JP2014070216A - Thermoplastic resin composition and molding of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic resin composition having high heat resistance, flexibility and high transparency, and to provide a molding using the same.SOLUTION: Provided is a thermoplastic resin composition comprising 90-99.5 parts.wt. of a propylene-ethylene block copolymer [I] satisfying the following (i) through (v) and 0.5-10 parts.wt. of a thermoplastic elastomer [II] immiscible with [I] (the combined sum of both is 100 parts.wt.): (i) that it is obtained by consecutively polymerizing, by using a metallocenic catalyst, 30-95 wt.% of (A) a component consisting of propylene alone or a propylene-ethylene random copolymer having an ethylene content of 7 wt.% or below at the first step and 70-5 wt.% of (B) a propylene-ethylene random copolymer component having an ethylene content higher than that of the component (A) by 3-20 wt.% at the second step, (ii) that the MFR is 0.5-100 g/10 min, (iii) that the melting peak temperature (Tm) is 110 to 150°C, (iv) that the molecular weight distribution (Mw/Mn) is 1.5-4, and (v) that a tanδ curve in a temperature-loss tangent curve possesses a single peak at 0°C or below.

Description

  The present invention relates to a thermoplastic resin composition and a molded article thereof, and particularly relates to a thermoplastic resin composition having high heat resistance and flexibility and having high transparency and a molded body using the same.

  Olefin-based thermoplastic elastomers or olefin-based resin materials such as plastomer, polyethylene, and polypropylene are used for container members for storing various contents. These materials are widely used in this application because they have high environmental compatibility such as recycling and waste incineration, and are excellent in economy and moldability.

  Among such container members, the fitting container for storage in which the lid and the container main body are fitted is easy to seal the contents, and since the contents can be repeatedly sealed and stored, the food, Widely used for storage of beverages, pharmaceuticals, industrial products, etc. In such applications, transparency that allows visual confirmation of the contents, flexibility to prevent the contents from leaking out and easy opening, and use in cold regions And cold resistance that can withstand refrigeration and freezing storage is required. Also, in recent years, these containers have undergone an increasing number of heating processes such as heat sterilization when filling their contents, reheating with a microwave oven, washing and drying with a dishwasher, and their deformation and size change. It is also necessary to have excellent heat stability such that the appearance and appearance do not change.

  However, the olefin resin material used for this application has the following problems that should be further improved and improved in each property.

  That is, olefin elastomers or plastomers are very flexible and have high cold shock resistance, but have the disadvantage of extremely low heat resistance. For this reason, in applications where the container and its contents are sterilized by heating, the container is washed with a dishwasher, or heated with a microwave oven, etc., there is a problem of deformation or dimensional change of the container. Can not.

  In addition, polyethylene, particularly medium density or low density polyethylene, has moderate flexibility and cold resistance, so it is widely used as a fitting container member, but its heat resistance is superior to that of olefin elastomers. Insufficient use at 100 ° C. or higher is still insufficient. Furthermore, the transparency tends to be slightly inferior, and there is a problem in the internal visibility in a molded product having a relatively large thickness such as an injection molded product.

Polypropylene has high heat resistance, but has low flexibility and cold resistance, and insufficient transparency.
On the other hand, what is called a block type reactor TPO, which produces crystalline polypropylene in the first step and produces a propylene-ethylene copolymer elastomer in the second step, is economical and flexible. Excellent in heat resistance, heat resistance and cold resistance. However, the crystalline polypropylene produced in the first step and the propylene-ethylene copolymer elastomer produced in the second step are phase-separated, resulting in a significant drawback that the transparency is remarkably deteriorated.

  As a countermeasure to such a problem, in order not to deteriorate the transparency, a proposal has been made to suppress the ethylene content within a range in which the ethylene-propylene random copolymer produced in the second step does not cause phase separation. (For example, refer to Patent Documents 1 and 2.)

  In the above, a propylene homopolymer or a propylene-ethylene copolymer having a low ethylene content in the first step, and a propylene-ethylene copolymer elastomer having a relatively low ethylene content in the second step, although having a higher ethylene content than the first step, In the method of continuous polymerization using a Ziegler-Natta catalyst, since the Ziegler-Natta catalyst has multiple types of active sites, the crystallinity and molecular weight distribution of the propylene-ethylene copolymer are widened, and the low crystallinity and It produces a lot of low molecular weight components. As a result, when the molded product is stored for a long period of time or at a high temperature, a phenomenon that these low crystallinity and low molecular weight components bleed out to the surface of the molded product occurs, and the commercial value is greatly impaired.

  In order to suppress the generation of low crystallinity and low molecular weight components that cause this bleed out, there is also a method of increasing the intrinsic viscosity of the elastomer, that is, the average molecular weight, to some extent (for example, see Patent Document 3). Due to the wide distribution, even if the average molecular weight is increased, the generation of low crystalline and low molecular weight components cannot be completely suppressed. Therefore, the transparency is not sufficient, and stickiness and bleed out are improved to some extent, although they are somewhat improved. Further, since the average molecular weight of the elastomer is high, an appearance defect called “fish eye” is likely to occur, and the fluidity is lowered, so that the moldability is deteriorated. In order to improve this, it is necessary to control the fluidity with an organic peroxide or the like in the granulation process, but this also has the problem of deteriorating the odor of the molded product and the taste of the contents.

  Also, a propylene resin composition obtained by adding a specific thermoplastic resin to a propylene-ethylene block copolymer obtained by sequentially polymerizing two specific propylene-ethylene random copolymer components using a metallocene catalyst. Although there is a method of molding (for example, see Patent Document 4), a nucleating agent is necessary to obtain transparency, and hygienic deterioration, odor deterioration, molded product by using this nucleating agent. There was concern about bleeding out of the additive on the surface.

JP-A 63-159212 JP 63-168414 A Japanese Patent No. 3358441 JP 2011-98762 A

  An object of the present invention is to solve the above-mentioned problems, to provide a thermoplastic resin composition having high heat resistance and flexibility and having high transparency, and a molded body using the same.

As a result of intensive studies to solve the above-mentioned problems, the present inventor has achieved both flexibility, heat resistance and transparency by using a specific proportion of a thermoplastic elastomer in a specific propylene-ethylene block copolymer. I found out that In particular, thermoplastic elastomers have been conventionally used for imparting flexibility and impact resistance, but they have been found to exhibit transparency when added in small proportions, and have reached the present invention.
The present invention provides the following thermoplastic resin composition and molded product thereof.

[1] 90 to 99.5 parts by weight of propylene-ethylene block copolymer [I] satisfying the following (i) to (v) and thermoplasticity incompatible with propylene-ethylene block copolymer [I] A thermoplastic resin composition comprising 0.5 to 10 parts by weight of elastomer [II] (however, the total of both is 100 parts by weight).
(I) Using a metallocene-based catalyst, 30 to 95 wt% of propylene-ethylene random copolymer component (A) having propylene homopolymer or ethylene content of 7 wt% or less in the first step, and from component (A) in the second step A propylene-ethylene block copolymer obtained by sequential polymerization of 70 to 5 wt% of the propylene-ethylene random copolymer component (B) containing 3 to 20 wt% of ethylene (ii) Melt flow The rate (MFR: 230 ° C., 2.16 kg) is in the range of 0.5 to 100 g / 10 min. (Iii) The melting peak temperature (Tm) measured by the DSC method is in the range of 110 to 150 ° C. (Iv) The molecular weight distribution (Mw / Mn) measured by the GPC method is in the range of 1.5 to 4 (v) obtained by solid viscoelasticity measurement. Temperature - In the loss tangent (tan [delta) curve, the tan [delta curve has a single peak at 0 ℃ below

[2] The thermoplastic resin composition as described in [1] above, wherein the amount of the thermoplastic elastomer [II] is 1 to 5 parts by weight.
[3] The thermoplastic resin composition according to the above [1] or [2], wherein the thermoplastic elastomer [II] is a thermoplastic elastomer composed of ethylene and an α-olefin having 3 to 10 carbon atoms. object.
[4] The thermoplastic resin composition according to [1] or [2], wherein the thermoplastic elastomer [II] is a thermoplastic elastomer composed of ethylene and an α-olefin having 3 to 10 carbon atoms. object.
[5] A molded product formed by molding the thermoplastic resin composition according to any one of [1] to [4].
[6] The molded product according to [5], wherein the molded product is a food storage container.

  The thermoplastic resin composition of the present invention is a resin composition having high flexibility, heat resistance and transparency, and a molded product obtained by molding the thermoplastic resin composition is a storage bottle, food storage container due to its excellent balance of physical properties. , Caps and lids, and seals for various containers.

It is a figure which shows the elution amount and elution amount integration | stacking of the propylene-ethylene random copolymer component (A) and propylene-ethylene random copolymer component (B) by TREF. It is a flow sheet figure of the superposition | polymerization apparatus used by manufacture example 1 of the Example.

