JP2001106843A - Propylene based resin composition for container cover - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a synthetic resins for a container cover having large die swelling due to memory effect to excel in moldability, high rigidity, and high impact resistance. SOLUTION: This propylene based resin composition for a container cover comprises 100 pts.wt. propylene based resin, 3.0-15 pts.wt. ethylene based polymer polymerized by using a metallocene compound which has (A) an MFR of 0.1-50 g/10 min and (B) a maximum peak temperature in the elution curve obtained by temperature raising elution fractionation of 15-85 deg.C and an H to W value when the peak height is regarded as H and the peak width at a height of 1/3 of the peak height is regarded as W, of not smaller than 2, 0.01-1.0 pt.wt. nucleating agent, and 0.1-7.0 pts.wt. titanium oxide based pigment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a propylene resin composition for a container lid. More specifically, it is used as a material for a beverage container lid such as a tea-based beverage container, a fruit juice beverage container, a carbonated beverage container, and particularly a lid for a resin beverage container, and is constituted by an extrusion molding machine and a compression molding machine. The present invention relates to a propylene-based resin composition which is suitable for molding a lid for a beverage container using a molding machine and has excellent rigidity.

[0002]

2. Description of the Related Art Conventionally, tea beverage containers, fruit juice beverage containers,
As beverage containers such as carbonated beverage containers, polyethylene terephthalate (PET) resin bottles or glass bottles have been used, and metals such as aluminum have been used for lids of these containers. However, in recent years, there has been a demand for recycling and reusing beverage containers from the viewpoint of global environmental protection. However, used beverage containers such as fruit juice beverage containers and carbonated beverage containers are often collected with their lids attached since a considerable portion is discharged from each household.

[0003] For this reason, the container and the lid can be easily separated mechanically, or used as a recycled resin even if the container and the lid are collected without being separated. In recent years, synthetic resin lids have become widespread as alternatives to metal lids for ease of use. As a synthetic resin lid, workability, mechanical physical properties, appearance, durability, chemical resistance,
Electrical properties and economy are required, and it is necessary to have recyclability.

In particular, it is required that the rigidity of the resin and the die swell due to the memory effect at the time of extrusion molding be large. The reason why die swell is required is as follows. That is, as shown in FIG. 1, a synthetic resin lid is molded and melted and kneaded by an extruder 1 and then extruded from a die 2 into a strand shape, as shown in FIG. It is cut to a fixed length by the rotating cutter 3.

[0005] The molten resin formed into a fixed amount of pellets 6 by being cut into a fixed length is charged into lid forming dies 5, 5 mounted on a turntable 4 arranged below. After that, it is pressed by the molding plunger 7 with the rotation of the turntable 4 to be formed into a lid. In this case, the shape and cross-sectional diameter of the molten resin pellet 6 are important, and if the shape is irregular or the cross-sectional diameter is not compatible with the lid-forming dies 5, 5,
When pressed by the molding plunger 7, there is a problem that the flow of the molten resin becomes uneven, causing chipping or a decrease in dimensional accuracy.

Therefore, the cutting of the molten resin strand by the cutter 3 needs to always obtain pellets 6 having a constant shape, and to have a constant sectional diameter. Thus, the cross-sectional diameter of the cut molten resin pellets 6 depends on the diameter of the extruded molten resin strand, but the diameter of the molten resin strand is not limited to the diameter of the orifice of the extrusion die 2 and the diameter of the extruded molten resin. Die swell due to the memory effect occurs during molding, and is determined by its size. The size of the die swell of the molten resin also varies depending on the conditions of extrusion molding.

On the other hand, the lid for the container is molded under the respective conditions by a moulder.
Various requirements are placed on the material properties from the respective molders to the resin manufacturers in order to conform to the requirements of No. 5. In order to meet these requirements, it is desirable to use a resin having a large die swell so that the resin can be adjusted by the die swell. In addition, a resin having a large die swell has excellent moldability, and can provide a container lid having high rigidity and high impact resistance. However, at present, development of such a resin for a container lid having a large die swell has not progressed.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a resin composition for a container lid having a large die swell due to a memory effect, excellent moldability, high rigidity, and high impact resistance.

