JPH10156830A - Manufacture of polyolefin molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the coloring a molding due to amine compounds without deteriorating the antistatic properties of the molding. SOLUTION: In the first method for making a polyorefin molding, the molding is obtained from a composition containing 100 pts.wt. of polyolefin containing a recycled resin, 0.01-1 pt.wt. of a amine compound (antistatic agent), and 0.01-0.5 pt.wt. of at least one component selected from aliphatic acid metal salt, hydrotalate group, and metal carbonate. In the second method, the molding is obtained by molding a polylefin composition containing 100 pts.wt. of polyolefin, 0.01-1 pt.wt. of the amine compound, and 0.01-0.05 pt.wt. of at least one component selected from aliphatic acid metal salt, hydratorcite group, and metal carbonate at a resin temperature exceeding the melting point of the polyolefin (the maximum melting point when two or more melting points exist) plus 100 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polyolefin resin molded product, and more particularly, to a method for producing a polyolefin resin molded product from a polyolefin resin composition containing a (hydroxyalkyl) alkylamine as an antistatic agent without impairing the antistatic property. The present invention relates to a method for producing a polyolefin resin molded article which can prevent coloring caused by a (hydroxyalkyl) alkylamine.

[0002]

BACKGROUND OF THE INVENTION When molding films, filaments, containers, and other molds from polyolefin resins by extrusion molding, injection molding, blow molding, etc., the raw material polyolefin is used for the purpose of preventing dust from adhering to molded products. It is conventionally known to incorporate an antistatic agent into a resin.

As such antistatic agents, various compounds such as fatty acid amides, (hydroxyalkyl) alkylamines such as alkyldiethanolamine, and fatty acid glycerides are known.

However, conventionally, molding of polyolefin resin has been performed at a resin temperature of 100 ° C. or lower, which is the melting point of polyolefin resin. However, in order to increase the productivity of a molded product of polyolefin resin, the resin temperature during molding must be further increased. When performing high-speed molding by increasing the flowability of the raw material polyolefin resin, or by mixing the recycled polyolefin resin obtained by collecting defective moldings and burrs of the molded product with a new raw material polyolefin resin and performing molding In this case, there is a problem that a molded article obtained from a polyolefin containing (hydroxyalkyl) amine is colored yellow.

[0005] On the other hand, it has been conventionally known that an amine compound and a fatty acid metal salt are blended into a polyolefin resin to impart antistatic properties. For example, JP-A-56-84
No. 737 discloses a method for producing a polypropylene biaxially stretched film from a polypropylene resin composition containing a fatty acid amide and a fatty acid monoglyceride in addition to a higher alkyl diethanolamine and a fatty acid metal salt,
It is said that whitening of the film can be prevented.
According to the examples described in this publication, the polypropylene resin composition is formed into a film at a forming temperature of 250 ° C. Although the molding temperature is not limited to the resin temperature, even if this molding temperature is assumed to be the resin temperature, the melting point of the homopolypropylene is 160 to 170 ° C., and the melting point of the homopolypropylene is 155 even if considered as a random polypropylene. ° C, the resin temperature during molding in the examples described in this publication is (melting point of polypropylene resin + 100)
It is below ° C.

JP-A-56-133347 discloses a polyolefin resin composition in which a (hydroxyalkyl) alkylamine and a metal salt of Group Ia of the periodic table are mixed with a non-demineralized polyolefin resin. ing. In that example, polypropylene was molded at a molding temperature of 230 ° C,
That is, film forming is performed at a resin temperature of (melting point of polypropylene resin + 100) ° C. or less.

Japanese Patent Application Laid-Open No. 7-247385 discloses a polyolefin resin composition obtained by blending a betaine compound, a fatty acid metal salt and / or hydrotalcite with a (hydroxyalkyl) alkylamine in a polyolefin resin. It has been disclosed. In the example, the polypropylene resin composition was molded at a molding temperature of 260 ° C.
That is, a film is formed at a resin temperature of (melting point of polypropylene resin + 100) ° C. or less, and a polyolefin resin composition having excellent antistatic properties in both quick action and durability and generating no white powder is provided. And

The above-mentioned JP-A-56-84737, JP-A-56-133347 and JP-A-7-247
No. 385 discloses that the resin temperature during molding is equal to or lower than the melting point of the polyolefin resin + 100 ° C., and that there is no description that a recycled polyolefin resin is used as a raw material polyolefin resin.

