JPH07173335A - Polyolefin particle composition - Google Patents

Abstract

PURPOSE:To obtain a composition not causing clogging in a hopper or piping, excellent in fluidity and transparency even under a high temperature, and useful as a film or sheet by blending polyolefin particles with specific organic powder in a specific amount. CONSTITUTION:This composition consists of (A) 100 pts.wt. of polyolefin particles (preferably an ethylene-propylene random copolymer or an ethylene- propylene block copolymer having 100-800mum average particle diameter) having >=30wt.% of a content which is soluble in p-xylene at a room temperature and (B) 0.01-3.0 pts.wt. of at least one kind of organic substance powder, having 50mum average particle diameter and selected from (i) an OH group-containing fatty acid salt of a polyvalent metal (preferably a basic stearic acid aluminum salt or a basic stearic acid calcium salt), (ii) a polyolefin (e.g. a homopolymer of a monomer such as ethylene or propylene) having <=10wt.% of a content soluble in p-xylene at a room temperature and (iii) a silicone resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyolefin particle composition which does not cause clogging in a hopper or clogging of a pipe when powder is transferred. For more details,
The present invention relates to a polyolefin particle composition which exhibits excellent fluidity even when the particles have a relatively high temperature and does not impair the transparency when formed into a molded product.

[0002]

2. Description of the Related Art Conventionally, polyolefin having rubber elasticity has been used for various purposes similar to rubber. However, since the polyolefin having rubber elasticity has a large amount of an amorphous polymer portion, the polymer itself has an adhesive property, and thus it is rarely obtained in the form of particles by polymerization, and it is obtained in the form of particles. However, due to the tackiness of the particles, it was difficult to obtain particles having a smooth feeling because the particles stick to each other and have a smooth feel.

When the fluidity of the polyolefin particles is insufficient, problems such as hanging in the hopper occur, and when powder transfer is performed, the polyolefin particles become clogged in the piping, making it difficult to handle. There was a problem.

On the other hand, various methods for solving these problems have been proposed. Japanese Unexamined Patent Publication (Kokai) No. 5-70601 proposes a method of improving the fluidity of an elastomer powder by adding a fine inorganic or polyvinyl chloride powder having an average particle size of 30 μm or less to a thermoplastic elastomer powder. . However, as a result of the additional test conducted by the present inventors, although the fluidity of the elastomer powder is improved by these fine powders, when the inorganic fine powder is used, the transparency in the case of a molded product is improved. However, it has a drawback of being significantly lowered, and when a vinyl chloride resin is used, the processing temperature of polyolefin is 200 to 300 ° C.
However, there is a problem that hydrochloric acid is generated, which causes deterioration of the polyolefin and corrosion of the molding machine.

On the other hand, it is also known that the bulk density is improved by adding various metal soaps to the polyolefin powder. For example, in Japanese Patent Laid-Open No. 57-25344,
A method has been proposed in which the bulk density of the polyolefin powder is improved by adding metal soap having an average particle size of 0.01 to 50 μm to the polypropylene powder to improve storage or transportation. However, among the metal soaps disclosed herein, calcium stearate or the like forms a neutral salt of metal atoms in the metal soap and chlorine in the catalyst when the polyolefin particles are not subjected to the catalyst removal. As a result, the fatty acids are liberated, which causes problems such as roll stains during processing and bleed-out when formed into a film sheet.

[0006]

As described above, the flowability of a polyolefin powder containing a large amount of p-xylene-soluble components is improved, and even when this olefin powder is subjected to molding and processing, it is difficult to process. , And a fluidity improver that does not adversely affect the product quality has been desired.

[0007]

Means for Solving the Problems As a result of intensive research conducted by the inventors for the purpose of solving the above problems,
By adding a specific amount of a specific organic powder to the polyolefin particles, it has been found that it is possible to obtain polyolefin particles having good particle properties and not adversely affecting processing and product quality, thus completing the present invention. Came to.

