JPH01163499A - Impeller made of polyolefin - Google Patents

Abstract

PURPOSE:To obtain an impeller excellent in its wear resistance and heat resistance and the like by forming the impeller in injection molding of polyolefin composition made of super molecular weight polyolefin and low molecular weight or high molecular weight polyolefin with a definite compounding rate. CONSTITUTION:An impeller made of polyolefin is made of super molecular weight polyolefin whose limited viscosity measured in 135 deg.C decalin solvent is 10-40dl/g and low molecular weight or high molecular weight polyolefin whose limited viscosity measured in 135 deg.C decalin solvent is 0.1-5dl/g. The super molecular weight polyolefin includes polyolefin which stays in a range of 15-40wt.% against the total weight of super molecular weight polyolefin and low molecular weight or high molecular weight polyolefin in its weight, in a range of 3.5-15dl/g in its limited viscosity measured in 135 deg.C decalin solvent and in a range below 4.5kg.cm in its solution torque.

Description

[Detailed Description of the Invention] The present invention relates to an impeller with excellent wear resistance, heat resistance, or sliding properties, and more specifically, to a water meter, an automatic stop faucet, a flow meter, etc. Alternatively, the present invention relates to a polyolefin impeller that is rotatably attached to a shaft of a building material or the like and that can rotate well without supplying or impregnating lubricant or the like.

Conventionally, an impeller rotatably held on a shaft has been equipped with a bearing made of soft metal or the like on the sliding part of the impeller body made of metal such as aluminum or stainless steel. Types coated with materials are known. However, metal impellers are heavy, and when these metal impellers are used in water meters, automatic stop faucets, flowmeters, construction materials, etc., the overall weight of these devices increases, which is undesirable. Further, in such metal impellers, the cutting process during manufacturing is complicated, and there is a risk that manufacturing costs will increase. Furthermore, especially in the case of an impeller used underwater, there is a problem that problems such as corrosion are likely to occur.

In order to overcome the disadvantages of metal impellers, recently, such impellers have been made of plastic. As the plastic constituting such an impeller, engineering plastics such as polyacetal resin, polyimide resin, and polycarbonate resin can be considered. However, such engineering plastics such as polyacetal resins and polyimide resins have problems in that they are expensive, inferior in economic efficiency, and have insufficient sliding properties.

In practice, therefore, impellers made of relatively inexpensive nylon 12 or polyester rubber coated with molybdenum to improve sliding properties to some extent have often been used.

However, impellers made of polyester rubber coated with molybdenum still have insufficient abrasion resistance, heat resistance, and sliding properties, and wear and tear may occur on the sliding parts of the impeller. There is a possibility that sliding performance between the impeller and the shaft to which it is rotatably attached deteriorates due to temperature rise due to frictional heat caused by sliding, etc., which may cause noise generation.

In order to eliminate such inconveniences, it is also conceivable to mold impellers used in such precision instruments and the like from ultra-high molecular weight polyolefin. Ultra-high molecular weight polyolefins, such as ultra-high molecular weight polyethylene, have superior impact resistance, heat resistance, abrasion resistance, sliding properties, chemical resistance, tensile strength, etc., compared to general-purpose polyolefins such as general-purpose polyethylene. It is conceivable that it could be used as an impeller in various devices. However, ultra-high molecular weight polyethylene has an extremely high melt viscosity and poor fluidity compared to general-purpose polyethylene, so it is extremely difficult to mold it by ordinary extrusion molding or injection molding, and most of it is molded by compression molding. Currently, only a small portion of the material is extruded into rod shapes at extremely low speeds.

If such ultra-high molecular weight polyethylene, which has poor melt flowability, is molded into an impeller shape by ordinary injection molding, shear fracture flow will occur during the process of filling the resin into the mold cavity, and the resulting molded crystal will be Mica-like delamination occurs, and not only is it impossible to obtain a molded product with the excellent properties of ultra-high molecular weight polyethylene, but the impeller is often inferior to impellers molded from general-purpose polyethylene.

The present invention has been made in view of these circumstances, and it provides a polyolefin that does not impair the excellent mechanical properties originally possessed by ultra-high molecular weight polyolefins, and does not cause delamination. Injection molding is possible, there is no need for molybdenum coating to improve sliding properties, there is no need to separately supply or impregnate lubricant, and it is relatively inexpensive, especially for impellers used in various equipment. The purpose of the present invention is to provide an impeller that has excellent wear resistance, heat resistance, impact resistance, or slidability, and has low noise, and is suitable for use as a motor.

In order to achieve this object, the polyolefin impeller according to the present invention is made of an ultra-high molecular weight polyolefin having an intrinsic viscosity of 10 to 40 dl/g measured in a 135°C decalin solvent and a 135°C decalin solvent. (1) The ultra-high molecular weight polyolefin consists essentially of a low molecular weight to high molecular weight polyolefin having an intrinsic viscosity of 0.1 to 5 d1/g as measured in a solvent; The weight is 15 to 40% based on the total weight of the high molecular weight polyolefin, and (i) the intrinsic viscosity [η
]c is 3.5~15dl! /g, and is characterized in that it is obtained by injection molding a polyolefin composition containing at least a polyolefin having (i) a melting torque T of 4.5 kg-am or less.