[0009]

An object of the present invention is to solve the problems associated with the prior art as described above, and to provide a polyolefin resin composition containing a (hydroxyalkyl) alkylamine as an antistatic agent. It is an object of the present invention to provide a method for producing a polyolefin resin molded article, which can prevent coloring caused by a (hydroxyalkyl) alkylamine without impairing the composition.

[0010]

SUMMARY OF THE INVENTION A first method for producing a polyolefin resin molded article according to the present invention comprises the steps of: adding 100 parts by weight of a polyolefin resin (A) containing a recycled resin;

[0011]

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Wherein R ¹ is an aliphatic hydrocarbon group having 8 to 22 carbon atoms, and R ² and R ³ are each independently a divalent aliphatic hydrocarbon group having 2 to 4 carbon atoms. A hydrogen atom, R ⁴ is a hydrogen atom or an acyl group of an aliphatic hydrocarbon having 8 to 22 carbon atoms, and m and n are each an integer of 1 to 10]. )
0.01 to 1 part by weight and at least one component (C) selected from fatty acid metal salt (C1), hydrotalcites (C2) and metal carbonate (C3) 0.01 to 0.5
A molded article is produced from the polyolefin resin composition containing the first and second parts by weight.

The polyolefin resin (A) containing the recycled resin is preferably all polyethylene. The fatty acid metal salt (C1) or the metal carbonate (C1)
3) is preferably a metal salt of Ca, Mg and Zn.

A second method for producing a polyolefin resin molded article according to the present invention is a method for producing a polyolefin resin (A)
00 parts by weight, 0.01 to 1 part by weight of the amine compound (B) represented by the formula [I], a fatty acid metal salt (C1),
Hydrotalcites (C2) and metal carbonates (C
0.01 at least one component (C) selected from 3)
From 0.5 to 0.5 parts by weight of a polyolefin resin composition at a resin temperature exceeding 100 ° C. + the melting point of the polyolefin resin (A) (the highest melting point if there are a plurality of melting points). Features.

The polyolefin resin (A) includes:
Polyethylene is preferred. The metal salt of a fatty acid (C1) or the metal salt of a carbonate (C3) is preferably a metal salt of Ca, Mg and Zn.

[0016]

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the method for producing a polyolefin resin molded product according to the present invention will be specifically described.

Polyolefin resin (A) The polyolefin resin (A) used in the present invention comprises ethylene, propylene, 1-butene, 3-methyl-1-butene,
Homo- or copolymers of α-olefins such as methyl-1-pentene, and ethylene / vinyl acetate copolymers
It is a vinyl ester copolymer, a copolymer of ethylene and an unsaturated carboxylic acid or a derivative thereof, or the like, and may be any polyolefin prepared by a known method. Specific examples of the polyolefin resin (A) include polyethylene (high pressure polyethylene, medium / low pressure polyethylene, linear low density polyethylene, etc.), polypropylene, poly 1-butene, and the like. A mixture of different resins may be used. Among such polyolefins, polyethylene and polypropylene are particularly preferred.

[0018] The polyolefin resin used in the present invention may or may not have the catalyst residue resulting from its production process removed. In particular, a transition metal compound, an organoaluminum compound, a polyolefin obtained without a catalyst residue removal step using a Ziegler-type catalyst or the like having a halogen-containing compound such as a halogen-containing magnesium compound as a catalyst component or a catalyst carrier component was used. In this case, the effect of the present invention is remarkably exhibited.

In the present invention, non-standard defective products, defective products called burrs, and other once molded polyolefin resin molded products generated in the process of manufacturing molded products can be used as recycled products.

In the first method for producing a polyolefin resin molded article according to the present invention, a polyolefin resin (A) containing a recycled resin is used. In this polyolefin resin, a recycled resin can be blended in an amount of 60% by weight or less, preferably 40% by weight or less, more preferably 30% by weight or less.

In the second method for producing a polyolefin resin molded article according to the present invention, the polyolefin resin (A) which is not mixed with a recycled resin is usually used. Of course, the recycled resin is mixed within the above range. A polyolefin resin (A) may be used.

Amine Compound (B) The amine compound (B) used in the present invention is an antistatic agent and is represented by the following formula [I].