The present invention relates to 90 to 99.5 parts by weight of a propylene-ethylene block copolymer [I] satisfying the above (i) to (v), and a thermoplastic elastomer [II] 0. 0 incompatible with [I]. It is a thermoplastic resin composition characterized by comprising 5 to 10 parts by weight (however, the total of both is 100 parts by weight), and is a molded product formed by molding this thermoplastic resin composition.
Hereinafter, components, production methods, and molded articles constituting the thermoplastic resin composition of the present invention will be described in detail.

[1] Propylene-ethylene block copolymer [I]
The propylene-ethylene block copolymer [I] used in the present invention is a propylene-ethylene random copolymer component (A) containing propylene alone or having an ethylene content of 7 wt% or less in the first step using a metallocene catalyst. After the polymerization of 30 to 95 wt%, in the second step, the propylene-ethylene random copolymer component (B) containing 3 to 20 wt% more ethylene than the propylene-ethylene random copolymer component (A) of the first step is added. It is a propylene-ethylene block copolymer obtained by sequential polymerization of 70 to 5 wt%.
The propylene-ethylene block copolymer referred to here is a propylene-ethylene random copolymer component (A) (hereinafter also referred to as component (A)) and a propylene-ethylene random copolymer component (B). (Hereinafter also referred to as “component (B)”) is a block copolymer under a common name obtained by sequential polymerization, and the component (A) and the component (B) are not necessarily combined in a block form. It doesn't have to be a thing.

Conditions (i) to (v) of propylene-ethylene block copolymer [I]
(I) Ethylene content in component / component (A) of propylene-ethylene block copolymer [I]: [E] A
The propylene-ethylene random copolymer component (A) produced in the first step is a component for developing the heat resistance of the propylene-based thermoplastic elastomer composition. Since it is preferable to have crystallinity, it is necessary to be a propylene-ethylene random copolymer having an ethylene content of 7 wt% or less. When the ethylene content exceeds 7 wt%, the flexibility of the propylene-based thermoplastic elastomer composition is improved, but there is a concern that the heat resistance is extremely lowered. The ethylene content is preferably 5 wt% or less, more preferably 3 wt% or less.

-Ethylene content in component (B): [E] B
The propylene-ethylene random copolymer component (B) produced in the second step imparts the flexibility of the propylene-based thermoplastic elastomer composition and increases the affinity with the thermoplastic elastomer used in combination, and makes the molded article transparent. It is a component for expressing a feeling. In order to increase the flexibility of the propylene-based thermoplastic elastomer composition, [E] B is preferably as high as possible. However, if it is too high, component (A) and component (B) in the propylene-ethylene block copolymer are too high. ), And as a result, the entire composition does not become a uniform and fine dispersion, which is not preferable because mechanical properties, transparency, and the like are greatly reduced.

In order to deal with such problems, the range of the ethylene content of component (B) is the difference from the ethylene content of component (A) [E] B- [E] A (hereinafter also referred to as [E] gap). It is prescribed by. [E] B- [E] A needs to be in the range of 3 to 20 wt%, preferably 6 to 18 wt%, more preferably 8 to 16 wt%.
[E] If the gap exceeds 20 wt%, the compatibility with the component (A) produced in the first step is deteriorated, and the entire composition becomes a non-uniform dispersion, resulting in impact resistance and tensile strength. It is not preferable because mechanical properties such as elongation are significantly lowered and transparency is also deteriorated.

-Ratio of component (A): W (A) and ratio of component (B): W (B)
The proportion of the content of W (A) that is the proportion of component (A) and the proportion of component (B) that constitute propylene-ethylene block copolymer [I] is that W (A) is 30 to 95 wt% and W (B) needs to be in the range of 70 to 5 wt%.
When the proportion of W (A) is less than 30 wt%, the thermoplastic elastomer described below can provide flexibility with a small proportion, but it cannot be used at high temperatures due to the lack of components that maintain heat resistance. It becomes. On the other hand, if the ratio of W (A) exceeds 95 wt%, a thermoplastic elastomer must be used at a high ratio in order to obtain flexibility, resulting in a decrease in heat resistance. Preferably, the ratio of W (A) is in the range of 40 to 80 wt%, more preferably 50 to 70 wt%.

・ Specification of [E] A and [E] B and each component amount W (A) and W (B) Each ethylene content and amount of component (A) and (B) is the material balance at the time of manufacture (material balance) However, in order to specify these more accurately, it is desirable to use the following analysis.

..Specification of each component amount W (A) and W (B) by temperature rising elution fractionation (TREF) The technique for evaluating the crystallinity distribution of propylene-ethylene random copolymer by TREF is well known to those skilled in the art. For example, detailed measurement methods are shown in the following documents.
G. Glockner, J. et al. Appl. Polym. Sci. : Appl. Polym. Symp. 45, 1-24 (1990)
L. Wild, Adv. Polym. Sci. 98, 1-47 (1990)
J. et al. B. P. Soares, A .; E. Hamielec, Polymer; 36, 8, 1639-1654 (1995)

The propylene-ethylene block copolymer [I] in the present invention is greatly different in the crystallinity of each of the components (A) and (B), and each crystallinity distribution is produced by being produced using a metallocene catalyst. Therefore, the intermediate component between the two is extremely small, and it is possible to determine both with high accuracy by TREF.
A specific method will be described with reference to the figure showing the elution amount and the elution amount integration by TREF in FIG.
In the TREF elution curve (plot of elution amount versus temperature), components (A) and (B) show their elution peaks at T (A) and T (B), respectively, due to the difference in crystallinity, and the difference is sufficiently large. Separation is possible at an intermediate temperature T (C) (= {T (A) + T (B)} / 2).

In addition, the lower limit of the TREF measurement temperature is −15 ° C. in the apparatus used for this measurement, but in the case where the crystallinity of the component (B) is very low or an amorphous component, There may be no peak in the range. In this case, the concentration of the component (B) dissolved in the solvent at the measurement temperature lower limit (that is, −15 ° C.) is detected.
At this time, T (B) is considered to exist below the lower limit of the measurement temperature, but the value cannot be measured. In such a case, T (B) is the lower limit of the measurement temperature. Defined as ° C.
Here, if the integrated amount of the component eluted before T (C) is defined as W (B) wt%, and the integrated amount of the component eluted at T (C) or higher is defined as W (A) wt%, W (B) Almost corresponds to the amount of the component (B) having low crystallinity or amorphousness, and the integrated amount W (A) of the component eluted at T (C) or higher is the component (A) having relatively high crystallinity. Almost corresponds to the amount of. The elution amount curve obtained by TREF and the above-described methods for calculating the various temperatures and amounts obtained therefrom are performed as illustrated in FIG.

.. TREF Measuring Method In the present invention, the TREF is specifically measured as follows.
A sample is dissolved in o-dichlorobenzene (containing 0.5 mg / mL BHT) at 140 ° C. to obtain a solution. This is introduced into a 140 ° C. TREF column, cooled to 100 ° C. at a rate of 8 ° C./min, subsequently cooled to −15 ° C. at a rate of 4 ° C./min, and held for 60 minutes. Thereafter, o-dichlorobenzene (containing 0.5 mg / mL BHT) as a solvent is flowed through the column at a flow rate of 1 mL / min, and components dissolved in o-dichlorobenzene at −15 ° C. are eluted in the TREF column for 10 minutes. Next, the column is linearly heated to 140 ° C. at a heating rate of 100 ° C./hour to obtain an elution curve.

... Specification of ethylene content [E] A and [E] B in each component ... Separation of component (A) and component (B) Based on T (C) determined by TREF measurement at the previous point, Using a preparative type fractionation device, the soluble component (B) in T (C) and the insoluble component (A) in T (C) are separated by a temperature rising column separation method, and the ethylene content of each component is determined by NMR. Ask.
The temperature rising column fractionation method refers to a measurement method disclosed in, for example, Macromolecules, 21 314 to 319 (1988). Specifically, the following method was used in the present invention.

··· Separation conditions A cylindrical column having a diameter of 50 mm and a height of 500 mm is filled with a glass bead carrier (80 to 100 mesh) and maintained at 140 ° C. Next, 200 mL of the o-dichlorobenzene solution (10 mg / mL) of the sample dissolved at 140 ° C. is introduced into the column. Thereafter, the temperature of the column is cooled to 0 ° C. at a rate of temperature decrease of 10 ° C./hour. After holding at 0 ° C. for 1 hour, the column temperature is heated to T (C) at a heating rate of 10 ° C./hour and held for 1 hour. Note that the temperature control accuracy of the column through a series of operations is ± 1 ° C.
Next, while maintaining the column temperature at T (C), 800 mL of o (dichlorobenzene) of T (C) is allowed to flow at a flow rate of 20 mL / min, whereby components soluble in T (C) existing in the column are obtained. Elute and collect.
Next, the column temperature is increased to 140 ° C. at a temperature rising rate of 10 ° C./min, and after leaving still at 140 ° C. for 1 hour, by flowing 800 mL of a 140 ° C. solvent (o-dichlorobenzene) at a flow rate of 20 mL / min, Elute insoluble components with T (C) and collect.
The solution containing the polymer obtained by fractionation is concentrated to 20 mL using an evaporator and then precipitated in 5 times the amount of methanol. The precipitated polymer is recovered by filtration and then dried overnight in a vacuum dryer.

