JPH0655548A - Cleaning agent for molding machine - Google Patents

Abstract

PURPOSE:To reduce amt. of a transitional product after switching of a molding material by using a block copolymer contg. each specified amt. of polybutene component, polypropylene component and propylene-ethylene random copolymer component and with a specified melt index as a cleaning agent for a molding machine. CONSTITUTION:A block copolymer used contains 0.01-5wt.% polybutene component, 1-70wt.% polypropylene component and 25-98.99wt.% propylene-ethylene random copolymer component. In addition, 15-80 mole % monomer unit based on ethylene and 85-20 mole % monomer unit based on propylene are incorporated in the random copolymer component. This block copolymer is obtd. as a high mol. wt. powder with excellent fluidity by polymerization. This is used by reducing it with an org. peroxide to adjust MI to 0.01-6g/min. In addition, when an org. foaming agent is used in parallel, a better cleaning effect for a screw and a cylinder of a molding machine is obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding machine cleaning agent used for cleaning screws and cylinders of injection molding machines, extrusion molding machines, blow molding machines and the like used for molding various thermoplastic resins.

[0002]

2. Description of the Related Art There are many types of thermoplastic resins, and many grades with different types and amounts of additives. In the molding process of these thermoplastic resins, a method of continuously molding using the same molding machine is usually adopted, especially when different grades of the same resin are used. However, when continuously molding these different grades of molding material, a large amount of a transient product in which the molding material that is molded before and the molding material that is molded later are mixed for a while after the switching is generated. was there.

In order to reduce the amount of transient products mentioned above, polyolefins are passed through a molding machine to clean the screws and cylinders of the molding machine after the previous molding material has been molded. There is. By this operation, the amount of transient products after switching the molding material can be reduced to some extent.

[0004]

However, even with this method, the amount of transient products after the change of the molding material cannot be sufficiently reduced. Therefore, it is an object of the present invention to reduce the amount of transient products after switching of molding material when molding different grades of molding material in succession.

[0005]

DISCLOSURE OF THE INVENTION The inventors of the present invention have conducted extensive research on cleaning agents for screws and cylinders of molding machines, and as a result, a block copolymer having a specific composition and MI achieves the above object. It was found that they could be the following, and the present invention was completed.

That is, the present invention is a block copolymer containing a polybutene component, a polypropylene component, and a propylene-ethylene random copolymer component, wherein the polybutene component is 0.01 to 5% by weight and the polypropylene component is 1 to 5.
70% by weight, the propylene-ethylene random copolymer component is 25 to 98.99% by weight, and the propylene-ethylene random copolymer component is 15 to 80 mol% of ethylene-based monomer units and propylene-based. Contains 85 to 20 mol% of a monomer unit and has MI of 0.01 to 6 g / 1
It is a molding machine cleaner composed of a block copolymer of 0 minutes.

In the present invention, the block copolymer comprises a polybutene component, a polypropylene component and a propylene-ethylene copolymer component. When the polybutene component is replaced with another component, for example, the polyethylene component, the solidification property of the polymer particles obtained by the polymerization and the poor fluidity at high temperature,
Manufacturing becomes difficult.

In the block copolymer used in the present invention, the polybutene component, the polypropylene component and the propylene-ethylene random copolymer component each have a component ratio of 0.01 to 5% by weight of the polybutene component and 1 to 70 of the polypropylene component. %, And the propylene-ethylene random copolymer component is 25 to 98.99% by weight.

In the present invention, the polybutene component is essential for improving the particle properties of the copolymer particles. In particular,
When the content of polypropylene component is low, for example, 30
When it is at most 10% by weight, the resulting copolymer particles tend to stick, but even in such a case, the presence of the polybutene component makes it possible to obtain copolymer particles having good fluidity. When the polybutene component is less than 0.01% by weight,
When the copolymer particles obtained by the polymerization are deposited and left to stand, they are solidified by the load, and further 50 to 50
When the temperature is 70 ° C, the fluidity is remarkably inferior, which is not preferable. On the other hand, when the polybutene component exceeds 5% by weight, the fluidity of the block copolymer is rather lowered, which is not preferable. The proportion of the polybutene component is preferably in the range of 0.04 to 3% by weight in consideration of the better fluidity of the block copolymer particles.

If the polypropylene component is less than 1% by weight or exceeds 70% by weight, the cleaning effect of the molding machine is not sufficient. Considering the cleaning effect, the polypropylene component is preferably in the range of 3 to 60% by weight.