According to such a polyolefin impeller according to the present invention, a polyolefin composition can be injection molded without impairing the excellent mechanical properties inherent to ultra-high molecular weight polyolefin and without causing delamination. Therefore, it is possible to obtain an impeller with excellent wear resistance, heat resistance, impact resistance, and slidability at a relatively low cost. Furthermore, according to the present invention, the polyolefin impeller obtained by injection molding a polyolefin composition has sufficient sliding properties, and it is not necessary to coat the sliding part with molybdenum to improve sliding properties. There is no need to supply lubricant or impregnate oil. Furthermore, since the polyolefin impeller according to the present invention has excellent abrasion resistance, heat resistance, impact resistance, and sliding properties, the impeller is less prone to wear and tear, and moreover, it is less susceptible to wear and tear due to temperature rise inside the device. Moreover, the sliding properties between the impeller and the shaft to which it is rotatably attached will not deteriorate, and noise can be suppressed as much as possible.

``Skin Ω and body theory'' The present invention will be specifically explained below.

The polyolefin impeller according to the present invention is preferably used for, for example, a water meter, an automatic stop faucet, a flow meter, or a construction material, and is made by injecting a polyolefin composition containing at least the following polyolefin (A>) into a mold, for example. Obtained by molding.

, trv soil, = 7 Enyu A Above, the polyolefin (A) used in the present invention consists of an ultra-high molecular weight polyolefin and a low molecular weight to high molecular weight polyolefin. The following describes the high molecular weight polyolefin.

135 of the ultra-high molecular weight polyolefin used in the present invention
The intrinsic viscosity [η]U measured in °C decalin solvent is 10
~40 dfl/g, preferably 15-35 dl/g. This intrinsic viscosity [η] is 10 dJ! If it is less than 40 dN/g, the mechanical properties of the impeller as an injection molded product tend to deteriorate, which is undesirable. On the other hand, if it exceeds 40 dN/g, the appearance of the impeller as an injection molded product will deteriorate.
This is not preferable because it causes flow marks and delamination.

The intrinsic viscosity [η
] h is 0.1 to 5 (IQ/g, preferably 0.5 to 3
d, in the range of 1/g. This intrinsic viscosity [η]h is 0
．． If it is less than 1 dfI/g, the molecular weight is too low and there is a risk of bleeding on the surface of the impeller as an injection molded product, so it is undesirable. It is difficult to use a polyethylene injection molding machine as is, so it is not preferred.

The ultra-high molecular weight polyolefins and low molecular weight to high molecular weight polyolefins mentioned above include, for example, ethylene,
α of propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 4-methyl-1-pentene, 3-methyl-1-pentene, etc.
- Consists of homopolymers or copolymers of olefins. Among these, ethylene homopolymers or copolymers of ethylene and other α-olefins, with ethylene as the main component, are desirable.

In the polyolefin constituting the impeller according to the present invention, the ultra-high molecular weight polyolefin and the low-molecular weight to high-molecular weight polyolefin are such that the ultra-high molecular weight polyolefin has a weight of 15 to 40% relative to the total weight of both polyolefins.
In other words, the low molecular weight to high molecular weight polyolefins are present in such a proportion that they account for 85 to 60 weight percent of the total weight of both polyolefins. . The ultra-high molecular weight polyolefin as described above has a weight of 2% relative to the total weight of both polyolefins.
It is preferable that it is present in such a proportion that it accounts for 0 to 35% of the heavy groups. If the amount of ultra-high molecular weight polyolefin is less than 15% by weight, the resulting impeller as an injection molded product tends to have poor mechanical properties, which is undesirable.
If it exceeds 0% by weight, delamination occurs in the impeller as an injection molded product, and as a result, a molded product with good mechanical properties cannot be obtained, which is not preferable.

The polyolefin used in the present invention essentially consists of an ultra-high molecular weight polyolefin and a low to high molecular weight polyolefin, which are present in the above quantitative proportions.

Therefore, the polyolefin used in the present invention has 13
Intrinsic viscosity [η] measured in decalin solvent at 5°C. 3.
It is in the range of 5 to 15 dl/g, and the melting torque T (kg-
cm) is below 4.5 dazzle/1. Note that the melting torque T here is determined by the JSR Curastometer (Hiichu Kikai Kogyo K).
(manufactured by K), temperature 240°C, pressure 5kg/CXK,
This is a value measured under the conditions of amplitude 3° frequency 6 CP) f.

[η] above. If it is less than 3.5 dfl/g, the resulting impeller as an injection molded product may have poor mechanical strength, especially wear resistance, which is not preferable; on the other hand, [η].

