JPH08109288A - Polyolefin resin composition - Google Patents

Abstract

PURPOSE: To obtain a polyolefin resin composition having an excellent balance among impact resistance, rigidity, and molding appearance. CONSTITUTION: The composition comprises 100 pts.wt. olefin polymers consisting of 30-95wt.% polyolefin resin and 70-5wt.% olefin elastomer and 0.1-50 pts.wt. hydrogenated block copolymer which has a weight-average mol.wt. of 50,000-700,000 and has per molecule at least two polymer blocks in which the weight ratio of conjugated diene compound units to the other monomer units is 100/0 to 50/50 and the difference between the maximum content of conjugated diene units containing a vinyl bond and the minimum content thereof is 15wt.%, at least 80% of the olefinic bonds of the copolymer having been hydrogenated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyolefin resin composition having an excellent balance of impact resistance, rigidity and molding appearance.

[0002]

2. Description of the Related Art Polyolefin resins are used for moldability, toughness,
Since it has excellent water resistance, chemical resistance, etc., low specific gravity, and low cost, it has been widely used for various molded products, sheets, and the like. However, since the impact resistance, especially the impact strength at low temperature, is poor, the purpose of use may be limited. Therefore,
To remedy this problem, styrene-butadiene-
Many proposals have been made to compound a rubber component such as a hydrogenated product of a styrene block copolymer and an ethylene-α-olefin copolymer rubber. However, although these polyolefin-based resin compositions have improved impact resistance, their rigidity and molded appearance are deteriorated, which is not sufficient for practical use. In order to improve these, high molecular weight type ethylene-α-
The use of olefinic copolymers is considered. However, the use of a high molecular weight type as the rubber component is not preferable in practice because the dispersibility in the resin is poor.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional technical problems, and is made rigid by blending a polyolefin resin, an olefin elastomer, and a hydrogenated block copolymer having a specific structure. Another object of the present invention is to provide a polyolefin resin composition having an excellent balance of impact resistance and molding appearance.

[0004]

That is, the present invention relates to (III) conjugated diene based on 100 parts by weight of (I) polyolefin resin 30 to 95% by weight (II) olefin elastomer 70 to 5% by weight. At least two polymer blocks having a weight ratio of a compound to another monomer of 100/0 to 50/50 are present in the molecule, and the maximum content and the minimum content of the conjugated diene moiety having a vinyl bond in the polymer block. Difference of 15% by weight and a hydrogenated block copolymer having a weight average molecular weight of 5 to 700,000 obtained by hydrogenating 80% or more of the olefinic unsaturated bond in the block copolymer.
A polyolefin resin composition containing 1 to 50 parts by weight is provided. Hereinafter, the present invention will be described in detail.

Component (I) The polyolefin resin (I) contained in the composition of the present invention is obtained by polymerizing one or more olefin monomers by, for example, a high pressure polymerization method or a low pressure polymerization method ( (Co) polymer. Here, as the olefin monomer, ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 2-methyl-1-propene, 3-methyl-1-pentene, 4-methyl-1-pentene, 5-
Methyl-1-hexene, and mixtures thereof. Preferred (I) polyolefin resins include polyethylene (any of low density, medium density and high density), high molecular weight polyethylene, polypropylene, polybutene, polymethylpentene, polypropylene and ethylene,
Examples thereof include block copolymers or random copolymers of 1-butene with α-olefin, and these polyolefin resins may be a mixture of two or more kinds.

Component (II) The olefin elastomer (II) used in the present invention is a copolymer of α-olefins such as ethylene, propylene, 1-butene and 1-hexene, or a non-conjugated diene thereof. Or an homopolymer of a higher α-olefin such as 1-hexene. Among these, ethylene / propylene copolymer rubber, ethylene / 1-butene copolymer rubber, ethylene / propylene / 1-butene copolymer rubber, ethylene / propylene / non-conjugated diene copolymer rubber, ethylene / 1-butene / non-conjugated diene Ethylene copolymer rubber such as copolymer rubber is preferable. These olefin elastomers may be a mixture of two or more kinds. MFR of the elastomer (230
℃, 2.16kg load), preferably 5 (g / 10
Min) or less. The production of the olefin-based elastomer in the present invention is not limited at all.

