such problems, as a technique for increasing the melt tension of the propylene resin to be used and obtaining uniform and fine foam cells, free end long chain branching by electron beam radiation is applied to the propylene resin. Proposals have also been made to obtain a very special propylene-based resin (see Patent Documents 1 and 2). Such a propylene-based resin is said to be suitable for obtaining a low-density foam excellent in closed cell ratio and appearance.

However, since the propylene-based resin has a high crystallization speed, it has a poor ability to hold fine bubbles at the time of molding, and in the point of obtaining a foam having an excellent closed cell structure consisting of uniform fine foam cells. It was not enough. Furthermore, since the crystallization speed is high, the proper molding temperature range at which a good foam can be obtained was narrow. In addition, since the propylene-based resin has undergone a special reforming process, it is not economical and has a problem of odor, and the resin itself undergoes a crosslinking reaction. It is generated in large quantities and has the disadvantage that its recycling is difficult.
Japanese Patent Laid-Open No. 62-121704 JP-A-2-69533

  An object of the present invention is to provide a resin composition for extrusion foam molding suitable for obtaining a highly closed cell structure having uniform and fine foam cells even at a high magnification in view of the current state of the prior art, and the use thereof Another object of the present invention is to provide a foam excellent in buffering property, appearance and odor resistance.

  As a result of intensive studies to solve the above problems, the present inventors have found that an extrusion foam molding resin composition containing a specific amount of a foaming agent with respect to a specific propylene polymer (X) is extruded. In foam molding, it is suitable for obtaining a highly closed cell structure having uniform and fine foam cells even at a high magnification, and the foam obtained by using the foam has cushioning properties, appearance and odor resistance. As a result, the present invention has been completed.

That is, according to the first invention of the present invention, it is composed of the following component (A) that is insoluble in p-xylene at 25 ° C. and component (B) that is soluble in p-xylene at 25 ° C. ) The weight average molecular weight (Mw) measured by GPC is 100,000 to 1,000,000, (ii) the component insoluble in hot p-xylene is 0.3% by weight or less, and (iii) strain in measurement of elongational viscosity. Curing degree (λmax) is 2.0 or more, (iv) MFR (230 ° C., 2.16 kg load) is 0.1 to 20 g / 10 min, and (v) Melt tension tester measurement at 230 ° C. There is provided an extrusion foam molding resin composition comprising a propylene polymer (X) having a melt tension (MT) of 5 g or more and a foaming agent.
Component (A): Component (CXIS) that is insoluble in p-xylene at 25 ° C. having the requirements defined in the following (A1) to (A5).
(A1) It is 20 to 95 weight% with respect to the polymer (X) whole quantity.
(A2) The weight average molecular weight (Mw) measured by GPC is 100,000 to 1,000,000.
(A3) The isotactic triad fraction (mm) measured by ¹³ C-NMR is 93% or more.
(A4) The strain hardening degree (λmax) in the measurement of elongational viscosity is 2.0 or more.
(A5) A propylene unit and an ethylene unit or an α-olefin unit are contained.
Component (B): Component (CXS) that dissolves in p-xylene at 25 ° C. having the requirements defined in the following (B1) to (B3).
(B1) 5 to 80% by weight based on the total amount of the polymer (X).
(B2) The weight average molecular weight (Mw) measured by GPC is 100,000 to 1,000,000.
(B3) Contains propylene units, ethylene units and / or α-olefin units.

According to the second invention of the present invention, in the first invention, the component (B) of the propylene-based polymer (X) further has (B4) a strain hardening degree (λmax) of 2. There is provided a resin composition for extrusion foam molding characterized by having a requirement of being 0 or more.
According to the third invention of the present invention, in the first invention, the propylene polymer (X) has a crystalline propylene polymer segment as a side chain and an amorphous propylene copolymer segment as a main chain. There is provided a resin composition for extrusion foam molding characterized by being composed of a polymer having a branched structure.
Furthermore, according to the fourth aspect of the present invention, in the first aspect, the component (A) of the propylene polymer (X) has a crystalline propylene polymer segment as a side chain, and an amorphous propylene copolymer segment. A resin composition for extrusion foam molding is provided, which is composed of a polymer having a branched structure having a main chain as a main chain.

According to the fifth invention of the present invention, in the first invention, the component (A) of the propylene polymer (X) contains an ethylene unit and has an ethylene content of 0.1 to 10. A resin composition for extrusion foam molding is provided, which is characterized by the weight percent.
Furthermore, according to the sixth invention of the present invention, in the first invention, the component (B) of the propylene-based polymer (X) contains an ethylene unit and has an ethylene content of 10 to 60% by weight. A resin composition for extrusion foam molding is provided.

  Moreover, according to 7th invention of this invention, the foam characterized by obtaining the resin composition for extrusion foam molding which concerns on any one of 1st-6th invention by extrusion molding is provided.

According to an eighth aspect of the present invention, there is provided a foam according to the seventh aspect, wherein the foaming ratio is 5 to 40 times and the open cell ratio is 20% or less. .
Furthermore, according to the ninth aspect of the present invention, there is provided the foam according to the seventh or eighth aspect, wherein the average cell diameter is 400 μm or less.

As described above, the present invention relates to a resin composition for extrusion foam molding, and the preferred embodiments include the following.
(1) In the first invention, the foaming agent is sodium bicarbonate, ammonium carbonate, ammonium nitrite, azide compound (azodicarbonamide, azobisformamide, isobutyronitrile, diazoaminobenzene, etc.) or nitroso compound (N, N'-dinitrosopentatetramine, N, N'-dimethyl-dinitroterephthalamide, etc.) or a volatile foam selected from carbon dioxide, nitrogen, water or alkane gas (butane, etc.) A resin composition for extrusion foam molding, which is an agent.
(2) In any one of the above inventions, the amount of the foaming agent is 0.01 to 15.0 parts by weight with respect to 100 parts by weight of the propylene polymer (X). Resin composition.

  The resin composition for extrusion foam molding of the present invention is obtained by blending a foaming agent with a specific propylene polymer (X), is highly crystalline, has a slow crystallization rate, and has a melt flow. Since it has good characteristics and high melt tension and high strain hardening, it is suitable for obtaining a highly closed cell structure having uniform and fine foam cells even at a high expansion ratio. And the foam obtained by extrusion foam molding using it is more excellent in compression characteristics, buffer properties, heat insulation, appearance, cleanliness, recyclability, impact resistance and odor resistance. It can be suitably used for heat-shrinkable shrink labels such as glass bottles, metal cans and plastic bottles, individual packaging such as hygiene products and cosmetics, food containers and the like.

The resin composition for extrusion foam molding of the present invention comprises the following component (A) that is insoluble in p-xylene at 25 ° C. and component (B) that is soluble in p-xylene at 25 ° C., and (i) The weight average molecular weight (Mw) measured by GPC is 100,000 to 1,000,000, (ii) the component insoluble in hot p-xylene is 0.3% by weight or less, and (iii) strain hardening in the measurement of elongational viscosity. Degree (λmax) is 2.0 or more, (iv) MFR (230 ° C., 2.16 kg load) is 0.1 to 20 g / 10 min, and (v) melting at 230 ° C. as measured by a melt tension tester. A foaming agent is blended with the propylene polymer (X) having a tension (MT) of 5 g or more.
Component (A): Component (CXIS) that is insoluble in p-xylene at 25 ° C. having the requirements defined in the following (A1) to (A5).
(A1) It is 20 to 95 weight% with respect to the polymer (X) whole quantity.
(A2) The weight average molecular weight (Mw) measured by GPC is 100,000 to 1,000,000.
(A3) The isotactic triad fraction (mm) measured by ¹³ C-NMR is 93% or more.
(A4) The strain hardening degree (λmax) in the measurement of elongational viscosity is 2.0 or more.
(A5) A propylene unit and an ethylene unit or an α-olefin unit are contained.
Component (B): Component (CXS) that dissolves in p-xylene at 25 ° C. having the requirements defined in the following (B1) to (B3).
(B1) 5 to 80% by weight based on the total amount of the polymer (X).
(B2) The weight average molecular weight (Mw) measured by GPC is 100,000 to 1,000,000.
(B3) Contains propylene units, ethylene units and / or α-olefin units.

Hereinafter, the components of the resin composition for extrusion foam molding, the production thereof, and the foam obtained using the same will be described in detail.
I. 1. Components of resin composition for extrusion foam molding Propylene polymer (X)
The propylene-based polymer (X) constituting the resin composition for extrusion foam molding of the present invention comprises a component (A) that is insoluble in p-xylene at 25 ° C. and a component (B) that is soluble in p-xylene at 25 ° C. And (i) a weight average molecular weight (Mw) measured by GPC is 100,000 to 1,000,000, and (ii) a component insoluble in hot p-xylene is 0.3% by weight or less ( iii) the strain hardening degree (λmax) in the measurement of the extensional viscosity is 2.0 or more, (iv) the MFR (230 ° C., 2.16 kg load) is 0.1 to 20 g / 10 min, and (v) the melt The melt tension (MT) at 230 ° C. measured by a tension tester is 5 g or more.

  The propylene polymer (X) includes a crystalline propylene polymer component and a propylene-ethylene containing a copolymer in which a crystalline propylene polymer segment and a part of an amorphous propylene copolymer segment are chemically bonded. It is a propylene-ethylene copolymer component obtained by sequentially producing a random copolymer component by a multistage polymerization method.

The multistage polymerization is preferably a two-stage polymerization in which the crystalline propylene polymer component is polymerized in the first stage and the propylene-ethylene random copolymer component is polymerized in the second stage.
At this time, a part of the crystalline propylene polymer produced in the first step is present in a state in which a part of the reaction is terminated in the state of the terminal vinyl group, so that when the second-stage polymerization is performed as it is, the terminal vinyl is As a macromonomer, the crystalline propylene polymer is involved in the second stage polymerization, the non-crystalline propylene copolymer segment (propylene-ethylene random copolymer segment) is the main chain, and the crystalline propylene polymer segment is the side chain. A copolymer having a certain branched structure is formed.
The present inventors consider that the factor that the propylene-based copolymer (X) according to the present invention exhibits a good uniform fine foaming property can be attributed to the presence of this branched structure. In general, a polymer having a part composed of a chain of different monomers in one molecule, such as a real block copolymer or a graft copolymer, is a molecule that is considerably smaller than an ordinary phase separation structure, called a microphase separation structure. It is known to have a phase separation structure on the order of level, and such a fine phase separation structure significantly improves uniform fine foamability. Actually, in the electron micrographs (FIGS. 3 and 4) of the propylene-based polymer (X) (copolymer having a branched structure) according to the present invention, ordinary resins (those having no branched structure (FIG. 5)) In comparison with the above, a very fine dispersion structure of rubber domains is seen, which supports the above inference.
The propylene polymer (X) is a copolymer having a branched structure in which an amorphous propylene copolymer segment (propylene-ethylene random copolymer segment) is a main chain, and a crystalline propylene polymer segment is a side chain. Is included. In addition to propylene and ethylene, the component constituting the main chain may contain other unsaturated compounds, for example, α-olefins such as 1-butene, as long as the essence of the present invention is not significantly impaired. The component constituting the side chain is mainly propylene, and may contain a small amount of other unsaturated compounds, for example, α-olefins such as ethylene and 1-butene, as long as the essence of the present invention is not significantly impaired. Good.

As one of the techniques for determining whether or not there is a graft copolymer in which the propylene-ethylene random copolymer component as described above is a main chain and the crystalline propylene polymer component is a side chain, It is effective to use the strain hardening degree (λmax) obtained from the measurement of the extensional viscosity.
The strain hardening degree (λmax) is an index representing the strength at the time of melting, and when this value is large, there is an effect of improving the melt tension.
The degree of strain hardening is an index representing the nonlinearity of elongational viscosity, and it is usually said that this value increases as the molecular entanglement increases. Molecular entanglement is affected by the amount of branching and the length of the branched chain. Therefore, the greater the amount of branching and the length of branching, the greater the degree of strain hardening.
In the propylene polymer (X) according to the present invention, a terminal propylene polymer of a vinyl group is involved in the polymerization as a macromonomer during the production of the first crystalline propylene polymer, and a branched propylene polymer is formed. To do. Therefore, this degree of strain hardening is an index of the amount of terminal vinyl propylene polymer produced, and is preferably 2.0 or more.
Here, as to the method for measuring the strain hardening degree, the same value can be obtained in principle by any method as long as the uniaxial elongation viscosity can be measured. 42 (2001) 8663, and preferable measuring methods and measuring instruments include the following.

Measuring method 1:
Apparatus: Ales manufactured by Rheometrics
Jig: EXTENSIONAL VISUALITY FIXTURE, manufactured by TA Instruments
Measurement temperature: 180 ° C
Strain rate: 0.1 / sec
Preparation of test piece: A sheet of 18 mm × 10 mm and a thickness of 0.7 mm is formed by press molding.