Further, the ethylene-propylene random copolymer component is 25 to 98.99% by weight. When the content of the above components is less than 25% by weight, or when it exceeds 98.9% by weight, the cleaning effect of the molding machine becomes poor, which is not preferable. Considering the cleaning effect, the ethylene-propylene random copolymer component is preferably in the range of 40 to 97% by weight.

The block copolymer used in the present invention includes:
Any one or more of polybutene component, polypropylene component, propylene-ethylene random copolymer component,
Other α-olefins may be copolymerized and contained in a small amount, for example, 5 mol% or less, as long as the physical properties of the block copolymer are not impaired.

The block copolymer used in the present invention is a so-called block copolymer molecular chain in which at least two kinds of polybutene component, polypropylene component and propylene-ethylene random copolymer component are arranged in one molecular chain. It is considered that the polybutene component, the polypropylene component, and the propylene-ethylene random copolymer component are mixed with the molecular chains of the individual so finely that they cannot be achieved by mechanical mixing.

The polybutene component in the block copolymer used in the present invention is used to prevent the particles of the block copolymer from solidifying,
In order to improve the fluidity at high temperature, the isotacticity is preferably 0.90 or more. Poly 1-
The isotacticity of butene was measured by ¹³ C-NMR, and the polymer journal (Polymer) was used.
J.) Volume 16 (1984) pp. 716-726.

The content ratio of each of the ethylene-based monomer unit and the propylene-based monomer unit in the propylene-ethylene random copolymer component is
The monomer unit based on ethylene is 15 to 80 mol%, preferably 15 to 60 mol%, more preferably 20 to 50 mol%. 85 to 20 monomer units based on propylene
It is mol%, preferably 85 to 40 mol%, more preferably 80 to 50 mol%. When the content ratio of ethylene-based monomer units is less than 15 mol% and the content ratio of propylene-based monomer units exceeds 85 mol%, and when the content ratio of ethylene-based monomer units is 80 mol%. %, And the content ratio of the propylene-based monomer unit is less than 20 mol%, the cleaning effect of the molding machine decreases, which is not preferable.

The block copolymer used in the present invention is obtained as a powder having excellent fluidity by polymerization. This is surprising considering that a conventional propylene-ethylene random copolymer having an ethylene content similar to that of the block copolymer used in the present invention is obtained in a lump form due to sticking of particles to each other.

The average particle size of the block copolymer used in the present invention is not particularly limited, but is usually 100 to 1000 μm.
m, particularly preferably in the range of 100 to 800 μm.
The particle size distribution is not particularly limited, but is usually relatively narrow, and specifically, the proportion of powdery particles having a particle size of 100 μm or less is 1% by weight or less, and the particle size is 1000 μm or more, preferably the particle size is 100 μm or more. It is preferable that the ratio of the powdery material having a size of 800 μm or more is 1% by weight or less.

The block copolymer used in the present invention is obtained in a high molecular weight by polymerization, and is degraded by an organic peroxide described later to adjust MI to 0.01 to 6 g / min. When the MI is out of the above range, the effect as a cleaning agent for a molding machine is poor, which is not preferable.

The block copolymer used in the present invention may be obtained by any method. The method that is particularly preferably adopted is as follows.

That is, the following components A and B, or C and / or D A. Titanium compound B. Organoaluminum compound C.I. Electron donor D. In the presence of an iodine compound represented by the general formula (i) RI (i) (wherein R is an iodine atom or an alkyl group having 1 to 7 carbon atoms or a phenyl group), 0.1 to 0.1% of propylene is added. 500g polymer / g
-Preliminary polymerization is carried out to obtain a Ti compound in the range to obtain a catalyst-containing prepolymer, and then 1-butene and propylene are polymerized in the presence of the catalyst-containing prepolymer to obtain a mixture of propylene and ethylene. A method in which random copolymerization of the mixture is sequentially performed to obtain a high-molecular weight powdery substance and then degradation with an organic peroxide is performed to adjust MI to 0.01 to 6 g / min is preferable.

As the titanium compound [A] used in the prepolymerization in the above method for producing a block copolymer, a titanium compound known to be used for olefin polymerization can be employed without any limitation. As a method for producing this catalyst, a known method is adopted without any limitation. For example, JP-A-56-155206, 56-136806, 57-34103, 58-8706, 58-830.
06, 58-138708, 58-183709, 59-206408, 59-21
9311, 60-81208, 60-81209, 60-186508, 60-19
2708, 61-211309, 61-271304, 62-15209, 62-1
1706, 62-72702, 62-104810, etc. are adopted. Specifically, for example, a method of co-milling titanium tetrachloride with a magnesium compound such as magnesium chloride, a method of co-milling titanium halide with a magnesium compound in the presence of an electron donor such as alcohol, ether, ester ketone or aldehyde. The method of pulverization or the method of bringing a titanium halide, a magnesium compound and an electron donor into contact with each other in a solvent can be mentioned.

