JP4889136B2 - Propylene resin composition - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a resin composition comprising a propylene polymer, and more particularly to a resin composition comprising a propylene polymer having excellent surface scratch resistance.
[0002]
[Prior art]
Polypropylene is used in a wide range of fields such as household appliances, housing equipment, household goods and automobiles, taking advantage of its excellent heat resistance and chemical resistance and being easy to mold and recycle.
[0003]
In recent years, there has been a demand for development of a member that is not easily scratched due to an increase in consumer-oriented high-quality and aesthetic appearance. In order to solve this problem, a method of adding a lubricant to polypropylene, a method of performing a hard coat treatment on the surface of the member, a method of applying a coating treatment with a substance having a low surface energy such as polyester on the surface of the member, and the like are employed.
[0004]
However, in the method of adding a lubricant, the effect is low and there is also a problem in sustainability. In the method of coating with a hard coat treatment or a substance having a low surface energy, complicated procedures such as painting, drying, and curing are involved. There was a problem in the necessity of the process and the adhesion between the substrate and the coat or coating film.
[0005]
[Problems to be solved by the invention]
Therefore, the present invention does not have the above-mentioned problems, and has excellent scratch resistance in which the surface appearance does not deteriorate due to repeated friction caused by cloth or paper in the cleaning operation, and has a design property such as a household appliance member or a housing equipment member. It is to provide a material used for an important member.
[0006]
[Means for Solving the Problems]
The present inventors have conducted intensive research to solve the above technical problems. As a result, in a composition composed of a propylene-based polymer and a polysiloxane, which has been conventionally considered to reduce the scratch resistance, a propylene polymer having a certain level of crystallinity and a polysiloxane having a specific weight average molecular weight On the contrary, it was found that the scratch resistance was drastically improved, and further, it was found that the stain resistance was improved as a secondary effect, and the present invention was achieved.
[0007]
That is, the present invention relates to 100 parts by weight of a propylene polymer having an isotactic pentat fraction of 0.97 or more in the boiling heptane insoluble part, and a polysiloxane having a weight average molecular weight (Mw) of 10,000 to 1,000,000. A propylene-based resin composition comprising 1 to 10 parts by weight.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
The propylene-based polymer used in the present invention is not particularly limited as long as it has the isotactic pentad defined in the present invention. For example, propylene homopolymer, α other than propylene and propylene -Copolymers with olefins can be used.
[0009]
In this case, the content of α-olefin other than propylene is preferably less than 6.0 mol% in monomer units.
[0010]
Examples of the α-olefin other than propylene include ethylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 4-methyl-1-pentene, and the like. 2 or more of them may be contained. Further, the propylene-α-olefin copolymer may be a random copolymer or a block copolymer, and among them, a block copolymer is preferable.
[0011]
Among the propylene polymers described above, propylene homopolymers are preferably used.
[0012]
The propylene-based polymer used in the present invention generally has a boiling heptane-insoluble content of 70% by weight or more, preferably 80% by weight or more, particularly 90% by weight or more, more preferably 95% in the case of a propylene homopolymer. It is suitable that it is at least wt%.
[0013]
Furthermore, in the present invention, it is essential that the isotactic pentad fraction by ¹³ C-NMR of the boiling heptane insoluble part used for the crystallinity index of the propylene-based polymer is 0.970 or more, particularly It is preferable that it is 0.975 or more because the surface hardness of the molded body can be effectively increased. When the isotactic pentad fraction is less than 0.970, the surface hardness of the molded product is low, and a predetermined scratch resistance cannot be obtained.
[0014]
Here, the isotactic pentad fraction of the boiling heptane-insoluble part is the A.I. According to the method published by Zambelli et al. (Macromolecules, 13 , 267 (1980)), the fraction of propylene monomer units at the center of a chain of five meso-bonded propylene monomer units in a pentad unit in a polypropylene molecule was determined. The measured value.
[0015]
In the present invention, the melt flow rate (hereinafter also abbreviated as MFR) of the propylene-based polymer is not particularly limited, but is 1 to 100 g / 10 min in consideration of moldability, rigidity, and impact resistance. Is preferable, it is more preferable that it is 10-70 g / 10min, and it is further more preferable that it is 10-30 g / 10min. The MFR in the present invention is a value at a temperature of 230 ° C. according to JIS K7210.
