JP2000186175A - Propylene-based polymer or polymer composition for biaxially oriented blow molding and vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a propylene-based polymer or polymer composition for biaxially oriented blow molding having good impact resistance and transparency and excellent in uniform stretchability and provide a biaxially oriented blow molded vessel. SOLUTION: This propylene-based polymer or polymer composition for biaxially oriented blow molding comprises a propylene-based polymer obtained by polymerizing a monomer consisting essentially of propylene at first stage to produce a crystalline propylene-based polymer component (a) having >=5 d1/g intrinsic viscosity and polymerizing a monomer consisting essentially of propylene at second or more stages to continuously produce a crystalline propylene-based polymer component (b) having <3 dl/g intrinsic viscosity, in which a ratio of the component (a) in the propylene-based polymer is >=0.05 wt.% and <25 wt.% and intrinsic viscosity of whole propylene-based polymer is <3 dl/g and Mw/Mn is <10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a propylene-based polymer or polymer composition for biaxial stretch blow molding, and a biaxially stretch blow molded container.

[0002]

2. Description of the Related Art Polypropylene is widely used in the fields of films, sheets, containers and the like because of its excellent heat resistance and rigidity. In particular, in the field of containers, a vacuum forming method, a press forming method, or an extrusion blow molding method in which air is blown into a parison extruded in a tube shape is used in a secondary process after a sheet is formed.

In recent years, a biaxial stretch blow molding method in which air is blown after injection molding has been favorably used from the viewpoint of improving the properties of a bottle and a molding cycle. This molding method is performed by the same machine after injection molding of a preform. It is roughly classified into a one-stage method in which stretch blow molding is performed, and a two-stage method in which a preform is obtained by injection molding and then heated again to stretch blow molding.

In order to improve the physical properties and moldability of polypropylene bottles, for example, Japanese Patent Publication No.
Stretching obtained by preform molding by injection molding, preliminary blowing, and stretch blow molding using a propylene-ethylene random copolymer having an ethylene content of 1 to 6% by weight and a melt flow rate of 4 to 50 g / 10 minutes. A blow container is disclosed.

Japanese Patent Application Laid-Open No. 9-24538 discloses that
A container formed by stretch blow molding polypropylene having a melt flow rate of 5 to 80 g / 10 minutes is disclosed.

JP-A-10-58528 discloses 100 parts by weight of a propylene / ethylene random copolymer having an ethylene content of 2 to 6% by weight and a melt flow rate of 10 to 50 g / 10 min. 03-2
A cold parison blow molded container composed of parts by weight is disclosed.

[0007]

Problems to be Solved by the Invention
The container described in JP-A No. 27 is not always sufficient in transparency and also not sufficient in uniform stretchability. Also, JP-A-9-24538 and JP-A-10-58
The container described in Japanese Patent No. 528 is excellent in transparency, but is insufficient in uniform stretchability.

An object of the present invention is to provide a propylene-based polymer or polymer composition for biaxial stretch blow molding having good impact resistance and transparency and excellent uniform stretchability, and a biaxial stretch blow molded container. Is to provide.

[0009]

Means for Solving the Problems The inventors of the present invention have studied to solve the disadvantages of the conventional polymer composition, and as a result, have found that a specific propylene-based polymer produced in the first and second stages and subsequent stages is produced. It has been found that the combination or the polymer composition thereof achieves the object of the present invention, and the present invention has been completed.