As the titanium compound, in addition to the above-mentioned supported catalyst, known α, β, γ or δ-titanium trichloride is also preferably used. The method for preparing these titanium compounds is, for example, JP-A-47-34478, 50-126590, 50-11439.
4, same 50-93888, same 50-123091, same 50-74594, same 50-10419
1, 50-98489, 51-136625, 52-30888, 52-35283
Etc. are adopted.

Next, as the organoaluminum compound [B], a compound known to be used for the polymerization of olefins can be adopted without any limitation. For example, trimethyl aluminum, triethyl aluminum, tri-n propyl aluminum, tri-n butyl aluminum, tri-i butyl aluminum, tri-n hexyl aluminum, tri-
Trialkylaluminums such as n-octylaluminum and tri-ndecylaluminum; Diethylaluminum monohalides such as diethylaluminum monochloride and diethylaluminium bromide; Alkylaluminum halides such as methylaluminum sesquichloride, ethylaluminum sesquichloride and ethylaluminum dichloride And the like. Other alkoxy aluminums such as monoethoxydiethylaluminum and diethoxymonoethylaluminum can be used.

Further, as the electron donor [C], compounds known to be used for improving the stereoregularity of olefins are adopted without any limitation. For example, alcohols such as methanol, ethanol, propanol, butanol, pentanol, hexanol, octanol, isopropyl alcohol, isoamyl alcohol; phenols such as phenol, cresol, cumylphenol, xylenol, naphthol; acetone, methyl ethyl ketone, acetophenone, benzophenone Ketones such as;
Aldehydes such as acetaldehyde, propionaldehyde, benzaldehyde; methyl formate, methyl acetate,
Ethyl acetate, vinyl acetate, methyl propionate, ethyl propionate, methyl butyrate, ethyl butyrate, ethyl valerate, ethyl stearate, ethyl acrylate, methyl methacrylate, ethyl benzoate, methyl toluate, methyl anisate, phthalic acid Organic acid esters such as ethyl, methyl carbonate and butyrolactone; silicic acid esters such as ethyl silicate and phenyltriethoxysilane; ethers such as methyl ether, ethyl ether, isopropyl ether, isoamyl ether, tetrahydrofuran, anisole and diethylene glycol dimethyl ether Oxygen-containing electron donors such as amides such as acetic acid amide, benzoic acid amide, maleic acid amide; amines such as methylamine, ethylamine, piperidine, pyridine and aniline; aceto Tolyl, nitriles such as benzonitrile; nitrogen-containing electron donors such as isocyanate: sulfur-containing electron donor: and the like and phosphorus-containing electron donors may be mentioned.

In the present invention, when an iodine compound [D] represented by the general formula (i) is used in addition to the above titanium compound [A], organoaluminum compound [B] and electron donor [C], This is often preferable because the amount of the low molecular weight polymer having a molecular weight of 10,000 or less is remarkably reduced and the block copolymer can be provided with high fluidity.

Specific examples of the iodine compounds that can be preferably used in the present invention are as follows. For example, iodine, methyl iodide, ethyl iodide, propyl iodide, butyl iodide, iodobenzene, p-iodinated toluene and the like.
Methyl iodide and ethyl iodide are particularly preferable.

The amounts of the above-mentioned components [A] and [B], and optionally [C] and / or [D], used differ depending on the type of catalyst and the prepolymerization conditions. The optimum usage amount may be determined in advance according to each of these conditions. An example of the range generally used preferably is as follows.

That is, the use ratio of the organoaluminum compound [B] is 0.1 to 100, preferably 0.1 to 20 in terms of Al / Ti (molar ratio) with respect to the titanium compound [A]. The ratio of the electron donor [C] used according to the above is 0.01 to 100, preferably 0.01 to 10, in terms of [C] / Ti (molar ratio) with respect to the titanium compound [A].
The respective ranges are preferable. Further, the use ratio of the iodine compound [D] used as necessary is 0.1 to 100 in terms of I / Ti (molar ratio) with respect to the titanium compound [A],
The range of 0.5 to 50 is preferable.