[0009]

Means for Solving the Problems The present invention has been made as a result of intensive studies to achieve the above object, and the following polymerized using a metallocene compound with respect to 100 parts by weight of a propylene-based resin. 3.0 to 15 parts by weight of an ethylene polymer having properties (1) and (2),
01 to 1.0 part by weight, and titanium oxide pigment 0.1 to
It is intended to provide a propylene-based resin composition for a container lid characterized in that 7.0 parts by weight are blended. (1) The MFR is 0.1 to 50 g / 10 min. (2) The temperature of the maximum peak of the elution curve obtained by the temperature increase elution fractionation is 15 to 85 ° C. The width of the peak at one third height is W
H / W value is 2 or more

[0010]

DETAILED DESCRIPTION OF THE INVENTION The propylene resin composition for container lids of the present invention comprises (A) a propylene resin, (B) an ethylene polymer having specific physical properties, (C) a nucleating agent and (D)
It is composed of a titanium oxide-based pigment. (A) Propylene resin As the propylene resin, a propylene homopolymer or a copolymer of propylene and another α-olefin can be used, and among them, a propylene / ethylene block copolymer is preferable.

The propylene resin has an MFR of 1.
0 to 20 g / 10 min, preferably 2 to 15 g / 10 min,
A propylene resin having an isotactic pentad fraction of 0.96 or more, preferably 0.97 or more, particularly preferably 0.98 or more is used. MFR value of 1.0 g /
If the time is shorter than 10 minutes, the discharge stability of the molten resin (strand) when manufacturing the container lid is deteriorated, the pressure of the discharged resin is increased, and the moldability is reduced. If the value of MFR is higher than 20 g / 10 minutes, the cutting properties, pellet properties, etc. of the molten resin at the time of manufacturing the container lid deteriorate, and the moldability deteriorates.

[0012] tightening between the container, especially when the lid,
Preferably, it has the above physical properties and has a bending elasticity of 1.18 × 10 ⁹ Pa (12,000 kg / cm ² ) in terms of gas pressure resistance.
Above all, especially 1.57 × 10 ⁹ Pa (16,000 kg
/ Cm ² ) or more. If the value of the isotactic pentad fraction is too low, the rigidity is insufficient, and it is not suitable for a lid.

(Production of Propylene Resin) The polymerization method and catalyst of the propylene resin used in the present invention are not particularly limited as long as a polymer having desired physical properties can be produced. As for the catalyst, a Ziegler type catalyst (ie, based on a combination of a supported or unsupported halogen-containing titanium compound and an organoaluminum compound), a Kaminski type catalyst (ie, a supported or unsupported metallocene compound and an organoaluminum compound, particularly alumoxane) Based on a combination).

For example, it can be obtained by a usual polymerization method using a combination catalyst of an organoaluminum compound and a solid catalyst component comprising magnesium halide, titanium halide, and an electron donor compound. For the purpose of increasing the crystallinity of the propylene polymer, a third component can be added during the polymerization.

As the electron donor compound in the solid catalyst component, organic acid esters, organic silicon compounds and the like are preferably used. As the third component at the time of polymerization, an organic silicon compound is preferably used. For example, JP-A-61-78
03, JP-A-62-1705, JP-A-62-111
No. 706 can be adopted.

The metallocene compound used for the Kaminski type catalyst includes Zr, Ti, Hf, etc.
An organic transition metal compound of a Group 4 transition metal compound, particularly a Group 4 transition metal compound, and cyclopentadiene or a cyclopentadiene derivative can be used. As the cyclopentadiene derivative, an alkyl substituent such as pentamethylcyclopentadiene or a compound in which two or more substituents are combined to form a saturated or unsaturated cyclic substituent can be used, and typically, indene, Examples thereof include fluorene, azulene, and partially hydrogenated products thereof. Further, a compound in which a plurality of cyclopentadienes are bonded by an alkylene group, a silylene group, or the like can also be used. As the co-catalyst, a compound capable of reacting with an organoaluminum or metallocene catalyst to form stable ions can be used, and alumoxane is generally used.