That is, in the present invention, in the first step, a monomer having propylene as a main component is polymerized to have an intrinsic viscosity of 5 dl.
/ G or more of the crystalline propylene polymer component (a) is produced, and a monomer having propylene as a main component is polymerized in the second and subsequent steps to form a crystalline propylene polymer component having an intrinsic viscosity of less than 3 dl / g ( a propylene polymer obtained by continuously producing b), wherein the proportion of the component (a) in the propylene polymer is 0.05% by weight or more and less than 25% by weight; Has an intrinsic viscosity of 3 dl / g
Propylene polymer (A) having a Mw / Mn of less than 10 and a propylene polymer for biaxial stretch blow molding. Further, the present invention is characterized by comprising a polymer composition containing 1 to 99 parts by weight of the propylene-based polymer (A) and 99 to 1 part by weight of the following propylene-based copolymer (B) 2. It is a propylene polymer composition for axial stretch blow molding. (B): The content of the repeating unit derived from propylene is 98 to 60% by weight, the content of the repeating unit derived from ethylene is 0 to 15% by weight, and the content of the repeating unit derived from 1-butene is 0 to 0%. Propylene copolymer comprising 25% by weight Further, the present invention relates to 100 parts by weight of the above-mentioned propylene-based polymer or propylene-based polymer composition,
A propylene-based polymer composition for biaxial stretch blow molding, further comprising a polymer composition containing 0.5 part by weight or less of a crystal nucleating agent. The present invention also provides a biaxially stretch blow-molded container comprising the above-mentioned propylene-based polymer or propylene-based polymer composition. Hereinafter, the present invention will be described in detail. In addition, in the text, the “component (a)” simply refers to the crystalline propylene-based polymer component (a), and the “component (b)” simply refers to the crystalline propylene-based polymer component (b).

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The propylene polymer (A) used in the present invention is composed of a component (a) and a component (b). Here, the component (a) is preferably an isotactic propylene-based polymer. Among them, a homopolymer of propylene or propylene, ethylene and an α-olefin having 4 to 12 carbon atoms to such an extent that crystallinity is not lost. And the like are particularly preferred. Examples of the α-olefin include 1-butene, 4-methylpentene-1, 1-octene, 1-hexene and the like. Copolymerization is performed for the purpose of controlling flexibility and transparency, and the content of monomers other than propylene is preferably 10% by weight or less for ethylene and 30% by weight or less for the α-olefin. Among them, homopolymers of propylene, random copolymers of propylene with 10% by weight or less of ethylene, propylene and 30% by weight or less of α having 4 to 12 carbon atoms
A crystalline propylene copolymer selected from a random copolymer with olefin or a tertiary random copolymer with propylene and 10% by weight or less of ethylene and 30% by weight or less of α-olefin having 4 to 12 carbon atoms. The polymer component is more preferably used, and a more preferred α-olefin is 1
-Butenes. Particularly preferred component (a) for flexibility and transparency is ethylene in an amount of 1% by weight or more and 10% by weight or more.
It is a copolymer containing not more than% by weight.

The intrinsic viscosity of component (a) must be at least 5 dl / g. It is preferably at least 6 dl / g, more preferably at least 7 dl / g. If it is less than 5 dl / g, the propylene-based polymer is inferior in uniform stretchability, and the object of the present invention cannot be achieved.

The proportion of the component (a) in the whole propylene polymer must be 0.05% by weight or more and less than 25% by weight. Preferably it is at least 0.3% by weight and less than 20% by weight. If it is less than 0.05% by weight, uniform stretchability is poor. When the amount of the component (a) is 25% by weight or more, the fluidity is remarkably reduced, so that the object of the present invention cannot be achieved.

From the viewpoint of uniform stretching, the amount of the component (a) preferably satisfies the following (formula 1). When the amount of the component (a) satisfies the expression (1), the effect of improving the uniform stretchability is large. Here, EXP (X) represents e ^X , where e is the base of the natural logarithm. (Formula 1) Ratio of component (a) (% by weight) ≧ 400 × EXP (−0.6 × Intrinsic viscosity (dl / g) of component (a)) In particular, when emphasis is placed on fluidity, uniform stretchability is obtained. It is preferable that the amount of the component (a) is small as long as the requirements (for example, (formula 1) can be satisfied) are satisfied.

The component (b) in the present invention comprises the component (a)
It must be a propylene-based polymer obtained by continuous production after the production of. That is, component (a) is produced by polymerizing a monomer mainly composed of propylene in the presence of a stereoregular olefin polymerization catalyst represented by a Ziegler-Natta catalyst, and then propylene is produced in the presence of the catalyst and the polymer. It is necessary to produce the component (b) by polymerizing a monomer as a main component, and only the intrinsic viscosity is 5d.
1 / g or more of crystalline propylene polymer and intrinsic viscosity of 3
A blend of a propylene-based polymer of less than dl / g does not produce or is insufficiently effective in improving uniform stretchability.

