JPH07324147A - Production of polyolefin resin composition - Google Patents

Abstract

PURPOSE:To produce a polyolefin resin composition excellent in processability, surface properties and transparency by mixing polytetrafluoroethylene with a dispersing medium powder under high shear to fiberize the polytetrafluoroethylene and mixing the formed fibers with a polyolefin. CONSTITUTION:This process is one for producing a polyolefin resin composition by mixing 100 pts.wt. polyolefin (A) with 0.001-10 pts.wt. polytetrafluoroethylene (B), which process comprises carrying out the mixing by premixing polytetrafluoroethylene (B) with 0.002-100 pts.wt. dispersion medium powder (C) having a mean particle diameter of 0.1-700mum in a (C)/(B) ratio in the range of 100/50 to 100/0.001 under high shear to fiberize the polytetrafluoroethylene (B) and mixing the obtained masterbatch with polyolefin (A).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a polyolefin resin composition. More specifically, polytetrafluoroethylene, a masterbatch composed of a dispersion medium powder and a polyolefin, and, if necessary, a processability obtained by further mixing a nucleating agent or an inorganic filler, a surface property,
The present invention relates to a method for producing a polyolefin resin composition having good transparency and the like.

[0002]

2. Description of the Related Art Conventionally, polyolefin has been widely used for various molded products because it is inexpensive and has excellent physical properties.

However, for example, polypropylene has a low viscosity and a low tension when melted, so that the vacuum formability of the sheet (hereinafter referred to as thermoformability), the calender formability,
It has drawbacks such as poor processability such as blow moldability and foam moldability.

Polyethylene or the like is generally mechanically mixed for the purpose of improving the processability of the polypropylene. However, since the effect of improving the processability is insufficient, a large amount of polyethylene is required and the obtained mixture is obtained. However, there is a drawback in that the rigidity of is reduced. Attempts have also been made to improve the viscosity and tension of molten polypropylene by increasing its molecular weight, but polypropylene with a large molecular weight is difficult to extrude, which is one of the important processing methods. There is a big problem that there is.

Further, it has been proposed to add an uncrosslinked acrylic polymer to polyethylene to improve its processability (US Pat. No. 4,156,703), but the compatibility between the two is insufficient. Also, since the acrylic polymer is not cross-linked, during calendar molding, extrusion molding, etc.
There is a problem that the acrylic polymer separates from polyethylene and adheres to the roll surface of a calender, the die surface of an extruder (hereinafter, this is referred to as plate-out), and the processability and properties are rather deteriorated.

Further, the low rigidity inherent to the above polyolefin,
In addition, an inorganic filler or the like is added for the purpose of improving the decrease in rigidity due to the addition of polyethylene or the like.
It has a low compatibility with polyolefin and has a drawback that the surface property of a molded product, for example, an extruded sheet, is significantly lowered due to poor dispersion.

Conventionally, the core-shell type modifier, which has been widely used as an impact resistance improving agent in polyvinyl chloride resins, can efficiently disperse a rubber component (core layer) having a preset particle diameter. Therefore, it is possible to suppress the decrease in rigidity and improve the impact resistance. However, the non-polar polyolefin has a small compatibility with the core-shell type modifier,
The problem is that it can hardly be used.

Therefore, it has been proposed to add the above-mentioned core-shell type modifier to a polyolefin in the presence of a specific compatibilizing agent (JP-A-3-185037 and US Pat. No. 4,997,884). However, the process of synthesizing the compatibilizing agent is complicated, and there are problems that the use of the compatibilizing agent increases costs and the system becomes complicated.

Attempts have been made to add fibrous polytetrafluoroethylene to a thermoplastic resin to increase melt viscosity and improve processability (US Pat.
(005795)), polytetrafluoroethylene is poorly dispersed in a thermoplastic resin which is a matrix, and the surface properties of a molded product, for example, an extruded sheet, are significantly deteriorated.

As described above, it is the actual situation that a polyolefin resin composition having excellent workability and surface properties has not yet been obtained, and development of such a polyolefin resin composition has been awaited.

[0011]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for producing a polyolefin resin composition comprising polytetrafluoroethylene and polyolefin, which exhibits excellent processability and surface property at the same time.

[0012]

According to the present invention, in adding 0.001 to 10 parts by weight of polytetrafluoroethylene (B) to 100 parts by weight of polyolefin (A), polytetrafluoroethylene (B) and 0 are added. Dispersion medium powder (C) 0.0 having an average particle size of 1 to 700 microns
02 to 100 parts by weight of the dispersion medium powder (C) and polytetrafluoroethylene (B) in the ratio (C) / (B)
Is mixed under high shear in the range of 100/50 to 100 / 0.001 to obtain polytetrafluoroethylene (B).
The present invention relates to a method for producing a polyolefin-based resin composition, which comprises producing a masterbatch by fiberizing the mixture and mixing the masterbatch with the polyolefin (A).

[0013]

ACTION AND EXAMPLE The present invention is based on polyolefin (A)
The present invention relates to a process for adding 0.001 to 10 parts of polytetrafluoroethylene (B) to 100 parts (parts by weight, the same applies hereinafter).