The propylene polymer of the present invention is a crystalline one produced using the stereoregular catalyst. The polymerization may be a continuous type or a batch type, and a slurry polymerization method using an inert hydrocarbon solvent, a bulk polymerization method using propylene itself as a solvent, or a gas phase polymerization method can be employed. 1.96 ° C, normal pressure to 1.96
The polymerization reaction is performed at a pressure of × 10 ⁷ PaG (200 kg / cm ² G). Adjustment of the MFR at the time of polymerization can be performed by using hydrogen as a molecular weight regulator.

(B) Ethylene Polymer The component (B) ethylene polymer of the present invention preferably comprises an ethylene unit as a main component and an α-olefin unit as a subcomponent (comonomer unit).

The proportion of ethylene units in the copolymer is preferably at least 80 mol%, and the comonomer is preferably at least 20 mol%.
It is as follows. As a method of controlling the molecular weight and the distribution of crystallinity, a method of adjusting the polymerization temperature and the amount of the comonomer is appropriately employed, whereby a polymer having desired physical properties can be obtained.

It is important that the polymer of the component (B) has the following physical properties (1) and (2). (1) MFR The ethylene polymer used in the present invention is JI
MFR by SK-7210 (Melt flow rate:
(Melt flow rate) 0.1 to 50 g / 10 min, preferably 0.1 to 50 g / 10 min.
Those having 3 to 40 g / 10 minutes are used. If the MFR is larger than the above range, the cutting property of the resin is deteriorated, and if the MFR is smaller than the above range, the resin pressure is undesirably high.

(2) Maximum peak of elution curve by temperature-rise elution fractionation (TREF) The polymer used in the present invention has a maximum peak temperature of the elution curve obtained by the temperature-rise elution fractionation of 1
H / W is 5 to 85 ° C., preferably 25 to 82 ° C., and the height of the peak is H, and the width of the peak at one third of the height is W, the value of H / W is 2 Above, preferably 2.5 or more are used.

Here, the temperature rise elution fractionation (TREF: T
emperature RisingElution
Fraction means that once the polymer is completely dissolved, it is cooled, a thin polymer layer is formed on the surface of the inert carrier, and then the temperature is raised continuously or stepwise to recover the eluted component (polymer). In this method, the concentration is continuously detected to determine the amount of the eluted component and the elution temperature.

A graph drawn by the elution fraction and the elution temperature is an elution curve, from which the composition distribution (molecular weight and crystallinity distribution) of the polymer can be measured. For details of the method and apparatus for measuring the temperature rise elution fractionation (TREF), see Journal of Appl.
ied Polymer Science, Vol. 26,
4217-4231 (1981).

The shape of the elution curve obtained by TREF depends on the molecular weight and crystallinity distribution of the polymer.
For example, there are one peak, two peaks, and three peaks, and the two-peak curve has a higher elution fraction for a peak having a higher elution temperature than a peak having a lower elution temperature. There is a case where the peak has a high elution temperature and a case where the peak having a high elution temperature has a small fraction (the height of the peak is low) as compared with a peak having a low elution temperature.

FIG. 2 shows an elution curve for one peak, FIG. 3 shows an elution curve for two peaks, and FIG. 4 shows a three-peak elution curve. FIG. 3 (a) shows a case where a peak having a higher elution temperature has a higher peak height than a peak having a lower elution temperature, and FIG. 3 (b) shows a case where the elution temperature is lower. A peak having a higher elution temperature has a lower peak height than a peak.

In the present invention, the maximum peak of the elution curve refers to the peak in the elution curve having one peak and the maximum peak in the elution curve having two or more peaks.
The peak at which the eluted fraction is the maximum (FIGS. 3 and 4,
(Peak indicated by p). In addition, H / W in the present invention is obtained by calculating the height of the maximum peak as H and the width at one third of the height as W as shown in FIGS. .