A specific method for producing a polymer is a batch polymerization method in which the component (a) is polymerized in the same polymerization tank and then the component (b) is polymerized, or a polymerization comprising at least two tanks. Tanks are arranged in series, and after polymerization of component (a), the product is transferred to the next polymerization tank, and then the polymerization of component (b) is performed in the polymerization tank.

The intrinsic viscosity of component (b) must be less than 3 dl / g. Preferably it is less than 2 dl / g.
If it is 3 dl / g or more, the intrinsic viscosity of the whole polymer becomes too large, so that the fluidity is poor and there is a problem in processing. Even if the viscosity of the entire system is adjusted by adding other components, there is a problem in miscibility and the like. The intrinsic viscosity [η] b of the component (b) is a value calculated from the following equation. [η] b = ([η] T × 100− [η] a × Wa) / Wb [η] T: intrinsic viscosity of the entire crystalline propylene polymer [η] a: intrinsic viscosity of component (a) Wa : Ratio of component (a) (% by weight) Wb: Ratio of component (b) (% by weight)

As the component (b), an isotactic propylene polymer satisfying the above conditions is preferably used.
Among them, propylene homopolymer, propylene and ethylene,
A crystalline copolymer with an α-olefin or the like, a polymer in which an amorphous ethylene / α-olefin copolymer is dispersed in a crystalline propylene polymer, and the like are particularly preferable. Particularly preferred component (b) is a propylene homopolymer,
Random copolymer of propylene and 10% by weight or less of ethylene, propylene and 30% by weight or less of 4 to 12 carbon atoms
Or a tertiary random copolymer of propylene, 10% by weight or less of ethylene, and 30% by weight or less of an α-olefin having 4 to 12 carbon atoms. If the amount of the monomer other than propylene exceeds this range, most of the crystallinity is lost, and the value as a product may be lost. More preferred α-olefins include, for example, 1-butene.

The propylene polymer (A) used in the present invention
The overall intrinsic viscosity must be less than 3 dl / g. When the intrinsic viscosity is 3 dl / g or more, the fluidity of the entire system is poor and there is a problem in processing. Preferably 1 dl / g or more and less than 3 dl / g, more preferably 1 dl / g or more and 2 d
less than 1 / g.

The propylene polymer (A) used in the present invention
Requires that Mw / Mn be less than 10. Mw / M
If n is 10 or more, the appearance of the molded article may be poor or the elongation property may be lost. Preferably it is 4 or more and less than 8.

The propylene polymer (A) used in the present invention
Can be obtained using a stereoregular olefin polymerization catalyst system. Preferably, for example, a catalyst system containing Ti, Mg, and halogen as essential components is used. More preferably, the component (a) is obtained by employing a catalyst system and a production condition that give a polymerization activity of 1 g of the catalyst at the time of monomer polymerization and 2000 g or more per hour. Here, "1 g of catalyst" refers to 1 g of a solid catalyst containing Ti, Mg, and halogen as essential components.