That is, according to the present invention, (1) 100 parts by weight of polyolefin particles having a room temperature p-xylene soluble content of 30% by weight or more (2) OH group-containing fatty acid salt of polyvalent metal, room temperature p-xylene soluble content Is a polyolefin particle composition comprising 0.01 to 3.0 parts by weight of an organic powder having an average particle size of 50 μm or less and at least one selected from the group consisting of 10% by weight or less of a polyolefin and a silicone resin.

The polyolefin particles used in the present invention may be either α-olefin homopolymers or copolymers as long as the polyolefin particles have a room temperature p-xylene soluble content of 30% by weight or more. Polyolefin particles having a room temperature p-xylene soluble content of 30% by weight or more,
Since the amorphous polymer portion is included in a large amount, the particles are likely to stick to each other. In particular, it has the property of becoming extremely sticky when the temperature of the particles is 50 to 70 ° C. When such polyolefin particles are used, the effect of improving the fluidity of the present invention is satisfactorily exhibited. In particular, when the polyolefin particles having a p-xylene soluble content at room temperature of 50% by weight or more are used, the fluidity improving effect of the present invention is remarkable.

The polyolefin particles of the present invention may be removed from the polymerization system and may or may not be subjected to catalyst removal.

Specific examples of the polyolefin particles preferably used in the present invention include ethylene-based particles.
Propylene random copolymer, ethylene-propylene block copolymer, ethylene-butene random copolymer,
Ethylene-butene block copolymer, propylene-butene random copolymer, propylene-butene block copolymer, ethylene-propylene-butene random copolymer, ethylene-propylene-butene block copolymer,
Α such as ethylene-propylene-diene random copolymer
There may be mentioned copolymers of two or more olefins.

The average particle size of the polyolefin particles in the present invention is from 100 to 100 in order to exhibit good fluidity.
It is preferably in the range of 800 μm. Further, polyolefin particles in which the proportion of particles having a particle size of less than 100 μm and particles having a particle diameter of more than 1200 μm are 1% by weight or less can be preferably used.

Next, the organic powder used in the present invention will be described. The organic powder is at least one organic powder selected from the group consisting of polyvalent metal OH group-containing fatty acid salts, room temperature p-xylene solubles of 10% by weight or less, and silicone resins.

The OH group-containing fatty acid salt of a polyvalent metal used in the present invention may be a known compound, but is preferably a saturated or unsaturated C10-30, preferably 16-24, carbon atom. It is a thing. Further, the polyvalent metal is Mg, C
Suitable are a, Al, Zn, Sn and the like. Furthermore, this fatty acid salt must have at least one basic OH group. As a result, the release of fatty acids as a result of the reaction with chlorine contained in the catalyst in the polyolefin is less likely to occur, bleeding out in the case of a molded product is prevented, and transparency is not impaired. As a specific example of such a fatty acid salt, basic aluminum stearate, basic calcium stearate, monobasic or dibasic aluminum mistyrate, etc. are suitable.

The polyolefin having a room temperature p-xylene soluble content of 10% by weight or less used in the present invention is ethylene,
Propylene, 1-butene, 3-methyl-1-butene, 4
-Homopolymers selected from monomers such as methyl-1-pentene, 1-hexene, 1-octene, 1-decene and vinylcyclohexane, and random copolymers and blocks consisting of one or more monomers. A copolymer can be mentioned. Such a polyolefin has a room temperature p-xylene soluble content of 10 wt% or less, preferably 5 wt%.
It is the following. When the room temperature p-xylene soluble content is 10 wt% or more, the effect of improving the fluidity of the polyolefin particles of the present invention is not exhibited, which is not preferable. As such a polyolefin, those polymerized by various catalysts can be used, and for example, various Ti components, organoaluminum components,
And a catalyst system comprising an electron donor which is optionally used, or a polymer which is polymerized with a soluble or silica-supported zirconium or hafnium complex component, a catalyst system comprising a methylalumoxane component can be used without any limitation. . Alternatively, the polymer obtained by these catalyst systems may be obtained by pulverizing or sieving into a range of the average particle diameter of the present invention. In the present invention, a polymer containing propylene as a main component is most preferable.