The polyolefin (A) used in the production method of the present invention is a component which acts as a base resin in the polyolefin resin composition (hereinafter also referred to as PO composition) obtained by the production method of the present invention. Since polyolefin is used as the base resin, the composition of the present invention can be molded by a simple and general method such as a calendar molding method, an extrusion molding method, a thermoforming method, a blow molding method, and an injection molding method.
Moreover, the obtained molded product has excellent workability, impact resistance,
It has characteristics of rigidity and surface property.

The polyolefin (A) is a value obtained by measuring the number of grams of molten polymer falling in 10 minutes under a load of 2.16 kg according to the melt flow index (ASTM D1238. 230 ° C. for propylene-based polyolefin. In ethylene-based polyolefin, the value at 190 ° C.) (hereinafter, also referred to as MI) is 10
The following, preferably 5 or less, more preferably 2.5 or less, have high melt tension and excellent workability, and have good kneading and dispersibility with a masterbatch, an inorganic filler, etc. It is preferable in terms of expression.

Specific examples of the polyolefin (A) include polypropylene, high density polyethylene, low density polyethylene, linear low density polyethylene and poly-1.
-Butene, polyisobutylene, random or block copolymers in all proportions of propylene and ethylene and / or 1-butene, less than 10% (wt%, hereinafter) of diene components in all proportions of ethylene and propylene. Included ethylene-propylene-diene terpolymers, polymethylpentene, copolymers of cyclopentadiene and ethylene or propylene and other cyclic polyolefins, ethylene or propylene and 5
Random, block or graft copolymers with 0% or less of vinyl compounds such as vinyl acetate, methacrylic acid alkyl ester, acrylic acid alkyl ester and aromatic vinyl can be mentioned.

These may be used alone or in admixture of two or more.

Among the polyolefins (A), a propylene-based polyolefin obtained by polymerizing a monomer component containing 50% or more, and further 75% or more of propylene or propylene containing 50% or more of propylene. 100 parts of polyolefin and 5 parts of ethylene
Ethylene-based polyolefin containing 0% or more 0.1-1
A mixture of 00 parts is preferable from the viewpoint of exhibiting the effect of the present invention, because it has a high melt tension, excellent processability, and good kneading and dispersibility with a masterbatch, an inorganic filler and the like.

Further, among the above-mentioned polyolefins (A), when the polyolefin (A) is at least one selected from polypropylene, ethylene propylene random copolymer and ethylene propylene block copolymer, the versatility is high. From the viewpoint of low cost, the polyolefin (A) is 100 parts by weight of a propylene-based polyolefin composed of at least one selected from polypropylene, an ethylene-propylene random copolymer and an ethylene-propylene block copolymer, and low-density polyethylene, When it is a mixture with 0.1 to 100 parts of an ethylene-based polyolefin consisting of at least one selected from linear low-density polyethylene and high-density polyethylene, it is similarly versatile and low-cost and has a melt tension of high From the viewpoint of workability is excellent.

In the production method of the present invention, polytetrafluoroethylene (hereinafter,
(Also referred to as PTFE (B)) is used. PTFE
(B) is a component for modifying the polyolefin (A) to improve the processability of the PO composition obtained by the production method of the present invention.

The PTFE (B) is not particularly limited as long as it is made into fibers by applying a shearing force,
Examples include powders produced by aggregating an emulsion dispersion of high molecular weight polytetrafluoroethylene obtained by emulsion polymerization, powders produced from high molecular weight polytetrafluoroethylene obtained by suspension polymerization, etc. .

Among them, a powder produced by aggregating an emulsion dispersion of high molecular weight polytetrafluoroethylene obtained by an emulsion polymerization method or the like is preferable from the viewpoint that it is easily fiberized by shearing force. Even if the powder of polytetrafluoroethylene is not fibrous due to the difference in the synthesis method, it does not exhibit the effect of improving the workability due to the increase of tension during melting and is not used in the present invention.

The average particle size of PTFE (B) is 100 to 700 μm, preferably 300, from the viewpoint of mixing and dispersing the dispersion medium powder (C) by masterbatch.
.About.600 microns, more preferably 400 to 500 microns.

A commercially available raw material for obtaining the fibrous PTFE (B) is Polyflon TF manufactured by Daikin Industries, Ltd.
Typical examples include E-F103 and F104, and Teflon TFE-6J and 6C-J manufactured by Mitsui DuPont Co., Ltd.

In the present invention, PTFE (B) is contained in an amount of 0.001 to 10 parts based on 100 parts of the polyolefin (A). When PTFE (B) is less than 0.001 part, the workability improving effect is not sufficient, and when it exceeds 10 parts, versatility such as low cost is impaired. From this point P
The content of TFE (B) is preferably 0.005 to 5 parts, more preferably 0.005 to 3 parts.

PTFE is added to the polyolefin (A).
In adding (B), the production method of the present invention is
(B) and 0.002 to 100 parts of the dispersion medium powder (C) having an average particle diameter of 0.1 to 700 μm, and the ratio (C) / PTFE (B) of the dispersion medium powder (C) /
(B) is mixed in advance in a range of 100/50 to 100 / 0.001 under high shear, PTFE (B) is made into fibers to prepare a masterbatch, and the masterbatch and polyolefin (A) are mixed. It is characterized by doing.

The dispersion medium powder (C) is a PO composition obtained by the process of the present invention by effectively dispersing and fiberizing polytetrafluoroethylene and also modifying the polyolefin (A) itself. It is a component for improving the surface properties and the like of the obtained molded product and for improving the processability and the like.

