JP2990854B2 - Olefin copolymer rubber composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an olefin copolymer rubber composition containing a silica filler and titanium oxide having good tensile properties and coloring properties.

[0002]

2. Description of the Related Art Conventionally, in an olefin copolymer rubber composition containing a silica filler, in order to obtain excellent tensile properties, the reactivity with the silica filler is changed to an olefin copolymer rubber. What introduces the silyl group which has this is used. As a method for producing an olefin-based copolymer rubber into which a silyl group has been introduced, Japanese Patent Publication No. Sho 44-22501 is known.
No.

Embedded image (Where R is hydrogen or a C ₁ -C ₆ organic group, X is a halogen, n is a group of 0 to 2, y is an integer of 1 to 3, n +
y is equal to three. ) Is used as a copolymerization component. In addition, Tokiko Sho 58
JP-A-38443 discloses a compound represented by the general formula R _n SiX _4-n (where X is a highly hydrolyzable group other than an oxygen-containing group, n is an integer of 1 to 3, R is hydrogen and Or a group selected from the group consisting of unsubstituted alkyl, aryl, alkaryl, and arylalkyl cyclic or heterocyclic groups, wherein at least one of the R groups has an unsaturated carbon-carbon bond.) A production method using the indicated ethylenically unsaturated organosilane as a copolymerization component is described. Also, when coloring the olefin copolymer rubber compounded with the silica filler, if the coloring pigment is directly added, the transparency of the olefin copolymer rubber compounded with the silica filler is high, resulting in poor coloring. Awaken. Therefore, it is known that titanium oxide which is a white pigment is further added in order to prevent poor coloring.

[0003]

However, in the silyl group-containing olefin copolymer produced by the conventional technique, since the silyl group has a high degree of hydrolysis, it reacts with atmospheric water, It is hydrolyzed to silanol and easily dehydrated and condensed. For this reason, the portion that reacts with the silica-based filler is lost, and no improvement in the tensile properties of the copolymer is observed. Attempts have also been made to react lower alcohols, amines and carboxylic acids with the hydrolyzable functional groups in the silyl groups to prevent the formation of silanols. However, under the conditions for producing the copolymer, the bond generated by the reaction is unstable, and a stable copolymer cannot be produced. In order to solve this problem, when a stable bond is introduced at the time of production, when a silica-based filler is blended and kneaded, a bond between a silyl group and the silica-based filler is not formed, and tensile properties are not improved. No improvement is seen. On the other hand, when titanium oxide is added at the time of coloring, the coloring property of the olefin copolymer rubber containing the silica filler is improved, but the tensile properties are reduced.

[0004]

The present inventors have conducted intensive studies to overcome the above-mentioned problems, and as a result, have found that an olefin copolymer obtained by copolymerizing a silyl group-containing unsaturated compound represented by the general formula (4). It has been found that a copolymer obtained by reacting a polymer with an alcohol or an alkoxide represented by the general formula (5) is stable at the time of production and exhibits excellent tensile properties at the time of blending a silica-based filler. Furthermore, it has been found that when the copolymer is used, a decrease in tensile properties is small even when titanium oxide is blended, and the present invention has been achieved.

[0005] That is, the present invention provides a catalyst comprising a transition metal compound and an organometallic compound, comprising at least two kinds of olefin monomers, a non-conjugated diene and

Embedded image (However, R ¹ is a hydrocarbon group having 1 to 20 carbon atoms, X is any halogen among chlorine, bromine and iodine,
p is an integer of 0 to 5, q is an integer of 1 to 20, m is an integer of 0 to 2, and n is an integer of 1 to 3. Also, m + n = 3. ) Is copolymerized with a silyl group-containing unsaturated compound represented by the general formula

Embedded image (However, M is a hydrogen atom or an alkali metal of any of lithium, sodium and potassium, R ² , R ³ ,
R ⁴ , R ⁵ and R ⁶ are the same as R ¹ described above, or a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms containing a tertiary amino group, or a tertiary amino group. R ⁴ , R ⁵ ,
The total number of carbon atoms in R ⁶ is 3 or more. ) Containing at least 20% by weight of a silyl group-containing olefin copolymer having a content of bound silyl group-containing unsaturated compound of 0.5 to 5.0% by weight obtained by reacting with a compound represented by the general formula The specific surface area is 160 to 3 with respect to 100 parts by weight of the rubber component.
Provided is an olefin copolymer rubber composition containing 20 to 150 parts by weight of a silica-based filler of 50 m ² / g and 0 to 50 parts by weight of titanium oxide.