If it exceeds 15 dJ2/g, delamination occurs in the resulting impeller as an injection molded product, resulting in a decrease in mechanical strength such as wear resistance, which is not preferable.

Moreover, if the melting torque T exceeds 4.5-.(1), it is not preferable because it will not bite into a normal screw during molding and injection molding will not be possible with a general-purpose injection molding machine.

The polyolefin used in the present invention is preferably [η
] c is in the range of 4.0 to 10d, 12/g.

The polyolefin used in the present invention can also be prepared by blending an ultra-high molecular weight polyolefin and a low-molecular weight to high-molecular weight polyolefin in the above proportions, but according to the studies of the present inventors, a specific high-molecular weight polyolefin Polyolefins obtained by the following multi-step polymerization method in which olefins are polymerized in multiple steps in the presence of a catalyst formed from an active solid titanium catalyst component and an organoaluminum compound catalyst component have excellent properties. I found out.

Such a multi-step polymerization method is carried out in the presence of a Ziegler-type catalyst formed from a highly active titanium catalyst component (a) containing magnesium, titanium and halogen as essential components, and an organoaluminum compound catalyst component (b). It is carried out by multistage polymerization of olefins. That is, in at least one polymerization step, the intrinsic viscosity is 10 to 406ρ.
/g of ultra-high molecular weight polyolefin, and in other polymerization steps, the olefin is polymerized in the presence of hydrogen to have an intrinsic viscosity of 0.1 to 5 dJ! /g of low molecular weight star to high molecular weight polyolefin.

The particular Ziegler type catalyst used is essentially a catalyst of a particular nature formed from a solid titanium catalyst component and an organoaluminum compound catalyst component. As the solid titanium catalyst component, it is preferable to use, for example, a highly active fine powder catalyst component with a narrow particle size distribution, an average particle size of about 0.01 to 5 μm, and several microspheres fixed to each other. It is. A highly active finely powdered titanium catalyst component having such properties is obtained, for example, in the solid titanium catalyst component disclosed in JP-A No. 56-811, by bringing a liquid magnesium compound into contact with a liquid titanium compound. When precipitating a solid product, it can be manufactured by strictly adjusting the precipitation conditions. Specifically, in the method disclosed in JP-A-56-811, a hydrocarbon solution in which magnesium chloride and a higher alcohol are dissolved and titanium tetrachloride are mixed at a low temperature, and then
When heating to about 100°C to precipitate a solid product,
A highly active finely powdered titanium catalyst component is prepared by coexisting a small amount of monocarboxylic acid ester of about 0.01 to 0.2 mol per 1 mol of magnesium chloride and performing the precipitation under strong stirring conditions. can do.

Further, if necessary, it may be washed with titanium tetrachloride.

In this way, a solid catalyst component having excellent activity and particle state can be obtained. Such catalyst components are
For example, it contains about 1% to about 6% titanium, halogen/titanium (atomic ratio) is about 5% to about 90%, magnesium/
Titanium (atomic ratio) ranges from about 4 to about 50.

Further, the slurry of the solid titanium catalyst component prepared as described above is subjected to a high-speed shearing treatment, and the particle size distribution is narrow and the average particle size is 0.01 to 5 μm.
, preferably in the range of 0.05 to 3 μrn, are also suitably used as the highly active finely powdered titanium catalyst component. Specifically, a method for high-speed shearing treatment is, for example, a method in which a slurry of a solid titanium catalyst component is treated in an inert gas atmosphere using a commercially available homomixer for an appropriate period of time. In this case, for the purpose of preventing deterioration of catalyst performance, it is also possible to adopt a method in which titanium and an equivalent molar amount of an organoaluminum compound are added in advance. Furthermore, it is also possible to adopt a method of filtering the slurry after treatment through a sieve to remove coarse particles. By these methods, the highly active fine powdered titanium catalyst component having the fine particle size can be obtained.

The polyolefin used in the present invention is produced by using the highly active finely powdered titanium catalyst component (a) and the organoaluminum compound catalyst component (b) as described above, together with an electron donor if necessary, and by using pentane, hexane, etc. It can be produced by slurry polymerizing an olefin in a hydrocarbon medium such as , heptane, kerosene, etc., usually at a temperature in the range of 0 to 100° C., in a multi-stage polymerization process of at least two stages.

Examples of the organoaluminum compound catalyst component (b) include trialkylaluminum such as triethylaluminum and triisobutylaluminum, siaaluminum chloride such as diethylaluminum chloride and diisobutylaluminum chloride, and alkylaluminum sesquichloride such as ethylaluminum sesquichloride. or a mixture thereof is preferably used.