Regarding the catalyst system, see, for example,
Those mentioned in JP-A-216017 can be suitably used. Specifically, (a) an organosilicon compound having a Si—O bond (preferable is a compound represented by the general formula Si (OR
¹⁾ _m (R ²⁾ is an alkoxysilane compound represented by the _4-m. In the formula, R ¹ and R ² represent a hydrocarbon group having 1 to 20 carbon atoms. Further, m is preferably 1 ≦ m ≦ 4, and particularly preferably a tetraalkoxysilane compound where m = 4. ) And ester compounds (mono- and polyvalent carboxylic esters are used, and olefin carboxylic esters such as methacrylic acid esters and maleic acid esters, and phthalic acid esters are preferable, and diesters of phthalic acid are particularly preferable). General formula Ti (OR ³ ) _a X
_4-a (wherein, R ³ is a hydrocarbon group having 1 to 20 carbon atoms, X is a halogen atom, a is a number of 0 <a ≦ 4, preferably 2 ≦ a ≦ 4, particularly preferably a = 4) was reduced with an organomagnesium compound (in particular, a Grignard compound, a dialkylmagnesium compound, or a diarylmagnesium compound is preferably used), and the resulting solid product was treated with an ester compound. Thereafter, the mixture is treated with a mixture of an ether compound (a dialkyl ether is used, particularly preferably dibutyl ether and diisoamyl ether is preferably used) and titanium tetrachloride or a mixture of an ether compound, titanium tetrachloride and an ester compound to obtain a triacetate. (B) organoaluminum compound (triethylaluminum) Arm, triisobutylaluminum,
A mixture of triethylaluminum and diethylaluminum chloride and tetraethyldialumoxane are preferably used), (c) an electron donating compound (ter
t-butyl-n-propyldimethoxysilane, tert
-Butylethyldimethoxysilane, dicyclopentyldimethoxysilane and the like are preferably used).

The propylene polymer (A) used in the present invention
As the production conditions, the molar ratio of (b) Al atoms in the organoaluminum compound / (a) Ti atoms in the solid catalyst is usually 1 to 2000, preferably 5 to 1500,
Conditions are used such that the molar ratio of (c) the electron-donating compound / (b) the Al atom in the organoaluminum compound is usually from 0.02 to 500, preferably from 0.05 to 50.

The method for producing the polymer of the component (a) includes a solvent polymerization method using an inert solvent represented by a hydrocarbon such as hexane, heptane, octane, decane, cyclohexane, methylcyclohexane, benzene, toluene and xylene; A bulk polymerization method using a liquid monomer as a solvent and a gas phase polymerization method performed in a gaseous monomer can be used. Among these, bulk polymerization and gas phase polymerization are preferred because of easy post-treatment.

The polymerization temperature of the component (a) is usually from 20 to 150.
C., preferably in the range from 35 to 95.degree. Polymerization in this temperature range is preferable from the viewpoint of productivity, and is also preferable in obtaining a desired ratio of the components (a) and (b).

The polymerization rate during the polymerization of component (a) is
g, by using a catalyst system and a production method of 2,000 g or more per hour, the production efficiency is high, and there is no reduction in heat resistance or coloring due to the catalyst residue in the polymer, so that it is not necessary to remove the catalyst, which is preferable.

As described above, the component (b) is produced by producing the component (a) and subsequently polymerizing it in the same polymerization tank, or by producing the component (a) and then polymerizing it in a different polymerization tank. Although the case may be considered, a solvent polymerization method, a bulk polymerization method, a gas phase polymerization method, or a polymerization method comprising a combination thereof can be used for the latter polymerization method. In particular, a bulk polymerization method, a gas phase polymerization method, or a polymerization method comprising a combination thereof is preferred because of high polymerization activity and easy post-treatment.

Preferably, the polymerization rate in the production of the component (b) is controlled by the polymerization conditions so that the polymerization rate per g of the catalyst per hour is at least twice the polymerization rate in the production of the component (a). More preferably, it is three times or more. The polymerization temperature at this time may be the same as or different from the polymerization temperature of the component (a), but is usually in the range of 20 to 150 ° C, preferably 35 to 95 ° C. The polymerization rate of component (b) is 2 g of the polymerization rate of component (a) per 1 g of catalyst per hour.
If the ratio is less than twice, not only the production efficiency is inferior, but also it may be difficult to achieve the required ratio of the components (a) and (b) to the polymer.

The propylene polymer (A) used in the present invention
Is provided as a product after post-treatment of catalyst deactivation, desolvation, demonomerization, drying, granulation, etc., if necessary.

