JP3737225B2 - Propylene-based polymer composition and blow molded article comprising the composition - Google Patents

Description

【００５７】
【表２】

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a propylene polymer composition, a propylene polymer composition for blow molding, and a blow molded article obtained by blow molding the composition.
[0002]
TECHNICAL BACKGROUND OF THE INVENTION
Propylene polymers such as propylene homopolymers and propylene copolymers have good properties such as mechanical properties, heat resistance and chemical resistance, so hollow molded products such as blow molded products, films, sheets, etc. And is used for various purposes. However, depending on the application, impact resistance may not be sufficient. As a method for improving the impact resistance of a molded product made of a propylene-based polymer, for example, a propylene-based polymer is blended with a modifier such as a low crystalline ethylene / α-olefin copolymer to obtain a composition. The method is known.
[0003]
For example, JP-A-1-247445 discloses a component (A) comprising a crystalline propylene polymer or copolymer containing 1 to 100000 wtppm of a 3-position branched α-olefin having 6 or more carbon atoms or vinylcycloalkane. 95 to 40 wt%, a density of 0.950 to 0.890 g / cc, and a refractive index of an ethylene polymer or copolymer component (B) of 3 to 55 wt% that is higher than the component (A) And a composition characterized by comprising 2 to 40 wt% of an ethylene copolymer component (C) having a density of 0.890 g / cc or less and a refractive index of component (A) or less. In the examples, a composition comprising a crystalline polypropylene copolymer, a branched low-density polyethylene, and an ethylene-butene-1 rubber-like polymer is described. However, such a composition may not have sufficient impact resistance depending on the application, and when formed into a bottle by blow molding, the surface hardness and drop strength may not be sufficient.
[0004]
JP-A-3-59049 discloses (a) 40 to 80% by weight of polypropylene having a melt flow index of 0.7 g / 10 min or less and (b) a melt flow index of 0.2 g / 10 min or less. 5 to 35% by weight of polyethylene, and (c) an ethylene-α-olefin copolymer rubber having a melt flow index of 1.0 g / 10 min or less and more than 15% by weight and 25% by weight or less, 0.3 g / 10 A polyolefin composition characterized by having a melt flow index of less than or equal to a minute is described, and in the examples, a composition comprising a crystalline polypropylene copolymer, high-density polyethylene, and ethylene / propylene copolymer rubber Is described. However, when such a composition is molded into a bottle, the surface hardness may not be sufficient, and the appearance of the weld may not be good.
[0005]
As a result of intensive studies in view of such conventional techniques, the present inventors have found that this is a copolymer of a propylene polymer, ethylene and an α-olefin having 6 to 20 carbon atoms, and the density is 0. An ethylene / α-olefin copolymer in the range of 905 to 0.95 g / cm ³ , and a copolymer of ethylene and an α-olefin having 4 to 20 carbon atoms, and the density is 0.85 g. / cm ³ or more 0.87 g / cm consisting of ethylene · alpha-olefin copolymer in less than ³ ranges composition is excellent in balance between rigidity and impact resistance, transparency, surface smoothness (gloss) In addition, the present inventors have found that a blow molded article having excellent surface hardness, good weld appearance, and excellent drop strength can be obtained.
[0006]
OBJECT OF THE INVENTION
The present invention has been made in view of the prior art as described above, and is excellent in balance between rigidity and impact resistance, excellent in transparency, surface smoothness (gloss) and surface hardness, and in the weld portion. For the purpose of providing a propylene polymer composition, a propylene polymer composition for blow molding, and a blow molded article comprising this composition, which can provide a blow molded article having good appearance and excellent drop strength. Yes.
[0007]
SUMMARY OF THE INVENTION
The propylene-based polymer composition according to the present invention is
(A) The content rate of 64 degreeC decane soluble components exists in the range of 0.1-20 weight%, The melt flow rate measured by 230 degreeC and a 2.16kg load is the range of 0.05-50 g / 10min. Propylene polymer in: 30 to 93% by weight;
(B) A copolymer of ethylene and an α-olefin having 6 to 20 carbon atoms and having a density in the range of 0.905 to 0.95 g / cm ^3. : 5 to 35% by weight;
(C) A copolymer of ethylene and an α-olefin having 4 to 20 carbon atoms, and having a density in the range of 0.85 g / cm ³ or more and less than 0.87 g / cm ³ olefin copolymer: from 2 to 35 consists of a weight%
(B) Density of ethylene / α-olefin copolymer (d _B ) And the density of the (C) ethylene / α-olefin copolymer (d _C ) (D _B -D _C ) Is in the range of 0.04 to 0.085 .