[0023]

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In the formula [I], R ¹ has 8 to 22 carbon atoms.
R ² and R ³ are each independently a divalent aliphatic hydrocarbon group having 2 to 4 carbon atoms, and R ⁴ is a hydrogen atom or a carbon atom having 8 to 8 carbon atoms. 22 is an acyl group of an aliphatic hydrocarbon, and m and n are each an integer of 1 to 10.

Examples of the amine compound (B) represented by the above formula [I] include N, N-bis (2-hydroxyethyl) laurylamine [other name, lauryldiethanolamine], N, N-bis (2-hydroxyhydroxyethyl) myristylamine [alias, myristyldiethanolamine], N, N-bis (2-hydroxyhydroxyethyl) palmitylamine [alias, palmityldiethanolamine], N, N-bis (2-hydroxy N, N-bis (2-hydroxyethyl) alkylamines such as hydroxyethyl) stearylamine [alias, stearyldiethanolamine], N, N-bis (2-hydroxyhydroxyethyl) oleylamine [alias, oleyldiethanolamine]; N , N-bis (pentapolyoxyethylene) alkylamine and the like.

These amine compounds (B) can be used alone,
Alternatively, two or more kinds can be used in combination. The amine compound (B) is a polyolefin resin (A) 1
It is used in an amount of 0.01 to 1 part by weight, preferably 0.1 to 0.5 part by weight, based on 00 parts by weight. When the amine compound (B) is used in the above ratio, a molded article having sufficiently excellent antistatic properties and having no stickiness due to bleed out of the antistatic agent can be provided. Moreover, the cost increase due to the amine compound (B) is not a problem because the amount of the compound used is small.

Among the commercially available antistatic agents, there are those in which other substances such as alcohol and silicic acid are mixed in addition to these amine compounds, that is, the amine compound represented by the formula [I]. Such an antistatic agent can be used as long as it contains the amine compound represented by the formula [I].

Component (C) Component (C) used in the present invention comprises a fatty acid metal salt (C).
1), at least one of hydrotalcites (C2) and metal carbonate (C3).

<Fatty Acid Metal Salt (C1)> The fatty acid metal salt (C1) used in the present invention is represented by the following formula (R ⁵ COO) _n M ¹ .

In the above formula, R ⁵ has 12 carbon atoms.
To 22 hydrocarbon groups, preferably a hydrocarbon group having 18 carbon atoms. N is 1 or 2, and M
¹ represents an alkali metal such as Li or Na, an alkaline earth metal such as Ca or Mg, or a transition metal such as Zn.

As the fatty acid metal salt (C1) represented by the above formula, specifically, calcium myristate, zinc myristate, calcium palmitate, calcium stearate, zinc stearate, calcium oleate,
And zinc oleate.

These fatty acid metal salts (C1) can be used alone or in combination of two or more. The fatty acid metal salt (C1) can be used in combination with hydrotalcite (C2) and / or metal carbonate (C3).

The fatty acid metal salt (C1) is used in an amount of 0.01 to 0.5 part by weight, preferably 0.02 to 0.4 part by weight, based on 100 parts by weight of the polyolefin resin (A). When the fatty acid metal salt (C1) is used in the above ratio, coloring of the molded article by the amine compound (B) can be prevented, and the effect of preventing coloring is sufficiently improved. In addition, the cost increase due to the fatty acid metal salt (C1) does not pose a problem because the amount of the metal salt is small.

It is preferable to use a fatty acid metal salt (C1) in order to impart lubricity to the polyolefin resin (A) and improve molding processability such as reduction of extrusion torque.

<Hydrotalcites (C2)> The hydrotalcites (C2) used in the present invention are double salt compounds represented by the following formula and may be natural products,
It may be a synthetic product.

(M ²⁺ ) _1-x Al _x (OH) ₂ (A ⁿ⁻ ) _{2 / n} · mH ₂ O wherein x is a value satisfying a relationship of 0 <x ≦ 0.5. There, m is a real number, M ²⁺ is, Mg, a Ca or Zn, a ^n-is the n-valent anion. ] In the present invention, in particular M ²⁺ is Mg, A ^n-is CO ₃ ^2- is a synthetic desirable.

The hydrotalcites (C2) can be used alone or in combination of two or more. Further, the hydrotalcites (C2) can be used in combination with the fatty acid metal salt (C1) and / or the metal carbonate (C3).