Measurement method 2:
Apparatus: Toyo Seiki Co., Ltd., Melten Rheometer
Measurement temperature: 180 ° C
Strain rate: 0.1 / sec
Preparation of test piece: Extruded strands are prepared at a speed of 10 to 50 mm / min using an orifice with an inner diameter of 3 mm at 180 ° C. using a Capillograph manufactured by Toyo Seiki Co., Ltd.

Calculation method:
The elongational viscosity at a strain rate of 0.1 / sec is plotted as a log-log graph of time t (second) on the horizontal axis and elongational viscosity ηE (Pa · second) on the vertical axis. On the logarithmic graph, the viscosity immediately before strain hardening is approximated by a straight line, the maximum value (ηmax) of the extensional viscosity ηE until the amount of strain becomes 4.0 is obtained, and on the approximate straight line up to that time Let ηlin be the viscosity.
FIG. 2 is an example of a plot of elongational viscosity. ηmax / ηlin is defined as λmax and is used as an index of strain hardening degree.
The elongational viscosity and strain hardening degree calculated from the measuring method 1 and the measuring method 2 are, in principle, for measuring the inherent extensional viscosity and strain hardening degree of the substance and exhibit the same value. Therefore, either measurement method 1 or measurement method 2 may be used.

However, the measurement method 2 has a measurement restriction that a measurement sample hangs down when the molecular weight is relatively low (that is, when MFR> 2), and the measurement accuracy is lowered. In measurement method 1, when measuring a relatively high molecular weight (MFR <1), the measurement sample is deformed in a non-uniform manner, and distortion occurs at the time of measurement. There is a problem of measurement accuracy that is averaged and the strain hardening degree is estimated to be small.
Therefore, it is preferable for convenience to use the measuring method 1 for those having a low molecular weight and the measuring method 2 for those having a high molecular weight.
In general, in order to show a high degree of strain hardening, it is said that the entanglement molecular weight (Me) of 7000 or more of polypropylene is preferred as the branch length, and that the degree of strain hardening increases as the branch length increases.

The propylene-based polymer (X) according to the present invention is separated into a crystalline component and an amorphous component, and the amount of the component (B) dissolved in paraxylene at 25 ° C. is based on the total amount of the propylene-based polymer (X). The amount of the component (A) that is 5 to 80% by weight and insoluble in paraxylene is 20 to 95% by weight.
Here, a specific method for separating the crystalline component and the amorphous component is as follows.

Sorting method:
A sample of 2 g was dissolved in 300 ml of p-xylene (0.5 mg / ml BHT: 2,6-di-tert-butyl-4-methylphenol included) at 130 ° C. to obtain a solution, and then at 25 ° C. Leave for 48 hours. Thereafter, it is separated into a precipitated polymer and a filtrate. The p-xylene is evaporated from the filtrate and further dried under reduced pressure at 100 ° C. for 12 hours, and the component (CXS) dissolved in xylene at 25 ° C. is recovered. In addition, the precipitated polymer similarly removes the remaining p-xylene sufficiently, and becomes a component insoluble in xylene (CXIS) at 25 ° C.

As described above, the propylene polymer (X) is composed of a crystalline component (A) and an amorphous component (B), and a part of each component is a propylene-ethylene random copolymer segment. Is a main chain, and includes a copolymer having a branched structure in which the crystalline propylene polymer segment is a side chain, and analytically, the following characteristics (i) to (v), (A1) to (A5) ), (B1) to (B3).
(I): The weight average molecular weight (Mw) measured by GPC of the propylene polymer (X) is 100,000 to 1,000,000.
(Ii): The amount of components insoluble in hot paraxylene of the propylene polymer (X) is 0.3% by weight or less based on the total amount of the propylene polymer (X).
(Iii): The strain hardening degree (λmax) in the measurement of the extensional viscosity of the propylene polymer (X) is 2.0 or more.
(Iv): The MFR of the propylene polymer (X) is 0.1 to 20 g / 10 min.
(V) The melt tension (MT) at 230 ° C. measured by a melt tension tester is 5 g or more.
(A1): The amount of the component (A) is 20 to 95% by weight with respect to the total amount of the propylene polymer (X).
(A2): The weight average molecular weight (Mw) measured by GPC of a component (A) is 100,000-1 million.
(A3): Isotactic triad fraction (mm) measured by ¹³ C-NMR of component (A) is 93% or more.
(A4): The strain hardening degree (λmax) in the measurement of the extensional viscosity of the component (A) is 2.0 or more.
(A5): Component (A) contains a propylene unit and an ethylene unit or an α-olefin unit.
(B1): The amount of component (B) is 5 to 80% by weight based on the total amount of polymer (X).
(B2): The weight average molecular weight (Mw) measured by GPC of a component (B) is 100,000-1 million.
(B3) The component (B) contains a propylene unit, an ethylene unit and / or an α-olefin unit.

Hereinafter, each item will be described sequentially.
(I): The weight average molecular weight (Mw) measured by GPC of the propylene polymer (X) is 100,000 to 1,000,000.
As the propylene polymer (X), those having a weight average molecular weight in the range of 100,000 to 1,000,000 are used.
The weight average molecular weight (Mw) is measured by a GPC measuring apparatus and conditions described later, and it is necessary that the Mw of the propylene polymer (X) is in the range of 100,000 to 1,000,000. When this Mw is smaller than 100,000, the melt processability is inferior and the mechanical strength is insufficient. On the other hand, when the Mw exceeds 1 million, the melt viscosity is high and the melt processability is lowered. From the balance of melt processability and mechanical strength, it is in the above range, preferably Mw is 150,000 to 900,000, more preferably 200,000 to 800,000.
The weight average molecular weight (Mw) measured by GPC of the propylene polymer (X) can be adjusted by controlling the temperature and monomer pressure, which are the polymerization conditions of the propylene polymer (X), or by propylene polymerizing a chain transfer agent such as hydrogen. Adjustments can be made easily by controlling the amount of hydrogen added at times.
The weight average molecular weight (Mw) value, the number average molecular weight (Mn) value, and the Q value (Mw / Mn) are obtained by gel permeation chromatography (GPC). Details are as follows.

Equipment: GPC manufactured by Waters (ALC / GPC, 150C)
Detector: MIRAN, 1A, IR detector manufactured by FOXBORO (measurement wavelength: 3.42 μm)
Column: AD806M / S (3 pieces) manufactured by Showa Denko KK
Mobile phase solvent: o-dichlorobenzene (ODCB)
Measurement temperature: 140 ° C
Flow rate: 1.0 ml / min Injection volume: 0.2 ml

The sample is prepared by preparing a 1 mg / mL solution using ODCB (containing 0.5 mg / mL BHT) and dissolving it at 140 ° C. for about 1 hour. The baseline and section of the obtained chromatogram are performed as shown in FIG. Further, the conversion from the retention capacity obtained by GPC measurement to the molecular weight is performed using a standard curve prepared in advance by standard polystyrene. The standard polystyrenes used are all the following brands manufactured by Tosoh Corporation.
Brand: F380, F288, F128, F80, F40, F20, F10, F4, F1, A5000, A2500, A1000
Inject 0.2 mL of a solution dissolved in ODCB (containing 0.5 mg / mL BHT) so that each is 0.5 mg / mL to create a calibration curve. The calibration curve uses a cubic equation obtained by approximation by the least square method. Viscosity formula used for conversion to molecular weight: [η] = K × M ^α uses the following numerical values.
PS: K = 1.38 × 10 ⁻⁴ , α = 0.7
PP: K = 1.03 × 10 ⁻⁴ , α = 0.78

(Ii): The amount of components insoluble in hot paraxylene of the propylene-based polymer (X) is 0.3% by weight or less based on the total amount of the polymer (X).
In the present invention, the component insoluble in hot p-xylene needs to be 0.3% by weight or less. If the component insoluble in hot p-xylene exceeds 0.3% by weight, the resulting molded article may be adversely affected such as perforations and bumps.
A method for measuring a component insoluble in hot p-xylene is as follows.
A glass separable flask equipped with a stirrer is charged with 500 mg of a polymer in a bowl made of stainless steel 400 mesh (wire diameter 0.03 μm, aperture 0.034 mm, space ratio 27.8%). Fixed to. 700 ml of p-xylene containing 1 g of an antioxidant (BHT: 2,6-di-t-butyl-4-methylphenol) was added, and the polymer was dissolved while stirring at a temperature of 140 ° C. for 2 hours.
The soot containing the p-xylene insoluble part was collected, sufficiently dried and weighed to obtain the paraxylene insoluble part. The gel fraction (% by weight) defined as the p-xylene insoluble part was calculated by the following formula.
Gel fraction = [(residual amount in mesh g) / (prepared sample amount g)] × 100

Further, in order to have a small amount of gel or no gel as described above, it is important that there are no components having a very high molecular weight. Therefore, when the molecular weight distribution is measured by GPC, it is important that the molecular weight distribution does not spread to the high molecular weight side.
Therefore, the Q value (the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn)) measured by GPC is preferably 7 or less, more preferably 6 or less, and still more preferably 5 or less.
Moreover, in order not to extend extremely to the high molecular weight side, it is necessary that the molecular weight M (90) at which the integrated value in the curve is 90% by GPC is 2,000,000 or less.
Here, M (90) is a molecular weight at which the integral value in the curve is 90% by GPC measured by the GPC measuring apparatus and conditions described above, and in the present invention, M (90) is 2,000,000 or less. It is a feature. When M (90) exceeds 2,000,000, the high molecular weight component is excessively increased, and a gel is generated or melt processability is deteriorated. Therefore, M (90) is 2,000,000 or less, preferably 1,500,000 or less, and more preferably 1,000,000.
The amount of components insoluble in hot paraxylene is controlled by adjusting the temperature and monomer pressure, which are the polymerization conditions of the propylene-based polymer (X), or by controlling the amount of hydrogen added to add a chain transfer agent such as hydrogen during propylene polymerization. Adjustments can be made easily.

(Iii): The strain hardening degree (λmax) in the measurement of the extensional viscosity of the propylene polymer (X) is 2.0 or more.
The physical significance of the strain hardening degree is as described above. If this value is large, the closed cell ratio can be increased when foam molding is performed. Therefore, this strain hardening degree needs to be 2.0 or more, preferably 3.0 or more, more preferably 4.0 or more.
The length of branching is preferably an entanglement molecular weight of 7000 or more of polypropylene. Strictly speaking, this molecular weight is different from the weight average (Mw) measured by GPC. Therefore, the weight average molecular weight (Mw) value measured by GPC is preferably 15000 or more, and more preferably 30000 or more.
The strain hardening degree (λmax) in the measurement of the extensional viscosity of the propylene-based polymer (X) is the selection of the metallocene complex described later, the combination thereof, and the amount thereof used in the polymerization of the propylene-based polymer (X). Adjustments can be made by controlling the ratio and prepolymerization conditions. For example, one of the two types of metallocene complexes is selected so as to easily generate a macromer, and the other is selected so that the macromer can be easily incorporated into the polymer and can generate a high molecular weight polymer. Furthermore, by performing prepolymerization, it can be adjusted by a method such as uniformly distributing long chain branches among polymer particles.

(Iv): The MFR of the propylene polymer (X) is 0.1 to 20 g / 10 min.
When the melt flow rate (MFR) of the propylene polymer (X) is less than 0.1 g / 10 minutes, the fluidity is lowered. On the other hand, when the MFR exceeds 20 g / 10 min, the melt processability decreases. Moreover, within this range, it is preferably 0.1 to 15 g / 10 minutes, more preferably 1 to 10 g / 10 minutes, and particularly preferably 1 to 5 g / 10 minutes.
Here, MFR is a value measured according to JIS K7210 at a heating temperature of 230 ° C. and a load of 21.2 N (2.16 kg).
The melt flow rate (MFR) of the propylene polymer (X) is a hydrogen that adjusts the temperature and the monomer pressure, which are the polymerization conditions of the propylene polymer (X), or adds a chain transfer agent such as hydrogen during propylene polymerization. Adjustment can be easily performed by controlling the amount of addition.

(V): The melt tension (MT) at 230 ° C. of the propylene-based polymer (X) is 5 g or more.
When the melt tension (MT) at 230 ° C. measured by the melt tension tester of the propylene-based polymer (X) is less than 5 g, it is difficult to obtain a uniform fine foam, whereas the melt tension (MT) exceeds 100 g. If so, the stretchability of the resulting foam may be deteriorated.
The melt tension (MT) at 230 ° C. in the measurement of the melt tension tester of the propylene-based polymer (X) is preferably 6 to 100 g, more preferably 10 to 90 g, and particularly preferably 15 to 80 g.
The melt tension (MT) of the propylene polymer (X) can be adjusted by increasing or decreasing the high molecular weight component and increasing or decreasing the number of branches. That is, the adjustment can be performed by controlling the selection of the metallocene complex described later, the combination thereof, the amount ratio thereof, and the prepolymerization conditions used in the polymerization of the propylene-based polymer (X). For example, one of the two types of metallocene complexes is selected so as to easily generate a macromer, and the other is selected so that the macromer can be easily incorporated into the polymer and can generate a high molecular weight polymer. Furthermore, by performing prepolymerization, it can be adjusted by a method such as uniformly distributing long chain branches among polymer particles.