The dispersion medium powder (C) is not particularly limited as long as it fulfills the above-mentioned role, and examples thereof include core-shell graft copolymers, polyolefin powders, inorganic powders and organic powders. They can be used alone or in combination of two or more. Among the dispersion medium powders, the core-shell graft copolymer is a dispersion of the dispersion medium powder (C) itself in the polyolefin (A) from the viewpoints of dispersibility of polytetrafluoroethylene and impact resistance of the obtained molded product. Polyolefin powder is preferable from the viewpoints of properties and low cost.

The dispersion medium powder (C) has an average particle size of 0.1 to 700 μm. When the average particle size is less than 0.1 μm or exceeds 700 μm, polytetrafluoroethylene is sufficient. The fibers are not made into fibers, and polytetrafluoroeletin lumps remain in the molded product from the obtained PO composition, and the surface property deteriorates. Further, the workability improving effect is also insufficient. From the above viewpoint, it is preferable that the minimum value of the average particle diameter is 50 μm, further 100 μm, and the maximum value is 500 μm, further 300 μm.

The average particle size of the dispersion medium powder (C) is such that Tyler meshes of about 6 different sizes are stacked in descending order of mesh size, and a powder dispersed in water using a surfactant is poured onto the Tyler meshes, and each mesh is passed through. Although it is calculated from the weight ratio of the accumulated powder by a particle size diagram, it can be measured by other general powder measuring methods.

The average particle size of the dispersion medium powder (C) is 0.1
There is no particular limitation on the method for adjusting the particle size to 700 microns, but generally, any method for controlling the particle size of the powder, such as agglomeration, crushing, and sieving, can be used. For example, in the case of core-shell graft copolymer, the particle size of powder can be controlled by the agglomeration method. In the case of a polyolefin powder, a powder having a suitable particle size can be obtained by controlling the particle size at the time of polymerization and the conditions at the time of freeze-grinding. In the case of inorganic powder, there are methods such as crushing and sieving.

The dispersion medium powder (C) is made of PO
From the viewpoint of improving the transparency of the composition, the refractive index of the dispersion medium powder (C) is preferably selected so as to be substantially the same as the refractive index of the polyolefin (A).

The phrase "substantially the same refractive index" means that the difference in refractive index is 0.02 or less, but 0.01 or less, more preferably 0.005 or less is the PO composition. It is preferable in that the transparency is suppressed.

The term "refractive index" as used herein is described in, for example, Polymer Handbook 3rd edition (John Wiley & Sons. Inc. 1989) and the like. As the ratio, a value calculated proportionally by the weight fraction of each monomer is used.

The core-shell polymer used in the present invention (hereinafter,
The core-shell body is also a molding obtained from the PO composition obtained by the production method of the present invention by effectively dispersing and fiberizing PTFE (B) and also modifying the polyolefin (A) itself. It is a component used to improve the impact resistance and surface properties of the body as well as the workability.

The core-shell body refers to one obtained by graft-copolymerizing a shell component in the presence of a crosslinked rubber-like polymer forming a core layer. The core-shell body has impact resistance such as polyolefin and polyvinyl chloride. It may be one generally used for improvement. Among the above core shells, from the viewpoint of heat coloring of the molded product made of the PO composition, which does not undergo thermal deterioration at the molding processing temperature of the polyolefin (A).

The core-shell powder can be controlled to have a particle size at the time of agglomeration, and it is easy to obtain the powder having the particle size suitable for the present invention. Commercially available core-shell type modifiers are Kanefuchi Chemical Co., Ltd. product names: Kane Ace B, Kane Ace M, Kane Ace FM
And the like are preferred.

In the present invention, those having a refractive index substantially the same as that of the polyolefin (A) are preferably used from the viewpoint of improving the transparency of the PO composition. In this case, the cross-linked rubber-like polymer to be the core and the graft monomer to be the shell are selected and synthesized so that the refractive index of the core-shell graft copolymer is substantially the same as that of the polyolefin (A). It

For example, as the core-shell graft copolymer having substantially the same refractive index as polypropylene, 50 parts of cross-linked polybutadiene rubber obtained by emulsion polymerization and 50 parts of methyl methacrylate are graft-copolymerized, 70% n-butyl acrylate and 30 styrene
% Of allyl methacrylate to 70% of cross-linked acrylic rubber obtained by emulsion polymerization, and graft-copolymerized with a monomer component of 27 parts of methyl methacrylate and 3 parts of styrene. Some of them are made.

The polyolefin powder used in the present invention is a PO composition obtained by the production method of the present invention by effectively dispersing and fiberizing PTFE (B) and also modifying the polyolefin (A) itself. It is a component used for improving the surface properties and the like of the obtained molded product and for improving the processability and the like.

Specific examples of the polyolefin powder include polypropylene, high density polyethylene,
Low density polyethylene, linear low density polyethylene, poly-
1-butene, polyisobutylene, random or block copolymers of propylene with ethylene and / or 1-butene in any ratio, ethylene-propylene-containing diene components up to 10% in any ratio of ethylene with propylene. Diene terpolymer, polymethylpentene, copolymer of cyclopentadiene and ethylene or propylene and other cyclic polyolefins, ethylene or propylene and 50% or less of vinyl acetate, methacrylic acid alkyl ester, acrylic acid alkyl ester, Examples thereof include random, block or graft copolymers of vinyl compounds such as aromatic vinyl.