· · ¹³ C-NMR according to the measurement the fractionated by components obtained ethylene content (A) (B) an ethylene content of each is, ¹³ C-NMR spectrum measured under the following conditions by complete proton decoupling method It is obtained by analyzing.
Model: GSX-400 manufactured by JEOL Ltd. or equivalent equipment (carbon nuclear resonance frequency of 100 MHz or more)
Solvent: o-dichlorobenzene / heavy benzene = 4/1 (volume ratio)
Concentration: 100 mg / mL
Temperature: 130 ° C
Pulse angle: 90 °
Pulse interval: 15 seconds Integration count: 5,000 times or more

The spectrum may be assigned with reference to Macromolecules, 17 1950 (1984), for example. The attribution of spectra measured under the above conditions is as shown in the table below. In the table, symbols such as S _αα are in accordance with the notation of Carman et al. (Macromolecules, 10536 (1977)), P represents a methyl carbon, S represents a methylene carbon, and T represents a methine carbon.

Hereinafter, when “P” is a propylene unit in a copolymer chain and “E” is an ethylene unit, six kinds of triads of PPP, PPE, EPE, PEP, PEE, and EEE may exist in the chain. As described in Macromolecules, 15 1150 (1982), the concentration of these triads and the peak intensity of the spectrum are linked by the following relational expressions (1) to (6).
[PPP] = k × I (T _ββ ) (1)
[PPE] = k × I (T _βδ ) (2)
[EPE] = k × I (T _δδ ) (3)
[PEP] = k × I (S _ββ ) (4)
[PEE] = k × I (S _βδ ) (5)
[EEE] = k × [I (S _δδ ) / 2 + I (S _γδ ) / 4} (6)
Here, [] indicates the fraction of triads, for example, [PPP] is the fraction of PPP triads in all triads. Therefore,
[PPP] + [PPE] + [EPE] + [PEP] + [PEE] + [EEE] = 1 (7). Further, k is a constant, I indicates the spectral intensity, and for example, I (T _ββ ) means the intensity of the peak at 28.7 ppm attributed to T _ββ .

By using the relational expressions (1) to (7) above, the fraction of each triad is obtained, and the ethylene content is obtained from the following expression.
Ethylene content (mol%) = ([PEP] + [PEE] + [EEE]) × 100
In addition, the propylene random copolymer of the present invention contains a small amount of a propylene hetero bond (2,1-bond and / or 1,3-bond), thereby producing the following minute peak.

In order to obtain an accurate ethylene content, it is necessary to include these peaks derived from heterogeneous bonds in the calculation, but it is difficult to completely separate and identify the peaks derived from heterogeneous bonds, and the amount of heterogeneous bonds is small. Therefore, the ethylene content of the present invention is determined using the relational expressions (1) to (7) as in the analysis of the copolymer produced with the Ziegler catalyst that does not substantially contain heterogeneous bonds. .
Conversion from mol% to wt% of ethylene content is performed using the following formula.
Ethylene content (wt%) =
(28 * X / 100) / {28 * X / 100 + 42 * (1-X / 100)} * 100
Here, X is the ethylene content in mol%.
Further, the ethylene content [E] W of the entire propylene-ethylene block copolymer is calculated from the ethylene contents [E] A, [E] B and TREF of the components (A) and (B) measured from the above. From the weight ratio W (A) and W (B) wt% of each component, the following formula is used.
[E] W = {[E] A × W (A) + [E] B × W (B)} / 100 (wt%)

(Ii) Melt flow rate (MFR)
The melt flow rate (MFR) of the propylene-ethylene block copolymer [I] used in the present invention is 0.5 to 100 g / 10 minutes, preferably 1 to 50 g / 10 minutes, more preferably 2 to 2. 35 g / 10 min. If the MFR is less than 0.5 g / 10 min, molding becomes difficult, and if it exceeds 100 g / 10 min, impact resistance cannot be expected.
The melt flow rate (MFR) can be easily adjusted by adjusting the temperature and pressure, which are the polymerization conditions of the propylene-ethylene block copolymer, or by controlling the amount of hydrogen added during polymerization of a chain transfer agent such as hydrogen. Can be done.
Here, MFR is a value measured at a heating temperature of 230 ° C. and a load of 21.2 N in accordance with JIS K7210.

(Iii) Melting peak temperature (Tm)
The melting peak temperature (Tm) measured by the differential scanning calorimeter (DSC) of the propylene-ethylene block copolymer [I] used in the present invention needs to be in the range of 110 to 150 ° C. It is preferable that it is 140 degreeC. When Tm is less than 110 ° C., the rate at which the composition cools and solidifies from the molten state is delayed, and the moldability may be deteriorated. On the other hand, if the temperature exceeds 150 ° C., the impact resistance improvement effect may be reduced, which is not preferable. The Tm can be adjusted easily by controlling the amount of ethylene supplied to the polymerization reaction system.
Here, the specific measurement of Tm is performed using a differential scanning calorimeter (DSC), taking a sample amount of 5 mg, holding at 200 ° C. for 5 minutes, and then crystallizing to 40 ° C. at a rate of temperature decrease of 10 ° C./min. Further, the peak position of the curve drawn when the film is melted at a temperature rising rate of 10 ° C./min is defined as a melting peak temperature Tm (° C.).

(Iv) Molecular weight distribution (Mw / Mn)
The molecular weight distribution (Mw / Mn) measured by the gel permeation (GPC) method of the propylene-ethylene block copolymer [I] used in the present invention needs to be in the range of 1.5 to 4, It is preferably 1.8 or more and less than 3. If Mw / Mn is less than 1.5, it is difficult to obtain with the current polymerization technique, and if it exceeds 4, the product (pellet) may become sticky.
When narrowing the molecular weight distribution of the propylene-ethylene block copolymer, use a metallocene-based catalyst, which will be described later, or polymerize the propylene-ethylene block copolymer and then melt knead using an organic peroxide. It can be adjusted by doing. When making it wide, it can adjust by superposing | polymerizing using the catalyst system which used together 2 or more types of metallocene catalyst components, or the catalyst system which used 2 or more types of metallocene complexes together.

Here, the molecular weight distribution is obtained by the ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn), and is obtained by measurement by a gel permeation chromatography (GPC) method.
Conversion from the retention volume to the molecular weight is performed using a calibration curve prepared in advance with standard polystyrene.
The standard polystyrenes used are all the following brands manufactured by Tosoh Corporation.
F380, F288, F128, F80, F40, F20, F10, F4, F1, A5000, A2500, A1000
A calibration curve is prepared by injecting 0.2 ml of a solution dissolved in o-dichlorobenzene (containing 0.5 mg / ml BHT) so that each is 0.5 mg / ml.
The calibration curve uses a cubic equation obtained by approximation by the least square method. The following numerical value is used for [η] = K × M ^α in the viscosity formula used for conversion to molecular weight.
PS: K = 1.38 × 10 ⁻⁴ α = 0.7
PP: K = 1.03 × 10 ⁻⁴ α = 0.78

The measurement conditions for GPC are as follows.
Apparatus: GPC (ALC / GPC 150C) manufactured by WATERS
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 Measurement temperature: 140 ° C
Flow rate: 1.0 ml / min Injection volume: 0.2 ml
Sample preparation: Prepare a 1 mg / ml solution using o-dichlorobenzene (containing 0.5 mg / ml BHT) and dissolve it at 140 ° C. for about 1 hour.

(V) Definition by peak of tan δ curve In the present invention, component (A) and component (B) constituting propylene-ethylene block copolymer [I] are not phase-separated in order to obtain transparency. Is extremely necessary. The phase separation conditions are affected not only by the ethylene content but also by the molecular weight and composition. Therefore, in addition to the above-mentioned regulations regarding the ethylene content, a temperature-loss tangent (tan δ) curve obtained by solid viscoelasticity measurement (DMA) Therefore, it is necessary to define the peak of the tan δ curve.
When the propylene-ethylene block copolymer has a phase separation structure, the glass transition temperature of the amorphous part contained in the component (A) is different from the glass transition temperature of the amorphous part contained in the component (B). , There will be multiple peaks. Conversely, when they are compatible, both components are mixed in the order of molecules and have a single peak at a temperature intermediate between the glass transition temperatures of both components. That is, whether or not the phase separation structure is taken can be determined in the temperature-tan δ curve in the solid viscoelasticity measurement, and in order to maintain transparency, the tan δ curve has a single peak at 0 ° C. or lower. is necessary.