As shown in FIG. 2, when there is one peak, it is obtained from the height and width of the peak.
In one or more elution curves, the valley between the maximum peak and another peak may be one-third or more of the height of the maximum peak. The width at one-half height may be the width of the curve formed from the maximum peak and other peaks. In this case, the width of the entire curve formed from the maximum peak and other peaks is W (see 3 (a) and FIG. 4). Even if there are two or more peaks, if there is another peak whose valley between the maximum peak is less than one third of the height of the maximum peak, such another peak is It does not participate in the calculation of the width W (see FIG. 3B).

The TRE of the present invention thus determined
When the temperature and H / W of the maximum peak of the elution curve due to F are within the above ranges, an ethylene polymer having a narrow composition distribution and uniform crystallinity can be obtained, and low crystalline / low molecular weight components are small. There is no contamination of the protection. When the temperature of the maximum peak of the elution curve by TREF is higher than the above range, a large amount of highly crystalline components are present in the resin, and the balance between rigidity and impact resistance is deteriorated. On the other hand, if the peak temperature is lower than the above range, heat resistance deteriorates and stickiness occurs, which is not preferable. On the other hand, if the value of H / W is smaller than the above range, slippage is poor and stickiness occurs, which is not preferable.

The ethylene / α-olefin copolymer having the above-mentioned physical properties has a structural unit derived from ethylene as a main component, and the α-olefin used as a comonomer has 1 to 3 carbon atoms. -Olefins, specifically, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-heptene,
-Methyl-pentene-1, 4-methyl-hexene-1,
4,4-dimethylpentene-1 and the like can be mentioned. As the comonomer, the above-mentioned α-olefin is not limited to one kind, and a multi-component copolymer using two or more kinds such as a terpolymer is also preferably included. The proportion of ethylene units in the copolymer is preferably at least 80 mol%, and the comonomer is at most 20 mol%.

The ethylene polymer in the present invention is polymerized by a Kaminski catalyst using a metallocene compound. As the metallocene compound used for the Kaminsky type catalyst, an organic transition metal compound of a Group 4 to 6 transition metal compound such as Zr, Ti, and Hf, particularly a Group 4 transition metal compound and cyclopentadiene or a cyclopentadiene derivative is used. can do. As the cyclopentadiene derivative, an alkyl substituent such as pentamethylcyclopentadiene or a compound in which two or more substituents are combined to form a saturated or unsaturated cyclic substituent can be used, and typically, indene, Fluorene, azulene, or partially hydrogenated products thereof can be mentioned.

Further, a compound in which a plurality of cyclopentadiene are linked by an alkylene group, a silylene group or the like can be used. As the co-catalyst, a compound capable of reacting with an organoaluminum or metallocene catalyst to form stable ions can be used, and alumoxane is generally used.

Ethylene / α using Kaminski type catalyst
-Specific methods for producing olefin copolymers include JP-A-58-19309, JP-A-59-95292,
JP-A-60-35005, JP-A-60-35006
JP-A-60-35007, JP-A-60-3500
No. 8, JP-A-60-35009, JP-A-61-130
No. 314, JP-A-3-1630088, European Patent Application Publication No. 420,436, U.S. Pat. No. 5,055,438, and International Publication W.
No. 091/04257, etc.
That is, a metallocene catalyst, a metallocene / alumoxane catalyst, or, for example, WO09 / 07123.
And the like, using a metallocene compound and a metallocene catalyst, which is a compound comprising a compound capable of reacting with a metallocene catalyst to form stable ions, as disclosed in US Pat. Examples thereof include a method of copolymerizing with an olefin.