In the multistage polymerization process of the olefin, a multistage polymerization apparatus in which at least two or more polymerization vessels are usually connected in series is employed, such as a two-stage polymerization method, a three-stage polymerization method,... an n-stage polymerization method. will be implemented. It is also possible to carry out a multi-stage polymerization method using a batch molding method in one polymerization tank. It is necessary to produce a specific amount of ultra-high molecular weight polyolefin in at least one polymerization tank of the multi-stage polymerization process. The polymerization step for producing the ultra-high molecular weight polyolefin may be a first stage polymerization step, an intermediate polymerization step, or a plurality of stages of two or more stages. It is preferable to produce an ultra-high molecular weight polyolefin in the first stage polymerization step because it facilitates the polymerization process and allows easy control of the physical properties of the resulting polyolefin. In the polymerization step, the polyolefin used in the present invention is
40% by weight, the intrinsic viscosity [η], (1% in decalin solvent)
It is necessary that the ultra-high molecular weight polyolefin is 10 to 40 dN/g (value measured at 35°C), and furthermore, it is 18 to 37 weight percent of the polyolefin used in the present invention, and 21 to 21% by weight of the polyolefin used in the present invention. ~35% by weight has an intrinsic viscosity [η] of 15 to 35 dl/g, especially 18 to 30
(Preferably, the ultra-high molecular weight polyolefin is 107 g. In this polymerization step,
The intrinsic viscosity of the ultra-high molecular weight polyolefin produced [η,
is less than 10 dll/g, and even if the ultra-high molecular weight polyolefin produced in the polymerization step is outside the range of 15 to 40% by weight, it is difficult to obtain an injection moldable polyolefin.

In the multi-stage polymerization process, in the polymerization process for producing an ultra-high molecular weight polyolefin, polymerization is carried out in the presence of a catalyst consisting of the highly active titanium catalyst component (a) and the organoaluminum compound catalyst component (b). Polymerization can be carried out by gas phase polymerization or liquid phase polymerization. In either case, in the polymerization step to produce the ultra-high molecular weight polyolefin, the polymerization reaction is optionally carried out in the presence of an inert medium. For example, gas phase polymerization is carried out in the presence of a diluent consisting of an inert medium, if necessary, and liquid phase polymerization is carried out, if necessary, in the presence of a solvent consisting of an inert medium.

In the polymerization process for producing the ultra-high molecular weight polyolefin, the highly active titanium catalyst component (a) is used as a catalyst, for example, about 0.001 to about 20 milligram atoms, preferably about 0.005 to about 10 milligrams of titanium atoms per medium 11. Milligram atoms, organoaluminum compound catalyst component (b),
The Al/Ti (atomic ratio) is preferably used in a ratio of about 0.1 to about 1000, particularly about 1 to about 500.

The temperature of the heavy metal process for producing the ultra-high molecular weight polyolefin is usually about -20 to about 120°C, preferably about 0°C.
to about 100°C, particularly preferably from about 5 to about 95°C. The pressure during the polymerization reaction is within a pressure range that allows liquid phase polymerization or gas phase polymerization at the above temperature, for example, atmospheric pressure to about 100 kg/cJ, preferably atmospheric pressure to about 5 kg/cJ.
0, g/ci range. In addition, the polymerization time in the polymerization step is such that the amount of prepolymerized polyolefin produced is approximately 1 milligram atom of titanium in the highly active titanium catalyst component.
000g or more, preferably about 2000g or more. Moreover, in the polymerization step, in order to produce the ultra-high molecular weight polyolefin, it is preferable to carry out the polymerization reaction in the absence of hydrogen. Furthermore, after carrying out the polymerization reaction, it is also possible to temporarily isolate and store the polymer under an inert medium atmosphere.

Inert media that can be used in the polymerization process to produce the ultra-high molecular weight polyolefin include, for example, propane, butane, pentane, hexane, heptane,
Aliphatic hydrocarbons such as octane, decane, kerosene; alicyclic hydrocarbons such as cyclopenkune, cyclohexane; aromatic hydrocarbons such as benzene, toluene, xylene; halogenated hydrocarbons such as dichloroethane, methylene chloride, chlorobenzene; Alternatively, a mixture thereof can be used. Particularly desirable is the use of aliphatic hydrocarbons.

In addition, when producing the polyolefin used in the present invention, hydrogen is A polymerization reaction of the remaining olefin is carried out in the presence of the olefin. If the polymerization process for producing an ultra-high molecular weight polyolefin is the first stage polymerization process, then the second stage and subsequent polymerization processes correspond to the polymerization process. If the polymerization step is located after the ultra-high molecular weight polyolefin producing polymerization step,
A polyolefin containing the ultra-high molecular weight polyolefin is supplied to the polymerization step, and when the polymerization step is located after a polymerization step other than the ultra-high molecular weight polyolefin-producing polymerization step, the low molecular weight or high molecular weight produced in the previous step is supplied. The polyolefin is fed and the polymerization is carried out in each case continuously. At that time, the polymerization step usually includes
Feedstock olefin and hydrogen are supplied. When the polymerization step is the first stage polymerization step, a catalyst consisting of the highly active titanium catalyst component (a) and the organoaluminum compound catalyst component (b) is supplied, and the polymerization step is the second stage polymerization step.
In the case of a polymerization step after the step, the catalyst contained in the polymerization product liquid produced in the previous step can be used as is, or the highly active titanium catalyst component (a) and/or the catalyst can be used as necessary. Alternatively, it is okay to additionally supplement the organic aluminum compound (b).

