JPH0370666B2 - - Google Patents

Description

[Detailed description of the invention]

<Industrial Field of Application> The present invention provides a material that exhibits excellent performance as a flap, ie, a mudguard, that prevents mud, water, etc. from being scattered by the wheels of automobiles, bicycles, etc. <Conventional technology> As high-speed vehicles have become popular in recent years, Matsudo Guard has shown a tendency to become more susceptible to damage and deterioration due to impacts such as pebbles and water splashes.Also, with the rapid increase in usage in remote areas, Matsudo Guard has become more susceptible to damage due to poor road conditions. Therefore, it is recognized that the wear and tear is relatively quick, especially in large transport vehicles. The performance required for Matsudo Guard is considered to be extremely diverse depending on the usage situation, but for example, in addition to tensile properties, bending resistance, abrasion resistance, etc., there are also flexibility, low temperature properties, heat resistance, oil resistance, etc. Excellence is required. Rubber-like sheets are usually used for conventional mudguards for automobiles and bicycles, and although various studies have been conducted on the shape and structure, there has been very little research on the material, and the results are not necessarily satisfactory in terms of durability. Nakatsuta. <Problems to be Solved by the Invention> The present invention provides a vehicle muzzle guard that improves the above-mentioned drawbacks and exhibits excellent performance in various types of durability. <Means for solving the problem> As a result of study, the present inventors found that a specific ethylene α
- It has been discovered that a mudguard having excellent performance can be obtained by using an olefin copolymer, and the present invention has been achieved. That is, the present invention provides the following (i) obtained by copolymerizing ethylene and an α-olefin having 3 to 12 carbon atoms in the presence of a catalyst consisting of a solid substance containing at least magnesium and titanium and an organoaluminum compound. Ethylene α with the properties of ~(iv)
-Regarding a vehicle muzzle guard using an olefin copolymer. (i) Melt index is 0.01 to 100g/10min,
Preferably 0.1 to 50 g/10 min, more preferably 0.5 to 20 g/10 min, (ii) Density of 0.860 to 0.910 g/cm ³ , preferably 0.880
~0.910g/ ^cm3 , more preferably 0.890~0.905
g/cm ³ , (iii) The maximum peak temperature in differential scanning calorimetry (DSC) is 100°C or higher, preferably 110°C.
°C to 125 °C, (iv) boiling n-hexane insoluble content of 10% by weight or more, preferably 30 to 97% by weight. The ethylene/α-olefin copolymer used in the present invention must satisfy all of the conditions (i) to (iv) above. [Condition (i)] First, the melt index (JIS K
6760) less than 0.01 g/10 min, the fluidity will be poor and the moldability will be poor, making it impossible to obtain a mudguard with a uniform thickness. On the other hand, if it exceeds 100 g/10 min, the tensile strength will be poor. [Condition (ii)] If the density (JIS K 6760) of (ii) is less than 0.860 g/cm ^{3 ,} the mat guard will be too soft, resulting in insufficient strength and a sticky surface; If it exceeds it, it becomes hard and lacks flexibility, which is undesirable. [Condition (iii)] The maximum peak temperature (Tm) determined by DSC in (iii) is a value that correlates with the crystal morphology, and if Tm is less than 100℃, the heat resistance and tensile strength of Matsudo Guard will be insufficient.
The surface becomes sticky, which is undesirable. [Condition (iv)] Next, the boiling n-hexane insoluble content is a guideline for the proportion of amorphous parts and the content of low molecular weight components, and when the insoluble content is less than 10% by weight, it is considered amorphous. This increases the amount of carbonaceous and low molecular weight components, leading to problems such as poor performance due to decreased strength, a sticky surface, and easy attachment of dust, and it becomes difficult to maintain the shape of the mud guard. In addition, the method of measuring DSC and boiling n-hexane insoluble content in the present invention is as follows. [Measurement method using DSC] Precisely weigh approximately 5 mg of a sample from a 100 μm thick hot press-molded film, set it in the DSC device, raise the temperature to 170°C, hold it at that temperature for 15 minutes, and then reduce the temperature to 2.5. Cool down to 0°C at a rate of °C/min.