(A1): The amount of the component (A) is 20 to 95% by weight with respect to the total amount of the propylene polymer (X).
This rule is a range with respect to the total amount of the propylene-based polymer (X) of the component (A), and those in this range are used from the balance of rigidity and impact resistance.

(A2): The weight average molecular weight (Mw) measured by GPC of a component (A) is 100,000-1 million.
Here, the weight average molecular weight (Mw) is measured by the GPC measuring apparatus and conditions described above, and the crystalline component (A) in the propylene polymer (X) has a weight average molecular weight of 100,000 to Those in the range of 1 million are used.
When this Mw is smaller than 100,000, the melt processability is inferior and the mechanical strength is insufficient. On the other hand, when the Mw exceeds 1 million, the melt viscosity is high and the melt processability is lowered. From the balance of melt processability and mechanical strength, it is in the above range, preferably Mw is 150,000 to 900,000, more preferably 200,000 to 800,000.
The weight average molecular weight (Mw) can be easily adjusted by adjusting the temperature and monomer pressure, which are the polymerization conditions of the propylene polymer (X), or by controlling the amount of hydrogen added to the chain transfer agent such as hydrogen during propylene polymerization. Adjustments can be made.

(A3): Isotactic triad fraction (mm) measured by ¹³ C-NMR of component (A) is 93% or more.
The crystalline component (A) of the propylene polymer (X) according to the present invention has a stereoregularity in which the mm fraction of propylene unit three-chains obtained by ¹³ C-NMR is 93% or more.
The mm fraction is the ratio of three propylene unit chains in which the direction of methyl branching in each propylene unit is the same among arbitrary three propylene unit chains composed of head-to-tail bonds in the polymer chain. This mm fraction is a value indicating that the three-dimensional structure of the methyl group in the polypropylene molecular chain is controlled isotactically, and the higher the value, the higher the degree of control. When the mm fraction of the crystalline component (A) is smaller than this value, the mechanical properties such as the elastic modulus, rigidity, heat resistance and strength of the resulting foam are lowered. Accordingly, the mm fraction is preferably 95% or more, and more preferably 96% or more.
The isotactic triad fraction (mm) measured by ¹³ C-NMR of the propylene polymer (X) can be adjusted by the selection of the metallocene complex described later, the polymerization temperature and the polymerization pressure.

The detail of the measuring method of mm fraction of the propylene unit 3 chain | strand by ¹³ C-NMR is as follows.
A sample of 375 mg was completely dissolved in 2.5 ml of deuterated 1,1,2,2-tetrachloroethane in an NMR sample tube (10φ), and then measured at 125 ° C. by a proton complete decoupling method. The chemical shift was set to 74.2 ppm in the middle of the three peaks of deuterated 1,1,2,2-tetrachloroethane. The chemical shift of other carbon peaks is based on this.
Flip angle: 90 degrees Pulse interval: 10 seconds Resonance frequency: 100 MHz or more Integration frequency: 10,000 times or more Observation range: -20 ppm to 179 ppm

The mm fraction is measured using a ¹³ C-NMR spectrum measured under the above conditions.
Spectra assignment is made according to the method described in detail in Japanese Patent Application No. 2006-311249, with reference to Macromolecules, (1975) 8 pp. 687, Polymer, 30 pages, 1350 (1989). Do.

(A4): The strain hardening degree (λmax) in the measurement of the extensional viscosity of the component (A) is 2.0 or more. Preferably it is 3.0 or more, More preferably, it is 4.0 or more.
The length of branching is preferably an entanglement molecular weight of 7000 or more of polypropylene. Moreover, as a weight average (Mw), it is 15000 or more, More preferably, it is 30000 or more.
The strain hardening degree (λmax) in the measurement of the extensional viscosity of the propylene-based polymer (X) is the selection of the metallocene complex described later, the combination thereof, and the amount thereof used in the polymerization of the propylene-based polymer (X). Adjustments can be made by controlling the ratio and prepolymerization conditions. For example, one of the two types of metallocene complexes is selected so as to easily generate a macromer, and the other is selected so that the macromer can be easily incorporated into the polymer and can generate a high molecular weight polymer. Furthermore, by performing prepolymerization, it can be adjusted by a method such as uniformly distributing long chain branches among polymer particles.

The propylene polymer (X) according to the present invention satisfies (A5) in addition to the above (A1) to (A4).
(A5): Component (A) contains a propylene unit and an ethylene unit or an α-olefin unit.
As a unit constituting the crystalline component (A), it is necessary that propylene is arranged in an isotactic manner and has crystallinity. Further, ethylene or α-olefin may be contained as a comonomer unit within the range where crystallinity is exhibited. If α, ω-diene units are present, gelation due to cross-linking is a concern, so it is necessary that no α, ω-diene units be included.
As a kind of comonomer, ethylene or a linear alpha olefin is preferable, More preferably, it is ethylene.
Regarding comonomer content, it can contain arbitrary quantity in the range which crystallinity expresses.

The melting point (Tm) measured by DSC, which is an index of crystallinity, is 120 ° C. or higher, preferably 150 ° C. or higher, more preferably 153 ° C. or higher. When the melting point (Tm) is 150 to 164 ° C., it is excellent in heat resistance and rigidity and can be used for industrial parts and members, and when the melting point (Tm) is 120 to 150 ° C., it is excellent in flexibility and can be used for containers.
The ethylene content of component (A) is preferably 0.1 to 10% by weight, more preferably 0.2 to 7% by weight, and still more preferably 0.3 to 5% by weight.
The ethylene unit is measured according to the method described in Macromolecules 1982 1150 using ¹³ C-NMR.

(B1): The amount of component (B) is 5 to 80% by weight based on the total amount of polymer (X).
This rule is a range with respect to the total amount of the propylene polymer (X) of the component (B), and those in this range are used from the balance of rigidity and impact resistance.

(B2): The weight average molecular weight (Mw) measured by GPC of a component (B) is 100,000-1 million.
Here, the weight average molecular weight (Mw) is measured by the GPC measuring apparatus and conditions described above, and the amorphous component (B) in the propylene polymer (X) has a weight average molecular weight of 100,000. Those in the range of ~ 1 million are used.
When this Mw is smaller than 100,000, the melt processability is inferior and the mechanical strength is insufficient. On the other hand, when the Mw exceeds 1 million, the melt viscosity is high and the melt processability is lowered. From the balance of melt processability and mechanical strength, it is in the above range, preferably Mw is 150,000 to 900,000, more preferably 200,000 to 800,000.
The weight average molecular weight (Mw) can be easily adjusted by adjusting the temperature and monomer pressure, which are the polymerization conditions of the propylene polymer (X), or by controlling the amount of hydrogen added to the chain transfer agent such as hydrogen during propylene polymerization. Adjustments can be made.

(B3): Component (B) contains a propylene unit, an ethylene unit and / or an α-olefin unit.
As a unit constituting the amorphous component (B), it is necessary that propylene and ethylene or α-olefin are copolymerized. Moreover, since there exists a concern about the gelatinization by bridge | crosslinking when an (alpha), (omega) -diene unit exists, it is preferable not to contain an (alpha), (omega) -diene unit.
The kind of comonomer is preferably ethylene or a linear α-olefin, more preferably ethylene, and the ethylene content is usually 10 to 60% by weight. From the viewpoint of improving impact resistance at low temperatures, 40 to 60% by weight is preferable, and from the viewpoint of gloss and transparency, 10% by weight or more and less than 40% by weight is preferably used.

(B4): The strain hardening degree (λmax) in the measurement of the extensional viscosity of the component (B) is 2.0 or more.
As described above, if the degree of strain hardening (λmax) is large, the closed cell ratio can be increased when foam molding is performed. Therefore, when using it for foam molding, 2.0 or more are preferable and 2.0-20 are still more preferable.
The strain hardening degree (λmax) in the measurement of the extensional viscosity of the propylene-based polymer (X) is the selection of the metallocene complex described later, the combination thereof, and the amount thereof used in the polymerization of the propylene-based polymer (X). Adjustments can be made by controlling the ratio and prepolymerization conditions. For example, one of the two types of metallocene complexes is selected so as to easily generate a macromer, and the other is selected so that the macromer can be easily incorporated into the polymer and can generate a high molecular weight polymer. Furthermore, by performing prepolymerization, it can be adjusted by a method such as uniformly distributing long chain branches among polymer particles.

Regarding the method for producing the propylene polymer (X) according to the present invention, a macromer having a vinyl terminal can be produced, and a catalyst system capable of copolymerizing the macromer with propylene and ethylene may be used. It is a feature. Among them, by using a polymerization catalyst obtained by contacting the following catalyst components (a), (b) and (c),
(I) first step of polymerizing propylene alone, or propylene and ethylene or α-olefin, and polymerizing ethylene or α-olefin with respect to all monomer components in an amount of 0 to 10% by weight; and (ii) propylene and ethylene Or a second step in which α-olefin is polymerized and ethylene is polymerized in an amount of 10 to 70% by weight based on the total monomer components;
The propylene-based polymer (X) according to the present invention can be produced with high productivity by the process having the above.

(1) Component (a):
The catalyst component (a) used for the production of the propylene polymer (X) is a metallocene compound having hafnium as a central metal represented by the following general formula (1).

In general formula (1), each R ₁ is independently hydrogen, an alkyl group having 1 to 6 carbon atoms, a halogen-containing alkyl group having 1 to 6 carbon atoms, a silicon-containing alkyl group having 1 to 6 carbon atoms, or carbon. An aryl group having 6 to 16 carbon atoms, a halogen-containing aryl group having 6 to 16 carbon atoms, a nitrogen or oxygen having 4 to 16 carbon atoms, and a heterocyclic group containing sulfur, and at least one of two R ₁ is carbon A heterocyclic group containing nitrogen, oxygen, or sulfur of several 4 to 16 is shown. Two R _{1 s} may be the same or different from each other. Each R ₂ is independently an alkyl group having 1 to 6 carbon atoms, a halogen-containing alkyl group having 1 to 6 carbon atoms, a silicon-containing alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 16 carbon atoms. , A halogen-containing aryl group having 6 to 16 carbon atoms, a silicon-containing aryl group having 6 to 16 carbon atoms, a nitrogen or oxygen having 6 to 16 carbon atoms, and a heterocyclic group containing sulfur. Two R ₂ may be the same as or different from each other.
X and Y are each independently a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a silicon-containing hydrocarbon group having 1 to 20 carbon atoms, or a halogenated hydrocarbon having 1 to 20 carbon atoms. Represents a group, an oxygen-containing hydrocarbon group having 1 to 20 carbon atoms, an amino group, or a nitrogen-containing hydrocarbon group having 1 to 20 carbon atoms, Q is a divalent hydrocarbon group having 1 to 20 carbon atoms, 1 carbon atom Represents a silylene group, an oligosilylene group, or a germylene group which may have ˜20 hydrocarbon groups.

The heterocyclic group containing nitrogen, oxygen or sulfur having 4 to 16 carbon atoms of R ₁ is preferably a 2-furyl group, a substituted 2-furyl group, a substituted 2-thienyl group, or a substituted 2 group. -Furfuryl group, more preferably a substituted 2-furyl group.
Moreover, as a substituted 2-furyl group, a substituted 2-thienyl group, and a substituted 2-furfuryl group, an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, and a propyl group, Examples thereof include halogen atoms such as fluorine atom and chlorine atom, alkoxy groups having 1 to 6 carbon atoms such as methoxy group and ethoxy group, and trialkylsilyl groups. Of these, a methyl group and a trimethylsilyl group are preferable, and a methyl group is particularly preferable.
R ₁ is particularly preferably a 2- (5-methyl) -furyl group. Moreover, it is preferable that two R ₁ are mutually the same.

R ₂ is preferably an aryl group having 6 to 16 carbon atoms, a halogen-containing aryl group having 6 to 16 carbon atoms, or a silicon-containing aryl group having 6 to 16 carbon atoms. Such an aryl group has 6 to 16 carbon atoms. 1 or more hydrocarbon groups having 1 to 6 carbon atoms, silicon-containing hydrocarbon groups having 1 to 6 carbon atoms, and halogen-containing hydrocarbon groups having 1 to 6 carbon atoms on the aryl cyclic skeleton. You may have as a substituent.
R ₂ is preferably at least one of phenyl group, 4-tbutylphenyl group, 2,3-dimethylphenyl group, 3,5-ditbutylphenyl group, 4-phenyl-phenyl group, chlorophenyl group, naphthyl. Group, or a phenanthryl group, more preferably a phenyl group, a 4-tbutylphenyl group, or a 4-chlorophenyl group. Moreover, the case where two R < ₂ > is mutually the same is preferable.