Component (III) The hydrogenated block copolymer used as the component (III) of the present invention comprises a polymer block in which the weight ratio of the conjugated diene compound to the other monomer is 100/0 to 50/50. The difference between the maximum content and the minimum content of the conjugated diene moiety having at least two vinyl bonds in the polymer block is 15% by weight, and 80 of the olefinic unsaturated bonds in the block copolymer are contained. It is a hydrogenated block copolymer having a weight average molecular weight of 5 to 700,000, which is obtained by hydrogenating at least 100% by weight.

The conjugated diene compound used for the polymer block is 1,3-butadiene, isoprene, 2,3
-Dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 4,5-dimethyl-1,3-octadiene,
One or two or more of chloroprene and the like can be mentioned, but in order to obtain a hydrogenated block copolymer which can be industrially used and has excellent physical properties, 1,3-butadiene, isoprene and 1,3-pentadiene are used. Preferred are 1,3-butadiene and isoprene.

Further, other monomers may be used in the polymer block, and examples of the other monomer include styrene, t-butylstyrene, α-methylstyrene and p-.
Methylstyrene, divinylbenzene, 1,1-diphenylstyrene, N, N-diethyl-p-aminostyrene,
Examples thereof include vinyl pyridine, and styrene and α-methylstyrene are particularly preferable.

The weight ratio of the conjugated diene compound to the other monomer in the polymer block is 100/0 to 50/50,
It is preferably 100/0 to 60/40, and if it is outside this range, the glass transition temperature of the polymer block rises, and the mechanical properties and modifying effect of the hydrogenated block copolymer obtained are inferior, which is not preferable. Further, the hydrogenated block copolymer used in the present invention has a content (a) of a conjugated diene having a vinyl bond in a conjugated diene (co) polymer block having a minimum vinyl bond (hereinafter referred to as “block A”). The content [b] of the conjugated diene moiety having a vinyl bond in the conjugated diene (co) polymer block having the maximum vinyl bond (hereinafter referred to as “block B”) is (in this case, vinyl bond means 1,2 bond and It is necessary to satisfy [b]-[a] ≧ 15%, including a conjugated diene having 3,4 bonds. As a combination of [a] and [b], for example, [a] ≦ 20%, [b] = 35 to 60% [a] ≦ 20%, [b] ≧ 60% [a] = 30 to 45%, The case of [b] ≧ 60% is mentioned, and among these, is preferable, and the combination is particularly preferable. When [b]-[a] <15%, the balance between impact resistance and rigidity becomes insufficient, which is not preferable.

The block structure before hydrogenation of the hydrogenated block copolymer (III) used in the present invention may be any one as long as it satisfies the above requirements, for example, the general formula (AB) _n (A- B) _n- A (BA) _n- B (however, n is an integer greater than or equal to 1) etc. are mentioned, and other than this, A-C-B (However, C is The weight ratio of the conjugated diene compound to the other monomer in the polymer block is 100/0 to 50/50.
And a conjugated diene content [c] having a vinyl bond may be a structure such as a conjugated diene (co) polymer block satisfying [a] <[c] <[b]. Further, the block copolymer for obtaining the component (III) may be one in which the polymer molecular chain is extended or branched via a coupling agent residue as shown in the following formula. (AB) _m X (BA) _m X (A-B-A) _m X (B-A-B) _m X (A-C-B) _m X (however, A, B, and C are Same as above, m is an integer of 2 or more,
(X is a coupling agent residue)

As the coupling agent in this case, for example, 1,2-dibromoethane, methyldichlorosilane,
Trichlorosilane, methyltrichlorosilane, tetrachlorosilane, tetramethoxysilane, divinylbenzene, diethyl adipate, dioctyl adipate, benzene-1,2,4-diisocyanate, tolylene diisocyanate, epoxidized 1,2-polybutadiene, Examples include epoxidized linseed oil, tetrachlorogermanium, tetrachlorotin, and the like.