The hydrotalcite (C2) is used in an amount of 0.01 to 100 parts by weight of the polyolefin resin (A).
0.5 parts by weight, preferably 0.02 to 0.4 parts by weight. When the hydrotalcites (C2) are used in the above ratio, the amine compound (B) of the molded article
Can be prevented, and the effect of improving the prevention of coloring is sufficient. Moreover, hydrotalcites (C2)
Cost increase is not a problem because the amount of use is small. In particular, in the case of hydrotalcites (C2), there is a feature that even if the blending amount is smaller than that of the fatty acid metal salt (C1), the coloring prevention performance is exhibited.

Such hydrotalcites (C2)
By using, it is possible to improve the effect of preventing rusting of the molding machine due to chlorine in the catalyst used for the polymerization of the polyolefin.

In particular, in order to improve both the anti-coloring property and the moldability with a small amount of compounding, a fatty acid metal salt (C
It is preferable to use both 1) and the hydrotalcites (C2). In this case, the total compounding amount of the fatty acid metal salt (C1) and the hydrotalcites (C2) is 0.01 to 0.1 with respect to 100 parts by weight of the polyolefin resin (A).
3 parts by weight, preferably in the range of 0.01 to 0.2 parts by weight, and the weight ratio of the hydrotalcites (C2) to the fatty acid metal salt (C1) is 1/5 to 1/3. It is preferable that it is within the range.

<Metal Carbonate (C3)> Examples of the metal carbonate (C3) used in the present invention include lithium carbonate, sodium carbonate, potassium carbonate, calcium carbonate, zinc carbonate and the like.

These metal carbonates (C3) can be used alone,
Alternatively, two or more kinds can be used in combination. Further, the metal carbonate (C3) can be used in combination with the fatty acid metal salt (C1) and / or the hydrotalcite (C2).

The metal carbonate (C3) is used in an amount of 0.01 to 0.5 part by weight, preferably 0.02 to 0.4 part by weight, based on 100 parts by weight of the polyolefin resin (A). When the metal carbonate (C3) is used at the above ratio, coloring of the molded article due to the amine compound (B) can be prevented, and the effect of improving coloring prevention is sufficient.

Polyolefin Resin Composition The polyolefin resin composition used in the present invention can be prepared by a conventionally known method. For example, the above components are mixed and melted using a Henschel mixer, an extruder or the like. It can be obtained in the form of pellets by granulating with a pelletizer.

In the polyolefin resin composition used in the present invention, if necessary, a compounding agent such as a lubricant, an anti-blocking agent, a processing aid, a nucleating agent, a cross-linking agent, a foaming agent and an antioxidant may be added. It can be contained within a range that does not impair the object of the invention.

Method for Producing Polyolefin Resin Molded Article The first method for producing a polyolefin resin molded article according to the present invention comprises a polyolefin resin (A) containing the above-mentioned recycled resin, an amine compound (B), and a fatty acid metal salt ( C
1) A molded article is formed from a polyolefin resin composition containing at least one component (C) selected from hydrotalcites (C2) and metal carbonates (C3).

That is, in the first method for producing a polyolefin resin molded product according to the present invention, defective polyolefin resin molded products, burrs, and the like generated during molding are collected, and the recovered polyolefin is converted into a new raw material polyolefin. The resin is mixed and molded. According to this production method, even if a recycled polyolefin resin is used, it is possible to prevent the coloring caused by the amine compound (B).

The second method for producing a polyolefin resin molded product according to the present invention is characterized in that the polyolefin resin (A)
, Amine compound (B), fatty acid metal salt (C1), hydrotalcites (C2) and metal carbonate (C3)
The resin temperature of the polyolefin resin composition at the time of molding from the polyolefin resin composition containing at least one component (C) selected from the group consisting of: ) + 100 ° C., especially the melting point of polyolefin resin + 105 ° C.
The temperature is set to be higher than the above, and a molded article is manufactured.

The resin temperature of the polyolefin resin composition is as follows:
Although the resin temperature measured at any place in the molding machine may be used, from the viewpoint of ease of measurement of the resin temperature, for example, in the case of extrusion molding or blow molding, by measuring the resin temperature immediately after coming out of the die, The index may be used.

Depending on the polyolefin resin (A), D
When the melting point is measured by SC (differential scanning calorimeter), a plurality of melting points (melting peaks) may be measured. In this case, the highest melting point is used as a reference.