In general formula (1), X and Y are each independently a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, a halogenated hydrocarbon group having 1 to 20 carbon atoms, or a carbon number of 1 to 20 A silicon-containing hydrocarbon group, an oxygen-containing hydrocarbon group having 1 to 20 carbon atoms, an amino group, or a nitrogen-containing hydrocarbon group having 1 to 20 carbon atoms. As said halogen atom, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned.
Specific examples of the hydrocarbon group having 1 to 20 carbon atoms include alkyl groups such as methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, and s-butyl, vinyl, propenyl, Examples include alkenyl groups such as cyclohexenyl, arylalkyl groups such as benzyl, arylalkenyl groups such as trans-styryl, and aryl groups such as phenyl, tolyl, 1-naphthyl, and 2-naphthyl.
Specific examples of the oxygen-containing hydrocarbon group having 1 to 20 carbon atoms include alkoxy groups such as methoxy, ethoxy, propoxy, and butoxy, allyloxy groups such as phenoxy and naphthoxy, arylalkoxy groups such as phenylmethoxy, and furyl groups. And oxygen-containing heterocyclic groups.
Specific examples of the nitrogen-containing hydrocarbon group having 1 to 20 carbon atoms include alkylamino groups such as methylamino, dimethylamino, ethylamino and diethylamino, arylamino groups such as phenylamino and diphenylamino, (methyl) ( (Alkyl) (aryl) amino groups such as phenyl) amino, and nitrogen-containing heterocyclic groups such as pyrazolyl and indolyl.

In the halogenated hydrocarbon group having 1 to 20 carbon atoms, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The halogenated hydrocarbon group is a compound in which, when the halogen atom is, for example, a fluorine atom, the fluorine atom is substituted at an arbitrary position of the hydrocarbon group. Specific examples include fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, and trichloromethyl groups.
Specific examples of the silicon-containing hydrocarbon group having 1 to 20 carbon atoms include trialkylsilylmethyl groups such as trimethylsilylmethyl and triethylsilylmethyl, dialkyl such as dimethylphenylsilylmethyl, diethylphenylsilylmethyl, and dimethyltolylsilylmethyl. (Alkyl) (aryl) silylmethyl group and the like can be mentioned.

In general formula (1), Q is a divalent hydrocarbon group having 1 to 20 carbon atoms and a silylene group optionally having a hydrocarbon group having 1 to 20 carbon atoms, which binds two five-membered rings. , Either an oligosilylene group or a germylene group. When two hydrocarbon groups are present on the above-mentioned silylene group, oligosilylene group or germylene group, they may be bonded to each other to form a ring structure.
Specific examples of Q include alkylene groups such as methylene, methylmethylene, dimethylmethylene, 1,2-ethylene; arylalkylene groups such as diphenylmethylene; silylene groups; methylsilylene, dimethylsilylene, diethylsilylene, di ( n-propyl) silylene, di (i-propyl) silylene, alkylsilylene groups such as di (cyclohexyl) silylene, (alkyl) (aryl) silylene groups such as methyl (phenyl) silylene; arylsilylene groups such as diphenylsilylene; tetra An alkyl oligosilylene group such as methyldisilylene; a germylene group; an alkylgermylene group in which the silicon of the above-mentioned divalent hydrocarbon group having 1 to 20 carbon atoms is replaced with germanium; (alkyl) (aryl) germylene Group; arylgermylene group It can be mentioned. In these, the silylene group which has a C1-C20 hydrocarbon group, or the germylene group which has a C1-C20 hydrocarbon group is preferable, and an alkylsilylene group and an alkylgermylene group are especially preferable.

Of the compounds represented by the general formula (1), preferred compounds are specifically exemplified below.
Dimethylsilylenebis (2- (2-furyl) -4-phenyl-indenyl) hafnium dichloride, dimethylsilylenebis (2- (2-thienyl) -4-phenyl-indenyl) hafnium dichloride, dimethylsilylenebis (2- (2 -(5-methyl) -furyl) -4-phenyl-indenyl) hafnium dichloride, diphenylsilylenebis (2- (2- (5-methyl) -furyl) -4-phenyl-indenyl) hafnium dichloride, dimethylgermylenebis (2- (2- (5-Methyl) -furyl) -4-phenyl-indenyl) hafnium dichloride, dimethylgermylenebis (2- (2- (5-methyl) -thienyl) -4-phenyl-indenyl) hafnium Dichloride, dimethylsilylenebis (2- (2- (5-t Butyl) -furyl) -4-phenyl-indenyl) hafnium dichloride, dimethylsilylenebis (2- (2- (5-trimethylsilyl) -furyl) -4-phenyl-indenyl) hafnium dichloride, dimethylsilylenebis (2- (2 -(5-phenyl) -furyl) -4-phenyl-indenyl) hafnium dichloride, dimethylsilylenebis (2- (2- (4,5-dimethyl) -furyl) -4-phenyl-indenyl) hafnium dichloride, dimethylsilylene Bis (2- (2-benzofuryl) -4-phenyl-indenyl) hafnium dichloride, diphenylsilylenebis (2- (2- (5-methyl) -furyl) -4-phenyl-indenyl) hafnium dichloride, dimethylsilylenebis ( 2- (2- (5-Methyl -Furyl) -4-methyl-indenyl) hafnium dichloride, dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4-isopropyl-indenyl) hafnium dichloride, dimethylsilylenebis (2- (2-furfuryl) ) -4-phenyl-indenyl) hafnium dichloride, dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4- (4-chlorophenyl) -indenyl) hafnium dichloride, dimethylsilylenebis (2- (2 -(5-Methyl) -furyl) -4- (4-fluorophenyl) -indenyl) hafnium dichloride, dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4- (4-trifluoromethyl) Phenyl) -indenyl) hafnium dichloride, dimethylsilylenebi (2- (2- (5-methyl) -furyl) -4- (4-t-butylphenyl) -indenyl) hafnium dichloride, dimethylsilylenebis (2- (2-furyl) -4- (1-naphthyl) ) -Indenyl) hafnium dichloride, dimethylsilylenebis (2- (2-furyl) -4- (2-naphthyl) -indenyl) hafnium dichloride, dimethylsilylenebis (2- (2-furyl) -4- (2-phenanthryl) ) -Indenyl) hafnium dichloride, dimethylsilylenebis (2- (2-furyl) -4- (9-phenanthryl) -indenyl) hafnium dichloride, dimethylsilylenebis (2- (2- (5-methyl) -furyl)- 4- (1-naphthyl) -indenyl) hafnium dichloride, dimethylsilylenebis (2- (2 (5-Methyl) -furyl) -4- (2-naphthyl) -indenyl) hafnium dichloride, dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4- (2-phenanthryl) -indenyl) Hafnium dichloride, dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4- (9-phenanthryl) -indenyl) hafnium dichloride, dimethylsilylenebis (2- (2- (5-t-butyl) -Furyl) -4- (1-naphthyl) -indenyl) hafnium dichloride, dimethylsilylenebis (2- (2- (5-t-butyl) -furyl) -4- (2-naphthyl) -indenyl) hafnium dichloride, Dimethylsilylenebis (2- (2- (5-t-butyl) -furyl) -4- (2-phenanthryl) -indene ) Hafnium dichloride, dimethylsilylene bis (2- (2- (5-t-butyl) -furyl) -4- (9-phenanthryl) -indenyl) hafnium dichloride, dimethylsilylene (2-methyl-4-phenyl-indenyl) ) (2- (2- (5-methyl) -furyl) -4-phenyl-indenyl) hafnium dichloride, dimethylsilylene (2-methyl-4-phenyl-indenyl) (2- (2- (5-methyl)- And thienyl) -4-phenyl-indenyl) hafnium dichloride.

  Of these, more preferred are dimethylsilylene bis (2- (2- (5-methyl) -furyl) -4-phenyl-indenyl) hafnium dichloride, dimethylgermylene bis (2- (2- (5-methyl). ) -Thienyl) -4-phenyl-indenyl) hafnium dichloride, dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4- (4-chlorophenyl) -indenyl) hafnium dichloride, dimethylsilylenebis (2 -(2- (5-methyl) -furyl) -4-naphthyl-indenyl) hafnium dichloride, dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4- (4-t-butylphenyl) -Indenyl) hafnium dichloride, dimethylsilylene (2-methyl-4-phenyl-indenyl) ( - (2- (5-methyl) - furyl) -4-phenyl - indenyl) hafnium dichloride.

  Also particularly preferred are dimethylsilylene bis (2- (2- (5-methyl) -furyl) -4-phenyl-indenyl) hafnium dichloride, dimethylsilylene bis (2- (2- (5-methyl) -furyl). ) -4-naphthyl-indenyl) hafnium dichloride, dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4- (4-t-butylphenyl) -indenyl) hafnium dichloride.

(2) Component (b):
Next, the catalyst component (b) is an ion-exchange layered silicate.
In the present invention, an ion-exchange layered silicate (hereinafter sometimes abbreviated as silicate) has a crystal structure in which surfaces formed by ionic bonds and the like are stacked in parallel with each other by a binding force, and , Refers to a silicate compound in which the contained ions are exchangeable. Most silicates are naturally produced mainly as the main component of clay minerals, and are generally dispersed / swelled in water and purified by differences in sedimentation rate, etc., but they can be completely removed. Although it may be difficult and contains impurities (quartz, cristobalite, etc.) other than ion-exchangeable layered silicate, they may be included. Depending on the type, amount, particle size, crystallinity, and dispersion state of these impurities, it may be preferable to pure silicate, and such a complex is also included in component (b).
In addition, the raw material of this invention refers to the silicate of the previous stage which performs the chemical treatment of this invention mentioned later. Further, the silicate used in the present invention is not limited to a natural product, and may be an artificial synthetic product.
In addition, in the present invention, if there is ion exchange properties before chemical treatment, the physical and chemical properties are changed by the treatment, and silicates having no ion exchange properties or layer structures are also included. Treated as an ion-exchanged layered silicate.

Specific examples of the ion-exchange layered silicate include, for example, layered silicates having a 1: 1 type structure or a 2: 1 type structure described in Haruo Shiramizu “Clay Mineralogy” Asakura Shoten (1988) and the like. Can be mentioned.
The 1: 1 type structure is based on the stacking of the 1: 1 layer structure in which one layer of tetrahedron sheet and one layer of octahedron sheet are combined as described in the above “clay mineralogy” and the like. The 2: 1 type structure is a structure based on a stack of 2: 1 layer structures in which two layers of tetrahedral sheets sandwich one layer of octahedral sheets.

Specific examples of ion-exchangeable layered silicates in which the 1: 1 layer is the main constituent layer include kaolin silicates such as dickite, nacrite, kaolinite, metahalloysite, halloysite, chrysotile, risardite, antigolite, etc. Examples include serpentine silicates.
Specific examples of ion-exchangeable layered silicates in which the 2: 1 layer is the main constituent layer include smectite group silicates such as montmorillonite, beidellite, nontronite, saponite, hectorite, stevensite, vermiculite, etc. Examples thereof include vermiculite silicates, mica, illite, sericite, and mica group silicates such as sea chlorite, attapulgite, sepiolite, palygorskite, bentonite, pyrophyllite, talc, and chlorite. These may form a mixed layer.
Among these, the main component is preferably an ion-exchange layered silicate having a 2: 1 type structure. More preferably, the main component is a smectite group silicate, and still more preferably, the main component is montmorillonite.

  The type of interlayer cations (cations contained between the layers of the ion-exchange layered silicate) is not particularly limited, but as a main component, alkali metals of the first group of the periodic table such as lithium and sodium, calcium and magnesium Alkali earth metals of Group 2 of the periodic table, etc., or transition metals such as iron, cobalt, copper, nickel, zinc, ruthenium, rhodium, palladium, silver, iridium, platinum, gold, etc. are relatively It is preferable in that it can be easily obtained.

  The ion-exchange layered silicate may be used in a dry state or in a slurry state in a liquid. In addition, the shape of the ion-exchange layered silicate is not particularly limited, and may be a naturally produced shape, a shape when artificially synthesized, or a shape by operations such as pulverization, granulation, and classification. You may use the processed ion exchange layered silicate. Of these, the granulated ion-exchange layered silicate is particularly preferable because it gives good polymer particle properties when the ion-exchange layered silicate is used as a catalyst component.