The prepolymerization in the present invention is an important factor in controlling the particle properties of the resulting block copolymer. The polymer obtained by the prepolymerization in which propylene is polymerized in the presence of the catalyst component is generally 0.1 to 500 g / g · Ti compound, preferably 1 to 100 g / g · Ti compound, although it varies depending on the prepolymerization conditions. It is enough to choose from the range. Further, propylene used in the prepolymerization is suitable in terms of controlling the particle properties of the block copolymer obtained by using a monomer of propylene alone, but within a range that does not adversely affect the physical properties of the block copolymer, for example, It is acceptable to mix up to 5 mol% of other α-olefins such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methylpentene-1 and the like. It is also possible to coexist with hydrogen at each prepolymerization stage.

It is preferable to apply slurry polymerization as the prepolymerization, and a saturated aliphatic hydrocarbon or aromatic hydrocarbon such as hexane, heptane, cyclohexane, benzene and toluene is used alone or a mixed solvent thereof as a solvent. Can be used. The prepolymerization temperature is −
20-100 degreeC, especially the temperature of 0-60 degreeC are preferable. The pre-polymerization time may be appropriately determined depending on the pre-polymerization temperature and the polymerization amount in the pre-polymerization, and the pressure in the pre-polymerization is not limited, but in the case of slurry polymerization, it is generally from atmospheric pressure to 5 kg / cm. It is about ² G. The prepolymerization may be carried out batchwise, semi-batchly or continuously.

After the completion of the prepolymerization, it can be directly used for the polymerization of 1-butene described later. After washing with the above solvent, it can be subjected to polymerization of 1-butene.

After the preliminary polymerization, main polymerization is carried out. In the main polymerization, 1-butene is first polymerized in the presence of the catalyst-containing prepolymer obtained in the prepolymerization, then propylene is polymerized, and then propylene-ethylene random copolymerization is carried out.

The catalyst used in the main polymerization of the present invention may be the same catalyst components as those used in the prepolymerization and combinations thereof, or may be chemically modified in the main polymerization step before use. The catalyst components used in the prepolymerization may be used as they are, but generally, it is preferable to newly add and control the components other than the titanium compound during the main polymerization.

As the organoaluminum compound used in the main polymerization, those used in the above-mentioned prepolymerization can be used. The amount of the organic aluminum compound used is 1 to 10 in terms of Al / Ti (molar ratio) with respect to the titanium atom in the catalyst-containing prepolymer.
00, preferably 2 to 500.

Further, as the electron donor optionally used, the above-mentioned compounds can be adopted without any limitation. The amount of the electron donor used in the main polymerization is 0.001 to [C] / Ti (molar ratio) with respect to the Ti atom in the catalyst-containing prepolymer.
It is 1000, preferably 0.1 to 500. Furthermore, the iodine compound used if necessary is I / Ti (molar ratio) of 0.1 with respect to the titanium atom in the catalyst-containing prepolymer.
1 to 100, preferably 0.5 to 50.

In the main polymerization in the present invention, first, 1-butene is the above-mentioned catalyst-containing prepolymer, an organoaluminum compound,
If necessary, it is carried out in the presence of a catalyst component of an electron donor and / or an iodine compound. The polymerization of 1-butene may be carried out by gas phase polymerization, but in general, solution polymerization in the above solvent or slurry polymerization in a 1-butene medium may be carried out. The polymerization temperature is preferably -20 to 100 ° C, particularly preferably 0 to 60 ° C. The polymerization time may be appropriately determined depending on the temperature and the amount of polymerization, but generally it may be selected from the range of 15 minutes to 3 hours. The polymerization pressure is not particularly limited, and in the case of solution polymerization, it is generally atmospheric pressure to 5 Kg / cm ² G
It is a degree.

Other conditions for the polymerization of 1-butene may be appropriately selected and carried out as long as the effects of the present invention are achieved. Generally, the resulting block copolymer has a high molecular weight and a molecular weight of 10,000 or less. It is preferable to select each condition so that the amount of the polymer is 1.0% by weight or less. Furthermore, each condition can be selected so that the tacticity is 0.90 or more in mm (triad). It is sufficient to select the polymerization amount of 1-butene to be 0.1 to 500 g / g · Ti compound, preferably 1 to 200 g / g · Ti compound. The polymerization conditions are preferably determined in advance so that the polybutene component in the resulting block copolymer is in the range of 0.01 to 5% by weight.