[0009]
In the (B) ethylene / α-olefin copolymer, the α-olefin having 6 to 20 carbon atoms is preferably a linear α-olefin.
The propylene-based polymer composition for blow molding according to the present invention is characterized by comprising the propylene-based polymer composition.
[0010]
The blow molded article according to the present invention is obtained by blow molding the propylene polymer composition.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the propylene-based polymer composition, the propylene-based polymer composition for blow molding, and the blow-molded body comprising the composition will be specifically described.
[0012]
The propylene-based polymer composition according to the present invention comprises (A) a propylene-based polymer, (B) an ethylene / α-olefin copolymer and (C) an ethylene / α-olefin copolymer having different densities. It is configured.
[0013]
First, each component constituting the propylene polymer composition according to the present invention will be described.
(A) Propylene polymer The propylene polymer (A) is a homopolymer of propylene or a copolymer of propylene and ethylene or an α-olefin having 4 to 20 carbon atoms. . Examples of the α-olefin having 4 to 20 carbon atoms include ethylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1- Examples include tetradecene, 1-hexadecene, 1-octadecene, and 1-eicocene. These α-olefins can be used alone or in combination of two or more. These α-olefins may form a random copolymer with propylene or may form a block copolymer. In the present invention, a propylene homopolymer, a crystalline propylene / ethylene block copolymer having an ethylene content of 2 to 40 mol%, and a crystalline propylene / ethylene random copolymer having an ethylene content of 0.5 to 10 mol% are preferred. .
[0014]
In such a propylene polymer (A), the content of the 64 ° C. decane-soluble component is 0.1 to 20% by weight, preferably 0.1 to 15% by weight, more preferably 0.1 to 10% by weight. %, And the intrinsic viscosity [η] in 135 ° C. decalin of a 64 ° C. decane-soluble component is usually 0.1 to 6 dl / g, preferably 0.1 to 4 dl / g, more preferably 0.5. It is in the range of ˜4 dl / g. This 64 ° C. decane-soluble component is usually a rubber component and an atactic component.
[0015]
The pentad isotacticity (mmmm fraction) of the 64 ° C. decane insoluble component is usually in the range of 0.95 to 0.99, preferably 0.97 to 0.99.
[0016]
The melt flow rate of the propylene polymer (A) measured at 230 ° C. and 2.16 kg load is usually 0.05 to 50 g / 10 minutes, preferably 0.05 to 40 g / 10 minutes, preferably 0.05. It is in the range of ˜30 g / 10 minutes.
[0017]
The density is usually in the range of 0.885 to 0.91 g / cm ³ , preferably 0.89 to 0.91 g / cm ³ , more preferably 0.895 to 0.91 g / cm ³ , and the refractive index. Is usually in the range of 1.490 to 1.510, preferably 1.495 to 1.510, more preferably 1.500 to 1.510.
[0018]
In the present invention, the amount of the 64 ° C. decane-soluble component of the propylene-based polymer composition is measured as follows. That is, 2 g of a sample and 0.05 g of a stabilizer are added to 500 ml of decane and stirred at 145 ° C. until it melts. When melted, the melting temperature is adjusted to 64 ° C., and after slowly stirring at 64 ° C. for 2 hours, the decane soluble component and the insoluble component (precipitated component) are filtered by filtration through a filter heated to 64 ° C. To separate. The decane-soluble component is poured into 3 liters of acetone and precipitated by stirring for 24 hours. This precipitated component is filtered, dried at room temperature under reduced pressure for 24 hours, and then weighed to measure the amount of the decane-soluble component.
[0019]
Moreover, the content rate of a 64 degreeC decane insoluble component is measured as follows. That is, the decane-insoluble component (deposited component) obtained in the measurement of the amount of the decane-soluble component was added again to 500 ml of decane and melted at 145 ° C., and this solution was poured into 3 liters of acetone. Precipitate by stirring for 24 hours. The precipitated component is filtered, dried at room temperature under reduced pressure for 24 hours, and then weighed to measure the amount of decane insoluble component.
[0020]
In the present invention, the mmmm fraction, MFR, density and refractive index are measured as follows.
The mmmm fraction is P _mmmm in ¹³ C-NMR spectrum (absorption intensity derived from the methyl group of the third unit in a site where 5 units of propylene units are continuously isotactic bonded) and P _W (total methyl groups of propylene units). (Absorption intensity derived from the above) is determined by the following formula.