Processing of the shape of the ion-exchange layered silicate such as granulation, pulverization, and classification may be performed before the chemical treatment (that is, the following chemical treatment is performed on the ion-exchange layered silicate that has been processed in advance). The shape may be processed after chemical treatment.
Examples of the granulation method used here include stirring granulation method, spray granulation method, rolling granulation method, briquetting, compacting, extrusion granulation method, fluidized bed granulation method, emulsion granulation method. , Submerged granulation method, compression molding granulation method, and the like, but are not particularly limited. Preferably, agitation granulation method, spray granulation method, rolling granulation method, and fluidized granulation method are exemplified, and particularly preferably, agitation granulation method and spray granulation method are exemplified.
When spray granulation is performed, water or an organic solvent such as methanol, ethanol, chloroform, methylene chloride, pentane, hexane, heptane, toluene, and xylene is used as a dispersion medium for the raw slurry. Preferably, water is used as a dispersion medium. The concentration of the component (b) in the raw slurry liquid for spray granulation from which spherical particles are obtained is 0.1 to 30% by weight, preferably 0.5 to 20% by weight, particularly preferably 1 to 10% by weight. . The inlet temperature of the hot air for spray granulation from which spherical particles are obtained varies depending on the dispersion medium, but is 80 to 260 ° C, preferably 100 to 220 ° C when water is taken as an example.

  In granulation, in order to obtain a carrier having high particle strength and to improve propylene polymerization activity, the silicate is refined as necessary. The silicate may be refined by any method. As a method for miniaturization, either dry pulverization or wet pulverization is possible. Preferably, wet pulverization using water as a dispersion medium and utilizing the swellability of silicate, for example, a method using forced stirring using polytron or the like, a method using dyno mill, pearl mill, or the like. The average particle size before granulation is 0.01 to 3 μm, preferably 0.05 to 1 μm.

  Moreover, you may use organic substance, an inorganic solvent, inorganic salt, and various binders in the case of granulation. Examples of the binder used include magnesium chloride, aluminum sulfate, aluminum chloride, magnesium sulfate, alcohols, glycols and the like.

  The spherical particles obtained as described above preferably have a compression fracture strength of 0.2 MPa or more in order to suppress crushing and fine powder generation in the polymerization step. The particle size of the granulated ion-exchange layered silicate is in the range of 0.1 to 1000 μm, preferably 1 to 500 μm. There is no particular limitation on the pulverization method, and either dry pulverization or wet pulverization may be used.

  The ion-exchange layered silicate of the catalyst component (b) can be used as it is without any particular treatment, but it is desirable to perform the chemical treatment. The chemical treatment of the ion-exchange layered silicate refers to acids and salts. It means that an alkali, an organic substance or the like is brought into contact with an ion-exchange layered silicate.

  A common effect of chemical treatment is to exchange interlayer cations. In addition, various chemical treatments have the following various effects. For example, according to the acid treatment with acids, impurities on the silicate surface can be removed and the surface area can be increased by eluting cations such as Al, Fe, and Mg in the crystal structure. This contributes to increasing the acid strength of the silicate and increasing the amount of acid sites per unit weight.

  In alkali treatment with alkalis, the crystal structure of the clay mineral is destroyed, resulting in a change in the structure of the clay mineral.

  After carrying out the chemical treatment, it is possible to remove excess treatment agent and ions eluted by the treatment, which is preferable. At this time, generally, a liquid such as water or an organic solvent is used. After the dehydration, drying is performed. In general, the drying temperature can be 100 to 800 ° C, preferably 150 to 600 ° C. Exceeding 800 ° C. is not preferable because it may cause structural destruction of the silicate.

  Since these ion-exchange layered silicates have different characteristics depending on the drying temperature even if they are not structurally destroyed, it is preferable to change the drying temperature depending on the application. The drying time is usually 1 minute to 24 hours, preferably 5 minutes to 4 hours, and the atmosphere is preferably dry air, dry nitrogen, dry argon, or under reduced pressure. It does not specifically limit regarding a drying method, It can implement by various methods.

As the catalyst component (b) according to the present invention, the chemically-exchanged ion-exchange layered silicate has an Al / Si atomic ratio of 0.01 to 0.25, preferably 0.03 to 0.24. And more preferably in the range of 0.05 to 0.23. The Al / Si atomic ratio is considered to be an index of the acid treatment strength of the clay portion. Moreover, as a method of controlling the Al / Si atomic ratio within the above range, a method of performing chemical treatment using montmorillonite as the ion-exchange layered silicate before chemical treatment can be mentioned.
Aluminum and silicon in the ion-exchange layered silicate are measured by a method of preparing a calibration curve by a chemical analysis method by JIS method and quantifying with a fluorescent X-ray.

(3) Component (c):
The catalyst component (c) is an organoaluminum compound, and preferably an organoaluminum compound represented by the general formula: (AlR _n X _3-n ) _m is used. In formula, R represents a C1-C20 alkyl group, X represents a halogen, hydrogen, an alkoxy group, or an amino group, n represents 1-3, m represents the integer of 1-2, respectively. The organoaluminum compounds can be used alone or in combination.

  Specific examples of the organoaluminum compound include trimethylaluminum, triethylaluminum, trinormalpropylaluminum, trinormalbutylaluminum, triisobutylaluminum, trinormalhexylaluminum, trinormaloctylaluminum, trinormaldecylaluminum, diethylaluminum chloride, diethylaluminum. Examples thereof include sesquichloride, diethylaluminum hydride, diethylaluminum ethoxide, diethylaluminum dimethylamide, diisobutylaluminum hydride, and diisobutylaluminum chloride. Of these, trialkylaluminum and alkylaluminum hydride with m = 1 and n = 3 are preferable. More preferably, R is a trialkylaluminum having 1 to 8 carbon atoms.

(4) Catalyst adjustment:
The catalyst for olefin polymerization according to the present invention includes the component (a), the component (b) and the component (c). These may be contacted in the polymerization tank or outside the polymerization tank and preliminarily polymerized in the presence of olefin.
The olefin refers to a hydrocarbon having at least one carbon-carbon double bond, and examples thereof include ethylene, propylene, 1-butene, 1-hexene, 3-methylbutene-1, styrene, divinylbenzene, and the like. There is no restriction | limiting, You may use the mixture of these and another olefin. An olefin having 3 or more carbon atoms is preferable.

The amount of component (a), component (b) and component (c) used is arbitrary, but the ratio of the transition metal in component (b) to the aluminum in component (c) is the component (a). It is preferable to make it contact so that it may become 0.1-1000 (micromol): 0-100,000 (micromol) per 1g. In addition to the component (a), other types of complexes may be used for the purpose of more efficiently producing the propylene polymer (X) according to the present invention.
In this case, it is preferable to combine a metallocene compound capable of copolymerizing the terminal vinyl macromer produced by the catalyst component (a) and producing a high molecular weight polymer compared to the catalyst component (a).
As a particularly preferred metallocene compound, a catalyst component (a-2) represented by the following general formula (2) can be mentioned.

The compound represented by the general formula (2) is a metallocene compound, and in the general formula (2), Q ²¹ is a binding group that bridges two conjugated five-membered ring ligands, and has a carbon number. A divalent hydrocarbon group having 1 to 20 carbon atoms, a silylene group having a hydrocarbon group having 1 to 20 carbon atoms, or a germylene group having a hydrocarbon group having 1 to 20 carbon atoms, preferably a substituted silylene group or a substituted germylene group It is. The substituent bonded to silicon and germanium is preferably a hydrocarbon group having 1 to 12 carbon atoms, and two substituents may be linked. Specific examples include methylene, dimethylmethylene, ethylene-1,2-diyl, dimethylsilylene, diethylsilylene, diphenylsilylene, methylphenylsilylene, 9-silafluorene-9,9-diyl, dimethylsilylene, diethylsilylene, Examples thereof include diphenylsilylene, methylphenylsilylene, 9-silafluorene-9,9-diyl, dimethylgermylene, diethylgermylene, diphenylgermylene, methylphenylgermylene and the like.
Me is zirconium or hafnium, preferably hafnium.
Furthermore, X ²¹ and Y ²¹ are auxiliary ligands, and react with the cocatalyst of component [b] to generate an active metallocene having olefin polymerization ability. Therefore, as long as this purpose is achieved, X ²¹ and Y ²¹ are not limited to the type of ligand, and each independently represents hydrogen, a halogen group, a hydrocarbon group having 1 to 20 carbon atoms, An alkoxy group having 1 to 20 carbon atoms, an alkylamide group having 1 to 20 carbon atoms, a trifluoromethanesulfonic acid group, a phosphorus-containing hydrocarbon group having 1 to 20 carbon atoms or a silicon-containing hydrocarbon group having 1 to 20 carbon atoms is shown. .

In general formula (2), R ²¹ and R ²² are each independently a hydrocarbon group having 1 to 6 carbon atoms, preferably an alkyl group, more preferably an alkyl group having 1 to 4 carbon atoms. is there. Specific examples include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, n-pentyl, i-pentyl, n-hexyl, and preferably methyl. , Ethyl, n-propyl.
R ²³ and R ²⁴ each independently contains a halogen having 6 to 30 carbon atoms, preferably 6 to 24 carbon atoms, or a plurality of hetero elements selected from these. A good aryl group. Preferable examples include phenyl, 3-chlorophenyl, 4-chlorophenyl, 3-fluorophenyl, 4-fluorophenyl, 4-methylphenyl, 4-i-propylphenyl, 4-t-butylphenyl, 4-trimethylsilylphenyl, 4 -(2-fluorobiphenylyl), 4- (2-chlorobiphenylyl), 1-naphthyl, 2-naphthyl, 3,5-dimethyl-4-tert-butylphenyl, 3,5-dimethyl-4-trimethylsilylphenyl Etc.

Non-limiting examples of the metallocene compound include the following.
For example, dichloro {1,1′-dimethylsilylenebis (2-methyl-4-phenyl-4-hydroazulenyl)} hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-t-butylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylene Bis {2-methyl-4- (4-trimethylsilylphenyl) -4-hydroazulenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (3-chloro-4-t-butylphenyl) ) -4-Hydroazulenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- ( -Methyl-4-t-butylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (3-chloro-4-trimethylsilylphenyl) -4-hydroazurenyl} ] Hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (3-methyl-4-trimethylsilylphenyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2 -Methyl-4- (1-naphthyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (2-naphthyl) -4-hydroazurenyl}] hafnium, dichloro [ 1,1′-dimethylsilylenebis {2-methyl-4- (2-fluoro-4-biphenylyl) -4 -Hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (2-chloro-4-biphenylyl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-Methyl-4- (9-phenanthryl) -4-hydroazurenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chloro-2-naphthyl) -4-hydroazulenyl }] Hafnium, dichloro [1,1′-dimethylsilylenebis {2-ethyl-4- (4-chlorophenyl) -4-hydroazulenyl}] hafnium, dichloro [1,1′-dimethylsilylenebis {2-n-propyl -4- (3-Chloro-4-trimethylsilylphenyl) -4-hydroazurenyl}] hafnium, dic B [1,1′-dimethylsilylenebis {2-ethyl-4- (3-chloro-4-tert-butylphenyl) -4-hydroazulenyl}] hafnium, dichloro [1,1′-dimethylgermylenebis {2 -Methyl-4- (2-fluoro-4-biphenylyl) -4-hydroazulenyl}] hafnium, dichloro [1,1′-dimethylgermylenebis {2-methyl-4- (4-t-butylphenyl) -4 -Hydroazurenyl}] hafnium, dichloro [1,1 ′-(9-silafluorene-9,9-diyl) bis {2-ethyl-4- (4-chlorophenyl) -4-hydroazurenyl}] hafnium, and the like.

  In addition to the catalyst component (a), when other types of catalyst component (a-2) are used, the catalyst component (a-2) relative to the total amount of the catalyst component (a) and the catalyst component (a-2) is used. The ratio of the amount of) is arbitrary as long as it satisfies the characteristics of the propylene polymer (X), but is preferably 0.01 to 0.6. By changing this ratio, it is possible to adjust the balance between melt physical properties and catalyst activity, and particularly preferably for the production of propylene-based polymers for applications that require higher melt properties and high catalyst activity, It is 0.03-0.40, More preferably, it is the range of 0.07-0.2.

  The order in which the catalyst component (a), the component (b) and the component (c) are brought into contact with each other is arbitrary, and after contacting two of these components, the remaining one component may be brought into contact. Two components may be contacted simultaneously. In these contacts, a solvent may be used for sufficient contact. Examples of the solvent include aliphatic saturated hydrocarbons, aromatic hydrocarbons, aliphatic unsaturated hydrocarbons, halides thereof, and prepolymerized monomers. Specific examples of the aliphatic saturated hydrocarbon and the aromatic hydrocarbon include hexane, heptane, toluene and the like. Further, as a prepolymerized monomer, propylene can be used as a solvent.