Hereinafter, the present invention will be described in more detail. The silyl group-containing olefin copolymer used in the present invention may be used alone in the rubber component, or may be used by blending with another rubber. However, it is necessary to contain the silyl group-containing olefin copolymer in an amount of 20% by weight or more. If it is less than 20% by weight, no improvement effect on silica reinforcement is observed.

In the present invention, the silica-based filler to be added to the rubber component containing the silyl group-containing ethylene copolymer has a specific surface area of 160 to 350 m ² / g, preferably ² to 200 m ² / g.
00 to 300 m ² / g. The specific surface area is 160m ² /
If it is less than g, the reaction efficiency with the silyl group is poor and the improvement in tensile strength is small. When the specific surface area exceeds 350 m ² / g,
The pore diameter of silica becomes small, and the reactivity with silyl groups is inferior, which is not preferable. Specific examples of the silica-based filler include Nipsil VN ₃ (manufactured by Nippon Silica), Carplex # 6
7 (manufactured by Shionogi Pharmaceutical) and Shilton A (manufactured by Mizusawa Chemical). The amount of the silica-based filler is 100
20 to 150 parts by weight, preferably 30 to 7 parts by weight based on parts by weight
0 parts by weight. If the amount of the silica-based filler is less than 20 parts by weight, the improvement of the physical properties is small, and if it exceeds 150 parts by weight, the processability is poor, which is not preferable. The amount of titanium oxide used in the present invention is 0 to 100 parts by weight of the rubber component.
It is 50 parts by weight, preferably 5 to 20 parts by weight. If it exceeds 50 parts by weight, the processability is poor and it is not preferable.

The catalyst used for producing the olefin copolymer in the present invention is a Ziegler-Natta catalyst comprising a transition metal compound and an organometallic compound. As the transition metal compound, a halogen compound of Ti, Zr, V, and Cr can be used, and a compound of Ti or V is particularly preferable. As the organometallic compound, an alkyl compound such as Al, Mg, and Li, or a haloalkyl compound is preferable.

Further, as the polymerization activity improver, halogenated acetates such as ethyl trichloroacetate, butyl trichloroacetate and dichloroacetic acid, butyl 1,1,2,3,3-pentachlorobutenoate, 1,1,2,2 Halogen-substituted butenoic acid esters such as ethyl 3-tetrachlorobutenoate,
Halogen-containing organic compounds such as α, α, α-trichlorotoluene and hexachlorobutadiene can be added. The olefin-based monomer used in the present invention includes ethylene, propylene, butene-1, pentene-
1, hexene-1, heptene-1, octene-1, nonene-1, decene-1, 4-methylpentene-1, 4-methylhexene-1, 4,4-dimethylpentene-1,5
-Methylheptene-1, 6-methylheptene-1 and the like, and it is preferable to use a mixture of ethylene and propylene or ethylene and butene-1. Preferred composition ratio of ethylene and propylene is ethylene 20 to
80 to 20 moles of propylene per 80 moles. The preferable composition ratio of ethylene and butene-1 is 10-50 mol of butene-1 to 90-50 mol of ethylene. On the other hand, as the non-conjugated diene used in the present invention, ethylidene norbornene, propenyl norbornene, dicyclopentadiene, 1,4-hexadiene,
4,7,8,9-tetrahydroindene and the like.