[0021]
mmmm fraction = P _mmmm / P _W
The NMR measurement is performed as follows, for example. That is, 0.35 g of a sample is dissolved by heating in 2.0 ml of hexachlorobutadiene. After this solution is filtered through a glass filter (G2), 0.5 ml of deuterated benzene is added and charged into an NMR tube having an inner diameter of 10 mm. And ¹³ C-NMR measurement is performed at 120 degreeC using the JEOL Co., Ltd. product GX-500 type | mold NMR measuring apparatus. The number of integration is 10,000 times or more.
[0022]
MFR is measured under the conditions of 230 ° C. and 2.16 kg load in accordance with ASTM D1238.
The density is measured by JIS K7112 A method.
[0023]
The refractive index is measured with a sodium wire (λ ₀ = 589.3 nm) using an Abbe refractometer 2T type (manufactured by Atago Co., Ltd.).
The propylene polymer (A) having such characteristics can be produced by various methods. For example, a catalyst formed from a solid titanium catalyst component and an organometallic compound catalyst component, or both of these components And a highly active titanium catalyst formed from an electron donor, a catalyst formed from a metallocene compound and an aluminoxane, or a catalyst obtained by mixing these catalysts. Further, when the propylene-based polymer (A) is a block copolymer, it can be produced using a different catalyst selected from the above catalysts for each stage during multistage polymerization.
[0024]
(B) Ethylene / α-olefin copolymer (B) The ethylene / α-olefin copolymer is a copolymer of ethylene and an α-olefin having 6 to 20 carbon atoms. Examples of the α-olefin having 6 to 20 carbon atoms include 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene and combinations thereof. Of these, 4-methyl-1-pentene and 1-hexene are preferable, and 1-hexene is particularly preferable.
[0025]
In such (B) ethylene / α-olefin copolymer, the density is 0.905 to 0.95 g / cm ³ , preferably 0.910 to 940 g / cm ³ , more preferably 0.920 to 0.00. It is in the range of 940 g / cm ³ .
[0026]
The melt flow rate measured at 190 ° C. and a load of 2.16 kg is usually in the range of 0.001 to 15 g / 10 min, preferably 0.005 to 15 g / 10 min, preferably 0.01 to 10 g / 10 min. The refractive index is usually in the range of 1.50050 to 1.5400, preferably 1.5070 to 1.5400, more preferably 1.5090 to 1.5350.
[0027]
The melt flow rate of the ethylene / α-olefin copolymer is measured at 190 ° C. under a load of 2.16 kg in accordance with ASTM D1238-65T.
The ethylene / α-olefin copolymer (B) having such characteristics can be produced by various methods. For example, a catalyst formed from a solid titanium catalyst component and an organometallic compound catalyst component, Or it can manufacture using the highly active titanium catalyst formed from these both components and an electron donor, the catalyst formed from a metallocene compound and an aluminoxane, or the catalyst which mixed these catalysts.
[0028]
(C) Ethylene / α-olefin copolymer (C) The ethylene / α-olefin copolymer is a copolymer of ethylene and an α-olefin having 4 to 20 carbon atoms. Examples of the α-olefin having 4 to 20 carbon atoms include 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, Examples include 1-hexadecene, 1-octadecene, 1-eicocene, and combinations thereof. Of these, 1-butene is preferred.
[0029]
In such (C) an ethylene · alpha-olefin copolymer, density, 0.85 g / cm ³ or more 0.87 g / cm less than ^3, preferably 0.855 g / cm ³ or more 0.87 g / cm less than ³ More preferably, it is in the range of 0.86 g / cm ³ or more and less than 0.87 g / cm ³ .
[0030]
The melt flow rate measured at 190 ° C. and a load of 2.16 kg is usually in the range of 0.001 to 15 g / 10 min, preferably 0.005 to 15 g / 10 min, preferably 0.01 to 10 g / 10 min. The refractive index is usually in the range of 1.4700 to 1.4950, preferably 1.4720 to 1.4950, more preferably 1.4750 to 1.4950.
[0031]
The ethylene / α-olefin copolymer (C) having such characteristics can be produced by various methods. For example, a catalyst formed from a solid titanium catalyst component and an organometallic compound catalyst component, Or it can manufacture using the highly active titanium catalyst formed from these both components and an electron donor, the catalyst formed from a metallocene compound and an aluminoxane, or the catalyst which mixed these catalysts.
[0032]
Propylene polymer composition The propylene polymer composition according to the present invention comprises:
(A) Propylene polymer: 30 to 93% by weight, preferably 40 to 90% by weight, more preferably 50 to 85% by weight;
(B) ethylene / α-olefin copolymer: 5 to 35% by weight, preferably 10 to 35% by weight, more preferably 10 to 30% by weight;
(C) Ethylene / α-olefin copolymer: 2 to 35% by weight, preferably 5 to 35% by weight, more preferably 5 to 30% by weight.