[Prepolymerization]:
As described above, the catalyst according to the present invention is preferably subjected to a prepolymerization process comprising a small amount of polymerization by bringing an olefin into contact therewith. The olefin used is not particularly limited, but as described above, ethylene, propylene, 1-butene, 1-hexene, 1-octene, 4-methyl-1-pentene, 3-methyl-1-butene, vinylcyclohexane. Examples include alkanes and styrene. The olefin feed method may be any method such as a feed method for maintaining the olefin at a constant speed or in a constant pressure state, a combination thereof, or a stepwise change.
The prepolymerization temperature and time are not particularly limited, but are preferably in the range of −20 ° C. to 100 ° C. and 5 minutes to 24 hours, respectively. Further, the prepolymerization amount is preferably 0.01 to 100, more preferably 0.1 to 50, by weight ratio of the prepolymerized polymer to the component (b). Further, the component (c) can be added or added during the prepolymerization.
A method of coexisting a polymer such as polyethylene or polypropylene and a solid of an inorganic oxide such as silica or titania at the time of contacting or after the contact of the above components is also possible.
The catalyst may be dried after the prepolymerization. The drying method is not particularly limited, and examples thereof include reduced-pressure drying, heat drying, and drying by circulating a drying gas. These methods may be used alone or in combination of two or more methods. May be. In the drying step, the catalyst may be stirred, vibrated, fluidized, or allowed to stand.

[Detailed description of polymerization method]:
As the polymerization mode, any mode can be adopted as long as the olefin polymerization catalyst comprising the component (a), the component (b) and the component (c) and the monomer come into efficient contact. Specifically, a slurry method using an inert solvent, a bulk polymerization method using propylene as a solvent without substantially using an inert solvent, or a gas phase polymerization method for maintaining each monomer in a gaseous state without using a liquid solvent. Etc. can be adopted.
As the polymerization method, a method of performing continuous polymerization, batch polymerization, or prepolymerization is also applied.
Further, the number of polymerization stages is not particularly limited as long as the substance of the present invention can be produced. However, it is possible to employ a mode such as two stages of bulk polymerization, gas phase polymerization after bulk polymerization, and two stages of gas phase polymerization, and more. It is possible to produce with the number of polymerization stages.
However, in order to obtain the compound having the molecular weight and molecular weight distribution disclosed in the present invention, the first step is carried out by bulk polymerization and the second step is carried out by gas phase polymerization, or both the first step and the second step are carried out. It is preferable to carry out by phase polymerization.

[First step]:
In the case of slurry polymerization, a saturated aliphatic or aromatic hydrocarbon such as hexane, heptane, pentane, cyclohexane, benzene, toluene, or the like is used alone or as a polymerization solvent. The polymerization temperature is 0 to 150 ° C., and hydrogen can be used supplementarily as a molecular weight regulator. The polymerization pressure is suitably from 0 to 3 MPaG, preferably from 0 to 2 MPaG.
In the case of the bulk polymerization method, the polymerization temperature is 0 to 80 ° C, preferably 60 to 80 ° C, more preferably 65 to 75 ° C. The polymerization pressure is 0 to 5 MPaG, preferably 0 to 4 MPaG.
In the case of gas phase polymerization, the polymerization temperature is 0 to 200 ° C, preferably 60 to 120 ° C, and more preferably 70 to 100 ° C. The polymerization pressure is suitably from 0 to 4 MPaG, preferably from 0 to 3 MPaG.
Moreover, it is preferable not to use hydrogen as a molecular weight modifier in order to suppress chain transfer by hydrogen and increase the terminal vinyl content.

[Second step]:
In the case of gas phase polymerization, the polymerization temperature is 0 to 200 ° C, preferably 20 to 90 ° C, more preferably 30 to 80 ° C. In addition, hydrogen can be used as a molecular weight regulator. The polymerization pressure is suitably from 0 to 4 MPaG, preferably from 0 to 3 MPaG.

Here, the produced propylene-ethylene (or α-olefin) copolymer is partially copolymerized with a low vinyl terminal content, and both the main chain and the side chain are (non-crystalline) propylene-ethylene random copolymer. It is considered that a polymer having a branched structure having a polymer segment is formed. In this case, the lower the ethylene content in the amorphous propylene-ethylene random copolymer, the higher the vinyl terminal content. That is, by reducing the ethylene content in the amorphous propylene-ethylene random copolymer, it is possible to increase λmax of the CXS component of the propylene-based polymer (X) according to the present invention.
Therefore, in order to control the λmax of the CXS component to 2 or more, it is preferable that the ethylene content is 10 wt% to less than 40 wt%, in order to produce a polymer having a desired composition using ethylene as a comonomer. Therefore, it is necessary to control the ethylene gas composition in the gas phase to 10 mol% or more, preferably 15 mol% or more, and more preferably 20 mol% or more. The upper limit is 65 mol% or less, preferably 60 mol% or less, and more preferably 50 mol% or less.
Conversely, when the ethylene content is 40 wt% to 60 wt%, λmax of the CXS component becomes less than 2, and when ethylene is used as a comonomer, it is necessary to control the ethylene gas composition in the gas phase to 50 mol% or more. Preferably, it is 60 mol% or more, more preferably 65 mol% or more. Moreover, regarding an upper limit, it is 90 mol% or less, Preferably it is 87 mol% or less, More preferably, it is 85 mol% or less.

  The propylene-based polymer (X) according to the present invention thus obtained has (i) a weight average molecular weight (Mw) measured by GPC of 100,000 to 1,000,000, and (ii) a component insoluble in hot p-xylene. Is 0.3% or less, (iii) the strain hardening degree (λmax) in the measurement of elongational viscosity is 2.0 or more, and (iv) MFR (230 ° C., 2.16 kg load) is 0.1 to 20 g. / 10 minutes, and (v) a melt tension (MT) at 230 ° C. of 5 g or more, including a copolymer in which a crystalline segment is grafted to an amorphous segment as a side chain. In particular, such graft copolymers are present in the CXIS component (A). Polymerization mechanism in which the crystalline segment becomes a side chain and the non-crystalline segment becomes the main chain, in which the macromer of the crystalline component is produced in the first stage and copolymerized with the amorphous component in the second stage. From the point of view, it is natural.

2. Foaming agent The foaming agent used in the present invention is a thermal decomposition type chemical foaming agent or a volatile foaming agent, and any known one may be used.
Specific examples of the thermal decomposition type chemical blowing agent include sodium bicarbonate, ammonium carbonate, ammonium nitrite, azodicarbonamide, azobisformamide, isobutyronitrile, diazoaminobenzene and other azide compounds, N, N′-dinitroso Nitroso compounds such as pentatetramine and N, N′-dimethyl-dinitroterephthalamide are exemplified. In addition, this foaming agent may be used independently and may be used together 2 or more types.
Specific examples of the volatile foaming agent include alkane gas such as carbon dioxide, nitrogen, water and butane. In addition, this foaming agent may be used independently and may be used together with the above-mentioned thermal decomposition type chemical foaming agent.
In order to obtain a foam having uniform and fine foam cells and a high foaming ratio, it is preferable to use a volatile foaming agent.

  The blending amount of the blowing agent in the present invention is preferably in the range of 0.01 to 15.0 parts by weight, and in the range of 0.05 to 12.0 parts by weight with respect to 100 parts by weight of the propylene polymer (X). More preferred is 0.1 to 10.0 parts by weight. When the blending amount of the foaming agent is remarkably larger than 15.0 parts by weight, overfoaming occurs and it becomes difficult to make the foamed cells uniformly fine. Is not preferable because it is not performed.

3. Other compounding agents In addition to the propylene polymer (X) and the foaming agent, the resin composition for extrusion foam molding of the present invention includes known polymers, antioxidants, neutralizing agents, and the like, which are usually used for polyolefins. Various additives such as a light stabilizer, an ultraviolet absorber, an inorganic filler, an antiblocking agent, a lubricant, an antistatic agent, and a metal deactivator can be blended within a range that does not impair the object of the present invention.

  Examples of the polymer include propylene alone or a copolymer with other α-olefin, polymers such as low density polyethylene and high density polyethylene, and various thermoplastic elastomers.

Examples of antioxidants include phenolic antioxidants, phosphite antioxidants, and thio antioxidants, and examples of neutralizing agents include higher fatty acid salts such as calcium stearate and zinc stearate, Examples of the light stabilizer and the ultraviolet absorber include hindered amines, nickel complex compounds, benzotriazoles, and benzophenones.
Examples of inorganic fillers and antiblocking agents include calcium carbonate, silica, hydrotalcite, zeolite, aluminum silicate, magnesium silicate, and examples of lubricants include higher fatty acid amides such as stearic acid amide. it can.
Furthermore, examples of the antistatic agent include fatty acid partial esters such as glycerin fatty acid monoester, and examples of the metal deactivator include triazines, phosphones, epoxies, triazoles, hydrazides, and oxamides. it can.

II. Method for Preparing Extruded Foam Molding Resin Composition As a method for preparing the extrusion foam molding resin composition of the present invention, the propylene polymer (X) in the form of powder or pellets, a foaming agent, and others used as necessary The method of mixing these compounding agents with a dry blend, a Henschel mixer, etc. can be mentioned.
Further, depending on the situation, only the foaming agent may be separately fed during the production of the foam.

III. Foam The known foam can be used for the foam of the present invention. For example, the resin composition for extrusion foam molding of the present invention is introduced into an extruder using a normal extrusion apparatus equipped with a sizing and die of a desired shape. Usually, extrusion and foaming are performed at a cylinder temperature set at 130 to 170 ° C., a target shape is formed by a sizing device, and the target product can be easily obtained by a method of pulling the foam with a take-up device. it can.

  The foam of the present invention preferably has an average cell diameter of 400 μm or less, more preferably 300 μm or less, and even more preferably 200 μm or less. When the foamed cell diameter greatly exceeds 400 μm, poor appearance such as perforation occurs, and further, an excellent closed cell structure is not preferable.

  The foaming ratio of the foam of the present invention is preferably 5 times or more, more preferably 7 times or more, and further preferably 9 times or more. When the expansion ratio is less than 5 times, the expansion ratio is insufficient, and it is difficult to exhibit the buffering property, heat insulating property, sound absorbing property, and compression resistance of the obtained foam. On the other hand, if the expansion ratio greatly exceeds 40 times, it is difficult to make the foam cell diameter uniform and fine, and the resulting foam has poor appearance.

  The open cell ratio of the foam of the present invention is preferably 20% or less, more preferably 15% or less, and still more preferably 10% or less. When the open cell ratio exceeds 20%, even if it is a high-magnification foam, it is difficult to exhibit buffering properties, heat insulation properties, sound absorption properties, and compression resistance.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples. In Examples and Comparative Examples, various physical properties of the extrusion foam molding resin composition, the foam or its constituent components were measured and evaluated according to the following evaluation methods, and the following resins were used.

1. Evaluation method (1) Melt flow rate (MFR) [unit: g / 10 min]:
The propylene-based resin conforms to JIS K7210: 1999 “Method for testing plastics-thermoplastic melt mass flow rate (MFR) and melt volume flow rate (MVR)”, condition M (230 ° C., 2.16 kg load). Measured in conformity.
(2) Weight average molecular weight (Mw):
It was measured by the method described in the present specification by gel permeation chromatography (GPC).
(3) mm fraction:
The measurement was carried out by the method described in the present specification using GSX-400 and FT-NMR manufactured by JEOL. The unit is%.
(4) Elongation viscosity:
Using a rheometer, measurement was performed by the method described in the present specification.

(5) Melt tension (MT):
A cylinder heated at 230 ° C. is filled with 10 g of polymer using a Toyo Seiki Capillograph equipped with a cylinder with a diameter of 2 mmφ and a length of 40 mm, and a cylinder with a diameter of 10 mmφ and a length of 350 mm. After preheating for 5 minutes after filling, the polymer was sufficiently melted, and then the piston at the top of the cylinder was lowered at a speed of 20 mm / min to extrude the molten resin in the cylinder. The extruded resin passes through the orifice and is discharged to the outside. The extruded strand-shaped resin was wound up at a speed of 4 m / min, and the load at this time was defined as melt tension.

(6) Determination of ethylene content:
The average ethylene content in the copolymer was performed using an infrared spectrophotometer. The measurement conditions are shown below.
Equipment: Shimadzu FTIR-8300
Resolution: 4.0 cm ⁻¹
Measurement range: 4,000 to 400 cm ⁻¹
Sample adjustment: Polymer powder or pellets are adjusted to a film with a thickness of 500 μm with a heating and pressing press (temperature 190 ° C., pressurized to 100 MPa after 2 minutes of preheating)
Data processing:
(I) Using 760,700 cm ⁻¹ as a base point, calculate the absorbance peak area in that range (corresponding to ethylene content).
(Ii) Calculate the peak area / sample thickness.
(Iii) A calibration curve is prepared with a sample whose ethylene content has been quantified in advance by NMR, and the ethylene content is quantified by the formula [ethylene content∝peak area / sample thickness].

(7) Melting point (Tm):
Using a Seiko Instruments DSC6200, the sheet-shaped sample piece was packed in a 5 mg aluminum pan, heated from room temperature to 200 ° C. at a heating rate of 100 ° C./minute, held for 5 minutes, and then 10 ° C./minute. The crystallization temperature (Tc) is obtained as the maximum crystal peak temperature (° C.) when the temperature is lowered to 20 ° C., and then the maximum melting peak when the temperature is increased to 200 ° C. at 10 ° C./min. The melting point (Tm) was determined as the temperature (° C.).