The block copolymer obtained in the present invention becomes particles having excellent anti-caking properties and fluidity at 50 to 70 ° C. Therefore, it is most preferable that the 1-butene is a homopolymer. . However, α-olefins other than 1-butene, such as ethylene, propylene, 3-methylbutene, and 4-methyl-, as long as the properties are not adversely affected.
It is permissible to copolymerize 1-pentene, 1-hexene and the like in a mixed state. The permissible amount varies depending on various polymerization conditions, but in general, other α-olefin is 5 mol%
It is preferable to select the following mixing ratio. In addition, the polymerization of the 1-butene can be carried out in the presence of hydrogen as a molecular weight modifier, if necessary.

After the above-mentioned 1-butene polymerization, propylene polymerization is carried out. Polymerization of propylene may be carried out by feeding in a mixture of propylene and up to 5 mol% of an acceptable α-olefin. Polymerization of propylene can be carried out in the same manner as the above-mentioned polymerization of 1-butene. As an example of the propylene polymerization conditions, the polymerization temperature is preferably as low as possible in order to increase the bulk specific gravity of the block copolymer, and for example, 80 ° C. or lower, and more preferably 20 to 70 ° C. Is preferred. If necessary, hydrogen may be allowed to coexist as a molecular weight modifier. Further, the polymerization may be any method such as slurry polymerization using propylene itself as a solvent, gas phase polymerization, solution polymerization, or the like. Considering the simplicity of the process, the reaction rate, and the particle properties of the block copolymer produced, slurry polymerization using propylene itself as a solvent is the most preferred embodiment. The polymerization system may be a batch system, a semi-batch system, or a continuous system, and the polymerization may be carried out in two or more stages under different conditions.

Next, propylene-ethylene random copolymerization is carried out. In the propylene-ethylene random copolymerization, propylene-based monomer units are 20 to 85 mol%, preferably 40 to 85 mol% and ethylene-based monomer units are 15 to 80 mol%, preferably 15 to 60 mol%.
Propylene and ethylene may be mixed and used so as to be in the range of mol%. Therefore, it is preferable to select the mixing ratio of propylene and ethylene such that the ethylene concentration in the gas state is 7 to 50 mol%, preferably 10 to 40 mol%. As the other conditions, the same conditions as the above-mentioned polymerization of propylene can be adopted.

The above-mentioned main polymerization may be carried out by appropriately selecting the conditions so long as the target product is obtained in the form of powder, but generally, the high molecular weight, for example, the weight average molecular weight is at least 6.
0,000 or more, usually 800,000 or more, preferably 1 million or more,
More preferably 1.3 to 7 million, most preferably 15
In the elution curve measured by gel permeation chromatography (hereinafter abbreviated as "GPC"), the proportion of components having a molecular weight of 10,000 or less is usually 1.0% by weight or less, preferably 0. It is preferable to select each condition so as to be 6% by weight or less.

After completion of the main polymerization, the particulate polymer can be obtained by evaporating the monomers from the polymerization system.

A known method can be used for the degradation of the block copolymer obtained above with an organic peroxide. As the organic peroxide, known compounds can be used without any limitation. Typical examples include, for example, ketone peroxides such as methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, cyclohexanone peroxide; isobutyryl peroxide. , Diacyl peroxides such as lauroyl peroxide and benzoyl peroxide; hydroperoxides such as diisopropylbenzene hydroperoxide; dicumyl peroxide, 2,5-dimethyl-2,5-di-
(T-Butylperoxy) hexane, 1,3-bis-
(T-butylperoxy-isopropyl) -benzene,
Di-t-butyl peroxide, 2,5-dimethyl-
2,5-di- (t-butylperoxy) -hexane-3
Peroxyketals such as 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane and 2,2-di- (t-butylperoxy) -butane; t- Examples thereof include alkyl peresters such as butyl peroxy-pivalate and t-butyl peroxy benzoate; percarbonates such as t-butyl peroxy isopropyl carbonate.

The compounding amount of the above-mentioned organic peroxide may be selected so that the MI is 0.01 to 6 g / 10 minutes. Generally, it is 0.0 per 100 parts by weight of the block copolymer.
It is preferably in the range of 01 to 5 parts by weight, more preferably 0.002 to 3 parts by weight.

Further, when melting with the above-mentioned organic peroxide, a compound having two or more radically polymerizable groups in one molecule (hereinafter, also referred to as a cross-linking agent) can be present. As the cross-linking agent, known compounds can be adopted without any limitation. Specifically, divinyl compounds such as divinylbenzene; diallyl phthalate,
Diallyl compounds such as diallyl terephthalate, diallyl isophthalate, diallyl tartrate, diallyl epoxysuccinate, diallyl malate and diallyl carbonate; P
Oxime compounds such as quinonedioxime, P, P-dibenzoylquinonedioxime; maleimide compounds such as phenylmaleimide; cyanuric acid or isocyanuric acid di- or triallyl such as triallyl cyanurate, triallyl isocyanurate Ester; Acrylic acid and methacrylic acid ester compounds such as ethylene glycol methacrylate, diethylene glycol dimethacrylate and pentaerythritol triacrylate; Liquid 1,2-polybutadiene and other oligomers having a double bond in the main chain or side chain; Syndiotactic- Examples thereof include polymers having a double bond in the main chain or side chain such as 1,2-polybutadiene.