[0016]
In the present invention, the propylene-based polymer may be obtained by any method. Usually, a so-called Ziegler-Natta type stereospecific catalyst, which is a magnesium chloride-supported titanium compound or a catalyst comprising a titanium trichloride compound and an organoaluminum compound, is preferably used.
[0017]
As said titanium compound, the well-known compound used for superposition | polymerization of an olefin is employ | adopted without a restriction | limiting. In particular, a titanium compound having a high catalytic activity containing titanium, magnesium and halogen as components and a highly crystalline polymer can be obtained. Examples of such titanium compounds include those obtained by supporting titanium halides, particularly titanium tetrachloride, on various magnesium compounds.
[0018]
As a method for producing this catalyst, a known method is adopted without any limitation. For example, a method of co-grinding titanium tetrachloride with a magnesium compound such as magnesium chloride, a method of co-pulverizing titanium halide and a magnesium compound in the presence of an electron donor such as alcohol, ether, ester, ketone or aldehyde, or a solvent Among them, a method of bringing a titanium halide, a magnesium compound and an electron donor into contact with each other can be mentioned.
[0019]
As the organoaluminum compound, known compounds used for olefin polymerization can be used without any limitation. For example, alkylaluminums such as trimethylaluminum, triethylaluminum, and tri-n-propylaluminum; halogen atom-containing alkylaluminums such as ethylaluminum sesquichloride and diethylalumonium chloride can be used.
[0020]
Moreover, in order to improve the crystallinity of the polymer obtained, it is preferable to use an electron donor in addition to the titanium compound and the organoaluminum compound. Examples of the electron donor include ethers, amines, amides, sulfur-containing compounds, nitriles, carboxylic acids, acid amides, acid anhydrides, acid esters, and organosilicon compounds. Among these, an organosilicon compound is preferable.
[0021]
The polymerization method may be performed by polymerization in either a gas phase or a liquid phase. Also, it may be polymerized in an inert liquid or inert solvent for the catalyst, and the molecular weight adjusted by introducing hydrogen during the polymerization, or the obtained polymer may be adjusted with a molecular weight regulator such as an organic peroxide. It may be degraded. Furthermore, the polymerization can be carried out by any of batch, semi-batch and continuous methods.
[0022]
The polymerization conditions are not particularly limited as long as the effects of the present invention are not hindered, and known conditions can be adopted. For example, the polymerization temperature is preferably 20 to 200 ° C, and more preferably 50 to 150 ° C. Furthermore, the polymerization may be performed in two or more stages with different conditions.
The polysiloxane used in the present invention can be used without any limitation as long as the weight average molecular weight (Mw) is 10,000 to 1,000,000. When the weight average molecular weight is less than 10,000, a sticky feeling is generated on the surface of the molded product, and when it exceeds 1,000,000, the dispersibility in the propylene-based polymer is lowered, and the scratch resistance is not exhibited.
[0023]
It is essential that the content of the polysiloxane is 0.1 to 10 parts by weight with respect to 100 parts by weight of the propylene polymer, and more preferably 0.5 to 5.0 parts by weight. . If the amount is less than 0.1 parts by weight, the scratch resistance effect is not exhibited. If the amount exceeds 10 parts by weight, the surface hardness is lowered and the predetermined scratch resistance is not exhibited.