The low molecular weight to high molecular weight polyolefin thus obtained is 5 to 70% by weight, preferably 20 to 60% by weight, based on the total olefin components polymerized in the entire polymerization process.
, particularly preferably in an amount of 25 to 55% by weight.

The hydrogen supply ratio in the polymerization steps other than the ultra-high molecular weight polyolefin production polymerization step is usually 0.01 to 5 mols of hydrogen per mole of olefin supplied to each polymerization step.
0 mol, preferably in the range of 0.05 to 30 mol.

The concentration of each catalyst component in the polymerization liquid in the polymerization tank in the polymerization step other than the ultra-high molecular weight polyolefin production polymerization step is approximately 0.001 per polymerization volume IJ) of the treated catalyst in terms of titanium atoms. to about 0.1 milligram atom, preferably about 0.005 to about 0.1 milligram atom, and the AI/Ti (atomic ratio) of the polymerization system is about 1 to about 1000.
, preferably about 2 to about 500. For this purpose, an organoaluminum compound catalyst component (b) can be additionally used as necessary.

In addition, hydrogen/electron donors, halogenated hydrocarbons, etc. may be present in the polymerization system for the purpose of controlling the molecular weight, molecular weight distribution, etc.

The polymerization temperature is within a temperature range that allows slurry polymerization and gas phase polymerization, and is about 40°C or higher, more preferably about 50 to about 100°C.
A range of 0.degree. C. is preferred. Further, the polymerization pressure is, for example, atmospheric pressure to about 100 kg/d, particularly atmospheric pressure to about 50 kg/d.
A range of cJ is preferred. The amount of polymer produced is about 1000 per milligram atom of titanium in the titanium catalyst component.
It is preferable to set the polymerization time so that the amount of polymerization is at least 5,000 g, particularly preferably at least about 5,000 g.

Polymerization steps other than the polymerization step for producing an ultra-high molecular weight polyolefin can be similarly carried out by a gas phase polymerization method or a liquid phase polymerization method. Of course, it is also possible to employ different polymerization methods in each polymerization step. Among the liquid phase polymerization methods, a slurry suspension polymerization method is preferably employed.

In either case, the polymerization reaction is usually carried out in the presence of an inert medium in the polymerization step. For example, gas phase polymerization processes are carried out in the presence of an inert medium diluent, and liquid phase slurry suspension polymerization processes are carried out in the presence of an inert medium solvent.

Examples of the inert medium include the same inert media exemplified in the polymerization process for producing the ultra-high molecular weight polyolefin.

Polyolefin composition obtained in the final stage polymerization process [
η]. However, the melting torque is usually 3.5 to 15 d, 117 g, preferably 4.0 to 10 dl/g, and the melting torque is 4.5 kg-a.
The polymerization reaction is carried out so that y+ or less.

The multi-step polymerization method can be carried out in a batch, semi-continuous or continuous manner.

The olefins to which the multi-stage polymerization method can be applied include:
As mentioned above, ethylene, propylene, 1-butene, 1-
Pentene, 1-hexene, 1-octene, 1-decene,
α-olefins such as 1-dodecene, 4-methyl-1-pentene, and 3-methyl-1-pentene can be exemplified, and it can also be applied to a method for producing homopolymers of these α-olefins. It can also be applied to a method for producing a copolymer consisting of two or more mixed components. Among these α-olefins, ethylene or ethylene and other α-olefins
- It is preferable to apply the multi-step polymerization method to a method for producing an ethylene polymer having an ethylene component as a main component, which is a copolymer with an olefin.

A polyolefin composition suitable for producing a polyolefin impeller according to the present invention contains a sliding filler (B) in addition to the polyolefin (A>) as described above. But it's okay.

As the sliding filler (B), conventionally known sliding fillers can be used without particular limitation, but specifically the following compounds are used.

Graphite powder, polytetrafluoroethylene 7'i
PTFE), tetrafluoroethylene-hexafluoropropylene copolymer resin (FEP), tetrafluoroethylene-perfluoroalkoxyethylene copolymer resin (FA), trifluorochloride ethylene resin (1) CT
FE), tetrafluoroethylene-ethylene copolymer resin (E
TFE), fluororesin powder such as vinylidene fluoride resin, molybdenum fluoride powder, molybdenum sulfide powder, titanium oxide powder, polyphenylene sulfide resin powder, etc.

These sliding fillers (B) are preferably used in powder form, and the particle size is 0°01 to 5001 t m
Preferably it is 0.05 to lOO, tcm.

In the polyolefin composition constituting the impeller according to the present invention, the sliding filler (B) as described above is 1 to 70 parts by weight, preferably 3 to 50 parts by weight based on the polyolefin (A>100 parts by weight). Parts, more preferably 5 to 30 parts, are used.