[0033]
In the present invention, the (B) Density of the ethylene · alpha-olefin copolymer (d _B), wherein (C) the difference between the density of the ethylene · alpha-olefin copolymer (d _C) (d _B -d (B) an ethylene / α-olefin copolymer and (C) an ethylene / α-olefin copolymer so that _C ) is in the range of 0.04 to 0.085, preferably 0.05 to 0.08. Are preferably combined.
[0034]
And (B) a density of the ethylene · alpha-olefin copolymer (d _B), when the difference between the (C) The density of the ethylene · alpha-olefin copolymer (d _C) is within the above range The resulting composition has an excellent balance between rigidity and impact resistance.
[0035]
The density of the composition comprising (B) the ethylene / α-olefin copolymer and (C) the ethylene / α-olefin copolymer is substantially the same as the density of the (A) propylene-based polymer. It is preferable to combine the components. Thus, when each component is combined, the obtained composition is excellent in transparency.
[0036]
The propylene-based polymer composition includes a weather resistance stabilizer, a heat resistance stabilizer, an antistatic agent, an anti-slip agent, an anti-blocking agent, an antifogging agent, a lubricant, a pigment, a dye, as long as the object of the present invention is not impaired. Additives such as a nucleating agent, a plasticizer, an anti-aging agent, a hydrochloric acid absorbent, and an antioxidant may be blended as necessary.
[0037]
For the propylene polymer composition, a propylene polymer (A), an ethylene / α-olefin copolymer (B), and an ethylene / α-olefin copolymer (C) are selected so as to satisfy the characteristics as described above. And it can manufacture by blending by a well-known method.
[0038]
Specifically as a method of blending each component,
(1) Propylene-based polymer (A), ethylene / α-olefin copolymer (B), ethylene / α-olefin copolymer (C) and optionally other components blended using an extruder, kneader, etc. how to,
(2) A propylene-based polymer (A), an ethylene / α-olefin copolymer (B), an ethylene / α-olefin copolymer (C) and optionally other components are mixed with an appropriate good solvent (for example, hexane, A hydrocarbon solvent such as heptane, decane, cyclohexane, benzene, toluene, xylene), and then removing the solvent,
(3) Propylene-based polymer (A), ethylene / α-olefin copolymer (B), ethylene / α-olefin copolymer (C) and other components as required are dissolved separately in an appropriate good solvent. Preparing a prepared solution, mixing and then removing the solvent,
(4) The method of combining the methods (1) to (3) above and the like can be mentioned.
[0039]
The propylene-based polymer composition according to the present invention can be molded by various molding methods such as blow molding, vacuum / pressure molding, calender molding, inflation molding, extrusion molding, foam molding, stretched film molding, injection molding, and the like. It can be used for various purposes. The propylene polymer composition according to the present invention is particularly suitable as a material for blow molding.
[0040]
Blow molded article A blow molded article comprising the propylene polymer composition according to the present invention is obtained by blow molding the propylene polymer composition obtained as described above. The blow molded body can be manufactured by a conventionally known blow molding apparatus. Also, conventionally known conditions can be adopted as the molding conditions. For example, in the case of extrusion blow molding, a tube-shaped parison is extruded from a die at a resin temperature of 100 to 300 ° C. in a molten state, and then the parison is held in a mold having a shape to be applied. Then, air is blown into the mold at a resin temperature of 130 to 300 ° C. to obtain a hollow molded product. The draw ratio is desirably 1.5 to 5 times in the transverse direction.
[0041]
In the case of injection blow molding, the propylene-based polymer composition is injected into a mold at a resin temperature of 100 ° C. to 300 ° C. to form a parison, and then the parison is held in a mold having a shape to be applied. Air is blown into the mold at a resin temperature of 120 ° C. to 300 ° C. to obtain a hollow molded body. The draw ratio is desirably 1.1 to 1.8 times in the longitudinal direction, and desirably 1.3 to 2.5 times in the transverse direction.
[0042]
Examples of the blow molded article thus obtained include cosmetic bottles, detergent bottles, bath detergent detergents such as shampoos, rinses and body soaps, industrial chemical cans, drum cans and bottles.
[0043]
【The invention's effect】
The propylene-based polymer composition according to the present invention has an excellent balance between rigidity and impact resistance, excellent transparency, surface smoothness (gross) and surface hardness, a good weld appearance, and good drop strength. An excellent blow molded article can be obtained.