[0024]
Among the polysiloxanes used in the present invention, organosiloxane, fluorine-modified polysiloxane and the like are preferable, and specific examples include polydimethylsiloxane, polymethylphenylsiloxane, polydimethyl-diphenylsiloxane, and the like. It may be a mixture of
Moreover, it is preferable to mix | blend a crystal nucleating agent with the propylene-type resin composition of this invention for the abrasion-resistant improvement. A known crystal nucleating agent can be used without any limitation. Specifically, carboxylic acid metal salts such as aluminum benzoate, potassium benzoate, sodium benzoate, lithium benzoate, Al-p-butylbenzoate, sodium β-naphthoate, sodium cyclohexanecarboxylate, sodium cyclopentanecarboxylate Compounds: sodium bis (4-t-butylphenyl) phosphate, lithium bis (4-t-butylphenyl) phosphate, aluminum bis (4-t-butylphenyl) phosphate, bis (4-t -Butylphenyl) calcium phosphate, bis (4-t-butylphenyl) magnesium phosphate, 2,2'-methylene-bis (4,6-di-t-butylphenyl) phosphate sodium salt, 2,2 ' -Methylene-bis (4,6-di-tert-butylphenyl) phosphate lithium salt, 2,2'-methyle -Bis (4,6-di-t-butylphenyl) aluminum phosphate, 2,2'-methylidene-bis (4,6-di-t-butylphenyl) calcium phosphate, 2,2'-methylidene-bis (4,6-di-t-butylphenyl) magnesium phosphate, 2,2'-ethylidene-bis (4,6-di-t-butylphenyl) phosphate sodium salt, 2,2'-ethylidene-bis Lithium (4,6-di-t-butylphenyl) phosphate, 2,2'-ethylidene-bis (4,6-di-t-butylphenyl) aluminum phosphate, bis- (4-t-butyl) Aromatic metal phosphate compounds such as phenyl) calcium phosphate, bis- (4-t-butylphenyl) magnesium phosphate; dibenzylidene sorbitol, 1,3,2,4-di (methylbenzylidene) Rubitol, 1,3,2,4-di (ethylbenzylidene) sorbitol, 1,3,2,4-di (butylbenzylidene) sorbitol, 1,3,2,4-di (methoxybenzylidene) sorbitol, 1.3 , 2,4-di (ethoxybenzylidene) sorbitol, 1,3-chlorobenzylidene-2,4-methylbenzylidene sorbitol, dibenzylidene sorbitol compounds such as mono (methyl) dibenzylidene sorbitol; silica, titanium dioxide, carbon black, Inorganic compounds such as fine powder talc, mica, alum, and pigment can be used. Of these, in particular, using Al-pt-butylbenzoate, 2,2′-methylene-bis (4,6-di-tert-butylphenyl) phosphate metal salt, etc. improves the scratch resistance. Preferred above.
[0025]
In the present invention, the compounding amount of the crystal nucleating agent is preferably 0.05 to 5.0 parts by weight with respect to 100 parts by weight of the propylene polymer, and among these, 0.1 to 1.0 parts by weight is particularly preferable. preferable. Two or more of the above crystal nucleating agents may be used in combination.
[0026]
In addition to the said component, arbitrary compounding components can be mix | blended with the propylene-type resin composition of this invention according to various objectives in the range which does not inhibit the effect of this invention. Specifically, antioxidants, heat stabilizers, light stabilizers, ultraviolet absorbers, lubricants, antifogging agents, antiblocking agents, slip agents, crosslinking agents, flame retardants, dispersants, antistatic agents, colorants, Various additives such as inorganic fillers, antibacterial agents, and fragrances can be blended.
[0027]
【Example】
EXAMPLES Next, although an Example demonstrates this invention concretely, this invention is not limited to these Examples. In addition, the test and evaluation in an Example were performed by the method shown below.
(1) After isotactic pentad fraction propylene-based polymerization of boiling heptane part was completely dissolved in boiling xylene, the temperature was lowered to 20 ° C. and left to stand still, then separated and filtered, and the insoluble part was dried, The extraction residue obtained by performing boiling heptane extraction for 12 hours in a Soxhlet extraction tube was subjected to A.M. using JNM-GSX-270 ( ¹³ C-nuclear resonance frequency 67.8 MHz) manufactured by JEOL Ltd. According to the method published by Zambelli et al. (Macromolecules 6 925 1973), the fraction of propylene monomer units at the center of a chain in which five propylene monomer units in the polypropylene molecule were meso-bonded in succession was determined. The measurement conditions are as follows.
Measurement mode: ¹ H-complete decoupling pulse width: 7.0 microseconds (C45 degrees)
Pulse repetition time: 3 seconds Cumulative count: 10,000 times Solvent: Mixed solvent of orthodichlorobenzene / heavy benzene (90/10 vol%)
Sample concentration: 120 mg / 2.5 ml Solvent measurement temperature: 120 ° C.
(2) Scratch test-a
Using a 100-ton injection molding machine manufactured by Nippon Steel Works, a resin test piece of 90 mm × 60 mm × 2 tmm was produced at a cylinder temperature of 220 ° C. The test piece was fixed to a fully automatic crosscut peel tester manufactured by Yasuda Seiki Seisakusho, and a 100 g load was applied with the diamond needle (R = 250 μm) standing upright on the test piece surface, and the test piece was 10 mm / sec. Slide at speed.
After the test was completed, the difference between the highest point and the lowest point of the scar was measured with a laser microscope [1LM21] manufactured by Lasertec Co., Ltd. to obtain the maximum scratch depth (μm).