The polyolefin composition constituting the polyolefin impeller according to the present invention may contain a fibrous filler (C) in addition to the polyolefin (A>).

As the fibrous filler (C), conventionally known fibrous fillers can be used without particular limitation, but specifically the following are used.

Glass fibers, carbon fibers, boron fibers, potassium titanate whiskers, metal fibers such as aluminum fibers, stainless steel fibers, etc.

Asbestos, aramid fiber, polyester fiber, polyamide fiber, etc.

These fibrous fillers (B) have a fiber diameter of 1 to 30
μrn is preferably 5 to 20 μm, and the fiber length is 100 μm.
0-10000μm preferably 3000-6000μm
and the aspect ratio is 33 to 10,000, preferably 1
It is desirable that it is 50-1200.

In the polyolefin composition constituting the impeller according to the present invention, the fibrous filler (C) as described above is 1 to 70 parts by weight, preferably 3 to 50 parts by weight, based on the weight of the polyolefin (A>100). More preferably, it is used in an amount of 5 to 30 parts by weight.

Phenol! r I D The polyolefin composition constituting the polyolefin impeller according to the present invention may contain a phenolic stabilizer (D) in addition to the polyolefin (A>).

As the phenolic compound, conventionally known compounds can be used without particular limitation, and specifically, the following compounds are used.

2.6-di-t-butyl-4-methylphenol, 2.
6-di-cyclohexyl-4-methylphenol, 2.
6-diisopropyl-4-ethylphenol, 2.6-
Di-amyl-4-methylphenol, 2.6-di-t-octyl-4-n-propylphenol, 2.6-
Dicyclohexyl-4-n-octylphenol, 2-isopropyl-4-methyl-6-t-butylphenol, 2-t-butyl-2-ethyl-6-t-octylphenol, 2-inbutyl-4-ethyl-6- t-hexylphenol, 2-cyclohexyl-4-n-butyl-6-improbylphenol, tetrakis[methylene(3,5-di-t-butyl-4-
Hydroxy) hydrocinnamate comethane etc.

Furthermore, a phenol compound having two or more phenol nuclei can also be used as the phenol stabilizer. Specifically, the following compounds are used as such phenolic compounds having two or more phenol nuclei.

2.2-methylenebis(4-methyl-6-t-butylphenol) 4.4°-butylidenebis(3-methyl-6-t-butylphenol) 4.4-thiobis(3-methyl-6-t-butylphenol) 2 .2'-thiobis(4-methyl-6-[-butylphenol) 1.3.5-trimethyl-2,4,6-tris(3,5
-di-1-butyl-4-hydroxyphenyl)benzylbenzene, 1.3.5-tris(2-methyl-4-hydroxy-5
-butylphenol)methane, tetrakis[methylene(3,5-di-tert-butyl-4-hydroxyphenyl)propionate comethane, β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid alkyl ester , 2.2°-oxamidobis[ethyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]. As the β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid alkyl ester, an alkyl ester having 18 or less carbon atoms is particularly preferred. Also, tetrakis[methylene(2,4-
di-t-butyl-4-hydroxyphenyl) propionate comethane, n-octadecyl-3-(4'-hydroxy-3,5-di-t-butylphenyl) propionate, 2,6-sheet t-butyl-p -cresol, 2.4.
6-tris(3',5-di-monobutyl-4'-hydroxybenzylthiono-1,3,5-triazine, 2,2
'-Methylenebis(4-methyl-6-t-butylphenol), 4.4'-methylenebis(2,6-di-t-butylphenol), 2.2-methylenebis[6-(1
-methylcyclohexyl)P-cresol], bis[3
, 5-bis(4-hydroxy-3-t-butylphenyl)butyric acid coglycol ester, 4,4゛-
Butylidene bis(6-1-butyl-m-cresol>
, 1,1,3-tris(2-methyl-4-hydroxy-
5-t-butylphenyl)butane, 1,3.5-tris(2,6-dimethyl-3-hydroxy-4-t-butylbenzyl)in cyanurate, 1,3.5-tris(3
, 5-di-t-butyl-4-hydroxybenzyl) -
2,4,6-trimethylbenzene, 1,3,5-tris(3,5-di-t-butyl-4-hydroxybenzyl)
insia nude, 1,3,5-tris [(3,5-di-
t-Butyl-4-hydroxyphenyl)propionyloxyethyl]isocyanurate, 2-octylthio-4
,6-di(4-hydroxy-3,5-di-t-butyl)
Phenoxy-1,3,5-triazine, 4,4'-thiobis(6-1-butyl-m-cresol), etc. are used.

These phenolic stabilizers may be used alone or in combination.

In the polyolefin composition constituting the impeller according to the present invention, the above-described phenolic stabilizer (B) is contained in an amount of 0.005 to 5 parts by weight, preferably 0.01 parts by weight, based on 100 parts by weight of the polyolefin (A). It is used in an amount of ~0.5 parts by weight, more preferably 0.05-0.2 parts by weight.