The propylene polymer composition used in the present invention is a resin composition containing 1 to 99 parts by weight of the above propylene copolymer (A) and 99 to 1 part by weight of the following propylene copolymer (B). Is preferred. In order to exhibit even better uniform stretchability, the propylene-based copolymer (A)
5 to 90 parts by weight and the following propylene-based copolymer (B) 9
A polymer composition containing 5 to 10 parts by weight is more preferable.
In addition, the total of the polymer composition is adjusted to be 100 parts by weight. The same applies to the following polymer compositions. (B): content of repeating units derived from propylene (hereinafter referred to as “propylene units”) 98 to 60
% By weight of a repeating unit derived from ethylene (hereinafter, referred to as
Content of "ethylene unit") of 0 to 15% by weight,
A repeating unit derived from 1-butene (hereinafter, “1-
Propylene-based copolymer having a content of 0 to 25% by weight

The propylene-based polymer composition used in the present invention comprises 1 to 98 parts by weight of a propylene-based copolymer (A), 98 to 1 part by weight of a propylene-based copolymer (B) and the following propylene-based polymer (C) A) a polymer composition containing 1 to 20 parts by weight (provided that the propylene-based copolymer (B) and the propylene-based polymer (C) are the same, and that the propylene-based copolymer (B) is The content of the ethylene unit is more than 2% by weight or more with respect to the propylene polymer (C), or the content of the 1-butene unit is more than 4% by weight or more with respect to the propylene polymer (C). Is a copolymer). In order for the polymer composition to exhibit good uniform stretchability, 3 to 90 parts by weight of the propylene-based copolymer (A), 94 to 7 parts by weight of the propylene-based copolymer (B), and A polymer composition containing 3 to 15 parts by weight of the combined (C) is more preferred. Further, in order to widen the molding temperature range in which blow molding is possible, it is more preferable to contain the propylene-based copolymer (C) in an amount of 3% by weight or more.

In the present invention, in order to widen the molding temperature range capable of being blow-molded, 100 parts by weight of the propylene-based polymer (A) or the polymer composition further contains 0.5 part by weight or less of a crystal nucleating agent. Polymer compositions are preferred.
Further, 100 to 100 parts by weight of the propylene-based polymer (A) or the polymer composition is further added with a crystal nucleating agent of 0.05 to 0.1.
More preferred is a polymer composition containing 5 parts by weight. When the crystal nucleating agent exceeds 0.5 parts by weight, the effect is saturated,
There may be extra costs. Further, it is preferable to include a crystal nucleating agent in the propylene-based polymer composition because the injection molding cycle can be shortened. Examples of the crystal nucleating agent include a sorbitol-based nucleating agent, a special phosphate-based nucleating agent, and polyvinylcycloalkane, and one or more of these are used.

The biaxially stretch blow-molded container of the present invention is a container composed of the propylene-based polymer (A) or the propylene-based polymer composition. The molding method may be a one-stage method or a two-stage method.
The two-stage method is preferred in that good blow moldability and physical properties of the container are exhibited.

The propylene-based polymer or polymer composition used in the present invention can be prepared by a known method such as a melt flow rate in the presence or absence of an organic peroxide during melt-kneading after polymerization. Sex can be changed.
Further, the propylene polymer or polymer composition used in the present invention may contain, for example, an antioxidant, an ultraviolet absorber, an antistatic agent, a lubricant, an antifogging agent, a pigment, and the like, if necessary. .

[0035]

As described in detail above, according to the present invention,
A propylene-based polymer or polymer composition for biaxial stretch blow molding, which has good impact resistance and transparency and excellent uniform stretchability, and a biaxial stretch blow molded container can be provided.
In addition, the container of the present invention has the above-mentioned excellent characteristics, and thus has excellent transparency, uniform stretchability, and impact resistance at low temperatures, and is most suitable as a container for packaging and transporting various liquids. Further, the container of the present invention is suitable for a food container, a retort food container, a non-food container such as a detergent, a medical container such as an infusion solution, and the like.