[0044]
The blow molded product according to the present invention is excellent in balance between rigidity and impact resistance, excellent in transparency, surface smoothness (gross) and surface hardness, and has a good appearance in the weld part and excellent in drop strength. .
[0045]
【Example】
EXAMPLES Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples.
[0046]
In the examples, MFR, density and refractive index were measured by the methods described above. The flexural modulus, impact strength, and haze were measured as follows using a sample obtained by press-molding a propylene-based polymer composition at 230 ° C.
[0047]
Flexural modulus (FM)
In accordance with ASTM D 790, a test piece having a thickness of 2 mm was used, and measurement was performed under conditions of a span interval of 32 mm and a bending speed of 5 mm / min.
[0048]
Impact strength (IZ)
Based on ASTM D256, it measured at 0 degreeC using the test piece (rear notch) of thickness 3mm.
[0049]
Haze
Using a test piece having a thickness of 0.5 mm, measurement was performed with a digital turbidimeter NDH-20D manufactured by Nippon Denshoku Industries Co., Ltd.
[0050]
The drop strength, appearance, and surface hardness were determined using a 200 ml bottle with a propylene-based polymer composition pellet produced by kneading and blow molded at 230 ° C. with a mold water cooling in a blow molding machine. Each test was performed and visually evaluated as follows. The gloss was measured using the bottle as follows.
[0051]
Drop strength 100 ml of water was put into a bottle, and the container was dropped from a height of 1.8 m in an atmosphere of 0 ° C, and the number of bottles whitened or broken was evaluated.
[0052]
Appearance Weld thickness unevenness was visually observed and evaluated according to the following criteria.
◎: No thickness unevenness ○: Little thickness unevenness Δ: Thickness unevenness is slightly noticeable ×: Thickness unevenness is quite noticeable
Surface hardness A nail was pressed against the surface of a test piece having a thickness of 2 mm, and evaluation was made according to the following criteria based on the degree of scratching.
[0053]
○: Scratches are scarcely △: Scratches are slightly noticeable ×: Scratches are quite noticeable
Gross The side of the bottle was measured using a gonio-gloss meter VG-1D type (manufactured by Nippon Denshoku Co., Ltd.), the amount of specular reflection was measured at an incident angle of 60 degrees, and the percentage of specular gloss ( %).
[0054]
Examples 1 to 4
A propylene-based polymer (A) as shown in Table 1, an ethylene / α-olefin copolymer (B), and an ethylene / α-olefin copolymer (C) at 230 ° C. in the proportions shown in Table 2. A propylene-based polymer composition obtained by melt kneading was prepared, and various physical properties were measured. The results are shown in Table 2.
[0055]
[Comparative Examples 1-4]
As component (B), (b'-1) ethylene / propylene copolymer, (b'-2) ethylene / butene copolymer, (b'-3) ethylene homopolymer shown in Table 1 are used as component (C). ) Using (c'-1) ethylene / butene copolymer and (c'-2) ethylene / propylene copolymer shown in Table 1 in the proportions shown in Table 2, and propylene in the same manner as in Examples 1 to 4. A system polymer composition was prepared and various physical properties were measured. The results are shown in Table 2.
[0056]
[Table 1]

[0057]
[Table 2]

Claims (4)

(A) The content rate of 64 degreeC decane soluble components exists in the range of 0.1-20 weight%, The melt flow rate measured by 230 degreeC and a 2.16kg load is the range of 0.05-50 g / 10min. Propylene polymer in: 30 to 93% by weight;
(B) A copolymer of ethylene and an α-olefin having 6 to 20 carbon atoms, and an ethylene / α-olefin copolymer having a density in the range of 0.905 to 0.95 g / cm ^3. : 5 to 35% by weight;
(C) an ethylene / α-copolymer of ethylene and an α-olefin having 4 to 20 carbon atoms and having a density in the range of 0.85 g / cm ³ or more and less than 0.87 g / cm ³ olefin copolymer: 2-35 wt% and made from the (B) and the density of the ethylene · alpha-olefin copolymer (d _B), wherein (C) the density of the ethylene · alpha-olefin copolymer (d _C And a difference (d _B -d _C ) in the range of 0.04 to 0.085. The propylene-based polymer composition according to claim 1 , wherein in the (B) ethylene / α-olefin copolymer, the α-olefin having 6 to 20 carbon atoms is a linear α-olefin. Claim 1 or 2 propylene-based polymer composition that blow molding the propylene polymer composition characterized consisting described. A blow-molded product obtained by blow-molding the propylene-based polymer composition according to claim 1 .