- Phosphite II E The polyolefin composition constituting the polyolefin impeller according to the present invention may contain an organic phosphite stabilizer (C) in addition to the polyolefin (A>).

As the organic phosphite stabilizer, conventionally known stabilizers can be used without particular limitation, but specifically the following compounds are used.

Trioctyl phosphite, trilauryl phosphite, tridecyl phosphite, octyl-diphenyl phosphite, tris(2,4-di-tert-butylphenyl)bosphite, triphenylphosphite, tris(butoxyethyl)bosphite, tris (nonylphenyl) phosphite, distearylpentaerythritol diphosphite, tetra(tridecyl')-1,
1,3-tris(2-methyl-5-tert-butyl-
4-hydroxyphenyl)butane diphosphite, tetra(C12-C15 mixed alkyl)-4,4'-isopropylidene diphenyl diphosphite, tetra(tridecyl)-4,4-butylidenebis(3-methyl-6-
ter't-butylphenol) diphosphite, tris(3,5-di-tert-butyl-4-hydroxyphenyl)phosphite, tris(mono-dimixed nonylphenyl)phosphite, hydrogenated-4,4°-isopropylidenediphenol Polyphosphite, bis(octylphenyl) bis[4,4°-butylidenebis(3-methyl-6-tert-butylphenol)] 1.6-
Hexaneoldiphosphite, phenyl 4,4°-
Isopropylidene diphenol pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis(
2,6-tert-butyl-4-methylphenyl)
Pentaerythritol diphosphite, tris[4,4
-isopropylidene bis(2-tert-butylphenol)] phosphite, phenyl diisodecyl phosphite, di(nonylphenyl) pentaerythritol diphosphite, tris(1,3-di-stearoyloxyisopropyl) phosphite, 4,4 °-isopropylidene bis(2-tert-butylphenol) di(
nonylphenyl) phosphite, 9,10-di-hydro-9-oxa-9-oxa-10-phosphaphenanthrene-10-oxide, tetrakis(2,4-di-t
ert-butylphenyl)-4,4°-biphenylene diphosphite I and the like.

Further, as the bis(dialkylphenyl)pentaerythritol diphosphite ester, a spiro type represented by the following formula (1) or a cage type represented by the formula (2) are also used. Mixtures of both isomers are usually used most often for economic reasons arising from the process of preparing such phosphite esters.

Here, R1 and R2 are preferably alkyl groups having 1 to 9 carbon atoms, particularly tert-butyl groups among branched alkyl groups, and the substitution position in the phenyl group is 2.
, 4th position is most preferred. A preferred phosphite ester is bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite.

These organic phosphite stabilizers may be used alone or in combination.

In the polyolefin composition constituting the impeller according to the present invention, the organic phosphite stabilizer (C) as described above is added in an amount of 0.00% per 100 parts by weight of the polyolefin (A>100 parts by weight).
It is used in an amount of 5 to 5 parts by weight, preferably 0.01 to 0.5 parts by weight, more preferably 0.05 to 0.2 parts by weight.

The polyolefin composition constituting the polyolefin impeller according to the present invention may contain an organic onythyl stabilizer (F) in addition to the polyolefin (A).

As the organic onythyl stabilizer, conventionally known stabilizers can be used without particular limitation, and specifically, the following compounds are used.

Polyhydric alcohols of dialkylthiodipropionates such as dilauryl, similystyl, and distearyl and alkylthiopropionic acids such as butyl, octyl, lauryl, and stearyl (e.g., glycerin, trimethylolethane, trimethylolpropane, pentalyl) Erythritol, trishydroxyethyl isocyanurate) (eg pentaerythritol tetralauryl thiopropionate).

More specifically, dilaurylthiodipropionate,
Simyristylthiodipropionate, distearylthiodipropionate, laurylstearylthiodipropionate, distearylthiodibutyrate, etc.

These organic 1,000-tonythyl stabilizers may be used alone or in combination.

In the polyolefin composition constituting the impeller according to the present invention, the above-described organic 1,000-onythyl stabilizer (I?) is added in an amount of 0.00% per 100 parts by weight of the polyolefin (A>100 parts by weight).
It is used in an amount of 5 to 5 parts by weight, preferably 0.01 to 0.5 parts by weight, and more preferably 0.05 to 0.2 parts by weight.

In addition to the above-mentioned polyolefin (A), a phenolic stabilizer (D), an organic phosphite stabilizer (E), and an organic thioether stabilizer (F) are added to the polyolefin composition constituting the impeller according to the present invention. , or more than one of these, the thermal stability and long-term heat resistance stability during injection molding will be improved; however, if a metal salt (G) of a higher fatty acid (described later) is added as a stabilizer, the injection molding will be further improved. A polyolefin impeller with excellent long-term thermal stability and long-term thermal stability can be obtained.