[0036]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples. The measurement of each item in Examples and Comparative Examples was performed by the following method. (1) Propylene polymer component (a) and component (b)
The ratio was determined from the material balance at the time of polymerization. (2) Comonomer content Polymer Handbook (1995, published by Kinokuniya Bookstore)
Was measured by infrared spectroscopy according to the method described on page 616 et seq. (3) Mw / Mn value P. C. (Gel permeation chromatography) under the following conditions. Model: 150CV type (manufactured by Millipore Waters) Column: Shodex M / S 80 Measurement temperature: 145 ° C Solvent: orthodichlorobenzene Sample concentration: 5 mg / 8 mL A calibration curve was prepared using standard polystyrene. Standard polystyrene (NBS706: Mw /
(Mn = 2.0) Mw / Mn was 1.9 to 2.0. (4) Intrinsic viscosity 135 ° C. in tetralin solvent using an Ubbelohde viscometer
Was measured. (5) Melt flow rate (MFR) Based on JIS K7210, temperature 230 ° C, load 2.
It was measured at 16 kg-f. (6) Uneven thickness of container (uniform stretchability) A test piece was cut out at a height of 10 to 210 mm at the center of the body in a hollow container formed using the polymer composition to a width of 1 cm in the longitudinal direction. This test piece was cut out on four sides for each hollow container. The thickness of the four test pieces was measured using a Mitutoyo micrometer, and the difference between the maximum value and the minimum value was calculated. (7) Izod impact strength After heating for 5 minutes at 230 ° C with a heating press, 30 kg
It was heated an additional 5 minutes by pressurizing the f / cm ^2, at subsequent cooling press machine, 30 ° C., the pressure in the 30 kgf / cm ^2, 5
After cooling for a minute, a predetermined sample was obtained. The sample,
After standing at 23 ° C. and a relative humidity of 50% for 40 hours or more, the measurement was carried out in accordance with JIS K7110 after standing still for 24 hours or more in that condition or a constant temperature bath at a temperature of 0 ° C. (8) Drop strength 1 kg of water is placed in a hollow container molded using the polymer composition.
After filling, the container is allowed to stand in a low-temperature constant temperature bath at 5 ° C. for 24 hours or more, and then repeatedly erected free from the height of 1.5 m to the concrete floor with the bottom of the container facing down ten times. The presence or absence of breakage was observed. The residual ratio was measured from the number of undestructed 10 test containers. (9) Transparency (Haze) The shoulder of the molded hollow container having a height of 220 mm was cut out as a test piece, and the internal haze was measured in accordance with JIS K7105.