These may be used alone or in admixture of two or more.

Among the above polyolefin powders,
The propylene-based polyolefin obtained by polymerizing the monomer component containing 50% or more of propylene is preferable from the viewpoint of versatility and low cost.

Further, 100 parts of the propylene-based polyolefin containing 50% or more of the propylene and 0.1 part of the ethylene-based polyolefin containing 50% or more of the ethylene.
A mixture of ˜100 parts is preferred because it is also versatile and low cost.

The polyolefin powder is preferably capable of easily mixing the masterbatch obtained by using it with the polyolein (A). If the mixing is not easy, foreign matter tends to remain in the molded product, deteriorating the surface property and transparency. For easy mixing, it is preferable that the polyolefin powder and the polyolefin (A) have the same melt flow index.

Further, it is preferable that the polyolefin powder and the polyolefin (A) have substantially the same composition. In the present invention, those having a refractive index substantially the same as that of the polyolefin (A) are preferably used from the viewpoint of improving the transparency of the PO composition.

The refractive index of typical polyolefin (A) is polypropylene (1.503), high density polyethylene (1.545), low density polyethylene (1.5).
1), linear low density polyethylene (1.52), poly-1
-Butene (1.5125), polymethylpentene (1.
459 to 1.465).

The inorganic powder used in the present invention is PT
By effectively dispersing and fiberizing FE (B),
In addition, it is a component for modifying the polyolefin (A) itself to improve the rigidity, surface property and the like of the molded product obtained from the PO composition obtained by the production method of the present invention, and also improve the processability and the like. .

Specific examples of the inorganic powder used in the present invention include heavy calcium carbonate, light calcium carbonate,
Examples thereof include talc, glass fiber, magnesium carbonate, mica, carion, calcium sulfate, barium sulfate, titanium white, white carbon, carbon black, aluminum hydroxide, aluminum oxide, magnesium hydroxide and fused silica, which may be used alone or in combination with 2 A mixture of two or more species can be used. Among these, heavy calcium carbonate, light calcium carbonate, talc and the like are preferable because they are easily available.

The organic powder used in the present invention includes thermoplastic elastomers represented by block or random copolymers of styrene and butadiene and hydrogenated products thereof, crosslinked elastomers represented by polybutadiene and hydrogenated products thereof. Objects are typical examples. Among these, those having a certain degree of compatibility with the polyolefin (A) and having an average particle diameter of the powder falling within the range of the present invention and freeze-pulverized so as to fall within the range are preferable. .

The dispersion medium powder (C) and PTFE
Ratio (C) / (B) with (B) is 100/50 to 100
The range is /0.001. The ratio is 100/50
If it is less than the above range, the PTFE (B) is not sufficiently formed into fibers and the PTFE (B) is not well dispersed in the polyolefin (A), so that the effect of improving the processability is reduced. When the ratio exceeds 100 / 0.001, for example, 100 parts of the polyolefin (A) and 100 parts of the dispersion medium powder (C) are used.
Even if 100 parts are blended, the number of parts of PTFE (B) is 0.0
It becomes less than 01 parts, and the effect of improving the workability becomes insufficient. From the above viewpoint, the ratio (C) / (B) is preferably 100/40 or more, more preferably 100/30 or more, preferably 100 / 0.005 or less, more preferably 100 / 0.01 or less. is there.

In the present invention, the dispersion medium powder (C) is
0.002-1 for 100 parts of polyolefin (A)
Used in 00 parts. When the dispersion medium powder (C) exceeds 100 parts, the original properties such as heat resistance and rigidity of the polyolefin are impaired, and when it is less than 0.002 part, PT.
FE (B) cannot be effectively dispersed and made into fibers. From this point, the amount of the dispersion medium powder (C) used is 0.
It is preferably in the range of 025 to 70 parts, and more preferably 0.025 to 50 parts.

Dispersion medium powder (C) and PTF
The amount of E (B) used satisfies the above ratio (C) / (B),
Furthermore, it is used by adjusting so as to satisfy the above-mentioned respective usage amounts and preferable usage amounts.

According to the present invention, the PT is premixed under high shear.
Making a masterbatch by fiberizing FE (B) means, for example, dispersion medium powder (C) and PTFE.
This means that PTFE (B) is dispersed and made into fibers by applying a shearing force in advance by a powder mixing method such as stirring (B) with a Henschel mixer or other general agitator.

As another method, the copolymer (B) and PTFE (B) may be melt-kneaded by a single-screw extruder, a twin-screw extruder, a roll kneader, etc.
It means that PTFE (B) is dispersed and fiberized by applying a shearing force to TFE (B) in advance.

The fact that PTFE (B) is fibrillated means that P
The TFE (B) is not particularly limited as long as it is in a fibrous state. For example, in a masterbatch, PTFE
The fiber diameter of (B) is preferably about 2 microns or less, more preferably about 1 micron or less, and further preferably about 0.5 from the viewpoint of efficiently forming a network structure.
It is less than micron. The fiber length cannot be generally determined because it has a network structure, but from the viewpoint of the effect of improving workability by increasing the tension during melting, it is preferably about 3 microns or more, more preferably 5 microns or more, and further preferably about 10. It is more than micron.