Next, as the silyl group-containing unsaturated monomer represented by the general formula (4) used in the present invention, for example, 5-trichlorosilyl-2-norbornene, 5-methyldichlorosilyl-2-norbornene, 5-dimethylchlorosilyl-2-norbornene, 2- (5-norbornenyl) ethylmethyldichlorosilane, 2- (5-norbornenyl) ethyldimethylchlorosilane, 2- (5-
Norbornenyl) propylmethyldichlorosilane, 2-
(5-norbornenyl) propyldimethylchlorosilane, 2- (5-norbornenyl) butylmethyldichlorosilane, 2- (5-norbornenyl) butyldimethylchlorosilane, (2-propenyl) dimethylchlorosilane, (2-propenyl) methyl Dichlorosilane, (3-
(Butenyl) dimethylchlorosilane, (3-butenyl) methyldichlorosilane, (3-butenyl) trichlorosilane, (4-pentenyl) dimethylchlorosilane, (4-
(Pentenyl) methyldichlorosilane, (4-pentenyl) trichlorosilane, (5-hexenyl) dimethylchlorosilane, (5-hexenyl) methyldichlorosilane, (5-hexenyl) trichlorosilane, (6-heptenyl) dimethylchlorosilane , (6-heptenyl) methyldichlorosilane, (6-heptenyl) trichlorosilane, (7-octenyl) dimethylchlorosilane, (7
-Octenyl) methyldichlorosilane, (7-octenyl) trichlorosilane and the like. Among the compounds represented by the general formula of Chemical Formula 4, among these compounds, (5
-Hexenyl) dimethylchlorosilane, (7-octenyl) dimethylchlorosilane, 5-methyldichlorosilyl-2-norbornene, 5-dimethylchlorosilyl-2-
Norbornene, 2- (5-norbornenyl) ethyldimethylchlorosilane and the like are particularly preferred.

Further, the alcohol represented by the general formula (I) used in the present invention includes phenol, o-cresol, m-cresol, p-cresol, o-ethylphenol, m-ethylphenol, p-ethylphenol, 3-dimethylaminophenol, 4-diethylaminophenol, 3-diethylaminophenol, 4-diethylaminophenol, 3-dimethylaminomethylphenol, 3-diethylaminomethylphenol, 2-
Methyl-2-propanol, 2-methyl-2-butanol, 2-methyl-2-pentanol, 6-diethylamino-2-hexanol, 6-dimethylamino-2-hexanol, 5-diethylamino-2-pentanol,
-Dimethylamino-2-pentanol and the like.
Examples of the alkoxide represented by the general formula 5 include lithium, sodium, and potassium salts of the above alcohol.

The polymerization solvent used in the present invention is not particularly limited, but includes, for example, n-pentane, n-hexane, cyclohexane, toluene, n-heptane and the like, with n-hexane being particularly preferred. The polymerization conditions are a temperature of -30 to 100C, preferably a temperature of 0 to 90C,
The pressure is 0 to 20 atm, preferably 0 to 10 atm. Next, when the reaction rate is sufficiently increased, the compound represented by the general formula (5) is added in excess to stop the polymerization reaction and to react with the silyl group introduced into the copolymer. A base such as triethylamine or pyridine may be used to promote the reaction. When the compound represented by the general formula of Chemical Formula 5 does not react with all silyl groups, a highly reactive lower alcohol such as methanol is used to prevent crosslinking.
Ethanol can also be added. Further, the unreacted monomer and the solvent are removed to obtain a silyl group-containing olefin copolymer.

The content of the non-conjugated diene in the obtained silyl group-containing olefin copolymer is 50 or less as an iodine value, preferably 5 to 40. If the iodine value exceeds 50, the ozone resistance deteriorates, which is not preferable. The content of the silyl group-containing unsaturated compound represented by the general formula (6) or (7) in the silyl group-containing olefin copolymer is 0.1%.
It is 5 to 5.0% by weight, preferably 1.0 to 3.0% by weight. If it is less than 0.5% by weight, the effect of improving the physical properties is small, and if it exceeds 5.0% by weight, the reaction with the silica-based filler proceeds too much and the rubber properties inherent in the copolymer are lost, which is not preferable. The Mooney viscosity (ML _{1 + 4} , 100 ° C.) of the silyl group-containing olefin copolymer is preferably in the range of 10 to 200, more preferably 20 to 100. If it is less than 10, the tensile properties are inferior, and it is not preferable.
If it exceeds, the processability is inferior and it is not preferable. Other rubbers that can be blended with the silyl group-containing olefin copolymer include other ethylene-propylene rubber, styrene-butadiene rubber, butadiene rubber, and natural rubber, and ethylene-propylene rubber is preferable.