Example 1 (Synthesis of solid catalyst) After replacing a 200 LSUS reaction vessel equipped with a stirrer with nitrogen, 80 L of hexane, 6.55 mol of tetrabutoxytitanium, 2.8 of diisobutyl phthalate was used.
And 98.9 mol of tetraethoxysilane were added to obtain a uniform solution. Next, 51 L of a diisobutyl ether solution of butylmagnesium chloride having a concentration of 2.1 mol / L
Was gradually added dropwise over 5 hours while maintaining the temperature in the reaction vessel at 5 ° C. After completion of the dropwise addition, the mixture was further stirred at room temperature for 1 hour, then subjected to solid-liquid separation at room temperature, and washed three times with 70 L of toluene. Next, toluene was added so that the slurry concentration became 0.2 kg / L, and then diisobutyl phthalate 4 was added.
7.6 mol was added, and the reaction was carried out at 95 ° C. for 30 minutes. After the reaction, solid-liquid separation was performed, and the resultant was washed twice with toluene. Then, 3.13 mol of diisobutyl phthalate, 8.9 mol of butyl ether and 274 mol of titanium tetrachloride were added, and 1
The reaction was performed at 05 ° C for 3 hours. After the completion of the reaction, the mixture was subjected to solid-liquid separation at the same temperature, and washed twice with 90 L of toluene at the same temperature. Then, after adjusting the slurry concentration to 0.4 kg / L, 8.9 mol of butyl ether and 13 mg of titanium tetrachloride were added.
7 mol was added and the reaction was carried out at 105 ° C. for 1 hour. After completion of the reaction, solid-liquid separation was performed at the same temperature, and the mixture was diluted with 90 L of toluene at the same temperature.
After washing twice, it was further washed with 70 L of hexane three times and then dried under reduced pressure to obtain 11.4 kg of a solid catalyst component. The solid catalyst component contains 1.8% by weight of titanium atom, 20.1% by weight of magnesium atom, 8.4% by weight of phthalic ester, 0.3% by weight of ethoxy group and 0.2% by weight of butoxy group. Had no good particle properties. (Pre-activation of solid catalyst component) 3L internal volume made of SUS,
30. 1.5 L of n-hexane, triethylaluminum sufficiently dehydrated and degassed in an autoclave equipped with a stirrer
5 mmol, 3.75 mmol of t-butyl-n-propyldimethoxysilane and 15 g of the above solid catalyst component were added, and propylene 15 was added while maintaining the temperature in the vessel at 5 to 15 ° C.
g was continuously supplied over 30 minutes to perform preactivation. (Polymerization of Propylene Polymer Component (a)) In a SUS 300 L polymerization tank, while supplying a polymerization temperature of 55 ° C. and a polymerization pressure of 27 kg / cm ² G, supplying liquid propylene at 57 kg / h. , 76.8 mmol / h of triethylaluminum, 7.95 mmol / h of t-butyl-n-propyldimethoxysilane and 1.24 g / h of a preactivated solid catalyst component are continuously fed to substantially convert hydrogen. Perform propylene polymerization in the absence of
2.55 kg / h of polymer were obtained. At this time, the amount of the produced polymer was 1 g of the catalyst and 4100 g per hour, and as a result of sampling and analyzing a part thereof, the intrinsic viscosity was 7.5 dl / g. The obtained polymer was continuously transferred to the second tank without deactivation. (Polymerization of propylene polymer component (b)) 1 m of inner volume
^In a fluidized bed reactor with a stirrer of ³ , the polymerization temperature was 80
° C, polymerization pressure 18 kg / cm ² G, hydrogen concentration 3 in gas phase
While supplying propylene and hydrogen so as to maintain the vol%, propylene polymerization with the catalyst-containing polymer transferred from the first tank was continuously continued to obtain 15.9.
kg / h of polymer were obtained. The intrinsic viscosity of this propylene polymer (A) was 2.3 dl / g. Further, Mw / Mn of the propylene-based polymer (A) was 4.8. From the above results, the amount of polymer produced during the polymerization of the component (b) was 1 g of the catalyst, 22,000 g per hour, the polymerization weight ratio of the first tank and the second tank was 16:84, and the component (b) ) Was determined to be 1.3 dl / g. (Pelletization of polymer) For 100 parts by weight of this polymer powder, 0.1 part by weight of calcium stearate and 0.05 of Irganox 1010 (trade name, manufactured by Ciba-Geigy)
0.2 parts by weight of Sumireizer BHT (manufactured by Sumitomo Chemical Co., Ltd.) was added, mixed and melt-kneaded to obtain a pellet (X) having an MFR of 5.1 g / 10 min. Next, a propylene-ethylene-1-butene random copolymer (B)
(Manufactured by Sumitomo Chemical Co., Ltd., Noblene, content of ethylene unit: 4.2% by weight, content of 1-butene unit: 4.1)
95% by weight of a powder, 5% by weight of a propylene homopolymer (C) powder, and 0.2% by weight of a crystal nucleating agent (ADK STAB NA21 manufactured by Asahi Denka) with respect to 100% by weight of the polymer mixture. The resulting mixture was melt-kneaded in the presence of peroxide to obtain a pellet (Y) adjusted to have an MFR of 30 g / 10 minutes. Finally add 2 pellets (X)
After mixing 0 wt% and 80 wt% of pellets (Y) and melt-kneading, a polymer composition having an MFR of 30 g / 10 min was obtained. Next, the polymer composition was injection-molded at a cylinder temperature of 190 ° C. using an injection molding machine (Model J100E) manufactured by Japan Steel Works, Ltd., and was 29 mm in diameter, 123 mm in length and 3.9 m in thickness.
m and a preform weighing 29 g were obtained. This preform is drawn by a frontier stretch blow molding machine (EFB20).
00), and heated by an infrared heater and cooled by air to reduce the preform surface temperature to 110-1.
After heating and adjusting to 40 ° C., longitudinal stretching by a stretch rod and blowing by compressed air were performed to produce a rectangular biaxially stretched blow-molded container having a capacity of 1 L, a height of 275 mm and a width of 72 mm. Table 1 shows the physical properties of the resin composition and the evaluation results of the obtained container.