The content of the block A in the block copolymer as the component (III) is 5 to 90% by weight, preferably 5 to 90% by weight.
The content of the block B is 85% by weight and 95 to 10% by weight, preferably 95 to 15% by weight. When the content of the block A is less than 5% by weight or more than 90% by weight, the impact resistance improving effect of the composition is lowered.

The hydrogenated block copolymer used in the present invention has a weight average molecular weight of 5 to 700,000, preferably 5 to 65.
10,000, and more preferably 70 to 650,000. If it is less than 50,000, the effect of improving the impact resistance of the composition decreases, while
If it exceeds 0,000, the workability is deteriorated and the molded appearance of the composition is deteriorated.

The method for producing the hydrogenated block copolymer of the present invention may be any method, but in general, living anion polymerization is carried out in an organic solvent using an organic alkali metal compound as an initiator to give a block copolymer before hydrogenation. It is obtained by carrying out a hydrogenation reaction after obtaining.

As the organic solvent, hydrocarbon solvents such as pentane, hexane, heptane, octane, methylcyclopentane, cyclohexane, benzene, xylene and toluene are used. As the organic alkali metal compound that is a polymerization initiator, an organic lithium compound is preferable.
As this organic lithium compound, an organic monolithium compound, an organic dilithium compound, or an organic polylithium compound is used. Specific examples of these include ethyl lithium, n-propyl lithium, isopropyl lithium, and n.
-Butyllithium, sec-butyllithium, t-butyllithium, phenyllithium, hexamethylenedilithium, butadienyllithium, isoprenyldilithium, etc., and 0.02 per 100 parts by weight of the monomer.
It can be used in an amount of up to 0.4 parts by weight.

The content of the conjugated diene compound having a vinyl bond in block A and block B (hereinafter referred to as "vinyl bond content") can be adjusted by a Lewis base such as ether or amine, specifically diethyl ether or tetrahydrofuran. , Propyl ether, butyl ether, higher ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether,
Polyethylene glycol ether derivatives such as diethylene glycol dibutyl ether and triethylene glycol dimethyl ether, and examples of amines include tertiary amines such as tetramethylethylenediamine, pyridine, triethylamine and tributylamine, and they are used together with the above organic solvents.

Further, the polymerization reaction is usually carried out at -30 to +1.
It is carried out at 50 ° C. Further, the polymerization may be carried out while controlling it at a constant temperature or may be carried out at an elevated temperature. Any method may be used to form the block copolymer, but in general, the block A is first polymerized in the organic solvent using a polymerization initiator such as the alkali metal compound, and then the block B is polymerized. It may be a block copolymer containing blocks A and B.

By hydrogenating the block copolymer polymerized as described above, the hydrogenated block copolymer of the present invention (II) in which the double bond residue of the conjugated diene moiety is hydrogenated
I) is obtained. That is, the hydrogenated block copolymer of the present invention, the block copolymer thus obtained,
Dissolve in an inert solvent, 20-150 ° C, 1-100k
It is obtained by hydrogenation in the presence of a hydrogenation catalyst under pressurized hydrogen of g / cm ² G. At that time, 80% or more, preferably 90% or more, and more preferably 95% or more of the olefinic unsaturated bond in the block copolymer must be hydrogenated. If it is less than 80%, heat resistance,
Insufficient weather resistance. Inert solvents used for hydrogenation include hexane, heptane, cyclohexane,
Hydrocarbon solvents such as benzene, toluene and ethylbenzene, and polar solvents such as methyl ethyl ketone, ethyl acetate, ethyl ether and tetrahydrofuran are mentioned.

As the hydrogenation catalyst, dicyclopentadienyl titanium halide, nickel organic carboxylate,
A hydrogenation catalyst composed of an organic cobalt salt such as cobalt and an organometallic compound of Group I to III of the periodic table, carbon, silica, nickel supported on silica, diatomaceous earth, platinum, ruthenium, rhenium, a rhodium metal catalyst,
Examples thereof include metal catalysts such as cobalt, nickel, rhodium, and ruthenium complexes. Further, hydrogenated compounds such as lithium aluminum hydride and p-toluenesulfonyl hydrazide, and further Zr-Ti-Fe-V-Cr alloy, Zr-Ti-Nb-Fe-V-Cr alloy, LaNi.
A hydrogenation reaction using a hydrogen storage alloy such as _{5 is} also mentioned as a method for producing the hydrogenated block copolymer used in the present invention.