The copolymer rubber composition of the present invention can be used as needed by blending an oil extender such as a paraffin-based process oil, other various compounding agents, and a vulcanizing agent, if necessary. Further, a filler such as carbon black may be mixed with the silica-based filler and used. The copolymer rubber composition of the present invention can be widely used for exterior parts for automobiles, rubber hoses, rubber sheets, vibration-proof rubbers, etc. by utilizing its excellent properties.

[0015]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the scope of the invention. Various measurements in the examples were based on the following. The propylene content, 1-butene content, and iodine value were calculated by an infrared method based on a calibration curve obtained in advance. The content of the silyl group-containing monomer is
Based on the absorption of the -Si-CH ₃ is observed near 1260 cm ^-1 in the infrared spectrum, to create a pre-calibration curve,
Determined by infrared method. The formation of diethylaminophenoxysilane or phenoxysilane by the reaction between the silyl group and 3-diethylaminophenol or phenol was confirmed by the GPC-UV method by observing a UV peak based on the phenoxy group.
Mooney viscosity was 1 minute for preheating, 4 minutes for measurement, and 100 for temperature.
Measured in ° C. The tensile properties are based on JIS K 6301
Compliant. The whiteness was measured with a Hunter colorimeter.

[Preparation Example 1] Purified n-hexane 3 in a 5-liter separable flask previously substituted with N ₂
The mixed gas of ethylene: propylene: hydrogen = 7: 8: 2 (molar ratio) was previously dissolved at room temperature.
Next, 2- (5-norbornenyl) ethyldimethylchlorosilane was added in the amounts shown in Tables 1 and 2, and further, ethyl aluminum sesquichloride (AlEt _1.5 C
l _1.5) was added 9.0mmol. Then 6.0 ml
Was slowly added by a feed pump while 0.9 mmol of VOCl ₃ was charged to initiate a polymerization reaction. During the polymerization reaction, a mixed gas of ethylene, propylene, and hydrogen is fed into the gas phase and stirred for 2 hours.
The polymerization was continued at 0 ° C. After a lapse of 30 minutes, a compound represented by the general formula (5) shown in Tables 1 and 2 was added. 1
After 0 minute, the amount of triethylamine shown in Table 1 and Table 2 was added, and the mixture was further stirred for 20 minutes. Then, 10 ml of dehydrated methanol was added. A large amount of methanol was added to the obtained copolymer solution for coagulation to obtain a copolymer, which was dried with a hot roll.

[Table 1]

[Table 2] The obtained copolymers are referred to as polymers A to G, J, and K. Tables 3 and 4 show the propylene content, iodine value, Mooney viscosity, and silyl monomer content. Further, under the same polymerization conditions, 9.0 mmol of 2- (5-norbornenyl) ethyldimethylchlorosilane was added, and after 30 minutes, isopropyl alcohol and benzyl alcohol were added, and the polymerization was terminated. H and I. Further, under the same polymerization conditions, the sample obtained by adding methanol after 30 minutes without adding the silyl group-containing monomer and terminating the polymerization is referred to as polymer L.

[Table 3]

[Table 4]