Next, from this state, increase the temperature to 170°C at a rate of 10°C/min.
Measurement is performed by raising the temperature to . The maximum peak temperature (Tm) is the temperature at the top of the maximum peak that appears during the temperature increase from 0°C to 170°C. [Measurement method for boiling n-hexane insoluble matter] A sheet with a thickness of 200 μm is formed using a heat press, three sheets of 20 mm x 30 mm are cut out, and boiling n-hexane is extracted using a double-tube Soxhlet extractor. Extraction is carried out with hexane for 5 hours. Remove n-hexane insoluble matter and vacuum dry (7 hours, under vacuum, 50°C)
After that, the boiling n-hexane insoluble content is calculated using the following formula. Boiling n-hexane insoluble content (wt%) = extracted sheet weight / unextracted sheet weight x 100 (
Weight %) The ethylene/α-olefin copolymer of the present invention can exhibit desired performance by satisfying all of the above-mentioned properties. The α-olefin copolymerized with ethylene has 3 to 12 carbon atoms. Specifically, propylene,
Butene-1, 4-methylpentene-1, hexene-1, octane-1, decene-1, dodecene-1
etc. can be mentioned. Particularly preferred among these are propylene, 1-butene, 1-4-methylpentene, and 1-hexene. The α-olefin content in the ethylene/α-olefin copolymer is preferably 5 to 40 mol%. Below, ethylene used in the present invention and α-
A method for producing an olefin copolymer will be explained. First, the catalyst system used is one in which an organic aluminum compound is combined with a solid catalyst component containing at least magnesium and titanium, and examples of the solid catalyst component include magnesium metal, magnesium hydroxide, magnesium carbonate, magnesium oxide, and Magnesium, etc., and double salts, double oxides, carbonates, chlorides, or hydroxides containing magnesium atoms and metals selected from silicon, aluminum, and calcium, as well as these inorganic solid compounds as oxygen-containing compounds, Examples include those in which a titanium compound is supported by a known method on an inorganic solid compound containing magnesium, such as one treated or reacted with a sulfur-containing compound, an aromatic hydrocarbon, or a halogen-containing substance. Examples of the above oxygen-containing compounds include organic oxygen-containing compounds such as water, alcohol, phenol, ketone, aldehyde, carboxylic acid, ester, polysiloxane, and acid amide, and inorganic oxygen-containing compounds such as metal alkoxides and metal oxychlorides. can be exemplified. Examples of sulfur-containing compounds include thiol,
Examples include organic sulfur-containing compounds such as thioethers, and inorganic sulfur compounds such as sulfur dioxide, sulfur trioxide, and sulfuric acid. As aromatic hydrocarbons,
benzene, toluene, xylene, anthracene,
Examples include various monocyclic and polycyclic aromatic hydrocarbon compounds such as phenanthrene. Examples of the halogen-containing substance include compounds such as chlorine, hydrogen chloride, metal chlorides, and organic halides. Examples of the titanium compound include titanium halides, alkoxy halides, alkoxides, and halogenated oxides. Preferred titanium compounds are tetravalent titanium compounds and trivalent titanium compounds, and specific examples of tetravalent titanium compounds include the general formula Ti(OR) _o X _4-o (where R is 1 carbon number) ~20 alkyl, aryl, or aralkyl groups, and X represents a halogen atom.n