The hydrogenation rate of the conjugated diene moiety is determined by the hydrogenation catalyst,
It is adjusted by changing the amount of the hydrogenated compound added, the hydrogen pressure during the hydrogenation reaction, or the reaction time. From the hydrogenated block copolymer solution, the catalyst residue is removed if necessary, and a phenol-based or amine-based antioxidant is added to facilitate the hydrogenation block copolymer from the polymer solution. It can be isolated. Isolation of the hydrogenated block copolymer can be carried out, for example, by adding acetone or alcohol to the hydrogenated block copolymer solution to cause precipitation, and by pouring the polymer solution into hot water with stirring to remove the solvent by distillation. It can be performed by a method such as. The hydrogenated block copolymer of the present invention can be used as a modified hydrogenated block copolymer by introducing at least one kind of functional group into the hydrogenated block copolymer.

The composition of the present invention comprises (I) a polyolefin resin, (II) an olefin elastomer, and (II)
I) Made of hydrogenated block copolymer, and has rigidity, impact resistance,
The composition has an excellent balance of molding appearance. The blending ratio of the (I) polyolefin resin, the (II) olefin elastomer, and the (III) hydrogenated block copolymer in the present invention is 30 to 95% by weight of the component (I), preferably 5 parts.
0 to 90% by weight, component (II) 70 to 5% by weight, preferably 50 to 10% by weight, based on 100 parts by weight in total,
Component (III) 0.1 to 50 parts by weight, preferably 0.3
４５45 parts by weight. When the amount of the component (I) is less than 50% by weight, the rigidity is decreased, and when it exceeds 95% by weight,
When the composition is used, the effect of improving impact resistance is insufficient, which is not preferable. Further, when the content of the component (II) is less than 5% by weight, the effect of improving the impact resistance of the composition is insufficient, and when it exceeds 50% by weight, the rigidity is lowered and the object of the present invention can be achieved. It is not preferable because it does not exist. Furthermore, (II
When the amount of the component (I) is less than 0.1 parts by weight based on 100% by weight of the total amount of the components (I) + (II), the effect of improving the impact resistance of the composition is insufficient, and the amount is 50% by weight. If it exceeds the range, the rigidity is lowered and the object of the present invention cannot be achieved, which is not preferable.

The production of the composition of the present invention is not particularly limited, and known methods can be used. For example, the composition of the present invention can be obtained by kneading the components with various extruders, Banbury mixers, kneaders, rolls, etc. In order to achieve the object of the present invention, the component (II) is used. A method in which the components (III) and (III) are kneaded first and then the components (I) are kneaded is preferable.

In the composition using the hydrogenated block copolymer which is the component (III) of the present invention and the components (I) to (III), various additives such as an antiaging agent and a heat stabilizer may be added, if necessary. Agents, UV absorbers, stabilizers such as copper damage inhibitors, silica, talc, carbon, calcium carbonate, magnesium carbonate, glass fiber, carbon fiber, metal fiber, glass beads, mica, potassium titanate whiskers, aramid fiber, wood Fillers such as powder, cork powder, cellulose powder, and rubber powder can be blended and used. Also,
In the composition of the present invention, a plasticizer, an oil, a softening agent such as a low molecular weight polymer, etc. may be blended and used together with the above-mentioned additives.

[0025]

EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited to these examples as long as the gist of the present invention is not exceeded. Parts and% in the examples are by weight unless otherwise specified. In addition, various measurements in the examples were based on the following methods. Vinyl bond content The vinyl bond content was calculated by the Hampton method using infrared analysis. Hydrogenation rate The hydrogenation rate of the conjugated diene is 10 with ethylene tetrachloride as the solvent.
It was calculated from 0 MHz and ¹ H-NMR spectrum. Weight average molecular weight The weight average molecular weight (hereinafter, also referred to as “molecular weight”) was determined in terms of polystyrene using gel permeation chromatography (GPC). Izod impact strength Measured according to JIS K7110. Flexural modulus was measured according to JIS K7203. Molding appearance The molding appearance was visually evaluated according to the following criteria. ◯: Appearance is good. X: Poor appearance such as pearly luster, flow mark and rough surface.