[Preparation Example 2] Purified n-heptane 3 in a 5-liter separable flask previously purged with nitrogen
The mixed gas of ethylene: 1-butene: hydrogen = 8: 1: 2 (molar ratio) was previously dissolved at room temperature.
Then, 2- (5-norbonenyl) ethyldimethylchlorosilane was added in the amounts shown in Table 2, and 10 mmol and 5 mmol of AlEt _1.5 Cl _1.5 and ethyl aluminum dichloride (AlEtCl ₂ ) were added, respectively. Next, while gradually adding 6.0 ml of ethylidene norbonene with a feed pump, 1.5 mmol of a reaction product of VOCl ₃ and ethyl alcohol (at a molar ratio of 1: 1) was added to initiate a polymerization reaction. During the polymerization reaction, a mixed gas of ethylene, 1-butene and hydrogen is fed into the gas phase, and the mixture is stirred at 40 ° C.
To continue the polymerization reaction. After 30 minutes, Table 2
Was added. Ten minutes later,
The amount of triethylamine shown in Table 2 was added and an additional 2
Stirred for 0 minutes. Then, 10 ml of dehydrated methanol was added. A large amount of methanol was added to the obtained copolymer solution for coagulation to obtain a copolymer, which was dried with a hot roll. The resulting copolymer was designated as Polymer M, and its 1-butene content, iodine value, Mooney viscosity, and silyl monomer content are shown in Table 4.

Examples 1 to 14 Polymers A, B, D to G, and J to M shown in Preparation Examples were kneaded in accordance with the formulation shown in Table 5, and vulcanized at 160 ° C. for 20 minutes. Table 6 shows the results of the physical property evaluation.

[Table 5]

[Table 6]

[Comparative Examples 1 to 9] The polymers A, C, H, I, and L shown in the preparation examples were kneaded according to the formulation shown in Table 5,
Vulcanized at 160 ° C. for 20 minutes. Table 7 shows the results of the physical property evaluation.

[Table 7]

[Examples 15 to 17] The polymer G shown in the preparation example was kneaded according to the formulation shown in Table 5 and vulcanized at 160 ° C for 20 minutes. The colorability of the copolymer was determined by the whiteness. The higher the whiteness, the better the coloring. Table 8 shows the tensile properties and whiteness of the vulcanizates.

[Table 8]

[0021]

As described above, the ethylene-based copolymer rubber composition of the present invention has excellent tensile properties as compared with conventional olefin-based copolymers containing a silica-based filler, and has good coloring properties. Is also excellent. Therefore, the olefin copolymer rubber composition of the present invention can be widely and effectively used for automobile exterior parts, hoses and the like.

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI (C08K 3/00 3:22 3:36) (72) Inventor Yuji Motomiya 2-1-1-24 Tsukiji, Chuo-ku, Tokyo Japan Gosei (56) References JP-A-1-110546 (JP, A) JP-A-63-238133 (JP, A) JP-A-63-225610 (JP, A) JP-A-47-12995 (JP, A) , A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08L 23/26-23/36 C08F 210/00-210/18 CA (STN) REGISTRY (STN)

Claims (1)

(57) [Claims] 1. Using a catalyst comprising (A) a transition metal compound and an organometallic compound, (a) at least two kinds of olefin monomers, (b) a non-conjugated diene, and (c) (However, R ¹ is a hydrocarbon group having 1 to 20 carbon atoms, X is any halogen among chlorine, bromine and iodine,
p is an integer of 0 to 5, q is an integer of 1 to 20, m is an integer of 0 to 2, and n is an integer of 1 to 3. Also, m + n = 3. ) Is copolymerized with a silyl group-containing unsaturated compound represented by the general formula: (However, M is a hydrogen atom, or an alkali metal of any of lithium, sodium and potassium, R ² , R ³ , R
⁴ , R ⁵ and R ⁶ are the same as R ¹ described above, or a hydrogen atom, a hydrocarbon group having 1 to 20 carbon atoms containing a tertiary amino group, or a tertiary amino group. Further, R ^4, R ^5, the total number of carbon atoms of R ⁶ is Ri der 3 or more, two simultaneous of R ^4, R ^5, R ⁶
Is not a hydrogen atom. A) a silyl group-containing olefin-based copolymer having a content of bound silyl group-containing unsaturated compound of 0.5 to 5.0% by weight, obtained by reacting with a compound represented by the general formula of at least 20% by weight; Rubber component 10
(B) Specific surface area is 160 to 350 m with respect to 0 parts by weight.
An olefin copolymer rubber composition containing 20 to 150 parts by weight of a ² / g silica filler and (C) 0 to 50 parts by weight of titanium oxide.