  Specifically, solid viscoelasticity measurement is performed by applying a sinusoidal strain of a specific frequency to a strip-shaped sample piece and detecting the generated stress. Here, the frequency is 1 Hz and the measurement temperature is raised stepwise from −60 ° C. until the sample is melted and cannot be measured. Further, it is recommended that the magnitude of distortion is about 0.1 to 0.5%. From the obtained stress, the storage elastic modulus G ′ and the loss elastic modulus G ″ are obtained by a known method, and the loss tangent (= loss elastic modulus / storage elastic modulus) defined by the ratio is plotted against the temperature. Then, a sharp peak is shown in a temperature range of 0 ° C. or lower. Generally, the peak of the tan δ curve at 0 ° C. or lower is for observing the glass transition of the amorphous part, and here, this peak temperature is defined as the glass transition temperature Tg (° C.).

[3] Method for Producing Propylene-Ethylene Block Copolymer The method for producing propylene-ethylene block copolymer [I] used in the present invention requires the use of a metallocene catalyst.

Metallocene-based catalyst The type of metallocene-based catalyst is not particularly limited as long as it can produce a copolymer having the performance of the present invention, but in order to satisfy the requirements of the present invention, for example, the following is shown: It is preferable to use a metallocene catalyst composed of such catalyst components (a) and (b) and a catalyst component (c) used as necessary.
Component (a): At least one metallocene transition metal compound selected from transition metal compounds represented by the following general formula Component (b): At least one selected from the following (b-1) to (b-4) (B-1) a particulate carrier on which an organoaluminoxy compound is supported,
(B-2) Particulate carrier carrying an ionic compound or Lewis acid capable of reacting with component (a) to convert component (a) into a cation (b-3) Solid acid fine particles (b- 4) Ion exchange layered silicate Component (c): Organoaluminum compound

..Catalyst component (a)
As the component (a), at least one metallocene transition metal compound selected from transition metal compounds represented by the following general formula can be used.
^{_{Q (C 5 H 4-a}} R 1) (C 5 H 4-b R 2) MeXY
[Wherein Q represents a divalent linking group that bridges two conjugated five-membered ring ligands, Me represents a metal atom selected from titanium, zirconium, and hafnium, and X and Y represent a hydrogen atom, a halogen atom, An atom, a hydrocarbon group, an alkoxy group, an amino group, a nitrogen-containing hydrocarbon group, a phosphorus-containing hydrocarbon group or a silicon-containing hydrocarbon group is shown, and X and Y may be the same or different from each other. R ¹ and R ² are hydrogen, hydrocarbon group, halogenated hydrocarbon group, silicon-containing hydrocarbon group, nitrogen-containing hydrocarbon group, oxygen-containing hydrocarbon group, boron-containing hydrocarbon group, or phosphorus-containing hydrocarbon group. Show. a and b are the number of substituents. ]

Specifically, Q represents a divalent linking group that bridges two conjugated five-membered ring ligands, and has, for example, a divalent hydrocarbon group, a silylene group, an oligosilylene group, or a hydrocarbon group as a substituent. Examples include a silylene group, an oligosilylene group, or a germylene group having a hydrocarbon group as a substituent. Among these, preferred is a silylene group having a divalent hydrocarbon group and a hydrocarbon group as a substituent.
X and Y represent a hydrogen atom, a halogen atom, a hydrocarbon group, an alkoxy group, an amino group, a nitrogen-containing hydrocarbon group, a phosphorus-containing hydrocarbon group, or a silicon-containing hydrocarbon group. Among these, hydrogen is preferable , Chlorine, methyl, isobutyl, phenyl, dimethylamide, diethylamide group and the like. X and Y may be independent, that is, may be the same or different.

R ¹ and R ² are hydrogen, hydrocarbon group, halogenated hydrocarbon group, silicon-containing hydrocarbon group, nitrogen-containing hydrocarbon group, oxygen-containing hydrocarbon group, boron-containing hydrocarbon group, or phosphorus-containing hydrocarbon group. Represents. Specific examples of the hydrocarbon group include a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group, a phenyl group, a naphthyl group, a butenyl group, and a butadienyl group. In addition, as halogenated hydrocarbon group, silicon-containing hydrocarbon group, nitrogen-containing hydrocarbon group, oxygen-containing hydrocarbon group, boron-containing hydrocarbon group, or phosphorus-containing hydrocarbon group, methoxy group, ethoxy group, phenoxy group Typical examples include trimethylsilyl group, diethylamino group, diphenylamino group, pyrazolyl group, indolyl group, dimethylphosphino group, diphenylphosphino group, diphenylboron group, and dimethoxyboron group. Among these, a hydrocarbon group having 1 to 20 carbon atoms is preferable, and a methyl group, an ethyl group, a propyl group, and a butyl group are particularly preferable. By the way, adjacent R ¹ and R ² may combine to form a ring, on which a hydrocarbon group, halogenated hydrocarbon group, silicon-containing hydrocarbon group, nitrogen-containing hydrocarbon group, oxygen-containing You may have a substituent which consists of a hydrocarbon group, a boron containing hydrocarbon group, or a phosphorus containing hydrocarbon group.
Me is a metal atom selected from titanium, zirconium and hafnium, preferably zirconium and hafnium.

  Among the components (a) described above, those preferred for the production of the propylene-ethylene random block copolymer [I] used in the present invention are a silylene group, a germylene group or an alkylene group having a hydrocarbon substituent. It is a transition metal compound comprising a ligand having a bridged substituted cyclopentadienyl group, substituted indenyl group, substituted fluorenyl group, substituted azulenyl group, particularly preferably a silylene group having a hydrocarbon substituent or a germylene group It is a transition metal compound comprising a ligand having a 2,4-position-substituted indenyl group and a 2,4-position-substituted azulenyl group which are cross-linked by

Non-limiting specific examples include dimethylsilylene bis (2-methyl-4-phenylindenyl) zirconium dichloride, diphenylsilylene bis (2-methyl-4-phenylindenyl) zirconium dichloride, dimethylsilylene bis (2-methyl). Benzoindenyl) zirconium dichloride, dimethylsilylene bis {2-isopropyl-4- (3,5-diisopropylphenyl) indenyl} zirconium dichloride, dimethylsilylene bis (2-propyl-4-phenanthrylindenyl) zirconium dichloride, dimethyl Silylene bis (2-methyl-4-phenylazurenyl) zirconium dichloride, dimethylsilylene bis {2-methyl-4- (4-chlorophenyl) azurenyl} zirconium dichloride, dimethylsilylene bi (2-Ethyl-4-phenylazurenyl) zirconium dichloride, dimethylsilylenebis (2-isopropyl-4-phenylazurenyl) zirconium dichloride, dimethylsilylenebis {2-ethyl-4- (2-fluorobiphenyl) azurenyl} zirconium Dichloride, dimethylsilylenebis {2-ethyl-4- (4-t-butyl-3-chlorophenyl) azurenyl} zirconium dichloride, and the like can be given. A compound in which the silylene group of these specific examples is replaced with a germylene group and zirconium is replaced with hafnium is also exemplified as a suitable compound.
In addition, since the catalyst component is not an important element of the present invention, it avoids complicated listing and is limited to a representative example, but it is obvious that the effective range of the present invention is not limited thereby. It is.

..Catalyst component (b)
As the component (b), at least one solid component selected from the components (b-1) to (b-4) described above is used. Each of these components is a known component, and can be appropriately selected from known technologies and used. Specific examples and manufacturing methods thereof are described in detail in JP-A No. 2002-284808, JP-A No. 2002-53609, JP-A No. 2002-69116, JP-A No. 2003-105015, and the like.
Here, as the particulate carrier used for the component (b-1) and the component (b-2), inorganic oxides such as silica, alumina, magnesia, silica alumina, silica magnesia, magnesium chloride, magnesium oxychloride, chloride Examples thereof include inorganic halides such as aluminum and lanthanum chloride, and porous organic carriers such as polypropylene, polyethylene, polystyrene, styrene divinyl benzene copolymer, and acrylic acid copolymer.

Further, as a non-limiting specific example of the component (b), as the component (b-1), a particulate carrier on which methylalumoxane, isobutylalumoxane, methylisobutylalumoxane, aluminum butylboronate tetraisobutyl and the like are supported As component (b-2), triphenylborane, tris (3,5-difluorophenyl) borane, tris (pentafluorophenyl) borane, triphenylcarbonium tetrakis (pentafluorophenyl) borate, N, N-dimethyl Particulate carrier carrying anilinium tetrakis (pentafluorophenyl) borate, etc., component (b-3), alumina, silica alumina, magnesium chloride, etc., component (b-4), montmorillonite, zakonite, beidellite , Nontronic , Saponite, hectorite, stevensite, bentonite, smectite group such as taeniolite, vermiculite, and the like mica group. These may form a mixed layer.
Particularly preferred among the above components (b) is the ion-exchange layered silicate of component (b-4), and more preferred are chemical treatments such as acid treatment, alkali treatment, salt treatment, and organic matter treatment. It is an ion exchange layered silicate applied.