is 0≦n≦4. ) are preferred, and titanium tetrachloride, titanium tetrabromide, titanium tetraiodide, monomethoxytrichlorotitanium, dimethoxydichlorotitanium, trimethoxymonochlorotitanium, tetramethoxytitanium, monoethoxytrichlorotitanium, diethoxydichlorotitanium, Triethoxymonochlorotitanium, tetraethoxytitanium, monoisopropoxytrichlorotitanium, diisopropoxydichlorotitanium, triisopropoxymonochlorotitanium, tetraisopropoxytitanium, monobutoxytrichlorotitanium, dibutoxydichlorotitanium, monopentoxytrichlorotitanium, monophenol Examples include citrichlorotitanium, diphenoxydichlorotitanium, triphenoxymonochlorotitanium, and tetraphenoxytitanium. Examples of trivalent titanium compounds include titanium trihalides obtained by reducing titanium tetrahalides such as titanium tetrachloride and titanium tetrabromide with hydrogen, aluminum, titanium, or organometallic compounds of metals in groups ~~ of the periodic table. can be mentioned. Also, the general formula Ti(OR _{) n} A trivalent titanium compound obtained by reducing a tetravalent alkoxy titanium halide represented by . Among these titanium compounds, tetravalent titanium compounds are particularly preferred. Specific examples of these catalysts include, for example, MgO-RX-TiCl ₄ system (Japanese Patent Publication No. 51-3514), Mg-SiCl ₄ -ROH-TiCl ₄ system (Japanese Patent Publication No. 51-3514),
23864), MgCl ₂ −Al(OR) ₃ −TiCl ₄ system (Japanese Patent Publication No. 51-152, Japanese Patent Publication No. 52-15111),
MgCl ₂ −SiCl ₄ −ROH−TiCl ₄ system (Japanese Patent Application Laid-open No. 1983
106581), Mg(OOCR) ₂ −Al(OR) ₃ −TiCl ₄
system (Japanese Patent Publication No. 52-11710), Mg−POCl ₃ −
TiCl ₄ system (Special Publication No. 153/1983), MgCl ₂ −
AlOCl-Ticl ₄ series (Special Publication No. 54-15316),
MgCl ₂ −Al(OR) _o X _3-o −Si(OR′) _n X _4-n −TiCl ₄
(In the above formula, R, R' are organic residues,
represents a halogen atom) in combination with an organoaluminum compound is an example of a preferable catalyst system. Examples of other catalyst systems include solid catalyst components such as
An example is a catalyst system in which a reaction product of an organomagnesium compound such as a so-called Grignard compound and a titanium compound is used in combination with an organoaluminum compound. Examples of organomagnesium compounds include general formula RMgX,
Organomagnesium compounds such as R ₂ Mg, RMg (OR) (where R is an organic residue having 1 to 20 carbon atoms,
represents a halogen) and their ether complexes, or these organomagnesium compounds may be further combined with other organometallic compounds such as organosodium, organolithium, organopotassium, organoboron,
Those modified by adding various compounds such as organic calcium and organic zinc can be used. Specific examples of these catalyst systems include, for example:
RMgX-TiCl ₄ system (Special Publication No. 50-39470),
RMgX-phenol-TiCl ₄ system (Special Publication 1984-
12953), RMgX-halogenated phenol-TiCl ₄ system (Japanese Patent Publication No. 12954-1983), RMgX-
Examples include those in which an organoaluminum compound is combined with a solid catalyst component such as a CO ₂ -TiCl ₄ system (Japanese Unexamined Patent Publication No. 57-73009). In another catalyst system, a solid material obtained by contacting an inorganic oxide such as SiO ₂ or Al ₂ O ₃ with a solid catalyst component containing at least magnesium and titanium is used as a solid catalyst component. An example is a combination of organic aluminum compounds. As an inorganic oxide
In addition to SiO ₂ and Al ₂ O ₃ , CaO, B ₂ O ₃ , SnO ₂ and the like can be used, and double oxides of these oxides can also be used without any problem. Any known method can be used to bring these various inorganic oxides into contact with the solid catalyst component containing magnesium and titanium. That is, a method of reacting in the presence or absence of an inert solvent at a temperature of 20 to 400°C, preferably 50 to 300°C for usually 5 minutes to 20 hours, a method of co-pulverization, or a combination of these methods as appropriate. The reaction may be carried out by Specific examples of these catalyst systems include, for example, the SiO ₂ -ROH-MgCl ₂ -TiCl ₄ system (Japanese Patent Application Laid-Open No.