The silicone resin used in the present invention may be a polymer having a silicon atom and having a siloxane bond as a skeleton, and any preparation method may be used. Particularly spherical, with a true specific gravity of 1.0 to 1.5 g / cc,
Those having a bulk specific gravity of 0.1 to 0.4 g / cc are preferably used.

The average particle size of the organic powder used in the present invention is 50 μm or less. If the average particle size is 50 μm or more, the effect of improving the particle fluidity cannot be achieved. The preferred range is
It is 0.5 to 40 μm.

In the present invention, the blending amount of the above-mentioned polyolefin particles and the organic powder is 100% by weight of the polyolefin particles.
The organic powder is 0.01 to 3.0 parts by weight with respect to parts by weight. A preferred range is 0.05 to 1.0 part by weight.
When the amount of the organic powder is less than 0.01 parts by weight, the fluidity of the polyolefin particles is poorly improved, and when it exceeds 3.0 parts by weight, the polyolefin particles are formed into a molded article by the organic powder blended with the polyolefin particles. When it becomes, the quality is changed, and undesired physical properties may be expressed, which is not preferable.

[0019]

EFFECTS OF THE INVENTION According to the present invention, there is no clogging in the hopper or clogging of the pipes when pneumatic transportation is performed, and when the film or sheet is processed, roll stains and transparency of the product are prevented. It is possible to obtain a polyolefin particle composition that does not have a negative effect such as reduction or bleedout.

[0020]

EXAMPLES In order to explain the present invention in more detail below,
Although examples and comparative examples are given, the present invention is not limited to these examples.

(1) Measuring method of falling seconds at 70 ° C. An outlet having a diameter of 10 mm is provided at the center of the lower portion, and the shape is such that the height is 175 mm, the inner diameter of the upper cylindrical portion is 68 mm, and the height of the cylindrical portion is 60 mm. 100 ml of powder preliminarily kept at 70 ° C. was put in a metal funnel, the powder was discharged while applying a vibration of 2 mm width in the lateral direction, and the time required for discharging the whole amount was measured.

(2) Method for measuring p-xylene soluble matter at room temperature About 1 g of polyolefin particles is weighed (weight A), added to 100 ml of p-xylene, heated to 130 ° C. with stirring, and further 30 Stirring was continued for a minute to prepare a uniform p-xylene solution. Then, after cooling to room temperature (23 ° C),
It was left for 24 hours. The precipitated gel-like substance was separated by filtration, and p-xylene was completely volatilized to obtain the weight of the soluble component (weight B), which was calculated as follows.

Room-temperature p-xylene solubles (wt%) = B / A × 100 (3) Evaluation of sheet forming and transparency A sheet having a thickness of 200 μm was formed by a 30 mmφ sheet forming machine. The sheet was in conformity with JIS K6714. The haze was measured immediately after molding and after standing at room temperature for 1 week.

(4) JIS A hardness According to JIS K6301.

Examples 1 to 9 The method for preparing the polyolefin particles used in the present invention is shown below.

(Preliminary Polymerization) A glass autoclave reactor having an internal volume of 1 liter equipped with a stirrer was sufficiently replaced with nitrogen gas, and then 400 ml of heptane was inserted. After keeping the temperature inside the reactor at 20 ° C. and adding 14.5 mmol of diethylaluminum chloride and 18.1 mmol of titanium trichloride (“TOS-17” manufactured by Marubeni Solvay Chemical Co., Ltd.), propylene becomes 3 g per 1 g of catalyst. Was continuously introduced into the reactor for 1 hour. The temperature during this period was kept at 20 ° C. After stopping the supply of propylene, the inside of the reactor was sufficiently replaced with nitrogen gas, and the obtained titanium-containing polypropylene was washed with purified heptane four times. As a result of analysis, catalyst 1
2.9 g of propylene had been polymerized per g.