Reference Example 1 (Production of hydrogenated block copolymer
Method) After charging 5 kg of degassed and dehydrated cyclohexane and 300 g of 1,3-butadiene into a 10 liter autoclave, 0.25 g of tetrahydrofuran and 0.50 g of n-butyllithium were added and the polymerization temperature was kept at 80 ° C. Isothermal polymerization was performed. After the polymerization conversion rate became almost 100%, the reaction liquid was cooled to 40 ° C., and 75 g of tetrahydrofuran and 700 g of 1,3-butadiene were added to carry out temperature rising polymerization. After the polymerization was completed, the living Li amount was measured and found to be 3.1 mmol. To this system, 0.56 g of benzophenone was added and stirred for 10 minutes.
From the change in the color of the polymer liquid, it was confirmed that there was no living polymer terminal lithium as a living anion.
Next, a reaction product prepared by reacting 3.51 g of benzophenone dissolved in 20 ml of cyclohexane and 1.20 g of n-butyllithium in advance under a nitrogen atmosphere for 10 minutes was charged, and bis (cyclopentadienyl) titanium dichloride (0.1%) was added. 52 g and 1.51 g of diethylaluminum chloride dissolved in 10 ml of toluene were mixed in advance under a nitrogen atmosphere, and the components were charged into an autoclave and stirred. Hydrogen gas was supplied at a pressure of 8 kg / cm ² G, and a hydrogenation reaction was performed at 90 ° C. for 1.5 hours. The hydrogenation rate of the obtained hydrogenated polymer was 98%, and the molecular weight was 301,000. Also, the 1,2-butadiene bond content of the 1,3-butadiene block measured at the end of the first stage 1,3-butadiene block polymerization was 15%,
As a result of calculation from the 1,2-vinyl bond content measured at the end of the polymerization of 1,3-butadiene in the first stage and the 1,2-vinyl bond in the first stage, the 1,3-butadiene block in the second stage Its 1,2-vinyl bond content was 80%.

Reference Examples 2 to 14 By the same method as in Reference Example 1, the monomer species, the amount of monomer, the amount of catalyst, the polymerization time, the polymerization temperature, etc. were adjusted so that each hydrogenated block copolymer shown in Tables 1 to 3 was obtained. It was prepared by varying the amount. The results are shown in Tables 1-3.

[Table 1]

[Table 2]

[Table 3]

Reference Example 15 (Ethylene / α-olefin
Method for producing polymer (EP-1)) Copolymerization was carried out using a continuous polymerization device having an internal volume of 5 liters. In a polymerization vessel sufficiently replaced with nitrogen gas, ethyl sesquialuminum chloride 15 mmol / Hr, oxyvanadium trichloride 1 mmol / Hr, n-hexane 4
Liter / Hr, propylene 2.5 normal liter /
Minutes, ethylene 5 normal liters / hr, and ethylidene morbornene 25 mmol / hr at a rate of 5 kgG / cm ² while maintaining the temperature at 35 ° C.
I tried to become. During the polymerization, the contents of the polymerization vessel are 2.
The reaction product was continuously withdrawn so that it was kept at 5 liters. The copolymer thus obtained was quenched with isopropyl alcohol, coagulated with alcohol containing an antioxidant, and dried on a hot roll at 100 ° C. The obtained ethylene / α-olefin / non-conjugated diene copolymer had a propylene content of 28% by weight and an MFR (230 ° C,
2.16 kg load) 0.3 (g / 10 minutes), iodine value 1
It was 5.

Reference Examples 16 to 22 (Ethylene / α-olefin
Method for producing vinyl copolymer (EP-2 to 5 and EB-1 to 3)
Method) In the same manner as in Reference Example 15, the type of monomer, the amount of monomer,
It was prepared by varying the amount of catalyst, polymerization time, polymerization temperature and the like. The results are shown in Table 4.