47407), _SiO2 -R-O-R'-MgO- _AlCl3
−TiCl ₄ system (JP-A-57-187305), SiO ₂ −
MgCl ₂ −Al(OR) ₃ −TiCl ₄ −Si(OR′) ₄ series (JP-A-Sho
58-21405) (in the above formula, R and R' represent hydrocarbon residues), in combination with an organic aluminum compound. In these catalyst systems, a titanium compound can be used as an adduct with an organic carboxylic acid ester, or the above-described magnesium-containing inorganic solid compound can be used after being brought into contact with an organic carboxylic acid ester. Moreover, there is no problem in using an organoaluminum compound as an adduct with an organic carboxylic acid ester. Furthermore, in all cases it is also possible to use catalyst systems prepared in the presence of organic carboxylic acid esters without any problems. Here, various aliphatic, alicyclic, and aromatic carboxylic esters are used as the organic carboxylic ester, and aromatic carboxylic esters having 7 to 12 carbon atoms are preferably used. Specific examples include alkyl esters of benzoic acid, anisic acid, toluic acid, such as methyl and ethyl. A specific example of an organoaluminum compound to be combined with the above-mentioned solid catalyst component is the general formula
R ₃ Al, R ₂ AlX, RAlX ₂ , R ₂ AlOR, RAl(OR)
An organoaluminum compound of X and R ₃ Al ₂ X ₃ (where R is an alkyl group, aryl group or aralkyl group having 1 to 20 carbon atoms,
R may be the same or different), and triethylaluminum, triethylaluminum,
triisobutylaluminum, trihexylaluminum, trioctylaluminum, diethylaluminium chloride, diethylaluminum ethoxide, ethylaluminum sesquichloride,
and mixtures thereof. The amount of organoaluminum compound used is not particularly limited, but is usually 0.1 to 1000% of the titanium compound.
Molar times can be used. Furthermore, by bringing the catalyst system into contact with an α-olefin and then using it in the polymerization reaction, the polymerization activity can be greatly improved and the system can be operated more stably than in the case of no treatment. Various α-olefins can be used as the α-olefin used at this time, but α-olefins having 3 to 12 carbon atoms are preferable, and α-olefins having 3 to 8 carbon atoms are more preferable.
-Olefins are preferred. Examples of these α-olefins include propylene, butene-
Examples include 1, pentene-1, 4-methylpentene-1, hexene-1, octene-1, decene-1, dodecene-1, and mixtures thereof. The temperature and time during contact between the catalyst system and the α-olefin can be selected within a wide range, for example, the contact treatment can be carried out at 0 to 200°C, preferably 0 to 110°C, for 1 minute to 24 hours. α to contact
-The amount of olefin can be selected from a wide range, but usually
It is desirable to treat 1 g of the solid catalyst component with 1 g to 50,000 g, preferably 5 g to 30,000 g of α-olefin, and react with 1 g to 500 g of α-olefin per 1 g of the solid catalyst component. At this time, the pressure at the time of contact can be arbitrarily selected, but it is usually desirable to contact under a pressure of -1 to 100 kg/cm ² ·G. In the α-olefin treatment, the entire amount of the organoaluminum compound used may be combined with the solid catalyst component and then brought into contact with the α-olefin, or a part of the organoaluminum compound used may be combined with the solid catalyst component. After combining with α
- The polymerization reaction may be carried out by contacting with olefin and adding the remaining organoaluminum compound separately during polymerization. Further, when the catalyst system and the α-olefin are brought into contact, there is no problem even if hydrogen gas coexists, and there is no problem even if other inert gases such as nitrogen, argon, helium, etc. coexist. The polymerization reaction is carried out in the same manner as the polymerization reaction of olefins using ordinary Ziegler type catalysts. That is, all reactions are carried out in a gas phase, in the presence of an inert solvent, or using the monomer itself as a solvent in a state substantially free of oxygen, water, etc. Olefin polymerization conditions are temperature 20-300℃, preferably 40-200℃