..Catalyst component (c)
Examples of organoaluminum compounds used as component (c) as needed are:
General formula: AlR _a P _3-a
(Wherein R is a hydrocarbon group having 1 to 20 carbon atoms, P is hydrogen, halogen, alkoxy group, a is a number of 0 <a ≦ 3), trimethylaluminum, triethylaluminum, tripropylaluminum, tri Trialkylaluminum such as isobutylaluminum or halogen or alkoxy-containing alkylaluminum such as diethylaluminum monochloride, diethylaluminum monomethoxide.
In addition, aluminoxanes such as methylaluminoxane can also be used. Of these, trialkylaluminum is particularly preferable.

.. Formation of catalyst The catalyst component (a) is contacted with the component (b) and, if necessary, the component (c) to form a catalyst. The contact method is not particularly limited, but the contact can be made in the following order. Moreover, this contact may be performed not only at the time of catalyst preparation but also at the time of prepolymerization with olefin or at the time of polymerization of olefin.
1) Contact component (a) and component (b) 2) Add component (c) after contacting component (a) and component (b) 3) Contact component (a) and component (c) 4) Add component (a) after contacting component (b) and component (c). Alternatively, the other three components may be contacted simultaneously.

The used amount of the catalyst components (a), (b) and (c) to be used is arbitrary. For example, the amount of component (a) used relative to component (b) is preferably in the range of 0.1 μmol to 1,000 μmol, particularly preferably 0.5 μmol to 500 μmol, relative to 1 g of component (b). The amount of component (c) used relative to component (b) is preferably such that the amount of transition metal is 0.001 to 100 μmol, particularly preferably 0.005 to 50 μmol, relative to 1 g of component (b). Therefore, the amount of the component (c) to the component (a) is preferably in the range of 10 ⁻⁵ to 50, particularly preferably 10 ^{−4 to} 5 in terms of the molar ratio of the transition metal.

It is preferable that the catalyst used in the production of the propylene-ethylene block copolymer is subjected to a prepolymerization treatment comprising previously contacting an olefin and polymerizing a small amount.
The olefin used for the prepolymerization is not particularly limited, but ethylene, propylene, 1-butene, 1-hexene, 1-octene, 4-methyl-1-pentene, 3-methyl-1-butene, vinylcycloalkane, Styrene and the like can be used, and it is particularly preferable to use propylene. The olefin can be supplied by any method, such as a supply 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. The amount of prepolymerization is preferably 0.01 to 100, more preferably 0.1 to 50 with respect to the component (b). After completion of the prepolymerization, the catalyst can be used as it is, depending on the usage form of the catalyst. However, if necessary, drying can be performed.
Furthermore, a polymer such as polyethylene, polypropylene, or polystyrene, or an inorganic oxide solid such as silica or titania can be allowed to coexist during or after the contact of the above components.

-Polymerization method-Sequential polymerization In order to produce propylene-ethylene block copolymer [I], it is necessary to polymerize component (A) and component (B) sequentially. In the conventional propylene-ethylene copolymer, there is no well-considered balance of the propylene-ethylene copolymer obtained in the first step and the second step, and the flexibility, impact resistance and transparency are improved in a well-balanced manner. There was nothing to let me.
Therefore, in the present invention, the propylene-ethylene block copolymer is a block copolymer obtained by sequentially polymerizing components having different ethylene contents in the first step and the second step. Necessary to balance all heat resistance.
In the present invention, since a copolymer having a low molecular weight and easily sticking alone may be used as the component (B), the component (A) is polymerized in order to prevent problems such as adhesion to the reactor. It is necessary to use a method of polymerizing component (B).
When performing sequential polymerization, either a batch method or a continuous method can be used, but it is generally desirable to use a continuous method from the viewpoint of productivity.

In the case of a batch method, it is possible to polymerize component (A) and component (B) separately using a single reactor by changing the polymerization conditions with time. As long as the effects of the present invention are not impaired, a plurality of reactors may be connected in parallel.
In the case of a continuous process, it is necessary to use a production facility in which two or more reactors are connected in series because it is necessary to individually polymerize the component (A) and the component (B), but the effect of the present invention is not impaired. As long as each of the component (A) and the component (B) is used, a plurality of reactors may be connected in series and / or in parallel.

..Polymerization process As the polymerization process, an arbitrary polymerization method such as a slurry method, a bulk method, or a gas phase method can be used. Although supercritical conditions can be used as intermediate conditions between the bulk method and the gas phase method, they are substantially the same as the gas phase method, and are therefore included in the gas phase method without particular distinction.
Since component (B) is readily soluble in organic solvents such as hydrocarbons and liquefied propylene, it is desirable to use a gas phase method for the production of component (B).
The production of component (A) is not particularly problematic regardless of which process is used, but when producing component (A) having relatively low crystallinity, a vapor phase method is used to avoid problems such as adhesion. It is desirable.
Therefore, it is most desirable to polymerize component (A) first by the bulk method or gas phase method and then polymerize component (B) by the gas phase method using the continuous method.

.. Other polymerization conditions The polymerization temperature can be applied without any particular problem as long as it is in a normally used temperature range. Specifically, a range of 0 ° C. to 200 ° C., more preferably 40 ° C. to 100 ° C. can be used.
The polymerization pressure varies depending on the process to be selected, but can be used without any problem as long as it is in a pressure range usually used. Specifically, a range of greater than 0 to 200 MPa, more preferably 0.1 MPa to 50 MPa can be used. At this time, an inert gas such as nitrogen may coexist.
When the sequential polymerization of the component (A) in the first step and the component (B) in the second step is performed, it is desirable to add a polymerization inhibitor into the system in the second step. In the case of producing a propylene-ethylene block copolymer, if a polymerization inhibitor is added to the reactor for carrying out the ethylene-propylene random copolymerization in the second step, the particle properties (fluidity, etc.) of the resulting powder, gel, etc. Product quality can be improved. Various methods have been proposed for this method, and examples include JP-B-63-54296, JP-A-7-25960, JP-A-2003-2939, and the like. desirable.

[4] Method for Controlling Components of Propylene-Ethylene Block Copolymer [I] Each component of propylene-ethylene block copolymer [I] used in the present invention is controlled as follows. It can be manufactured to meet the structural requirements required for coalescence.
・ Ingredient (A)
For component (A), it is necessary to control the ethylene content [E] A and the elution peak temperature T (A).
In the present invention, in order to control [E] A within a predetermined range, the amount ratio of propylene and ethylene supplied to the polymerization tank in the first step may be appropriately adjusted. The relationship between the supply ratio and the ethylene content in the resulting propylene-ethylene random copolymer varies depending on the type of metallocene catalyst used, but the component (A) having the ethylene content [E] A required by adjusting the supply ratio is selected. Can be manufactured.
For example, when [E] A is controlled to be less than 7 wt%, the supply weight ratio of ethylene to propylene may be in the range of 0.3 or less, preferably in the range of 0.2 or less.
At this time, the component (A) has a narrow crystallinity distribution, and T (A) decreases as [E] A increases. Therefore, in order for T (A) to satisfy the scope of the present invention, [E] A and their relationship are grasped and adjusted so as to take a target range.

・ Ingredient (B)
For component (B), it is necessary to control ethylene content [E] B and elution peak temperature T (B).
In the present invention, in order to control [E] B within a predetermined range, the ratio of ethylene supply to propylene in the second step may be controlled as in [E] A. For example, when [E] B is controlled to 3 to 27 wt%, the supply weight ratio of ethylene to propylene may be in the range of 0.005 to 6, preferably in the range of 0.01 to 3.
At this time, although the crystallinity distribution of the component (B) is slightly increased with the increase of the ethylene content, T (B) is decreased with the increase of [E] B, similarly to the component (A). Therefore, in order to satisfy T (B) within the scope of the present invention, the relationship between [E] B and T (B) is grasped, and [E] B is controlled to be within a predetermined range. That's fine.

・ W (A) and W (B)
The amount W (A) of the component (A) and the amount W (B) of the component (B) change the ratio of the production amount of the first step for producing the component (A) and the production amount of the component (B). Can be controlled. For example, in order to increase W (A) and decrease W (B), it is only necessary to reduce the production amount of the second step while maintaining the production amount of the first step, which shortens the residence time of the second step. It can be easily controlled by lowering the polymerization temperature or increasing the amount of the polymerization inhibitor. The reverse is also true.
When actually setting the conditions, it is necessary to consider the activity decay. That is, in the range of the ethylene content [E] A and [E] B carried out in the present invention, generally, when the ratio of ethylene supply to propylene is increased in order to increase the ethylene content, the polymerization activity increases. The activity decay tends to increase. Therefore, in order to maintain the activity of the second step, it is necessary to suppress the polymerization activity of the first step. Specifically, in the first step, the ethylene content [E] A is lowered and the production amount W (A ), And if necessary, lower the polymerization temperature and / or shorten the polymerization time (residence time), or increase the ethylene content [E] B in the second step and increase the production W (B). If necessary, the conditions may be set by a method that raises the polymerization temperature and / or lengthens the polymerization time (residence time).