Examples of the polymerization method include a slurry method in the presence of these catalysts and a gas-phase fluidized-bed method (for example, see JP-A-59-2).
No. 3011), a solution method, or a pressure of 1.96 × 10 ⁸ Pa (2000 kg / cm ² ) or more,
A high-pressure bulk polymerization method at a polymerization temperature of 100 ° C. or higher is exemplified. As a method for obtaining the ethylene-based polymer specified by the present invention, for example, a desired polymer can be obtained by adjusting the polymerization temperature and the comonomer amount and appropriately controlling the molecular weight and the distribution of crystallinity. Component (B) is added in an amount of 3 parts by weight based on 100 parts by weight of the propylene-based resin.
0 to 15 parts by weight, preferably 5.0 to 10 parts by weight. If the addition amount is less than 3.0 parts by weight, there is no effect of improving die swell, while if it exceeds 15 parts by weight, rigidity decreases.

(C) Nucleating agent As the nucleating agent, various types can be used.
Aromatic aluminum nucleating agent, aromatic sodium nucleating agent, aromatic metal phosphate nucleating agent, sorbitol nucleating agent,
Metal salts of rosin, talc and the like can be mentioned. Among them, an aromatic metal phosphate nucleating agent is preferable. As the aromatic metal phosphate nucleating agent, a compound represented by the following general formula 1 can be exemplified.

[0035]

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Wherein R represents a direct bond, a sulfur atom or an alkylidene group, R ₁ and R ₂ each represent a hydrogen atom, an alkyl group or a cycloalkyl group; l and m each represent 0 or 1; Represents a valence of a metal element, and M represents a metal atom.) Examples of the alkylidene group represented by R in the phosphorus-based nucleating agent represented by the above general formula 1 include methylidene, ethylidene, butylidene, hexylidene, octylidene, and cycloalkyl. Pentylidene, cyclooctylidene and the like.

The alkyl groups represented by R ₁ and R ₂ include methyl, ethyl, isopropyl, n-butyl, isobutyl, t-butyl, n-amyl, n-hexyl, n-
Octyl, 2-ethylhexyl, octadecyl and the like can be mentioned. Examples of the cycloalkyl group represented by R ₁ and R ₂ include cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl and the like.
As the metal atom represented by, Li, Na, K, Be,
Mg, Ca, Sr, Ba, Zn, Al, Sn, Ti,
Zr, Sb, Mo, Mn, Co, Ni and the like can be mentioned. Representative compounds among the compounds represented by the above general formula 1 are described in JP-B-63-8980, which are shown below. Representative compounds among these compounds are as follows: 1 methylenebis (2,4-di-
(t-butylphenol) acid phosphate Na salt.

The amount of addition is from 0.01 parts by weight to 1.0 part by weight.
Parts by weight, preferably 0.1 to 0.5 parts by weight. If the amount is less than 0.01 part by weight, the effect of improving the rigidity is small, and if it exceeds 1.0 part by weight, economical efficiency is deteriorated, which is not preferable.

[0039]

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[0040]

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[0041]

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[0042]

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[0043]

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[0044]

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[0045]

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(D) Titanium Oxide Pigment The titanium oxide pigment may be of a rutile type or an anatase type. Further, those which are surface-treated with silicon oxide, aluminum oxide or the like are preferable, and those which are coated with a surfactant or the like for improving dispersibility are also preferable. The amount of addition is 0.1 to 7.0 parts by weight, preferably 0.3 to 5.0 parts by weight. When the amount is less than 0.1 part by weight, the color tone becomes uneven, and when the amount is more than 7.0 parts by weight, it is economically disadvantageous and the moldability is lowered.

(Ingredients) The propylene-based resin composition for container lids may be modified with the following modifiers within a range that does not significantly impair the effects of the present invention. Target components can also be blended.

(Modifier) As a modifier, an unsaturated organic acid or its anhydride (for example, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid) or unsaturated ester (for example, vinyl acetate, Acrylate, methyl methacrylate, etc.), vinyl silane, aromatic vinyl silane, and the like. Further, a mixture with these modified polymers can be used.