(8) Average bubble diameter:
The strand-like foams obtained in each of Examples and Comparative Examples were cut vertically, and the cross section was photographed using a scanning electron microscope (manufactured by Keyence Corporation). Next, the foamed cell diameter in the cross section of the photographed foam was measured by a binarization processing software (NS method) manufactured by Nanosystem, and the average bubble diameter was calculated.
(9) Foaming ratio, open cell ratio:
After the strand-like foams obtained in each of the examples and comparative examples were cut vertically at intervals of 4 cm, they were filled into a cylindrical container having a height of 1.9 cm and a height of 4.5 cm without gaps. The foaming ratio and the open cell ratio were calculated by measuring the mass, volume and density of the foam and measuring the porosity by gas compression.

(10) Buffer property:
After the strand-like foams obtained in each of the Examples and Comparative Examples were cut vertically at intervals of 10 cm, 20 of them were placed side by side, and then a weight of 1 kg was placed thereon for 10 minutes, The foam was immediately removed, and the restored state of the foam at that time was visually observed, and the quality was judged according to the following criteria.
○: The original shape is immediately restored.
Δ: Restores slowly to the original shape.
X: The original shape is not restored.

2. Materials used (a) Propylene polymer (X)
The polymers (PP-1) to (PP-6) produced in the following Production Examples 1 to 6 and a commercially available polypropylene resin (PF814) were used.

[Production Example 1]
(1) [Synthesis of rac-dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4-phenyl-indenyl) hafnium dichloride]:
Synthesis of (1-a) dimethylbis (2- (2- (5-methyl) -furyl) -4-phenyl-indenyl) silane:
Synthesis was performed according to the method described in Example 1 of JP-A-2004-124044.

Synthesis of (1-b) rac-dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4-phenyl-indenyl) hafnium dichloride:
In a 100 ml glass reaction vessel, 5.3 g (8.8 mmol) of dimethylbis (2- (2- (5-methyl) -furyl) -4-phenyl-indenyl) silane and 150 ml of diethyl ether were added, and dry ice was added. -It cooled to -70 degreeC with the methanol bath. To this, 12 ml (18 mmol) of a 1.50 mol / liter n-butyllithium-hexane solution was added dropwise. After dropping, the temperature was returned to room temperature and stirred for 16 hours. The solvent of the reaction solution was concentrated under reduced pressure to about 20 ml, 200 ml of toluene was added, and the solution was cooled to −70 ° C. in a dry ice-methanol bath. Thereto was added 2.8 g (8.7 mmol) of hafnium tetrachloride. Thereafter, the mixture was stirred for 3 days while gradually returning to room temperature.
The solvent was distilled off under reduced pressure, recrystallized from dichloromethane / hexane, and racemic dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4-phenyl-indenyl) hafnium dichloride (purity 99% or more). ) Was obtained as yellow-orange crystals (2.9 g, yield 39%).
The resulting proton nuclear magnetic resonance method for racemate identified value according to ^{(1 H-NMR)} are shown below.
_{^{[1 H-NMR (CDCl 3}} ) Identification Results
Racemate: δ 1.12 (s, 6H), δ 2.42 (s, 6H), δ 6.06 (d, 2H), δ 6.24 (d, 2H), δ 6.78 (dd, 2H), δ 6. 97 (d, 2H), δ 6.96 (s, 2H), δ 7.25 to δ 7.64 (m, 12H).

(2) [Catalyst synthesis]:
(2-1) Chemical treatment of ion-exchangeable layered silicate 96% sulfuric acid (1044 g) was added to 3456 g of distilled water in a separable flask, and then montmorillonite (Menzawa Chemical Co., Ltd. Benclay SL: average particle size 19 μm) as a layered silicate. ) 600 g was added. The slurry was heated to 90 ° C. over 1 hour at 0.5 ° C./minute, and reacted at 90 ° C. for 120 minutes. The reaction slurry was cooled to room temperature in 1 hour, added with 2400 g of distilled water and then filtered to obtain 1230 g of a cake-like solid.
Next, 648 g of lithium sulfate and 1800 g of distilled water were added to the separable flask to make a lithium sulfate aqueous solution. The slurry was heated to 90 ° C. over 1 hour at 0.5 ° C./minute, and reacted at 90 ° C. for 120 minutes. The reaction slurry was cooled to room temperature in 1 hour, filtered after adding 1980 g of distilled water, further washed with distilled water to pH 3, and filtered to obtain 1150 g of cake-like solid.
The obtained solid was preliminarily dried at 130 ° C. for 2 days under a nitrogen stream, and then coarse particles of 53 μm or more were removed, and further, rotary kiln drying was performed under a condition of 215 ° C. under a nitrogen stream for a residence time of 10 minutes. 340 g was obtained.
The composition of this chemically treated smectite is Al: 7.81 wt%, Si: 36.63 wt%, Mg: 1.27 wt%, Fe: 1.82 wt%, Li: 0.20 wt%, Al / Si = 0.222 [mol / mol].

(2-2) Catalyst Preparation and Prepolymerization In a three-necked flask (volume: 1 L), 20 g of the chemically treated smectite obtained above was added, and heptane (114 mL) was added to form a slurry, to which triethylaluminum (50 mmol: 81 mL) of a heptane solution having a concentration of 71 mg / mL was added and stirred for 1 hour, then washed to 1/100 with heptane, and heptane was added so that the total volume became 200 mL.
In another flask (volume 200 mL), heptane (85 mL) was added to rac-dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4-phenyl-indenyl) hafnium dichloride (0.3 mmol). Then, triisobutylaluminum (0.6 mmol: 0.85 mL of a heptane solution with a concentration of 140 mg / mL) was added and stirred for 45 minutes at room temperature to cause a reaction. This solution was added to a 1 L flask containing chemically treated smectite and stirred at room temperature for 45 minutes. Thereafter, 214 mL of heptane was added, and this slurry was introduced into a 1 L autoclave.
After the internal temperature of the autoclave was set to 40 ° C., propylene was fed at a rate of 20 g / hour and prepolymerization was performed while maintaining the temperature at 40 ° C. for 2 hours. Thereafter, propylene feed was stopped, and residual polymerization was performed at 50 ° C. for 0.5 hour. After removing the supernatant of the resulting catalyst slurry by decantation, the prepolymerized catalyst was washed by adding decantation again with heptane. Triisobutylaluminum (12 mmol: 17 mL of a heptane solution having a concentration of 140 mg / mL) was added to the portion remaining after the decantation, and the mixture was stirred for 10 minutes. This solid was dried under reduced pressure for 2 hours to obtain 48.0 g of a dry prepolymerized catalyst. The prepolymerization ratio (value obtained by dividing the amount of prepolymerized polymer by the amount of solid catalyst) was 1.40.

(3) [Polymerization]
First step polymerization:
After sufficiently replacing the inside of the stirring autoclave having an internal volume of 200 liters with propylene, 45 kg of sufficiently dehydrated liquefied propylene was introduced. To this, 500 ml (0.12 mol) of a triisobutylaluminum / n-heptane solution was added, and the internal temperature was maintained at 30 ° C. Next, 8 g of the prepolymerized catalyst (with the weight reduced from the prepolymerized polymer) was injected with argon to start polymerization, and the temperature was raised to 70 ° C. over 32 minutes, and the polymerization temperature was maintained at 70 ° C. After 1 hour, unreacted propylene was purged and the inside of the autoclave was purged with nitrogen to stop the polymerization in the first step.

Second step polymerization:
To maintain the above nitrogen-substituted autoclave at 50 ° C. and atmospheric pressure, introduce 1.0 MPa in partial pressure of propylene and then 1.0 MPa in partial pressure of ethylene, and then maintain the gas composition of propylene and ethylene Propylene and ethylene were supplied at a ratio of 81 mol% and 19 mol%, respectively, and the conditions of 50 ° C. and a total pressure of 2.0 MPa were maintained. The average gas composition of the polymerization in the second step was C2: 54.1%. Two hours later, 100 ml of ethanol was introduced to stop the reaction. Unreacted ethylene / propylene mixed gas was purged to obtain 11.3 kg of polymer (PP-1).

[Production Example 2]
(1) [Polymerization]:
First step polymerization:
The same polymerization as in the first step of Production Example 1 was carried out except that 9.5 g of the prepolymerized catalyst (with a weight obtained by subtracting the prepolymerized polymer) was used.

Second step polymerization:
To maintain the nitrogen-substituted autoclave at 50 ° C. and atmospheric pressure, introduce 0.5 MPa in partial pressure of propylene and then 1.5 MPa in partial pressure of ethylene, and then maintain the gas composition of propylene and ethylene Propylene and ethylene were supplied at a ratio of 58 mol% and 42 mol%, respectively, and the conditions of 50 ° C. and a total pressure of 2.0 MPa were maintained. The average gas composition of the polymerization in the second step was C2: 72.9%. Two hours later, 100 ml of ethanol was introduced to stop the reaction. The unreacted ethylene / propylene mixed gas was purged to obtain 9.7 kg of a polymer (PP-2).

[Production Example 3]
(1) [Synthesis of rac-dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4-phenyl-indenyl) zirconium dichloride]:
Synthesis was performed according to the method described in JP-A-2004-2259.

(2) [Catalyst synthesis]:
In a three-necked flask (volume: 1 L), 20 g of silica-supported MAO (product name: MAO-S manufactured by WITCO) was added, and heptane (200 mL) was added to prepare a slurry.
In another flask (volume 200 mL), heptane (85 mL) was added to rac-dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4-phenyl-indenyl) zirconium dichloride (0.3 mmol). Then, triisobutylaluminum (0.6 mmol: 0.85 mL of a heptane solution having a concentration of 140 mg / mL) was added and stirred for 30 minutes at room temperature to react. This solution was added to a 3 L flask containing silica-supported MAO and stirred at room temperature for 30 minutes. Thereafter, 215 mL of heptane was added, and this slurry was introduced into a 1 L autoclave.
After setting the internal temperature of the autoclave to 40 ° C., propylene was fed at a rate of 20 g / hour, and prepolymerization was performed while maintaining the temperature at 40 ° C. for 2 hours. Thereafter, propylene feed was stopped and residual polymerization was carried out for 0.5 hour. After removing the supernatant of the resulting catalyst slurry by decantation, triisobutylaluminum (12 mmol: 17 mL of a heptane solution having a concentration of 140 mg / mL) was added and stirred for 10 minutes. This solid was dried under reduced pressure for 2 hours to obtain 55.9 g of a dry prepolymerized catalyst. The prepolymerization ratio (value obtained by dividing the amount of prepolymerized polymer by the amount of solid catalyst) was 1.80.

(3) [Polymerization]:
First step polymerization:
After sufficiently replacing the inside of the stirring autoclave having an internal volume of 200 liters with propylene, 45 kg of sufficiently dehydrated liquefied propylene was introduced. To this was added 10 liters of hydrogen (as a standard volume) and 500 ml (0.12 mol) of a triisobutylaluminum / n-heptane solution, and the internal temperature was maintained at 30 ° C. Next, 8 g of the prepolymerized catalyst (with a weight obtained by subtracting the prepolymerized polymer) was injected with argon to start the polymerization, the temperature was raised to 70 ° C. over 30 minutes, and the polymerization temperature was maintained at 70 ° C. After 1 hour, unreacted propylene was purged and the inside of the autoclave was purged with nitrogen to stop the polymerization in the first step.

Second step polymerization:
To maintain the above nitrogen-substituted autoclave at 50 ° C. and atmospheric pressure, introduce propylene into a partial pressure of 0.3 MPa, then introduce ethylene into a partial pressure of 1.2 MPa, and then maintain the gas composition of propylene and ethylene Propylene and ethylene were supplied at a ratio of 36 mol% and 64 mol%, respectively, and the conditions of 50 ° C. and a total pressure of 1.5 MPa were maintained. The average gas composition of the polymerization in the second step was C2: 80.3%. After 3.5 hours, 100 ml of ethanol was introduced to stop the reaction. The unreacted ethylene / propylene mixed gas was purged to obtain 11.6 kg of a polymer (PP-3).

[Production Example 4]
(1) [Polymerization]
First step polymerization:
After sufficiently replacing the inside of the stirring autoclave having an internal volume of 200 liters with propylene, 45 kg of sufficiently dehydrated liquefied propylene was introduced. To this, 500 ml (0.12 mol) of a triisobutylaluminum / n-heptane solution was added, and the internal temperature was maintained at 30 ° C. Next, 10 g of the prepolymerized catalyst synthesized in Production Example 1 (with a weight obtained by subtracting the prepolymerized polymer) was injected with argon to start the polymerization, the temperature was raised to 75 ° C. over 30 minutes, and the polymerization temperature was raised to 75 ° C. Maintained. After 1 hour, unreacted propylene was purged and the inside of the autoclave was purged with nitrogen to stop the polymerization in the first step.