Single peak of tan δ curve The propylene-ethylene block copolymer used in the present invention has a glass transition temperature Tg that is a temperature at which the tan δ curve obtained in the temperature-loss tangent curve obtained by solid viscoelasticity measurement shows a peak. It is necessary to have a single peak below 0 ° C. In order for Tg to have a single peak, the difference between the ethylene content [E] A in component (A) and the ethylene content [E] B in component (B) [E] gap (= [E ] B- [E] A) may be 20 wt% or less, preferably 16 wt% or less, and [E] gap may be reduced to a range where Tg becomes a single peak in actual measurement.
According to the ethylene content [E] A in the component (A), the supply amount of ethylene to propylene during the polymerization of the component (B) so that the ethylene content [E] B in the component (B) falls within an appropriate range. By setting the ratio, a propylene-ethylene block copolymer having a predetermined [E] gap can be obtained.

Moreover, Tg of the propylene-ethylene block copolymer which does not take a phase-separation structure used for this invention is ethylene content [E] A in a component (A), and ethylene content in a component (B) [ E] It is influenced by the quantity ratio of B and both components. In the present invention, the amount of the component (B) is 5 to 70 wt%, but in this range, Tg is more strongly affected by the ethylene content [E] B in the component (B).
That is, Tg reflects the glass transition of the amorphous part, but in the propylene-ethylene block copolymer used in the present invention, the component (A) has crystallinity and relatively few amorphous parts. On the other hand, the component (B) is low crystalline or amorphous and most of it is an amorphous part. Therefore, the value of Tg is almost controlled by [E] B, and the control method of [E] B is as described above.

[5] Incompatible thermoplastic elastomer [II]
The thermoplastic elastomer [II] used in the present invention must be incompatible with the propylene-ethylene block copolymer [I]. When [I] and [II] are compatible, the crystallinity of [I] is lowered, so that the flexibility is increased but the heat resistance is lowered, and there is a concern of deformation during use at high temperatures. Moreover, the transparency improvement effect cannot be sufficiently obtained.

  As the incompatible thermoplastic elastomer [II], various polymers, copolymers, and elastomers include various thermoplastic elastomers, specifically, known thermoplastic ethylene-based elastomers and thermoplastic styrene-based elastomers. Can be used. Specifically, ethylene-butene copolymer elastomer, ethylene-hexene copolymer elastomer, ethylene-octene copolymer elastomer, ethylene-propylene copolymer elastomer, ethylene-vinyl acetate copolymer, ethylene-acrylate copolymer , Ethylene-acrylonitrile copolymer, ethylene-propylene-diene copolymer elastomer, propylene-ethylene copolymer elastomer, propylene-octene copolymer elastomer (or plastomer), styrene / butadiene / styrene triblock (SBS), Hydrogenated styrene / butadiene / styrene triblock (SEBS), styrene / isoprene / styrene triblock (SIS), hydrogenated styrene / isoprene / styrene triblock (S) PS) styrenic elastomers such as natural rubber, diene rubber, chloroprene rubber, nitrile rubber, such as polysaccharides, natural resins, various elastomers or plastomers and the like.

Among these, a thermoplastic elastomer composed of ethylene and an α-olefin having 3 to 10 carbon atoms is preferable, and an ethylene-hexene copolymer elastomer and an ethylene-octene copolymer elastomer are particularly preferable.
The density of the copolymer elastomer of ethylene and an α-olefin having 4 to 10 carbon atoms is preferably in the range of 0.860 to 0.910 g / cm ³ , and is particularly preferably a copolymer produced using a metallocene catalyst. Polymers are preferred.

  The melt flow rate (190 ° C., 2.16 kg) of the thermoplastic elastomer (II) is preferably 0.1 to 100 g / 10 minutes, more preferably 0.5 to 60 g / 10 minutes, and still more preferably. 1-30 g / 10 min.

  The thermoplastic elastomer (II) can be used alone or in combination of two or more.

The blending ratio of the propylene-ethylene block copolymer (I) and the thermoplastic elastomer (II) is 100 parts by weight of the total amount of (I) and (II), and the propylene-ethylene block copolymer [I] 90 to 99.5 parts by weight and 0.5 to 10 parts by weight of the thermoplastic elastomer [II]. The thermoplastic elastomer [II] is preferably 1 to 10 parts by weight, more preferably 1 to 8 parts by weight, and still more preferably 1 to 6 parts by weight.
When the thermoplastic elastomer (II) exceeds 10 parts by weight, the heat distortion resistance and transparency are lowered although the flexibility is high. On the other hand, when the amount is less than 0.5 parts by weight, problems such as insufficient improvement of transparency occur.

[6] Additives In the present invention, additives such as various antioxidants, nucleating agents, neutralizing agents, lubricants, ultraviolet absorbers, light stabilizers and the like used as stabilizers for propylene polymers are added. Can be blended. However, depending on the additive used, there is a possibility of non-compliance with the application in the food, medical field, etc., so it is necessary to select according to the intended use.

  Specifically, as the antioxidant, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol-di-phosphite, di-stearyl-pentaerythritol-di-phosphite, bis ( 2,4-di-t-butylphenyl) pentaerythritol-diphosphite, tris (2,4-di-t-butylphenyl) phosphite, tetrakis (2,4-di-t-butylphenyl) -4 Phosphorous antioxidants such as 4,4'-biphenylene-diphosphonite, tetrakis (2,4-di-t-butyl-5-methylphenyl) -4,4'-biphenylene-diphosphonite, 2,6-di-t-butyl-p-cresol, tetrakis [methylene (3,5-di-t-butyl-4-hydroxyhydrocinnamate)] methane, 1 3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate Phenolic antioxidants such as di-stearyl-ββ'-thio-di-propionate, di-myristyl-ββ'-thio-di-propionate, di-lauryl-ββ'-thio-di-propionate An antioxidant etc. are mentioned.

  As a specific example of the nucleating agent, a known nucleating agent can be used. For example, a known nucleating agent such as a sorbitol-based transparent nucleating agent, an amide-based nucleating agent, an organic phosphate-based transparent nucleating agent, an aromatic phosphate ester, or talc can be used.

Specific examples of the neutralizer include calcium fatty acid stearate, zinc stearate, magnesium stearate, aluminum stearate, lithium stearate and other metal fatty acid salts, hydrotalcite (trade name: Kyowa Chemical Industry Co., Ltd. (A magnesium aluminum composite hydroxide salt represented by (1)), Mizukarak (a lithium aluminum composite hydroxide salt represented by the following general formula (2)), and the like.
Mg _1-x Al _x (OH) ₂ (CO ₃ ) _{x / 2} · mH ₂ O (1)
[Wherein x is 0 <x ≦ 0.5, and m is a number of 3 or less. ]
[Al ₂ Li (OH) ₆ ] _n X · mH ₂ O (2)
[Wherein, X is an inorganic or organic anion, n is the valence of the anion (X), and m is 3 or less. ]

  Specific examples of the lubricant include known lubricants, and examples thereof include fatty acid amides such as oleic acid amide, stearic acid amide, erucic acid amide, and behenic acid amide, butyl stearate, and silicone oil.

  Examples of the ultraviolet absorber include 2-hydroxy-4-n-octoxybenzophenone, 2- (2′-hydroxy-3 ′, 5′-di-t-butylphenyl) -5-chlorobenzotriazole, 2- (2 And ultraviolet absorbers such as' -hydroxy-3'-t-butyl-5'-methylphenyl) -5-chlorobenzotriazole.

    Examples of the light stabilizer include n-hexadecyl-3,5-di-t-butyl-4-hydroxybenzoate, 2,4-di-t-butylphenyl-3 ′, 5′-di-t-butyl-4 ′. -Hydroxybenzoate, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, dimethyl-2- (4-hydroxy-2,2,6,6-tetramethyl-1-piperidyl) ethanol succinate Condensate, poly {[6-[(1,1,3,3-tetramethylbutyl) amino] -1,3,5-triazine-2,4-diyl] [(2,2,6,6-tetra Methyl-4-piperidyl) imino] hexamethylene [(2,2,6,6-tetramethyl-4-piperidyl) imino]}, N, N′-bis (3-aminopropyl) ethylenediamine-2,4-bis [N-butyl-N- 1,2,2,6,6-pentamethyl-4-piperidyl) amino] -6-chloro-1,3,5-triazine condensate, and the like of the light stabilizer.

  Further, an amine-based antioxidant represented by the following formula (3) or the following general formula (4), 5,7-di-t-butyl-3- (3,4-di-methyl-phenyl) -3H- Examples thereof include lactone antioxidants such as benzofuran-2-one and vitamin E antioxidants such as the following chemical formula (5).