(Additional Components) Examples of additional components include antioxidants (phenol-based, phosphorus-based, sulfur-based, etc.), light stabilizers, ultraviolet absorbers, neutralizers, lubricants (silicone oil, etc.), Antistatic agents, flow improvers, molecular weight regulators (peroxides), antiblocking agents, fillers (eg, talc, mica, clay, wollastonite, zeolite, calcium carbonate, aluminum hydroxide, magnesium hydroxide, Barium sulfate, calcium silicate, etc.), impact modifiers, foam inhibitors, dispersants, metal deactivators, antibacterial agents, fluorescent brighteners,
Coloring agents (titanium oxide, titanium yellow, zinc white, red petals,
Compounding agents such as inorganic pigments such as ultramarine blue, condensed azo-based, isoindolinone-based, quinacridone-based, perinone-based, perylene-based, quinophthalone-based, anthraquinone-based, and phthalocyanine-based organic pigments), or other resins And an elastomer component.

(Formation of Container Lid) Compounding The propylene resin composition for a container lid described above was compounded with various compounding ingredients, if necessary.
Mixing or melting and kneading with a usual mixing or kneading machine such as a super mixer, a V blender, a tumbler mixer, a ribbon mixer, a Banbury mixer, a kneader blender, a single or twin screw extruder, preferably at a temperature of 160
The mixture is melt-kneaded at ~ 300 ° C, preferably 180-280 ° C, and pelletized to obtain a molding material.

The molding material is melt-kneaded in an extruder 1 and extruded from a die 2 into a strand as shown in FIG.
It is cut to a predetermined length by the cutter 3. The molten resin pellets 6 cut into a certain amount are put into lid forming dies 5, 5 mounted on the turntable 4, and then the turntable 4 is rotated and pressed by the plunger 7 to be formed.

By molding the lid of a beverage container or the like using the propylene resin composition for a container lid of the present invention as a molding material, molding such as extrudability, cutting property of molten resin, fidelity to a mold and the like can be achieved. It is excellent in property and can improve productivity. Examples of a molding method capable of suitably molding the container lid include a production method described in JP-A-58-51116.

[0053]

The present invention will be described more specifically with reference to the following experimental examples.

(Measurement method) a. MFR MFR is a value measured according to JIS K-7210 (temperature 230 ° C., load 2.16 kg).

B. Elution curve obtained by temperature-rise elution fractionation (TREF) The peak of the elution curve by temperature-rise elution fractionation (TREF) in the present invention is such that once the polymer is completely dissolved at a high temperature, it is cooled, and the surface is thin on the inert carrier surface. A polymer layer is formed, and then the temperature is continuously or stepwise raised to recover the eluted component (polymer). The temperature is continuously detected, and the amount of the eluted component (elution amount) is determined. The elution temperature is determined by a method. The peak of the elution curve of the present invention is determined from the graph (elution curve) drawn thereby, and the composition distribution of the polymer is measured.

The measurement of the elution curve was specifically performed as follows. The measurement was carried out using a cloth separation device (CFC T150A, manufactured by Mitsubishi Chemical Corporation) as a measurement device according to the measurement method in the attached operation manual. This cross-separation apparatus uses a temperature-rise elution separation (TREF) mechanism for separating a sample by using a difference in dissolution temperature, and a size exclusion chromatograph (Size Exclusion Chromatog) for further separating the separated fraction according to molecular size.
(SECRY) is connected online.

First, the sample to be measured (ethylene / α
-Olefin copolymer) using a solvent (O-dichlorobenzene) to give a concentration of 4 mg / ml.
It was melted at ℃ and injected into a sample loop in the measuring device. The following measurements were performed automatically according to the set conditions.

The sample solution held in the sample loop is separated using a TREF column (inside diameter of 4 m filled with glass beads as an inert carrier) by utilizing the difference in dissolution temperature.
m, 150 mm length stainless steel column attached to the device)
Was injected 0.4 ml. The sample was cooled at a rate of 1 ° C./min from 140 ° C. to 0 ° C. and coated on the inert carrier. At this time, from the high crystal component (the one that is easy to crystallize) to the low crystal component (the one that hardly crystallizes)
The polymer layer is formed on the surface of the inert carrier in this order.