The powder mixing method has an effect of low cost, and the melt kneading method has an effect of obtaining a master batch in a pellet form.

Among the above-mentioned stirrers or mixers, a Henschel mixer is preferred.

The operating conditions for preparing a masterbatch by the powder mixing method are not particularly limited as long as PTFE (B) can be mixed under high shear to form fibers.

As a temperature condition for preparing a masterbatch by a powder mixing method using a Henschel mixer or the like, stirring may be carried out at room temperature, and the dispersion medium powder (C) and PTFE (B) are not deteriorated or deteriorated. You may heat and stir at about temperature.

The operating conditions for preparing the masterbatch by the melt-kneading method are not particularly limited as long as PTFE (B) can be mixed under high shear to form fibers.

Further, the powder mixing method and the melt kneading method can be used in combination. For example, after mixing with a Henschel mixer, it is also preferable to prepare a master batch by pelletizing the mixture by melt-kneading it with an extruder or the like.

Next, a PO composition is produced by mixing the obtained masterbatch and the polyolefin (A). The mixing method is not particularly limited, and it can be produced by a usual method such as an extrusion mixing method and a roll mixing method.

The ratio of the masterbatch to the polyolefin (A) is adjusted so that 100 parts of the polyolefin (A) and 0.001 to 10 parts of the PTFE (B) are used.

In the obtained PO composition, P
The fiber diameter of TFE (C) is preferably about 2 μm or less, more preferably about 1 μm or less, and further preferably about 0.5 μm or less from the viewpoint of efficiently forming a network structure. The fiber length cannot be generally determined because it has a network structure, but from the viewpoint of the workability improving effect by increasing the tension during melting, it is preferably about 3 micron or more, more preferably 5 micron or more, and further preferably about 10 micron. It is more than micron.

In the present invention, a specific amount of a dispersion medium powder (C) having a specific particle size and a specific amount of PTFE (B) are mixed in advance under high shear to fiberize PTFE (B) to prepare a masterbatch. By kneading the masterbatch and the polyolefin (A), the fiberization of the PTFE (B) is promoted, and the PTFE (B) is added to the obtained PO composition.
Are evenly dispersed, and the appearance of the molded article obtained from the PO composition is improved. Further, the tension at the time of melting is increased, the take-up property of the sheet during calendering, the drawdown of the molten resin during thermoforming or blow molding, and the open cell formation of cells during foam molding are improved. Processability such as thermoforming, blow molding and foam molding is improved. Further, the discharge amount at the time of extrusion processing and the surface condition of the extruded product such as a sheet and a film are improved, and the extrudability is improved.
Further, by mixing the PTFE (B) with the dispersion medium powder (C), the blocking of the PTFE (B) is improved and the blending with the polyolefin is facilitated.

Furthermore, in the present invention, in the step of mixing the masterbatch and the polyolefin (A) obtained in the present invention, 0.01% of the nucleating agent (D) is added to 100 parts of the polyolefin (A). It also includes a method for producing a PO composition, which is replaced with the step of adding and mixing 2 parts.

The nucleating agent (D) is a component having a function of further improving the transparency, surface property, rigidity and the like of the obtained PO composition. Specific examples of such a nucleating agent include, for example, sodium benzoate, bisbenzylidene sorbitol,
Preferred examples include bis (p-methylbenzylidene) sorbitol, bis (p-ethylbenzylidene) sorbitol, sodium 2,2-methylenebis (4,6-di-tert-butylphenyl) phosphite and the like. These may be used alone or in combination of two or more. Further, talc, TiO2, aluminum hydroxydipara t-butylbenzoate, etc. may be used.

The amount of the nucleating agent used is preferably 0.01 to 2 parts with respect to 100 parts of the polyolefin (A). If the content of the nucleating agent is less than 0.01 part, the effect of improving the transparency and surface property tends to be insufficient, and if it exceeds 2 parts, the effect is saturated and the transparency is rather increased. It may worsen, which is not preferable.

Furthermore, in the present invention, in the step of mixing the masterbatch and the polyolefin (A) obtained in the present invention, an inorganic filler (E) is added to 100 parts by weight of the polyolefin (A) in an amount of 0. It also includes a method for producing a PO composition, which is replaced by the step of adding 1 to 400 parts and mixing.

The inorganic filler (E) is a component having an effect of improving not only the rigidity and processability of the obtained PO composition but also the coating property, printability and heat resistance, and realizing cost reduction. As a typical example of such an inorganic filler (E),
Heavy calcium carbonate, light calcium carbonate, talc, glass fiber, magnesium carbonate, mica, carion, calcium sulfate, barium sulfate, titanium white, white carbon, carbon black, aluminum hydroxide, magnesium hydroxide, fused silica, etc. These can be used alone or in admixture of two or more.
Among these, heavy calcium carbonate, light calcium carbonate, talc and the like are preferable because they are easily available.

The average particle size of the inorganic filler (E) is preferably about 10 microns or less, more preferably about 5 microns or less in order to improve the surface property of the obtained PO composition.