The amount of the above-mentioned crosslinking agent to be compounded is not particularly limited, but is generally in the range of 0.01 to 20 parts by weight, and further 0.02 to 10 parts by weight with respect to 100 parts by weight of the block copolymer. It is preferable.

The above-mentioned block copolymer, organic peroxide and, if necessary, a cross-linking agent are kneaded at a temperature not lower than the melting point of the block copolymer and the decomposition temperature of the organic peroxide. It is carried out using a known kneading device. For example, screw extruder, Banbury mixer,
A method of kneading using a mixing roll or the like at 160 to 330 ° C, preferably 170 to 300 ° C can be adopted. Further, the melt-kneading can be performed in a stream of an inert gas such as nitrogen gas. It should be noted that prior to melt-kneading, it is also possible to carry out preliminary mixing using a known mixing device such as a tumbler or a Henschel mixer.

In the present invention, it is preferable to use an organic foaming agent in combination with the above block copolymer in order to obtain a better cleaning effect. As the organic foaming agent, a known foaming agent having a decomposition temperature not lower than the melting temperature of the block copolymer can be used without particular limitation. Specific examples of the organic foaming agent that can be used in the present invention include azo compounds such as azodicarbonamide and barium azodicarboxylate: nitro compounds such as N, N'-dinitropentamethylenetetramine: sulfonyl compounds such as P-toluenesulfonyl semicarbazide. A hydrazide compound can be mentioned.

The organic foaming agent may be previously kneaded at a temperature lower than the decomposition temperature of the block copolymer and the organic foaming agent, and when the block copolymer is used as a molding machine cleaner. Alternatively, they may be mixed with the block copolymer before being introduced into the molding machine to be washed.

The block copolymer obtained in the present invention can be appropriately blended with other resins, known additives such as antioxidants, light stabilizers, antistatic agents and the like.

[0051]

The block copolymer used in the present invention has the effect of cleaning the screw and cylinder of a molding machine. For this reason, when the same molding machine is used to continuously mold molding materials having different pigments and other additives, the cleaning agent of the present invention is put into the molding machine before molding the next molding material. By passing it, the former molding material can be easily discharged from the molding machine, and the latter molding material can be easily switched. Therefore, it is possible to suppress the amount of transient products generated due to switching between the former molding material and the latter molding material.

[0052]

EXAMPLES The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited to these examples.

The measuring method used in the following examples will be described.

1) The weight average molecular weight and the ratio of the molecular weight of 10,000 or less were measured by the GPC (gel permeation chromatography) method. Waters GPC-15
O-dichlorobenzene as a solvent at 0C, 135 ° C
I went there. The column used was TSK gel manufactured by Tosoh Corporation.
GMH6-HT, gel size 10-15μ. The calibration curve has a weight average molecular weight of 950, 290 as a standard sample.
It was prepared using 0, 10,000, 50,000, 49.8 million, 2.7 million and 6.75 million polystyrene.

2) Method for measuring respective ratios of ethylene-based monomer units and propylene-based monomer units in propylene-ethylene random copolymer component and method for measuring polybutene component ratio ¹³ C-NMR spectrum chart Was calculated using.
That is, the respective proportions of the ethylene-based monomer unit and the propylene-based monomer unit in the propylene-ethylene random copolymer component are determined by first determining the polymer (P
Polymer, Vol. 29 (1988), page 1848, to determine the assignment of peaks, and then by Macromolecules, Vol. 10, (1977), page 773. The respective proportions of ethylene-based monomer units and propylene-based monomer units were calculated.

Then, the weight and ratio of the polybutene component were calculated from the integrated intensity ratio of the peak derived from methyl carbon in the monomer unit and the peak derived from methyl carbon in the polybutene component based on propylene.

3) Measurement of isotacticity of poly 1-butene Measurement by ¹³ C-NMR, Polymer Journal (Polymer J.) Vol. 16 (1984) 71
Based on pages 6-726.