[Table 4]

Examples 1 to 9 The hydrogenated block copolymers obtained in Reference Examples 1 to 9 above, polypropylene resin (PP), ethylene / propylene copolymer (EP) and talc were mixed in a 4-liter Banbury kneader. Were mixed in the weight ratios shown in Tables 5-6. The mixed composition is cut into square pellets after sheeting,
A test piece for physical property evaluation was produced by injection molding. The results of physical property evaluation are shown in Tables 5-6. All of these examples are compositions using a hydrogenated block copolymer within the scope of the present invention, and are excellent in the balance of impact resistance, rigidity, and molding appearance.

[Table 5]

[Table 6]

Example 10 The hydrogenated block copolymer "S-" obtained in Reference Example 8 above
8 ”and an ethylene / propylene copolymer were mixed in a weight ratio shown in Table 5 using a 4 liter Banbury type kneader. Next, polypropylene resin and talc were added to the obtained mixture at the weight ratios shown in Table 6, and kneading was further performed. The mixed composition is formed into a sheet,
A rectangular pellet was cut and injection-molded to prepare a test piece for physical property evaluation. Table 6 shows the results of physical property evaluation.

Examples 11 to 17 The same procedure as in Example 1 was carried out, and all had excellent balance of impact resistance, rigidity and molding appearance. Table 9 shows the formulation and evaluation results.

[Table 9]

Comparative Examples 1 to 5 In the same manner as in Example 1, injection-molded products were prepared using the hydrogenated block copolymers shown in Table 3 and their physical properties were evaluated. The results are shown in Table 7. The composition using the hydrogenated block copolymer that does not meet the requirements of the present invention lacks the balance of impact resistance, rigidity and molding appearance.

[Table 7]

Comparative Examples 6 to 9 In the same manner as in Example 1, the hydrogenated block copolymer, polypropylene resin (PP), ethylene / propylene copolymer (EP) and talc were added in the weight ratios shown in Table 8. Mix and
An injection-molded article was produced and each physical property was evaluated. Comparative Example 6
The mixing ratio is outside the range of the present invention, and the rigidity is insufficient. In Comparative Example 7, instead of the hydrogenated block copolymer, a hydrogenated product of styrene-butadiene-styrene triblock copolymer [SEBS; manufactured by Shell Co., Ltd., Kraton G165.
0] is used, and Comparative Examples 8 and 9 are examples in which the hydrogenated block copolymer is not used, and both have poor impact resistance and rigidity balance.

[Table 8]

[0035]

According to the present invention, by blending a polyolefin resin, an olefin elastomer, and a hydrogenated block copolymer having a specific structure, a polyolefin resin having an excellent balance of impact resistance, rigidity, and molding appearance. A resin composition can be obtained. The composition of the present invention is
It is used as various molded products by injection molding, extrusion molding, vacuum molding, etc., taking advantage of its excellent characteristics, automobile interior and exterior materials, various electric and electronic parts, housings, industrial parts, stationery, medical materials, films, etc. It can be widely used for sheet products.

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Toru Shibata 2-11-24 Tsukiji, Chuo-ku, Tokyo Within Nippon Synthetic Rubber Co., Ltd. (72) In-house Hisao Ono 2-11-24 Tsukiji, Chuo-ku, Tokyo Within Japan Synthetic Rubber Co., Ltd. (72) Inventor Yasuhiko Takemura 2-11-24 Tsukiji, Chuo-ku, Tokyo Within Japan Synthetic Rubber Co., Ltd.

Claims (1)

[Claims] 1. (I) Polyolefin resin 30 to 9
5% by weight (II) Olefin-based elastomer 70 to 5% by weight to 100 parts by weight in total (III) A polymer block in which the weight ratio of the conjugated diene compound and the other monomer is 100/0 to 50/50. The difference between the maximum content and the minimum content of the conjugated diene moiety having at least two vinyl bonds in the polymer block is 15% by weight, and 80 of the olefinic unsaturated bonds in the block copolymer are contained. Hydrogenated block copolymer having a weight average molecular weight of 5 to 700,000, which is obtained by hydrogenating at least 0.1%.
A polyolefin resin composition containing 1 to 50 parts by weight.