After holding the TREF column at 0 ° C. for an additional 30 minutes, 2 ml of the dissolved component at a temperature of 0 ° C. was added to 1 m
The mixture was injected from a TREF column into a SEC column (AD80M.S, manufactured by Showa Denko KK, three tubes) at a flow rate of 1 / min. SEC
In the TREF column, the temperature was raised to the next elution temperature (5 ° C.) while the fractionation by the molecular size was being performed, and the temperature was maintained for about 30 minutes. The measurement of each elution section by SEC was performed at intervals of 39 minutes. The following temperature was used as the elution temperature, and the temperature was raised stepwise.

Elution temperature (° C.): 0, 5, 10, 15, 2
0, 25, 30, 35, 40, 45, 49, 52, 5
5,58,61,64,67,70,73,76,7
9,82,85,88,91,94,97,100,1
02,120,140 ° C

With respect to the solution fractionated by the molecular size in the SEC column, the absorbance in proportion to the concentration of the polymer was measured with an infrared spectrophotometer attached to the apparatus (wavelength 3.42 μm).
m, methylene chloride), and chromatograms of each elution temperature category were obtained. Using built-in data processing software,
A baseline of the chromatogram of each elution temperature section obtained by the above measurement was drawn and subjected to arithmetic processing. The area of each chromatogram was integrated and an integrated elution curve was calculated. Also,
This integrated elution curve was differentiated by temperature to calculate a differential elution curve. The plot of the calculation results was output to a printer. In the plot of the output differential elution curve, the elution temperature is plotted on the horizontal axis.
The difference was 89.3 mm per 0 ° C. and the differential amount on the vertical axis (elution fraction: the total integrated elution amount was standardized to 1.0, and the change at 1 ° C. was defined as the differential amount) at 76.5 mm per 0.1. . Next, the highest peak (maximum peak) from this differential elution curve
At the maximum peak temperature, the peak height of this maximum peak was H, and the width at one third of the height was W, the value of H / W was calculated.

C. Isotactic pentad fraction The isotactic pentad fraction is an isotactic fraction in pentad units in a polypropylene molecular chain measured using ¹³ C-NMR (nuclear magnetic resonance method).
The actual measurement of ¹³ C-NMR was 270 M of FT-NMR.
Hz.

D. Flexural modulus The flexural modulus was measured according to JIS K-7203. The test piece of the flexural modulus was molded by an injection molding machine at a resin temperature of 240 ° C. and a mold cooling temperature of 40 ° C. for measurement.

E. Izod impact strength Measured according to JIS K-7110. The test piece of Izod impact strength was resin temperature 240 ° C by an injection molding machine.
Molding was performed at a mold cooling temperature of 40 ° C., and the measurement was performed.

F. Memory Effect (ME) The measurement of the Memory Effect (ME) was performed by setting the temperature in the cylinder of the melt indexer to 190 ° C. and setting the length to 8.
An orifice having a diameter of 00 mm, a diameter of 1.00 mm, and L / D = 8 is used. A graduated cylinder containing ethyl alcohol is placed directly below the orifice. The distance between the orifice and the liquid level of ethyl alcohol is set to 20 ± 2 mm. In this state, the sample was put into a cylinder, and the load was adjusted so that the amount of the extruded product per minute was 0.10 ± 0.03 g.
After 7 to 7 minutes, the extrudate is dropped into ethanol, solidified and collected. Next, the diameter of the strand-shaped sample of the extruded product was measured at the maximum value and the minimum value at three points of 1 cm from the upper end, 1 cm from the lower end, and the central part. It is called a memory effect (ME).