By using 0.1 to 400 parts of the inorganic filler (E), the rigidity and heat resistance of the manufactured PO composition and the molded product obtained from the composition are improved, and calendering is performed. In such cases, the workability such as prevention of sticking to the roll surface is improved, and further cost reduction can be achieved. When the amount of the inorganic filler (E) used is less than 0.1 part, the effect of improving the rigidity and the like is not sufficient.
When it exceeds 0 part, the surface property tends to be deteriorated, which is not preferable. From this point, the amount of the inorganic filler (E) used is preferably 1 to 350 parts, and more preferably 1 to 300 parts.

In addition, when the inorganic filler (E) is mixed, the dispersibility of the inorganic filler (E) is improved and the surface condition of the sheet and film during calendaring or extrusion is improved. . Further, the tension at the time of melting is increased, and the moldability of thermoforming, blow molding, foam molding, etc. is improved. Further, shrinkage and warpage during injection molding are also improved.

In the method for producing the PO composition of the present invention, for example, stabilizers and lubricants may be added, if necessary. Examples of the stabilizer include pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] and triethylene glycol-bis [3- (3-t-butyl-5-methyl). -4-hydroxyphenyl) propionate] and other phenolic stabilizers, tris (monononylphenyl) phosphite, tris (2,4-di-t-butylphenyl) phosphite and other phosphorus stabilizers, and dilauryl 3,3. Representative examples of sulfur stabilizers such as'-thiodipropionate and lubricants include lauric acid, palmitic acid, oleic acid, sodium stearate, calcium, and magnesium salts.

In the present invention, the method for mixing the masterbatch, the polyolefin (A), and optionally the nucleating agent (D), or the inorganic filler (E) is not particularly limited, for example, an extrusion mixing method, It can be produced by a usual method such as a roll mixing method.

Further, after mixing the masterbatch with a part of the polyolefin (A), and depending on the case, the nucleating agent (D) or the inorganic filler (E), the rest is mixed with the polyolefin (A). It is also possible to mix in multiple stages.

The PO composition obtained by the production method of the present invention has greatly improved processability and surface properties, and various molding methods including molding methods which have been difficult with conventional polyolefin resin compositions. Useful moldings can be produced by the method.

The molding method used for the PO composition obtained by the manufacturing method of the present invention is, for example, a calender molding method,
Typical examples include an extrusion molding method, a thermoforming method, a blow molding method, an injection molding method, and a foam molding method.

For example, a film or sheet-shaped molded product can be obtained by calendering or extrusion molding the PO composition obtained by the production method of the present invention. Further, by thermoforming the film or sheet shaped article at a temperature suitable for the polyolefin resin composition used, a thermoformed article can be obtained. Further, for example, injection molding or blow molding can be obtained by injection molding or blow molding the pellets obtained by subjecting the resin composition to extrusion processing. further,
A foam can be obtained by adding a foaming agent to the polyolefin-based resin composition of the present invention and foam-molding using, for example, an extruder.

The production method of the present invention will be described in more detail based on the following examples, but the present invention is not limited thereto.

Examples 1 to 5 and Comparative Examples 1 to 3 Acrylic core-shell graft copolymer (trade name: Kaneace FM, manufactured by Kanebuchi Chemical Industry Co., Ltd.)
Polytetrafluoroethylene powder (trade name: Polyflon TFE-F104, powder produced by aggregating an emulsion dispersion obtained by an emulsion polymerization method, manufactured by Daikin Industries, Ltd.) (hereinafter also referred to as TFE-F) The amount described in Table 1 was stirred at room temperature for 10 minutes at high speed (1,500 rpm) with a Henschel mixer, and at the same time as mixing, shearing was applied to fiberize polytetrafluoroethylene to prepare a masterbatch.

Homopolypropylene pellets (trade name: Hypol-B200, manufactured by Mitsui Petrochemical Industry Co., Ltd., refractive index 1.503, MI: 0. 5 (hereinafter also referred to as high pole B) 100 parts, screw diameter 40
mm, L / D 28 single screw extruder, 200 ° C, 50r
It was extrusion kneaded at pm and pelletized to obtain a PO composition.

The average particle size used in Examples 3 to 24 was 24.
6-micron, 147-micron, 70-micron core-shell graft copolymers were prepared by sieving Kaneace FM using Tyler sieve 60 mesh and 140 mesh. The average particle size of the graft copolymer remaining on the 60 mesh is 246 microns and 1
The particles remaining on 40 mesh had an average particle size of 147 microns, and the particles passing through 140 mesh had an average particle size of 70 microns.

In Comparative Example 2, the masterbatch was not performed, and the predetermined amounts of Hypol B-200 and TFE-F were pelletized in the same manner with the single screw extruder.

The PO composition thus obtained was used to evaluate the processability, impact resistance, flexural modulus, melt tension, roll sheet appearance and melt flow index by the following methods.
The results are shown in Table 2.

(Workability (Drawdown)) The PO composition was roll-kneaded at 200 ° C. for 3 minutes to prepare a roll sheet having a thickness of 1 mm. The obtained two roll sheets are overlapped and press-molded under the condition of 200 ° C. × 30 kg / cm ² × 10 minutes, and then 50 kg / cm ² × 10 at room temperature.
After cooling under the condition of minutes, a sheet having a thickness of 1.5 mm was obtained. A test piece of 300 mm × 400 mm was cut out from this sheet.

The obtained test piece was opened with an opening of 298 mm × 39.
The sheet was fixed with an 8 mm clamp, placed in an open set at 190 ° C., and the sag (also referred to as drawdown) (mm) of the central portion of the sheet was measured for 10 minutes.