［式中のＲ^１とＲ^２は、炭素数１４〜２２のアルキル基］

[Wherein R ¹ and R ² are alkyl groups having 14 to 22 carbon atoms]

  In addition, an antistatic agent, a dispersant such as a fatty acid metal salt, and the like can be blended within a range that does not impair the object of the present invention.

  In addition, the thermoplastic resin composition of the present invention is made of alumina, carbon black, calcium carbonate, silica, gypsum, talc as a filler in order to impart other characteristics or functions while maintaining the maximum characteristics of the composition. 1 to 30 parts by weight, preferably 1 to 10 parts by weight of various inorganic fillers such as mica, kaolin, clay, titanium oxide, and alumina can be optionally added.

[8] Method for Producing Thermoplastic Resin Composition The thermoplastic resin composition of the present invention comprises a propylene-ethylene block copolymer [I], a thermoplastic elastomer [II], and other additives used as necessary. Can be obtained by mixing in a Henschel mixer, a super mixer, a ribbon blender or the like and mixing (dry blending). Alternatively, after dry blending, it is obtained by further melt-kneading (melt blending) in a temperature range of about 180 to 280 ° C. with a normal single screw extruder, twin screw extruder, Banbury mixer, plastic bender, roll or the like. You can also. Furthermore, after adding necessary additives etc. with respect to each of propylene-ethylene block copolymer [I] and thermoplastic elastomer [II], and performing dry blend and melt blend separately, each polymer is added. It can also be obtained by dry blending.

[9] Molded Article The thermoplastic resin composition according to the present invention can be used for producing articles by any method such as extrusion, molding (for example, injection molding or blow molding), or thermoforming. Examples of articles include storage bottles, food storage containers, caps and lids, and various container seals.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited at all by these description.
In each example and comparative example, the physical properties used were measured by the following methods, and the following were used as propylene-ethylene block copolymers, thermoplastic elastomers, and other additives.

1. Measurement method (1) TREF
The TREF measurement method is as described above, and the apparatus and conditions are as follows.
[apparatus]
(TREF part)
TREF column: 4.3 mmφ × 150 mm stainless steel column Column packing material: 100 μm Surface inactive glass beads Heating method: Aluminum heat block Cooling method: Peltier element (Peltier element is cooled by water)
Temperature distribution: ± 0.5 ° C
Temperature controller: Chino digital program controller KP1000 (valve oven)
Heating method: Air bath oven Measurement temperature: 140 ° C
Temperature distribution: ± 1 ° C
Valve: 6-way valve 4-way valve

(Sample injection part)
Injection method: Loop injection method Injection volume: Loop size 0.1ml
Inlet heating method: Aluminum heat block measurement temperature: 140 ° C
(Detection unit)
Detector: Fixed wavelength infrared detector FOXBORO MIRAN 1A
Detection wavelength: 3.42 μm
High-temperature flow cell: Micro flow cell for LC-IR Optical path length: 1.5 mm Window shape: 2φ x 4 mm long circle Synthetic sapphire window measurement temperature: 140 ° C
(Pump part)
Liquid feed pump: SSC-3461 pump manufactured by Senshu Kagaku Co. [Measurement conditions]
Solvent: o-dichlorobenzene (containing 0.5 mg / mL BHT)
Sample concentration: 5 mg / mL
Sample injection volume: 0.1 mL
Solvent flow rate: 1 mL / min

(2) Solid viscoelasticity measurement A 10 mm × 18 mm × 2 mmt strip cut out from a molded sheet obtained by injection molding was used as a test piece. The apparatus used was ARES manufactured by Rheometric Scientific. The frequency is 1 Hz. The measurement temperature was raised stepwise from −60 ° C., and the measurement was performed until the sample melted and became impossible to measure. The strain was performed in the range of 0.1 to 0.5%.

(3) Calculation of each component amount It calculated by the method mentioned above using TREF.
(4) Calculation of ethylene content
The ethylene content in the random copolymer was measured by infrared spectroscopy using a characteristic absorber of 733 cm ⁻¹ with an ethylene / propylene random copolymer whose composition was verified by ¹³ C-NMR as a reference substance. The test piece used was a pellet made into a film having a thickness of about 500 microns by press molding.
(5) Peak of tan δ curve It was measured by intrinsic viscoelasticity measurement.

(6) MFR
Measurement was performed at a temperature of 230 ° C. and a load of 21.2 N in accordance with JIS K7210. However, the measurement temperature for the polyethylene polymer was 190 ° C.
(7) Melting peak temperature Using a Seiko Instruments RDC220U as a DSC tester, taking 5.0 mg of sample, holding at 200 ° C for 5 minutes, and then crystallizing to 40 ° C at a rate of temperature drop of 10 ° C / min. Further, the melting peak temperature when melted at a heating rate of 10 ° C./min was measured.

(8) Molecular weight distribution It measured by the above-mentioned method.
(9) Density The density was measured by a density gradient tube method in accordance with JIS K7112-1980 “Method for measuring density and specific gravity of plastic”.

(10) Flexural modulus Using a EC100 injection molding machine manufactured by Toshiba Machine, a test piece of 90 × 10 × 4 mm was produced at a molding temperature of 200 ° C. and a mold temperature of 30 ° C., and the test speed was in accordance with JIS K7203: 1982. The measurement was performed at 2 mm / min, a distance between fulcrums of 64 mm, and a test temperature of 23 ° C.
The flexural modulus is an index of flexibility. The smaller this value is, the more flexible the molded product is, and the better the sealing performance, opening performance, and the like.

(11) Duro Hardness Using a Toshiba Machine EC100 injection molding machine, a sheet-shaped test piece of 120 mm × 80 mm × 2 mmt was produced at a molding temperature of 200 ° C. and a mold temperature of 30 ° C., in accordance with JIS K7215-1996, at a test temperature of 23 Measured at ° C.
The durometer is an index of flexibility, and the smaller this value, the more flexible the molded product and the better the sealing performance, opening performance, and the like.

(12) Vicat softening temperature Using a Toshiba Machine EC100 injection molding machine, a sheet-shaped test piece of 120 mm × 80 mm × 2 mmt was produced at a molding temperature of 200 ° C. and a mold temperature of 30 ° C. Based on JIS K7206: 1991, the load was 500 g and the temperature increase rate was 120 ° C./h.
The Vicat softening temperature is an index of heat resistance. The higher this value is, the less the molded product is deformed even at high temperatures.

(13) HAZE
A sheet-shaped test piece of 100 mm × 100 mm × 1 mmt was produced at a molding temperature of 200 ° C. and a mold temperature of 30 ° C. with an IS100GN injection molding machine manufactured by Toshiba Machine, and measured according to JIS K7105: 1981.
The haze is an index of transparency. The smaller this value, the more transparent the molded product, and the better the appearance design and the visibility of the contents.

2. Materials used (1) Propylene-ethylene block copolymer (I)
By the following manufacture example 1, the propylene-ethylene block copolymer [I] used by this invention was obtained.

(Production Example 1: Production of propylene-ethylene block copolymer [I])
・ Manufacture of catalysts ・ ・ Chemical treatment of silicates:
To a 10-liter glass separable flask with a stirring blade, 3.75 liters of distilled water was added slowly followed by 2.5 kg of concentrated sulfuric acid (96%). At 50 ° C., 1 kg of montmorillonite (trade name manufactured by Mizusawa Chemical Co., Ltd., Benclay SL; average particle size = 50 μm) was further dispersed, heated to 90 ° C., and maintained at that temperature for 6.5 hours. After cooling to 50 ° C., the slurry was filtered under reduced pressure to recover the cake. 7 liters of distilled water was added to this cake to reslurry it, and then filtered. This washing operation was performed until the pH of the washing liquid (filtrate) exceeded 3.5. The collected cake was dried at 110 ° C. overnight under a nitrogen atmosphere. The weight after drying was 707 g. The chemically treated silicate was dried by a kiln dryer.

..Preparation of catalyst:
200 g of the dry silicate obtained above was introduced into a glass reactor with an internal volume of 3 liters, and 1160 ml of mixed heptane and 840 ml of a heptane solution of triethylaluminum (0.60 M) were added and stirred at room temperature. . After 1 hour, the mixture was washed with mixed heptane to prepare 2.0 l of silicate slurry. Next, 9.6 ml of a heptane solution of triisobutylaluminum (0.71 M / L) was added to the prepared silicate slurry and reacted at 25 ° C. for 1 hour. In parallel, [(r) -dichloro [1,1′-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4H-azurenyl}] zirconium] (the synthesis is described in JP-A-10-226712) This was carried out according to the method described in the Examples.) 33.1 ml of a heptane solution of triisobutylaluminum (0.71 M) was added to 2180 mg (3 mmol) and 870 ml of mixed heptane, and the mixture was allowed to react at room temperature for 1 hour. Added to the silicate slurry and stirred for 1 hour.