[0066]

Example 1 (Production of composition) Propylene / ethylene block copolymer (BC3B, MFR 10 g / 10, manufactured by Nippon Polychem Co., Ltd.)
100 parts by weight of a metal effect (ME) 1.15, pentad fraction 97) and an ethylene polymer (KS56 manufactured by Nippon Polychem Co., Ltd.) polymerized using a metallocene catalyst.
0, comonomer: butene-1, MFR16, temperature of the maximum peak of the elution curve obtained by temperature-rise elution fractionation 5
8 ° C., H / W value 4.0), high-pressure low-density polyethylene (LJ800 manufactured by Nippon Polychem Co., Ltd., density 0.918 g / c)
m ³ ), high-density polyethylene (HJ3 manufactured by Nippon Polychem Co., Ltd.)
40, a density of 0.953 g / cm ³ ), EP rubber (EP02P manufactured by Nippon Synthetic Rubber Co., Ltd.) and EB rubber (A4090 manufactured by Mitsui Chemicals, Inc.) in the proportions shown in Table 1, and titanium oxide (Ishihara) 1.0 parts by weight of CR80 manufactured by Sangyo Sangyo Co., Ltd., and methylene bis (2,4-di-t-butylphenol) acid phosphate Na salt (N
A11) 0.2 part by weight, 0.05 part by weight of calcium stearate as a neutralizing agent, phenolic antioxidant pentaerythritol-tetrakis [3- (3,5-di-t-
Butyl-4-hydroxyphenyl) propionate)]
(Ciba-Geigy RA1010) 0.05 parts by weight and tris (2,4-di-t-butylphenyl) phosphite (Ciba-Geigy RA168) 0.05 parts by weight were added and pelletized to form a container lid. A propylene-based resin composition was manufactured.

(Molding) The above propylene resin composition for container lid was evaluated as a propylene polymer material for beverage container lid. Table 1 shows the results.

[0068]

[Table 1]

[0069]

The propylene resin composition for a container lid of the present invention has a large die swell due to a memory effect,
It is a lid material for polypropylene beverage containers excellent in moldability such as extrusion stability, cutting properties of molten resin, fidelity to molds, etc., especially in container lid molding machines composed of extruders and compression molding machines. Excellent moldability, especially production stability during high speed molding. The resulting propylene-based resin lid is excellent in rigidity, impact resistance, appearance, durability, chemical resistance, electrical properties, economy, etc., and excellent in recyclability, and is extremely industrially It is a useful material.

[Brief description of the drawings]

FIG. 1 is a side view of a molding machine showing a method of molding a container lid.

FIG. 2 is a graph showing a single peak in an elution curve obtained by temperature-rise elution fractionation.

FIG. 3 is a graph showing a case where the elution curve obtained by temperature-rise elution fractionation has two peaks.

FIG. 4 is a graph showing a case where the elution curve obtained by temperature-rise elution fractionation has three peaks.

[Explanation of symbols]

 1. Extruder 2. Die 3. Cutter 4. Turntable 5. Lid molding die 6. 6. molten resin pellets Plunger

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 23:08) C08L 23:08) (72) Inventor Tatsuo Kobayashi 1 Tohocho, Yokkaichi-shi, Mie Japan Nippon Polyke F Co., Ltd. Material Development Center F term (reference) 4F071 AA15 AA20 AA88 AB18 AC13 AC15 AH05 BC04 4J002 AF023 BB052 BB111 DE137 DJ046 EC056 EW036 EW046 FD097 FD203 FD206 GG01 4J028 AA01A AB01A AC01AAC10B00B ACB EB08 EB09 EB10 EC02 FA02 FA04 FA06 FA07 GA07

Claims (2)

[Claims] 1. The method according to claim 1, wherein 100 parts by weight of the propylene resin is
The following physical properties polymerized using metallocene compounds (1)
And 3.0 to 15 parts by weight of an ethylene polymer having (2) and (2), 0.01 to 1.0 part by weight of a nucleating agent, and 0.1 to 7.0 parts by weight of a titanium oxide pigment. A propylene-based resin composition for a container lid, comprising: (1) The MFR is 0.1 to 50 g / 10 min. (2) The temperature of the maximum peak of the elution curve obtained by the temperature increase elution fractionation is 15 to 85 ° C. The width of the peak at one third height is W
H / W value is 2 or more 2. A propylene-based resin having an MFR of 1 to 20 g /
The propylene-based resin composition for a container lid according to claim 1, wherein the isotactic pentat fraction is 0.96 or more for 10 minutes.