Comparative Example 1 Propylene-ethylene-1-butene random copolymer (manufactured by Sumitomo Chemical Co., Ltd., Noblene, content of ethylene unit: 2.2% by weight, content of 1-butene unit: 6. 0
95% by weight of powder, 5% by weight of propylene homopolymer, and a crystal nucleating agent (ADK STAB NA21 manufactured by Asahi Denka)
Of 0.2% by weight based on 100% by weight of the polymer mixture
The resulting mixture was melt-kneaded in the presence of peroxide to obtain a polymer composition adjusted to have an MFR of 30 g / 10 minutes. The polymer composition was used in the same manner as in Example 1 to produce a biaxially stretched blow molded container. Table 1 shows the physical properties of the polymer composition and the evaluation results of the obtained container.

[0039]

Table 1----------------------------------------------------------------------------------------------------------Example ------------ MFR g / 10 min 30 30 container uneven thickness mm 0.12 0.29 Izod impact strength ^{23 ℃ kg · cm / cm 2} 9.3 4.4 0 ℃ kg・ Cm / cm ² 2.9 1.8 Drop strength% 100 100 Haze% 0.4 0.2 −−−−−−−−−−−−−−−−−−−−−−−−−−−

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) C08L 23/16 B65D 1/00 A // B29K 23:00 B29L 22:00 F term (reference) 3E033 BA16 BB04 BB05 CA03 CA07 CA18 FA02 FA03 4F208 AA04 AA11 AA11E AB08 AR17 LA04 LB01 LG01 4J002 BB012 BB121 BB141 BB151 DH046 EC056 FD202 FD206

Claims (5)

[Claims] In a first step, a monomer comprising propylene as a main component is polymerized to produce a crystalline propylene polymer component (a) having an intrinsic viscosity of 5 dl / g or more. A crystalline propylene polymer component (b) having a limiting viscosity of less than 3 dl / g by polymerizing a monomer as a component
Is a propylene-based polymer obtained continuously, and the proportion of the component (a) in the propylene-based polymer is 0.05% by weight or more and less than 25% by weight; Viscosity less than 3 dl / g, Mw / Mn is 1
A propylene polymer for biaxial stretch blow molding, comprising a propylene polymer (A) having a value of less than 0. 2. The propylene polymer (A) according to claim 1.
1 to 99 parts by weight and the following propylene-based copolymer (B) 9
A propylene polymer composition for biaxial stretch blow molding, comprising a polymer composition containing 9 to 1 part by weight. (B): The content of the repeating unit derived from propylene is 98 to 60% by weight, the content of the repeating unit derived from ethylene is 0 to 15% by weight, and the content of the repeating unit derived from 1-butene is 0 to 0%. Propylene copolymer comprising 25% by weight 3. A polymer composition comprising 1 to 98 parts by weight of a propylene-based polymer (A) and a propylene-based copolymer (B) 9
8 to 1 part by weight and the following propylene polymer (C) 1 to 2
The propylene polymer composition for biaxial stretch blow molding according to claim 2, wherein the propylene polymer (B) and the propylene polymer (C) are the same. And the propylene-based copolymer (B) has a content of the repeating unit derived from ethylene of 2% by weight based on the propylene-based polymer (C).
This is a copolymer having a higher content or a content of the repeating unit derived from 1-butene of 4% by weight or more with respect to the propylene-based polymer (C). ). (C): The content of the repeating unit derived from propylene is 100 to 93% by weight, the content of the repeating unit derived from ethylene is 0 to 2% by weight, and the content of the repeating unit derived from 1-butene is 0. Propylene polymer comprising 5% by weight 4. A polymer composition further comprising 0.5 parts by weight or less of a crystal nucleating agent in 100 parts by weight of the propylene polymer or the propylene polymer composition according to claim 1. A propylene-based polymer composition for biaxial stretch blow molding, comprising: 5. A biaxially stretch blow-molded container comprising the propylene-based polymer or the propylene-based polymer composition according to claim 1.