The polyolefin composition constituting the impeller according to the present invention contains, in addition to the polyolefin (A), metal salts of higher fatty acids such as stearic acid, oleic acid, lauric acid, capric acid, Magnesium salts, calcium salts of higher fatty acids such as araxic acid, palmitic acid, behenic acid,
Alkaline earth metal salts such as barium salts, cadmium salts,
Alkali metal salts such as zinc salts, lead salts, sodium salts, potassium salts, and lithium salts are used. Specifically, the following compounds are used.

Magnesium stearate, magnesium laurate,
Magnesium palmitate, calcium stearate,
Calcium oleate, calcium laurate, barium stearate, barium oleate, barium laurate, barium araxinate, barium behenate, zinc stearate, zinc oleate, zinc laurate, stearate, sodium stearate, palmitic acid Sodium, sodium laurate, potassium stearate, potassium laurate, 12-human o-4
such as calcium distearate.

These metal salts of higher fatty acids may be used alone or in combination.

In the polyolefin composition constituting the impeller according to the present invention, the metal salt (E) of a higher fatty acid as described above is 0.005 to 5 parts by weight, preferably 0.005 to 5 parts by weight, based on the polyolefin (A>100 parts by weight). It is used in an amount of 0.01 to 0.5 part by weight, more preferably 0.05 to 0.2 part by weight.

In addition, in the present invention, in addition to the above-mentioned components, the polyolefin composition constituting the impeller contains, for example, heat-resistant stabilizers, weather-resistant stabilizers, pigments, dyes, lubricants, flame retardants, neutron shielding agents, etc. The additives to be added and mixed can be added within a range that does not impair the purpose of the present invention.

As explained above, the polyolefin impeller according to the present invention can prevent delamination without impairing the excellent mechanical properties inherent to ultra-high molecular weight polyolefins. Since it can be easily obtained by injection molding a polyolefin composition without causing any formation, it is possible to obtain an impeller with excellent wear resistance, heat resistance, impact resistance, or sliding properties at a relatively low cost. become. Moreover, according to the present invention, the polyolefin impeller obtained by injection molding a polyolefin composition has sufficient sliding properties, so there is no need to coat molybdenum or the like in order to improve sliding properties. There is no need to separately supply or impregnate lubricant.

Furthermore, since the polyolefin impeller according to the present invention has excellent abrasion resistance, heat resistance, impact resistance, and sliding properties, it is difficult to cause wear and tear on the sliding parts of the impeller, and moreover, The sliding performance between the impeller and the shaft to which it is rotatably attached will not deteriorate due to temperature rises, etc., and noise can be suppressed as much as possible.

Therefore, when such impellers are used in water meters, automatic stop faucets, flow meters, construction materials, etc., it is possible to reduce the weight, cost, and noise of these devices. Become.

Agent: Patent Attorney: Shunbetsu Suzuki

Claims (1)

[Claims] 1) Intrinsic viscosity measured in decalin solvent at 135°C is 10
-40 dl/g ultra-high molecular weight polyolefin;
Intrinsic viscosity measured in decalin solvent at 35°C is 0.1-5
dl/g, and (i) the ultra-high molecular weight polyolefin is comprised essentially of a low molecular weight to high molecular weight polyolefin having an
(ii) the intrinsic viscosity [η]_c measured in a decalin solvent at 135°C is 3.5 to 15 dl;
/g, and (iii) the melting torque T is 4.5k.
A polyolefin impeller obtained by injection molding a polyolefin composition containing at least a polyolefin in the range of g·cm or less. 2) The above polyolefin is produced in at least one polymerization step in the presence of a Ziegler type catalyst formed from a highly active titanium catalyst component (a) containing magnesium, titanium and halogen as essential components and an organoaluminium compound catalyst component (b). In the step, olefins are polymerized to produce ultra-high molecular weight polyolefins with an intrinsic viscosity of 10 to 40 dl/g, and in other polymerization steps, olefins are polymerized in the presence of hydrogen to produce ultra-high molecular weight polyolefins with an intrinsic viscosity of 0.1 to 5 dl/g. The polyolefin impeller according to claim 1, which is manufactured by a multi-step polymerization method that produces a polyolefin having a molecular weight to a high molecular weight. 3) The polyolefin impeller according to claim 1 or 2, wherein the polyolefin composition contains a slidable filler. 4) Claim 3, wherein the slidable filler is graphite, fluororesin powder, molybdenum fluoride, molybdenum sulfide, or polyphenylene sulfide resin powder.
The polyolefin impeller described in . 5) The polyolefin impeller according to any one of claims 1 to 4, wherein the polyolefin composition contains a fibrous filler. 6) The fibrous filler is glass fiber, carbon fiber,
The polyolefin impeller according to claim 5, which is boron fiber, potassium titanate whisker, asbestos, metal fiber, aramid fiber, polyester fiber, or polyamide fiber. 7) The polyolefin impeller according to any one of claims 1 to 6, wherein the polyolefin composition contains a stabilizer. 8) The polyolefin impeller according to claim 7, wherein the stabilizer is a phenolic stabilizer, an organic phosphite stabilizer, an organic thioether stabilizer, or a metal salt of a higher fatty acid.