4) Particle size distribution Opening 75, 125, 250, 355, 500, 71
A 0,1180 μm sieve was charged with about 5 g of the polymer particles, and the mixture was classified on a sieve shaker for 10 minutes.

5) Falling seconds at 70 ° C. An outlet having a diameter of 10 mm is provided at the center of the bottom and a height of 175 m.
m, the inner diameter of the upper cylinder is 68 mm, and the height of the cylinder is 60
Put 100 ml of polymer particles preliminarily kept at 70 ° C into a metal funnel having a shape of mm, discharge the polymer particles while applying a vibration of 2 mm width in the lateral direction, and measure the time required for discharging the whole amount. did.

6) Evaluation of caking property After the completion of the polymerization, about 100 g of polymer particles separated into monomers
Was placed in a 500 cc beaker having a diameter of 8 cm and a height of 15 cm and allowed to stand at room temperature for 1 week, and then the state was observed. The criteria for evaluation were the following 5 ranks.

A: Almost no change from that before standing and no solidification. B: The bottom is in a solidified state, but it is unraveled when an impact is applied C: The whole is solidified, but the whole is untied when an impact is applied D: The whole is solidified and a shock is applied Even when the whole is not loosened E: It is in a state where it is significantly solidified and does not move in a lump 7) It was measured according to MI JIS K7210.

Production Example 1 (Preliminary Polymerization) A glass autoclave reactor having an internal volume of 1 liter equipped with a stirrer was sufficiently replaced with nitrogen gas, and then 400 ml of heptane was charged. Set the reactor temperature to 2
Keeping at 0 ° C., diethylene glycol dimethyl ether 0.18 mmol, ethyl iodide 22.7 mmol, diethyl aluminum chloride 18.5 mmol, and titanium trichloride (“TOS-1” manufactured by Marubeni Solvay Chemical Co., Ltd.).
7 "), 22.7 mmol was added, and then propylene was continuously introduced into the reactor for 30 minutes such that the amount of propylene was 3 g per 1 g of titanium trichloride. The temperature during this period was kept at 20 ° C. After stopping the supply of propylene, the inside of the reactor was sufficiently replaced with nitrogen gas, and the obtained titanium-containing polypropylene was washed with purified heptane four times. As a result of the analysis, 2.9 g of propylene was polymerized per 1 g of titanium trichloride.

(Main Polymerization) Step 1: Polymerization of 1-Butene A stainless steel autoclave reactor having an internal volume of 1 liter equipped with a stirrer was sufficiently replaced with nitrogen gas, and then 400 ml of heptane was charged. Keeping the temperature inside the reactor at 20 ° C, diethyl aluminum chloride 18.15mmo
1, diethylene glycol dimethyl ether 0.18m
mol, ethyl iodide 22.7 mmol, 22.7 mmol of titanium-containing polypropylene obtained by prepolymerization as titanium trichloride, and then 1-butene was continuously added for 2 hours so that 1 g of titanium trichloride was 15 g. It was introduced into the reactor. The temperature during this period was kept at 20 ° C.
After the supply of 1-butene was stopped, the inside of the reactor was replaced with nitrogen gas to obtain a titanium-containing poly-1-butene polymer. As a result of the analysis, 14 g of 1-butene was polymerized per 1 g of titanium trichloride.

Step 2: Polymerization of Propylene and Copolymerization of Propylene Ethylene 1 liter of liquid propylene and 0.70 mmol of diethylaluminum chloride were added to a 2 liter autoclave subjected to N ₂ substitution, and the internal temperature of the autoclave was adjusted to 70 ° C. The temperature was raised. 0.087 mmol of titanium-containing poly-1-butene polymer was added as titanium trichloride, and propylene was polymerized at 70 ° C. for 60 minutes. During this time, hydrogen was not used. Then, the internal temperature of the autoclave is rapidly increased to 55
At the same time as the temperature was lowered to ° C, a mixed solution of 0.50 mmol of ethylaluminum sesquiethoxide (Et ₃ Al ₂ (OEt) ₃ ) and 0.014 mmol of methyl methacrylate was added, ethylene was supplied, and the ethylene gas concentration in the gas phase was changed to
Copolymerization of propylene and ethylene was carried out at 55 ° C. for 120 minutes so that the concentration became 15 mol%. The ethylene gas concentration during this period is 15 m while checking with a gas chromatograph.
ol% was retained. During this time, hydrogen was not used. After the polymerization was completed, unreacted monomers were purged to obtain a particulate polymer. No adhesion was observed in the polymerization tank or on the stirring blade. The yield was 140 g, and the polymerization ratio of all polymers was 7
It was 370 g-polymer / g-titanium trichloride.