(Impact resistance) A 1/4 inch thick test piece was prepared in the same manner as described in the above (workability), and ASTM-D
The Izod impact resistance with notch was measured according to 256.

(Flexural Modulus) Measured in accordance with ASTM-D790.

(Melt tension) Using a PO composition, a caprograph having a diameter of 2 mm and a length of 10 mm manufactured by Toyo Seiki Co., Ltd., 200 ° C., extrusion speed of 20 mm /
Min, the melt tension at a take-up speed of 1 m / min was measured.

(Appearance of Sheet) A PO composition was roll-kneaded at 200 ° C. and press-formed to give a thickness of 1.5 m.
m sheets were produced. The surface condition of the obtained sheet was visually observed and evaluated based on the following evaluation criteria.

(Evaluation Criteria) A: No aggregate of polytetrafluoroethylene is observed.

B: A slight aggregate of fibrous polytetrafluoroethylene is observed.

C: A mass of polytetrafluoroethylene is observed.

(Melt Flow Index) ASTM-
According to D 1238, 230 ° C for propylene-based polyolefins and 190 ° C for ethylene-based polyolefins
It was measured at.

From the results shown in Table 2, the PO compositions obtained in Examples 1 to 5 of the present invention were the same as Comparative Example 2 in which the core-shell graft copolymer was not used, the dispersion medium powder (C) and PTFE.
Compared with the PO composition obtained in Comparative Example 3 in which the ratio (C) / (B) with (B) is 100/100, the drawdown of the sheet, which is an index of processability such as thermoformability and blow moldability. It can be seen that is greatly improved, and the appearance of the sheet is also improved. In addition, in this example, the average particle size is 100.
When the core-shell graft copolymer having a size of micron or more is used, the sheet appearance is particularly excellent.

Further, in order to observe the existence form of polytetrafluoroethylene in polypropylene, the PO composition was cut into an ultrathin section and stained with ruthenium tetraoxide and stained with TE.
It was observed at M (magnification of 10,000). It was observed that the polytetrafluoroethylene had become fibrous. Note that the sample was Kaneace FM in Example 1 so that polytetrafluoroethylene could be easily observed.
25 parts, polytetrafluoroethylene (TFE-F)
In the same manner as in Example 1, except that the content of PO was changed to 0.5
A composition was produced.

[0099]

[Table 1]

[0100]

[Table 2]

Examples 6 to 7 and Comparative Example 4 Instead of the core-shell graft copolymer in Example 1, as shown in Table 3, homopolypropylene freeze-pulverized by Sumitomo Seika Chemicals Co., Ltd. having an average particle size of 250 microns. Floblene QB200 50P, a powder, refractive index 1.50
3 (hereinafter also referred to as Flowbren QB), the average particle size is 1
Hipol B200P, a polypropylene powder manufactured by Mitsui Petrochemical Co., Ltd. having a size of 000 microns, and Snowlight SSS, which is a calcium carbonate manufactured by Maruo Calcium Co., Ltd. having an average particle size of 1.8 microns, are used. The PO composition was obtained and evaluated. The results are shown in Table 4.

When polypropylene freezing pulverized powder (Flowblen QB) having a dispersion medium powder (C) having an average particle diameter within the range of the present invention was used, 250 μm and 1.8 μm calcium carbonate (Snowlight SS) were used.
When S) is used, the drawdown of the seat is greatly improved as in Example 1, and the appearance of the seat is also excellent. On the other hand, when a polypropylene powder having an average particle size of 1000 μm (Hipol B200P), which is out of the range of the present invention, is used, the effect of improving the drawdown of the sheet is small, and the dispersion of polytetrafluoroethylene is poor. , The appearance of the sheet is poor.

[0103]

[Table 3]

[0104]

[Table 4]

Examples 8 to 9 and Comparative Examples 5 to 6 Formulation Examples Containing Nucleating Agent or Inorganic Filler As in Example 1, Flowblene QB (average particle size 250 micron) or Kane Ace FM (average particle size) 18
(0 micron) and TFE-F were rapidly stirred with a Henschel mixer to prepare a masterbatch.

In addition to the obtained masterbatch, Hypol B, the amount of the nucleating agent (Gelol DH (bis (p-methylbenzylidene) sorbitol manufactured by Shin Nippon Rika Co., Ltd.)) or heavy calcium carbonate (trade name: Snowlight SSS Maruo Calcium Co., Ltd.
A PO composition was obtained in the same manner as in Example 1 and evaluated in the same manner as in Example 1. Further, the transparency was evaluated by the following method. The results are shown in Table 6.

(Transparency) A test piece having a thickness of 1.0 mm and a size of 30 mm was prepared in the same manner as described in the above (workability).
It was measured according to ASTM-D-1003. Table 6
In the table, T represents the total light transmittance (%) and Haze represents the turbidity (%).

From the results shown in Table 6, the PO composition obtained in Example 8 of the present invention in which a specific amount of the nucleating agent was further mixed when the masterbatch and the polyolefin (A) were mixed was Hypol. It has the same appearance and transparency as Comparative Example 5 in which B is mixed with only the nucleating agent, and the melt tension is further increased, and the drawdown of the sheet, which is an index of workability, is greatly improved, It can be seen that it has an excellent balance of impact resistance and rigidity.