The pressure is normal pressure to 70 kg/cm ² ·G, preferably 2 kg/cm ² ·G to 60 kg/cm ² ·G. Although the molecular weight can be controlled to some extent by changing polymerization conditions such as polymerization temperature and catalyst molar ratio, it is effectively carried out by adding hydrogen to the polymerization system. Of course, a two-stage or more multi-stage polymerization reaction with different polymerization conditions such as hydrogen concentration and polymerization temperature can be carried out without any problem. The ethylene/α-olefin copolymer of the present invention is clearly distinguished from the ethylene/α-olefin copolymer obtained by using one containing vanadium as a solid catalyst component. Even if the monomers constituting the copolymer are the same and the density is the same, DSC
The copolymer of the present invention has a higher Tm than that of the copolymer of the present invention, and the insoluble matter in boiling n-hexane is 10% by weight or more in the copolymer of the present invention, whereas the latter has no insoluble matter or only a very small amount. be. Due to these differences in the copolymers themselves, when used in mudguards, the copolymers of the present invention have a better balance of performance, such as strength, flexibility, and temperature characteristics, than the latter. In the present invention, the above-mentioned specific ethylene
Polyolefins obtained by other methods may be appropriately blended into the α-olefin copolymer as long as the properties of the ethylene/α-olefin copolymer are not impaired. Examples of these other polyolefins include high-pressure polyethylene, ethylene-vinyl acetate copolymer, linear low-density polyethylene, propylene-butene-1 copolymer, styrene-butadiene block copolymer, and thermoplastic elastomers such as olefins. etc. The blending ratio of these is preferably 100 parts by weight or less with respect to 100 parts by weight of the ethylene/α-olefin copolymer. In addition, to the ethylene/α-olefin copolymer, stabilizers, antioxidants, ultraviolet absorbers, blowing agents, antistatic agents, flame retardants, dyes, pigments, talc, calcium carbonate, carbon black, Fillers such as silica and various fibers can be appropriately blended. In particular, the ethylene/α-olefin copolymer of the present invention can contain a larger amount of filler than conventional polyolefins. The mud guard of the present invention can be used alone or in a layered manner with a base material. Examples of the base material include woven fabrics and nonwoven fabrics. The strength of the mud guard is improved by laminating it with the base material. Various methods such as injection molding and extrusion molding can be used to manufacture the mud guard.
Note that when the ethylene/α-olefin copolymer is the main component and other compounds are blended, a kneading step is added. In the case of laminating with a base material, the Mudguard obtained in this way and the base material are stacked together and heat-pressed, or the ethylene/α-olefin copolymer or a compound containing this as a main component is melted using a calendar roll or the like. Objects can be laminated directly to the substrate. The thickness of the mound guard is determined as appropriate, but is preferably in the range of 0.5 to 10 mm. The surface of the mat guard can also be embossed or printed as appropriate. <Examples> Hereinafter, the present invention will be specifically explained with reference to Examples, but the present invention is not limited thereto. The physical properties in the Examples and Comparative Examples were measured by the following method. [Creation of test sheet] The resin composition was 2 mm thick and 150 mm long x 150 mm wide.
mm mold, preheated at 210℃ for 5 minutes, pressure molded at the same temperature for 5 minutes at 150Kg/cm ² , then 30℃,
It was cooled for 10 minutes under a pressure of 150 Kg/cm ² . 50 it
After annealing at ℃ for 20 hours, it was left at room temperature for 24 hours and its physical properties were measured. [Tensile strength] A test piece was prepared using a No. 3 dumbbell according to JIS K 6301, and a tensile speed of 50 mm/min was measured. [Hardness] A test piece was prepared according to JIS K 6301 and measured using a C-type tester. [Bending test] A test piece was prepared according to JIS K 6301, and measurement was performed using a Dematschier tester. [Oil resistance] A test piece was prepared according to JIS K 6301, and the volume change rate was determined using JIS No. 3 oil at 23°C for 22 hours. Example 1 Ethylene and butene-1 were copolymerized using a solid catalyst component obtained from substantially anhydrous magnesium chloride, 1,2-dichloroethane, and titanium tetrachloride, and a catalyst consisting of triethylaluminum to produce ethylene-butene. -1 copolymer was obtained. The ethylene content of this ethylene-butene-1 copolymer is 87.9 mol%, and the melt index is 1.0.