Further, as a result of separately polymerizing only propylene, titanium trichloride 1 was obtained at 70 ° C. for 60 minutes.
1030 g of propylene was polymerized per g.
As a result, the polybutene component in the block copolymer was 0.
It can be seen that 19 wt% and polypropylene component are 14 wt%. The results are shown in Table 1.

Production Examples 2 and 3 In the polymerization of 1-butene of Production Example 1, the same operation as in Production Example 1 was performed except that the polymerization amount of 1-butene was 3 g and 50 g per 1 g of titanium trichloride. went. The results are shown in Table 1.

Production Examples 4 and 5 In the propylene polymerization of Production Example 1, the same operation as in Production Example 1 was performed except that propylene was polymerized at 60 ° C. for 10 minutes and 60 ° C. for 30 minutes. In a separate polymerization experiment, the polymerization ratio of propylene at this time was 240 g-P each.
P / g-TiCl ₃ and 540 g-PP / g-TiCl ₃
Met. The results are shown in Table 1.

Production Example 6 In the same manner as in Production Example 1, except that the polymerization of propylene in Production Example 1 was carried out at 70 ° C. for 5 hours and the copolymerization of propylene and ethylene was performed at 55 ° C. for 60 minutes. The operation was performed. In a separate polymerization experiment, the polymerization ratio at this time was
It was _{5100g-PP / g-TiCl 3} . The results are shown in Table 1.

Comparative Production Example 1 The same operation as in Production Example 1 was carried out except that 1-butene was not polymerized in the main polymerization of Production Example 1. The results are shown in Table 1.

Comparative Production Example 2 The same operation as in Production Example 1 was carried out except that in the main polymerization of Production Example 1, the polymerization of 1-butene was changed to 600 g per 1 g of titanium trichloride. The results are shown in Table 1.

Comparative Production Example 3 The propylene polymerization of Production Example 1 was polymerized at 70 ° C. for 5 hours,
The same operation as in Example 1 was carried out except that the polymerization of ethylene propylene was carried out at 55 ° C. for 15 minutes. The results are shown in Table 1.

[0072]

[Table 1]

[0073]

[Table 2]

Examples 1 to 9 To 30 kg of the block copolymer obtained in Production Example 1, 1,3-bis- (t-butylperoxyisopropyl) benzene as an organic peroxide and divinylbenzene as a crosslinking agent were added. Further, azodicarbonamide was added as an organic foaming agent in a ratio shown in Table 2, and an antioxidant was added in an amount of 0.
After adding 1 phr and mixing with a Henschel mixer for 3 minutes, the mixture was melt-kneaded with a φ65 mm single screw extruder at 230 ° C. to obtain pellets. The MI of the cleaning agent added with the organic foaming agent is the MI before addition of the organic foaming agent.

Next, the screw diameter is 28 mm and the injection capacity is 5
Using an injection molding machine with 6g and a mold clamping force of 50TON, and a flat plate mold with an injection weight of 23g including spool and runner,
First, about 20 flat plates were formed by introducing black polypropylene having MI of 10 g / 10 min. After confirming that the black polypropylene was automatically discharged from the injection molding machine, the molding machine cleaning agent obtained above was charged to continuously mold flat plates. At this time, the number of shots until the black color of the flat plate disappeared completely (the number of blackened shots) is shown in Table 2.

Next, after confirming that the cleaning agent for the molding machine was automatically discharged from the injection molding machine, transparent polypropylene having MI of 10 g / 10 min was added to continuously mold flat plates. At this time, Table 2 also shows the number of shots (the number of de-cleaning agent shots) until the molding machine cleaning agent is completely consumed.

Examples 10 to 14, Comparative Examples 1 to 5 The polymers produced in Production Examples 2 to 6 and Comparative Production Examples 1 to 3 were used as a molding machine cleaner in the same manner as in Example 1, and the results were used. The results are shown in Table 2.

[0078]

[Table 3]

Claims (1)

[Claims] 1. A block copolymer comprising a polybutene component, a polypropylene component, and a propylene-ethylene random copolymer component, wherein the polybutene component is 0.01 to
5% by weight, polypropylene component 1 to 70% by weight, propylene-ethylene random copolymer component 25 to 98% by weight.
99% by weight, and the propylene-ethylene random copolymer component contains 15 to 80 ethylene-based monomer units.
A molding machine cleaner comprising a block copolymer containing mol% and 85 to 20 mol% of a propylene-based monomer unit and having an MI of 0.01 to 6 g / 10 min.