The method for producing a polyolefin resin molded product according to the present invention can be used to form, for example, a film, a sheet,
Bottles, filaments, pipes, foams, injection molded articles, etc. can be manufactured.

[0052]

According to the method for producing a polyolefin resin molded article of the present invention as described above, the amine compound (B) represented by the above formula [I] can be used without impairing the antistatic property of the molded article. It is possible to prevent the resulting colored product from being colored.

[0053]

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

The components used in Examples, Comparative Examples and Reference Examples are as follows. Polyolefin resin (1) High-density polyethylene (HDPE1): pelletized high-density polyethylene MFR (ASTM D 1238, 190 ° C, load 2.16) polymerized using a Ziegler-type catalyst containing a halogen-containing magnesium compound as a catalyst carrier component. kg) = 0.36
g / 10 min Density = 0.958 g / cm ³ Melting point = 132 ° C (2) Recycled high-density polyethylene (abbreviated as recovered resin); pelletized recycled product of HPDE1 (pelleting conditions are the same as those of HDPE1) ) Antistatic agent (1) lauryldiethanolamine (amine-based antistatic agent; a) (2) stearyldiethanolamine (amine-based antistatic agent; b) (3) stearyl monoglyceride (glyceride-based antistatic agent; g) fatty acid metal salt ( 1) Calcium stearate (c) (2) Zinc stearate (d) Metal carbonate (1) Calcium carbonate (e) Hydrotalcites (1) Hydrotalcite (f)

[0055]

Examples 1 to 8, Comparative Examples 1 to 3 and Reference Examples 1 to 4 Using an extruder having a screw diameter of 40 mmφ and an L / D = 28 uniaxial full-flight screw, the high density shown in Table 1 was used. Polyethylene (HDPE1) and additives
Compounded and melt-kneaded at the compounding ratios shown in Table 1, extruded the polyethylene resin composition into strands having a diameter of about 3 mm at the resin temperature shown in Table 1, cooled in a cooling water tank and cut into lengths of about 5 mm with a cutter. To obtain a sample.

The obtained sample was measured for a diameter of 10 cm and a depth of 3 c.
m of glass until it was full, and the b value was measured with a Kurabo Industries spectrophotometer (model color 7). If the b value is in the range of -2 to +2, the coloring prevention effect is sufficient, and the result is judged to be acceptable.

The results are shown in Table 1.

[0058]

[Table 1]

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 23/00 C08L 23/00 23/06 23/06

Claims (4)

[Claims] (1) 100 parts by weight of a polyolefin resin (A) containing a recycled resin, and the following formula [I]: [Wherein, R ¹ is an aliphatic hydrocarbon group having 8 to 22 carbon atoms, and R ² and R ³ are each independently a 2 to 4 carbon atom 2
R ⁴ is a hydrogen atom or an acyl group of an aliphatic hydrocarbon having 8 to 22 carbon atoms, and m and n are each an integer of 1 to 10] Amine compound (B) 0.01 to 1 part by weight, fatty acid metal salt (C1), hydrotalcites (C2)
And at least one component (C) selected from metal carbonate (C3) in an amount of 0.01 to 0.5 part by weight to produce a molded article from a polyolefin resin composition. A method for producing a polyolefin resin molded product. 2. The method according to claim 1, wherein the polyolefin resin (A) contains a recycled resin in an amount of 60% by weight or less. 3. The method for producing a polyolefin molded article according to claim 1, wherein the polyolefin resin (A) containing the recycled resin is all polyethylene. 4. A polyolefin resin (A) (100 parts by weight) and the following formula [I]: [Wherein, R ¹ is an aliphatic hydrocarbon group having 8 to 22 carbon atoms, and R ² and R ³ are each independently a 2 to 4 carbon atom 2
R ⁴ is a hydrogen atom or an acyl group of an aliphatic hydrocarbon having 8 to 22 carbon atoms, and m and n are each an integer of 1 to 10] Amine compound (B) 0.01 to 1 part by weight, fatty acid metal salt (C1), hydrotalcites (C2)
And at least one component (C) selected from the group consisting of metal carbonate (C3) and 0.01 to 0.5 parts by weight of a polyolefin resin (A). (If there are more than one, the highest melting point) +1
A method for producing a molded article of a polyolefin resin, which comprises producing a molded article at a resin temperature exceeding 00 ° C.