Similarly, P obtained in Example 9 of the present invention was also mixed with a specific amount of inorganic filler (calcium carbonate).
The O composition has a sheet appearance and rigidity comparable to those of Comparative Example 6 in which only the inorganic filler (calcium carbonate) is mixed with the high pole B, and further the melt tension is increased, which is an index of workability. It can be seen that the drawdown has been greatly improved, and it has an excellent balance of impact resistance and rigidity.

[0110]

[Table 5]

[0111]

[Table 6]

[0112]

According to the manufacturing method of the present invention, the tension when melted in the molding process is large, the retrievability during calendering, the drawdown of the molten resin during thermoforming or blow molding, and the cell during foam molding. It has excellent processability such as calendering, thermoforming, blow molding, foam molding, and the surface condition of extruded products such as sheets and films is improved, resulting in extrudability. It is possible to obtain a polyolefin resin composition having good

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Claims (17)

[Claims] 1. To 100 parts by weight of polyolefin (A),
When adding 0.001 to 10 parts by weight of polytetrafluoroethylene (B), polytetrafluoroethylene (B) and a dispersion medium powder (C) 0.002 to 100 having an average particle diameter of 0.1 to 700 microns. Parts by weight,
The ratio (C) / (B) of the dispersion medium powder (C) and polytetrafluoroethylene (B) is 100/50 to 100.
In the range of 0.001 / 0.001, the mixture is previously mixed under high shear, the polytetrafluoroethylene (B) is made into fibers to prepare a masterbatch, and the masterbatch and the polyolefin (A) are mixed. Process for producing polyolefin resin composition. 2. The method for producing a polyolefin resin composition according to claim 1, wherein the dispersion medium powder (C) is a core-shell graft copolymer. 3. The method for producing a polyolefin resin composition according to claim 1, wherein the dispersion medium powder (C) is a polyolefin powder. 4. The method for producing a polyolefin resin composition according to claim 1, wherein the dispersion medium powder (C) is an inorganic powder. 5. The average particle size of the dispersion medium powder (C) is 50.
The method for producing the polyolefin resin composition according to claim 1, 2, 3 or 4 having a particle size of ˜700 μm. 6. The average particle size of the dispersion medium powder (C) is 10.
The method for producing the polyolefin-based resin composition according to claim 1, which has a size of 0 to 500 microns. 7. The method for producing a polyolefin resin composition according to claim 1, wherein the refractive index of the dispersion medium powder (C) is substantially the same as the refractive index of the polyolefin (A). . 8. The method for producing a polyolefin resin composition according to claim 3, wherein the polyolefin powder has substantially the same composition as the polyolefin (A). 9. A masterbatch and a polyolefin (A)
The mixing of and is to mix the masterbatch and the polyolefin (A) with 0.01 to 2 parts by weight of the nucleating agent (D) with respect to 100 parts by weight of the polyolefin (A). The method for producing the polyolefin resin composition according to 2, 3, 4, 5, 6, 7 or 8. 10. Mixing a masterbatch and a polyolefin (A) is carried out by adding 0.1 to 400 parts by weight of an inorganic filler to the masterbatch and the polyolefin (A), and further to 100 parts by weight of the polyolefin (A). (E)
Are mixed together.
7. A method for producing the polyolefin resin composition according to 7, 8 or 9. 11. The method for producing a polyolefin resin composition according to claim 10, wherein the inorganic filler (E) is calcium carbonate or talc. 12. The polyolefin (A) is a propylene-based polyolefin containing at least 50% by weight of propylene units, 1, 2, 3, 4, 5, 6, 7, 8,
A method for producing the polyolefin-based resin composition according to 9, 10, or 11. 13. The polyolefin (A) comprises 100 parts by weight of a propylene-based polyolefin containing at least 50% by weight of propylene units and at least 50 units of ethylene units.
A mixture of 0.1 to 100 parts by weight of an ethylene-based polyolefin containing 100% by weight,
A method for producing the polyolefin resin composition according to 6, 7, 8, 9, 10 or 11. 14. The polyolefin (A) is at least one selected from the group consisting of polypropylene, an ethylene-propylene random copolymer and an ethylene-propylene block copolymer, 1, 2, 3, 4, 5,
A method for producing the polyolefin resin composition according to 6, 7, 8, 9, 10 or 11. 15. A polyolefin (A) comprising 100 parts by weight of a propylene-based polyolefin comprising at least one selected from the group consisting of polypropylene, an ethylene-propylene random copolymer and an ethylene-propylene block copolymer, and low density polyethylene, 2. A mixture with 0.1 to 100 parts by weight of an ethylene-based polyolefin comprising at least one selected from the group consisting of linear low density polyethylene and high density polyethylene.
The method for producing the polyolefin-based resin composition according to 2, 3, 4, 5, 6, 7, 8, 9, 10 or 11. 16. Polytetrafluoroethylene (B)
Is a powder produced by aggregating an emulsion dispersion obtained by an emulsion polymerization method.
A method for producing the polyolefin-based resin composition according to 6, 7, 8, 9, 10, 11, 12, 13, 14 or 15. 17. The method for producing a masterbatch is a stirring and mixing method using a Henschel mixer.
4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 1
A method for producing the polyolefin resin composition according to 4, 15, or 16.