..Prepolymerization:
Subsequently, 2.1 liters of normal heptane was introduced into a stirring autoclave having an internal volume of 10 liters that had been sufficiently substituted with nitrogen, and maintained at 40 ° C. The previously prepared silicate / metallocene complex slurry was introduced therein. When the temperature was stabilized at 40 ° C., propylene was supplied at a rate of 100 g / hour to maintain the temperature. After 4 hours, the supply of propylene was stopped and maintained for another 2 hours. After completion of the prepolymerization, the remaining monomer was purged, stirring was stopped and the mixture was allowed to stand for about 10 minutes, and then about 3 liters of supernatant was decanted. Subsequently, 9.5 ml of a heptane solution of triisobutylaluminum (0.71 M / L) and 5.6 liters of mixed heptane were added, and the mixture was stirred at 40 ° C. for 30 minutes and allowed to stand for 10 minutes. Removed liters. This operation was further repeated 3 times.
When the component analysis of the final supernatant was performed, the concentration of the organoaluminum component was 1.23 mmol / L and the Zr concentration was 8.6 × 10 ⁻⁶ g / L, and the abundance in the supernatant with respect to the amount charged. Was 0.016%. Subsequently, 17.0 ml of a heptane solution of triisobutylaluminum (0.71 M / L) was added, followed by drying at 45 ° C. under reduced pressure. By this operation, a prepolymerized catalyst containing 2.1 g of polypropylene per 1 g of catalyst was obtained.

-Polymerization-1st polymerization process The polymerization apparatus of the flow sheet shown in FIG. 2 was used.
After introducing 35 kg of seed polymer in advance into a horizontal polymerization vessel 1 (L / D = 3.7, internal volume 100 L) having a stirring blade, nitrogen gas was circulated for 3 hours. Thereafter, the temperature was raised to 65 ° C. while introducing propylene, ethylene and hydrogen. The pressure of the reactor was set to 2.2 MPaG, and the conditions were adjusted so that ethylene / propylene (molar ratio) = 0.06 and hydrogen / propylene (molar ratio) = 0.0002 in the gas, and then the prepolymerized catalyst 0.9 g / hr (amount including the prepolymerized polymer) and triisobutylaluminum as an organoaluminum compound were fed so as to be constant at 15 mmol / hr. Propylene-ethylene random copolymer (A) was produced while maintaining the reaction temperature of 65 ° C., the reaction pressure of 2.2 MPaG, and the above conditions of ethylene / propylene and hydrogen / propylene.
The reaction heat was removed by the heat of vaporization of the raw material propylene supplied from the pipe 3. The unreacted gas discharged from the polymerization reactor was cooled and condensed outside the reactor system through the pipe 4 and refluxed to the polymerization reactor 1. The propylene-ethylene random copolymer (A) obtained by the main polymerization is intermittently withdrawn from the polymerization vessel 1 through the pipe 5 so that the retained level of the polymer is 65% by volume of the reaction volume. The polymerization vessel 10 was supplied. At this time, the production amount of the propylene-ethylene random copolymer (A) was 7 kg / hr. A part of the propylene-ethylene random copolymer (A) was extracted from the pipe 5 and used as a sample for analysis.

.. Second polymerization step The propylene-ethylene random copolymer (A) from the first polymerization step is intermittently supplied to a horizontal polymerization vessel 10 (L / D = 3.7, internal volume 100 L) having a stirring blade. Copolymerization of propylene and ethylene was performed. The reaction conditions are stirring speed 18 rpm, reaction temperature 70 ° C., reaction pressure 2.1 MPaG, gas ethylene / propylene (molar ratio) = 0.43, hydrogen / [propylene + ethylene] (molar ratio) = 0.0003. It adjusted so that it might become. Oxygen gas was supplied from the piping 7 as a polymerization activity inhibitor for adjusting the polymerization amount of the propylene-ethylene random copolymer (B).
The reaction heat was removed by the heat of vaporization of the raw material propylene supplied from the pipe 6. The unreacted gas discharged from the polymerization vessel was cooled and condensed outside the reactor system through the pipe 8 and refluxed to the polymerization vessel 10. The propylene-ethylene block copolymer (I) produced in the second doubling step was intermittently withdrawn from the polymerizer 10 through the pipe 9 so that the retained level of the polymer was 50% by volume of the reaction volume.

-Analysis result of propylene-ethylene block copolymer (I) MFR of the propylene-ethylene block copolymer (I) obtained above is 6 g / 10 min, Tm is 130 ° C, and the content of component (A) is 56 wt%, component (B) content is 44 wt%, component (A) MFR is 6 g / 10 min, ethylene content is 2.2 wt%, ethylene content in component (B) is 11 wt% there were.
Table 3 summarizes the production conditions and the analysis results of the propylene-ethylene block copolymer (I).

(2) Thermoplastic elastomer incompatible with propylene-ethylene block copolymer [I] The following thermoplastic elastomer was used as a thermoplastic elastomer incompatible with propylene-ethylene block copolymer [I]: ethylene Elastomer made by Nippon Polyethylene Co., Ltd., trade name “Kernel KS571”
Metallocene-catalyzed ethylene-hexene copolymer MFR 12 g / 10 min, density 0.907 g / cm ³
・ Ethylene-based elastomer, manufactured by Nippon Polyethylene, trade name “Kernel KS560T”
Metallocene-catalyzed ethylene-hexene copolymer MFR 16.5 g / 10 min, density 0.898 g / cm ³

(3) Other additives (antioxidant A)
・ Hindered phenolic antioxidants:
Product name “Irganox 1010” (IR1010), manufactured by Ciba
Tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxylphenyl) propionate] methane (antioxidant B)
・ Phosphorus antioxidants:
Product name “Irgaphos 168” (IF168), manufactured by Ciba
Tris (2,4-di-tert-butylphenol) phosphite

(Examples 1-5, Comparative Examples 1-2)
Propylene-ethylene copolymer, thermoplastic elastomer, and antioxidant were prepared in the blending ratios (parts by weight) shown in Table 4, dry blended with a super mixer, and then melted using a 35 mm diameter twin screw extruder. Kneaded. Extruded pellets from the die at a die outlet temperature of 200 ° C. The obtained pellets were injection molded by an injection molding machine at a resin temperature of 200 ° C., an injection pressure of 600 kg / cm ^2, and a mold temperature of 20 ° C. to prepare test pieces.
The physical properties were measured using the obtained test pieces. The results are shown in Table 4.

As is apparent from the above table, in Examples 1 to 5, high transparency is obtained while maintaining flexibility and heat resistance by using an appropriate amount of the specific thermoplastic elastomer [II].
On the other hand, since the thermoplastic elastomer [II] is not included in Comparative Example 1, the transparency is deteriorated. In Comparative Example 2, since the ratio of the thermoplastic elastomer [II] is large, it has flexibility but is inferior in heat resistance, and transparency is not sufficiently obtained.

  The thermoplastic resin composition of the present invention is a composition having high flexibility, heat resistance, and high transparency, and a molded product obtained by molding the composition is a storage bottle, a food storage container, It is extremely suitable for the use of caps and lids, and various container seals.

Claims (6)

90 to 99.5 parts by weight of a propylene-ethylene block copolymer [I] satisfying the following (i) to (v), and a thermoplastic elastomer [II] incompatible with the propylene-ethylene block copolymer [I] ] 0.5 to 10 parts by weight (however, the total of both is 100 parts by weight).
(I) Using a metallocene-based catalyst, 30 to 95 wt% of propylene-ethylene random copolymer component (A) having propylene homopolymer or ethylene content of 7 wt% or less in the first step, and from component (A) in the second step A propylene-ethylene block copolymer obtained by sequential polymerization of 70 to 5 wt% of the propylene-ethylene random copolymer component (B) containing 3 to 20 wt% of ethylene (ii) Melt flow The rate (MFR: 230 ° C., 2.16 kg) is in the range of 0.5 to 100 g / 10 min. (Iii) The melting peak temperature (Tm) measured by the DSC method is in the range of 110 to 150 ° C. (Iv) The molecular weight distribution (Mw / Mn) measured by the GPC method is in the range of 1.5 to 4 (v) obtained by solid viscoelasticity measurement. Temperature - In the loss tangent (tan [delta) curve, the tan [delta curve has a single peak at 0 ℃ below   The thermoplastic resin composition according to claim 1, wherein the amount of the thermoplastic elastomer [II] is 1 to 5 parts by weight.   The thermoplastic resin composition according to claim 1 or 2, wherein the thermoplastic elastomer [II] is a thermoplastic elastomer composed of ethylene and an α-olefin having 3 to 10 carbon atoms.   The thermoplastic resin composition according to claim 1 or 2, wherein the thermoplastic elastomer [II] is a thermoplastic elastomer composed of ethylene and an α-olefin having 3 to 10 carbon atoms.   The molded article formed by shape | molding the thermoplastic resin composition of any one of Claims 1-4.   The molded article according to claim 5, wherein the molded article is a food storage container.

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