g/10min, density is 0.895g/cm ³ , DSC maximum peak temperature is 119℃, boiling n-hexane insoluble content is 72
It was in weight%. Table 1 shows the evaluation results of various physical properties. Example 2 Using the same catalyst as in Example 1, an ethylene-butene-1 copolymer was obtained. The ethylene content of this ethylene-butene-1 copolymer is 91.0 mol%, melt index (MI)
was 5.1 g/10 min, density was 0.903 g/cm ³ , maximum peak temperature on DSC was 121° C., and content insoluble in boiling n-hexane was 78% by weight. Table 1 shows the evaluation results of various physical properties.
It was shown to. Example 3 An ethylene-propylene copolymer was obtained by copolymerizing ethylene and propylene using a solid catalyst component obtained from substantially anhydrous magnesium chloride, anthracene, and titanium tetrachloride and a catalyst consisting of triethylaluminum. . This ethylene
The ethylene content of the propylene copolymer is 88.0 mol%, the MI is 1.0 g/10 min, the density is 0.901 g/cm ³ ,
The maximum peak temperature by DSC was 121°C, and the content insoluble in boiling n-hexane was 79% by weight. The evaluation results are shown in Table 1. Comparative Example 1 Physical properties were measured using a commercially available ethylene-propylene copolymer rubber (EP02P: manufactured by Nihon Gosei Rubber Co., Ltd.). The rubber MI of this copolymer is 1.9g/
10min, density is 0.864g/cm ³ , DSC maximum peak temperature is 32℃, boiling n-hexane insoluble content is 0% by weight
It was hot. The evaluation results are shown in Table 1. From Table 1, the results of Comparative Example 1 are inferior in tensile strength and elongation;
In addition, it has become clear that it is not desirable for severe applications such as mudguards because of its poor oil resistance. Comparative Example 2 Physical properties were measured using commercially available linear low-density polyethylene (Nisseki Linirex AF2320, manufactured by Nippon Petrochemicals Co., Ltd.). The MI of this polyethylene is 1.0
g/10min, density is 0.922g/cm ³ , maximum peak temperature of DSC is 123℃, boiling n-hexane insoluble content is 97
It was in weight%. The evaluation results are shown in Table 1.
Although such linear low-density polyethylene has excellent tensile strength and elongation, it is too hard, lacks flexibility, and has poor flexibility, so it is not necessarily desirable for uses such as mudguards.

[Table] Example 4 Ethylene-butene-1 copolymer 100 of Example 1
Blend 5 parts by weight of carbon black into 5 parts by weight, and use an extruder with a T-die to make a product with a thickness of 1.5 mm and a width of 60 cm.
I made a sheet with a length of 90cm. This seat was installed as a mound guard for the rear wheels of a large truck, and each part was inspected after driving approximately 50,000 km. As a result, no change was observed, and good results were obtained. <Effects of the Invention> As described above, since the mud guard of the present invention uses a specific ethylene/α-olefin copolymer, it has good flexibility, strength, and
It has an excellent balance of low-temperature properties, abrasion resistance, oil resistance, bending resistance, etc., and is expected to have superior durability compared to conventional rubber.

Claims (1)

[Claims] 1. In the presence of a catalyst consisting of a solid substance containing at least magnesium and titanium and an organoaluminum compound, ethylene and α having 3 to 12 carbon atoms
- The following (i) obtained by copolymerizing with olefin
Vehicle muzzle guard using ethylene/α-olefin copolymer having properties (iv): (i) Melt index 0.01-100g/10min (ii) Density 0.860-0.910g/cm ³ (iii) Differential scanning calorimetry Maximum peak temperature by measurement method (DSC): 100℃ or higher (iv) Boiling n-hexane insoluble content: 10% by weight or higher. 2. The vehicle muzzle guard according to claim 1, wherein the α-olefin in the ethylene/α-olefin copolymer is an α-olefin having 3 to 6 carbon atoms.