(3) Scratch test-b
Using a 100-ton injection molding machine manufactured by Nippon Steel Works, a resin test piece of 90 mm × 60 mm × 2 tmm was produced at a cylinder temperature of 220 ° C. This test piece is fixed to a fully automatic crosscut peel tester manufactured by Yasuda Seiki Seisakusho, toilet paper is attached to a 2 cm square metal pad and brought into contact with the test piece surface, and the test piece is 10 mm / sec at a pressure of 100 g / cm ^2. The test was performed by reciprocating 100 times. After completion of the test, the surface condition of the test piece was visually evaluated in the following four stages.
◎: When the scratch on the surface of the specimen is hardly noticeable ○: When the scratch on the surface of the specimen is somewhat conspicuous △: When the scratch on the surface of the specimen is conspicuous ×: When the scratch on the surface of the specimen is conspicuous (4) Resistance A mold with a mirror finish (# 6000) for contamination test was mounted on a 100 t injection molding machine manufactured by Nippon Steel Works, and a resin test piece of 90 mm × 60 mm × 2 mmt was produced at a cylinder temperature of 220 ° C. A contaminated liquid prepared according to JIS C9609 appendix 4 was applied to this test piece (mirror side) and dried at room temperature. Next, the test piece was fixed to a fully automatic cross-cut peel tester manufactured by Yasuda Seiki Seisakusho, and a cotton pad (20 mm × 20 mm) was crimped to the coated surface at 500 g / cm ² for 100 reciprocations at a speed of 10 mm / sec. It was. Thereafter, the ratio of the area where the contamination remained (remaining area / application area × 100) was measured using an image analyzer (Pierce).
[0028]
Example 1
100 parts by weight of a polypropylene homopolymer having a boiling heptane insoluble content of 98% by weight and an isotactic pentat fraction of the boiling heptane insoluble part of 0.975, and a polydimethylsiloxane having a weight average molecular weight (Mw) of 250,000. After 0 part by weight was melt kneaded at 230 ° C. with a single screw extruder (50 mmφ), a test piece was prepared according to the test method.
Thereafter, the scratch resistance (a), (b) and the stain resistance test were performed by the above test and evaluation method. The results are shown in Table 1.
[0029]
Example 2
The same test as in Example 1 was performed except that the content of polydimethylsiloxane was 3.0 parts by weight. The results are shown in Table 1.
[0030]
Example 3
The same test as in Example 1 was performed except that the content of polydimethylsiloxane was 5.0 parts by weight. The results are shown in Table 1.
[0032]
Example 5
The same test as in Example 1 was performed except that polydimethylsiloxane having a weight average molecular weight (Mw) of 380000 was used. The results are shown in Table 1.
[0033]
Example 6
A test was conducted in the same manner as in Example 1 except that 0.3 part by weight of Al-pt-butylbenzoate was added as a crystal nucleating agent to 100 parts by weight of the propylene homopolymer. The results are shown in Table 1.
[0034]
Comparative Example 1
The same test as in Example 1 was performed except that polydimethylsiloxane was not included. The results are shown in Table 1.
[0035]
Comparative Example 2
The same test as in Example 1 was performed except that the content of polydimethylsiloxane was 15% by weight. The results are shown in Table 1.
[0036]
Comparative Example 3
The same test as in Example 1 was performed except that a polypropylene homopolymer having an isotactic pentat fraction of 0.963 in the boiling heptane insoluble part was used. The results are shown in Table 1.
[0037]
Comparative Example 4
The same test as in Example 1 was performed except that polydimethylsiloxane having a weight average molecular weight (Mw) of 8000 was used. The results are shown in Table 1.
[0038]
Comparative Example 5
The same test as in Example 1 was performed except that polydimethylsiloxane having a weight average molecular weight (Mw) of 1200000 was used. The results are shown in Table 1.
[0039]
[Table 1]

Claims (2)

100 parts by weight of a propylene-based polymer having an isotactic fraction of the boiling heptane insoluble part of 0.97 or more, and 0.1 to 10 parts by weight of a polysiloxane having a weight average molecular weight (Mw) of 250,000 to 1000000 comprising the resin composition of the propylene resin composition characterized by being obtained by melt-kneading. The propylene-based resin composition according to claim 1 , wherein the polysiloxane is polydimethylsiloxane.