(Main Polymerization) Step 1: Polymerization of 1-butene A glass autoclave reactor having an internal volume of 1 liter equipped with a stirrer was sufficiently replaced with nitrogen gas, and then heptane 4 was added.
00 ml was inserted. After keeping the temperature inside the reactor at 10 ° C., 0.70 mmol of diethylaluminum chloride and 0.087 mmol of titanium-containing polypropylene obtained by prepolymerization as titanium trichloride were added, and 1-butene was added to 10 g per catalyst. It was continuously introduced into the reactor for 2 hours.
The temperature during this period was kept at 10 ° C. After the supply of 1-butene was stopped, the inside of the reactor was replaced with nitrogen gas to obtain a titanium-containing poly-1-butene polymer. The obtained poly 1-butene was washed twice with purified heptane under a nitrogen atmosphere.
As a result of the analysis, 9.5 g of 1-butene was polymerized per 1 g of the titanium compound.

Step 2: Polymerization of Propylene and Copolymerization of Propylene-Ethylene 1 liter of propylene and 0.70 mmol of diethylaluminum chloride were added to a 2 liter autoclave subjected to nitrogen substitution, and the internal temperature of the autoclave was 70 ° C.
The temperature was raised to. 0.087 mmol of titanium-containing poly-1-butene was added as titanium trichloride, and propylene was polymerized at 70 ° C. for 30 minutes. Then, the inner temperature of the autoclave is rapidly lowered to 55 ° C., and at the same time, 0.35 mmol of ethylaluminum sesquiethoxide is added, and then ethylene is supplied so that the ethylene gas concentration becomes 10 mol%.
Copolymerization of propylene and ethylene was carried out at 5 ° C. for 90 minutes. During this period, the ethylene gas concentration was maintained at 10 mol% while confirming with a gas chromatograph. After the polymerization was completed, unreacted monomers were purged to obtain a white granular polymer.

No adhesion was observed in the polymerization tank or on the stirring blade. The yield was 110 g, and the polymerization ratio of all polymers was 5730 g-polymer / g-cat.

Separately, as a result of the above polymerization of only propylene, 1 g of the titanium compound was obtained at 70 ° C. for 30 minutes.
Per 340 g of propylene was polymerized. As a result, the polypropylene component in the block copolymer is
It is found to be 5.9 wt%.

The P-of the polyolefin obtained by the above polymerization
Xylene soluble content is 64.0wt%, average particle size is 430μ
It was m. A predetermined amount of the organic substance powder shown in Table 1 was added to 100 parts by weight of the polyolefin, and the mixture was stirred and mixed. The falling seconds of the mixed composition at 70 ° C. were measured, and the results are shown in Table 1.
It was shown to. Furthermore, 0.1 wt% of 1,3-bis- (t-butylperoxyisopropyl) -benzene as an antioxidant, an antioxidant, a heat stabilizer, a chlorine scavenger, and an organic peroxide was added to the mixed composition to give a diameter of 20 mmφ. It extruded at 250 degreeC using the extruder, and obtained the pellet. The results are shown in Table 1.

Examples 10 to 12 In the preparation of the polyolefin of Example 1, the conditions for propylene polymerization and propylene ethylene copolymerization were:
The same operation as in Example 1 was performed, except that the propylene polymerization time was 120 minutes and the propylene-ethylene copolymerization was 90 minutes. The results are shown in Table 1.

Comparative Examples 1 and 2 Using the polyolefins prepared in Examples 1 and 10, the same operations as in Examples 1 and 10 were performed except that the organic powder was not blended. The results are shown in Table 1.

Comparative Examples 3 to 11 Using the polyolefin prepared in Example 1, the same operation as in Example 1 was carried out except that the composition shown in Table 1 was used.

[0035]

[Table 1]

Claims (1)

[Claims] (1) 100 parts by weight of polyolefin particles having a room temperature p-xylene soluble content of 30% by weight or more (2) OH group-containing fatty acid salt of polyvalent metal, room temperature p-xylene soluble content of 10% by weight A polyolefin particle composition comprising 0.01 to 3.0 parts by weight of an organic powder having an average particle size of 50 μm or less selected from the group consisting of the following polyolefins and silicone resins.