Second step polymerization:
To maintain the above nitrogen-substituted autoclave at 70 ° C. and atmospheric pressure, introduce propylene in a partial pressure of 0.5 MPa, then ethylene in a partial pressure of 1.5 MPa, and then maintain the gas composition of propylene and ethylene Propylene and ethylene were supplied at a ratio of 34 mol% and 66 mol%, respectively, and the conditions of 70 ° C. and a total pressure of 2.0 MPa were maintained. The average gas composition of the polymerization in the second step was C2: 80.1%. After 50 minutes, 100 ml of ethanol was introduced to stop the reaction. Unreacted ethylene / propylene mixed gas was purged to obtain 9.0 kg of a polymer (PP-4).

[Production Example 5]
(1) [Synthesis of rac- (1,1′-dimethylsilylenebis (2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl)) hafnium dichloride]:
The synthesis of rac- (1,1′-dimethylsilylenebis (2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl)) hafnium dichloride was carried out in the same manner as in Example 1 of JP-A-11-240909. did.

(2) [Catalyst synthesis]:
Into a three-necked flask (volume: 1 L), 10 g of the chemically treated smectite obtained in Production Example 1 is added, and heptane (66 mL) is added to form a slurry. 34 mL) was added, and the mixture was stirred for 1 hour, washed with heptane to 1/1000, and heptane was added so that the total volume became 100 mL.
In another flask (volume: 200 mL), rac-dimethylsilylenebis (2- (2- (5-methyl) -furyl) -4-phenyl-indenyl) hafnium dichloride (0. 135 mmol) was dissolved in toluene (38 mL) (complex solution 1).
In another flask (volume 200 mL), rac- (1,1′-dimethylsilylenebis (2-methyl-4- (4-chlorophenyl) -4-hydroazurenyl)) hafnium dichloride (0. 015 mmol) was dissolved in toluene (5 mL) (complex solution 2).
To a 3 L flask containing chemically treated smectite, triisobutylaluminum (0.6 mmol: 0.85 mL of a heptane solution having a concentration of 140 mg / mL) was added, and the complex solution 1 was added, followed by addition of the complex solution 2. Stir at room temperature for 60 minutes. Thereafter, 356 mL of heptane was added, and this slurry was introduced into a 1 L autoclave.
After setting the internal temperature of the autoclave to 40 ° C., propylene was fed at a rate of 10 g / hour, and prepolymerization was performed while maintaining 40 ° C. for 2 hours. Thereafter, propylene feed was stopped, and residual polymerization was performed at 50 ° C. for 0.5 hour. After removing the supernatant of the obtained catalyst slurry by decantation, triisobutylaluminum (12 mmol: 8.5 mL of a heptane solution having a concentration of 140 mg / mL) was added and stirred for 10 minutes. This solid was dried under reduced pressure for 2 hours to obtain 27.5 g of a dry prepolymerized catalyst. The prepolymerization ratio (value obtained by dividing the amount of prepolymerized polymer by the amount of solid catalyst) was 1.75.

(3) [Polymerization]
First step polymerization:
After sufficiently replacing the inside of the stirring autoclave having an internal volume of 200 liters with propylene, 45 kg of sufficiently dehydrated liquefied propylene was introduced. To this, 500 ml (0.12 mol) of a triisobutylaluminum / n-heptane solution was added, and the internal temperature was maintained at 30 ° C. Next, 6 g of the prepolymerized catalyst (with a weight obtained by subtracting the prepolymerized polymer) was injected with argon to start the polymerization, the temperature was raised to 75 ° C. over 35 minutes, and the polymerization temperature was maintained at 75 ° C. After 1 hour, unreacted propylene was purged and the inside of the autoclave was purged with nitrogen to stop the polymerization in the first step.

Second step polymerization:
To maintain the above nitrogen-substituted autoclave at 50 ° C. and atmospheric pressure, introduce propylene with a partial pressure of 0.7 MPa, then ethylene with a partial pressure of 1.3 MPa, and then maintain the gas composition of propylene and ethylene Propylene and ethylene were supplied at a ratio of 67 mol% and 33 mol%, respectively, and the conditions of 50 ° C. and a total pressure of 2.0 MPa were maintained. The average gas composition of the polymerization in the second step was C2: 65.1%. After 1 hour, 100 ml of ethanol was introduced to stop the reaction. The unreacted ethylene / propylene mixed gas was purged to obtain 9.8 kg of a polymer (PP-5).

[Production Example 6]
(1) [Polymerization]:
First step polymerization:
The same polymerization as in the first step of Production Example 5 was performed.

Second step polymerization:
To maintain the above nitrogen-substituted autoclave at 55 ° C. and atmospheric pressure, introduce propylene in a partial pressure of 0.58 MPa, then ethylene in a partial pressure of 1.42 MPa, and then maintain the gas composition of propylene and ethylene Propylene and ethylene were supplied at a ratio of 57 mol% and 43 mol%, respectively, and the conditions of 55 ° C. and a total pressure of 2.0 MPa were maintained. The average gas composition of the polymerization in the second step was C2: 70.8%. Two hours later, 100 ml of ethanol was introduced to stop the reaction. Unreacted ethylene / propylene mixed gas was purged to obtain 10.3 kg of polymer (PP-6).

(Commercial item)
PF814 (electron beam irradiated product):
A high melt tension polypropylene (MFR = 2.5 g / 10 min, melting point 159.4 ° C.) manufactured by Basel was used.

(B) Foaming agent:
As a foaming agent, a product name: CF40E manufactured by Nippon Boehringer Ingelheim, which is a baking soda-based foaming agent, was used.

[Example 1]
Tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4), which is a phenolic antioxidant, with respect to 100 parts by weight of the polymer (PP-1) obtained in Production Example 1. '-Hydroxyphenyl) propionate] methane (trade name: IRGANOX 1010, manufactured by Ciba Specialty Chemicals) 0.05 part by weight, tris (2,4-di-t-butylphenyl) which is a phosphite antioxidant Phosphite (trade name: IRGAFOS 168, manufactured by Ciba Specialty Chemicals Co., Ltd.) 0.05 parts by weight, and calcium stearate as a neutralizer (trade name: calcium stearate, manufactured by Nippon Oil & Fats Co., Ltd.) 0.05 After blending parts by weight and mixing with a high-speed stirring mixer (Henschel mixer, trade name) for 3 minutes at room temperature, the mixture is melt-kneaded with an extruder and then mixed with pellets. Got.

In order to obtain a foam using an extruder with a screw diameter of 30 mm, 100 parts by weight of the pellets and 10 parts by weight of an inorganic (bicarbonate) foaming agent (trade name: CF40E, manufactured by Nippon Boehringer Ingelheim Co., Ltd.) were added. The strand-like foam was heated and melt-plasticized at a resin temperature of 200 ° C., and continuously taken out while cooling and solidifying the strand-like foam extruded from the strand die to obtain a strand-like foam. The evaluation results of the obtained foam are shown in Table 1.
The foam satisfying the constitution of the present invention had a high magnification, a low open cell ratio, an excellent buffering property, and a dense average cell diameter.

[Example 2]
It implemented like Example 1 except having used polymer (PP-2) instead of polymer (PP-1), and an evaluation result is shown in Table 1.
The foam satisfying the constitution of the present invention had a high magnification, a low open cell ratio, an excellent buffering property, and a dense average cell diameter.

[Example 3]
It implemented similarly to Example 1 except having used polymer (PP-5) instead of polymer (PP-1), and an evaluation result is shown in Table 1.
The foam satisfying the constitution of the present invention had a high magnification, a low open cell ratio, an excellent buffering property, and a dense average cell diameter.

[Example 4]
It implemented like Example 1 except having used polymer (PP-6) instead of polymer (PP-1), and an evaluation result is shown in Table 1.
The foam satisfying the constitution of the present invention had a high magnification, a low open cell ratio, an excellent buffering property, and a dense average cell diameter.

[Comparative Example 1]
In the same manner as in Example 1 except that a propylene resin (PF814) different from the propylene polymer (X) specified in the present invention was used instead of the polymer (PP-1), strand-like foaming was performed. Got the body.
Although the foam which does not satisfy | fill the structure of this invention is high magnification, since the open cell ratio is high and the bubble diameter is also non-uniform | heterogenous, it is inferior to buffering property. The evaluation results of the foam are shown in Table 1.

[Comparative Example 2]
In the same manner as in Example 1 except that a polymer (PP-3) different from the propylene polymer (X) specified in the present invention was used instead of the polymer (PP-1), a strand shape was obtained. A foam was obtained.
A foam that does not satisfy the constitution of the present invention has a low magnification, a high open cell ratio, and a large average cell diameter, and therefore has poor buffering properties. Table 1 shows the evaluator results of the foam.

[Comparative Example 3]
In the same manner as in Example 1 except that a polymer (PP-4) different from the propylene-based polymer (X) specified in the present invention was used instead of the polymer (PP-1), a strand shape was obtained. A foam was obtained.
A foam that does not satisfy the constitution of the present invention has a low magnification, a high open cell ratio, and a large average cell diameter, and therefore has poor buffering properties. Table 1 shows the evaluator results of the foam.

  The resin composition for extrusion foam molding of the present invention is highly crystalline, has a slow crystallization rate, good melt flow characteristics, high melt tension, and high strain curability. Even with the expansion ratio, it is suitable for obtaining a highly closed cell structure having uniform and fine foam cells. And the foam obtained by extrusion foam molding using it is more excellent in compression characteristics, buffer properties, heat insulation, appearance, cleanliness, recyclability, impact resistance and odor resistance. It can be suitably used for food containers, automobile interior materials, packed products, etc., and has high industrial applicability.

It is a figure of the description of the baseline of a chromatogram in GPC, and a section. It is a plot figure which shows an example of the extensional viscosity measured with the uniaxial extensional viscometer. It is a figure which shows an example of the TEM observation result of the propylene polymer (X) which concerns on this invention. It is a figure which shows an example of the TEM observation result of the propylene polymer (X) which concerns on this invention. It is a figure which shows an example of the TEM observation result of a normal propylene polymer.

Claims (9)

It is composed of the following component (A) that is insoluble in p-xylene at 25 ° C. and component (B) that is soluble in p-xylene at 25 ° C., and (i) a weight average molecular weight (Mw) measured by GPC is 10 (Ii) a component insoluble in hot p-xylene is 0.3% by weight or less, (iii) a strain hardening degree (λmax) in the measurement of elongational viscosity is 2.0 or more, (Iv) Propylene-based weight in which MFR (230 ° C., 2.16 kg load) is 0.1 to 20 g / 10 min, and (v) melt tension (MT) at 230 ° C. measured by a melt tension tester is 5 g or more. A resin composition for extrusion foam molding, comprising a combination (X) and a foaming agent.
Component (A): Component (CXIS) that is insoluble in p-xylene at 25 ° C. having the requirements defined in the following (A1) to (A5).
(A1) It is 20 to 95 weight% with respect to the polymer (X) whole quantity.
(A2) The weight average molecular weight (Mw) measured by GPC is 100,000 to 1,000,000.
(A3) The isotactic triad fraction (mm) measured by ¹³ C-NMR is 93% or more.
(A4) The strain hardening degree (λmax) in the measurement of elongational viscosity is 2.0 or more.
(A5) A propylene unit and an ethylene unit or an α-olefin unit are contained.
Component (B): Component (CXS) that dissolves in p-xylene at 25 ° C. having the requirements defined in the following (B1) to (B3).
(B1) 5 to 80% by weight based on the total amount of the polymer (X).
(B2) The weight average molecular weight (Mw) measured by GPC is 100,000 to 1,000,000.
(B3) Contains propylene units, ethylene units and / or α-olefin units.   The component (B) of the propylene-based polymer (X) further has a requirement that (B4) the strain hardening degree (λmax) in the measurement of elongational viscosity is 2.0 or more. The resin composition for extrusion foam molding as described in 2.   The propylene polymer (X) is composed of a polymer having a branched structure having a crystalline propylene polymer segment as a side chain and an amorphous propylene copolymer segment as a main chain. The resin composition for extrusion foam molding as described in 2.   Component (A) of the propylene polymer (X) is composed of a polymer having a branched structure in which a crystalline propylene polymer segment is a side chain and an amorphous propylene copolymer segment is a main chain. The resin composition for extrusion foam molding according to claim 1.   The component (A) of the propylene-based polymer (X) contains an ethylene unit and has an ethylene content of 0.1 to 10% by weight, for extrusion foam molding according to claim 1. Resin composition.   The resin composition for extrusion foam molding according to claim 1, wherein the component (B) of the propylene-based polymer (X) contains an ethylene unit and has an ethylene content of 10 to 60% by weight. object.   A foam comprising the resin composition for extrusion foam molding according to any one of claims 1 to 6 obtained by extrusion molding.   The foam according to claim 7, wherein the foaming ratio is 5 to 40 times, and the open cell ratio is 20% or less.   The foam according to claim 7 or 8, wherein an average cell diameter is 400 µm or less.

Images