JP3535278B2 - Propylene-ethylene block copolymer - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a propylene-ethylene block copolymer, and more particularly to a propylene-ethylene block copolymer excellent in impact resistance, rigidity and moldability.

[0002]

BACKGROUND OF THE INVENTION Polypropylene is widely used in various fields because it is lightweight and has excellent mechanical strength and the like. However, when polypropylene is used as an automobile interior material or the like, impact resistance, rigidity and the like are not sufficient.

Various rubbers such as ethylene-propylene copolymer rubber (EPR) and an inorganic filler such as talc are added to a propylene-ethylene block copolymer for the purpose of improving impact resistance and rigidity. A polypropylene resin composition has been proposed. However, a resin composition obtained by adding a rubber component to a propylene-ethylene block copolymer is, when compared with polystyrene, ABS resin and the like,
There is a problem that impact resistance, rigidity, etc. are not sufficient, and the moldability decreases due to an increase in gel component, resulting in a poor appearance of the molded product. Further, by increasing the addition amount of the inorganic filler, impact resistance, rigidity and the like can be improved, but the surface smoothness of the molded product is deteriorated and it is disadvantageous in terms of cost and recycling.

In addition, as a method for obtaining a polypropylene resin composition having excellent impact resistance and rigidity, (1) a composition of titanium trichloride, (2) an organoaluminum compound and (3) S
A method of polymerizing propylene using a catalyst composed of an organosilicon compound having an i-O-C bond and / or a mercapto group (for example, JP-A Nos. 1-311106 and 1-318011).
And Japanese Patent Laid-Open No. 2-166104). However, in the case of manufacturing a large-sized molded product having a complicated shape by injection molding, it is necessary to improve fluidity and improve moldability.

As described above, a polypropylene resin composition having a good balance of impact resistance, rigidity and moldability has not yet been obtained. If these problems are solved, it is expected that the range of use of polypropylene-based resin materials will be expanded, the number of parts that can be covered with one material will increase, and that the development will be advantageous in terms of cost.

Therefore, it is an object of the present invention to provide impact resistance,
It is intended to provide a propylene-ethylene block copolymer having excellent rigidity and moldability.

[0007]

In view of the above object, the inventors of the present invention have conducted extensive studies and as a result, have found that a homopolypropylene portion having a constant relationship between the heat of fusion and the melt flow rate, and a propylene-containing low ethylene concentration. By producing a propylene-ethylene block copolymer consisting of an ethylene copolymerization portion and a propylene-ethylene copolymerization portion having a high ethylene concentration by multistage polymerization, a propylene-ethylene block excellent in impact resistance, rigidity and moldability is obtained. The inventors have found that a copolymer can be obtained and have arrived at the present invention.

That is, the propylene-ethylene block copolymer of the present invention is a propylene-ethylene block copolymer obtained by multistage polymerization, and (a) has a melt flow rate (MFR) measured according to ASTM D-1238. Is in the range of 1 to 1000 g / 10 minutes, and the heat of fusion (ΔH _m ) obtained from the differential scanning calorimetry and MFR satisfy the relational expression of ΔH _m ≧ 24.50 + 1.583 log MFR. % By weight, and (b) a low ethylene concentration propylene-ethylene copolymerization portion (ethylene content is 35 to 45 % by weight, intrinsic viscosity is 2 to 5).
dl / g. 2 to 38% by weight, and (c) a high ethylene concentration propylene-ethylene copolymerization portion (ethylene content is 50 to 90% by weight, intrinsic viscosity is 3 to 6).
dl / g. ) 2 to 38% by weight.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below. [1] Structure of Propylene-Ethylene Block Copolymer The propylene-ethylene block copolymer of the present invention has a substantially crystalline homopolypropylene portion, a low-ethylene concentration propylene-ethylene copolymer portion, and a high-ethylene concentration copolymer portion. A propylene-ethylene copolymerization portion and a small amount of a crystalline homopolyethylene portion,
Each part may exist as a single polymer, or each part may be in a bonded state.
The above-mentioned parts are basically composed of propylene and / or ethylene, but may contain a small amount of other α-olefin, diene-based monomer or the like.

(1) Crystalline homopolypropylene part The crystalline homopolypropylene part is ASTM D-12.
Melt flow rate (MFR) measured according to No. 38 (230 ° C., load 2.16 kg) is 1 to 1,000 g / 1.
It is 0 minutes, preferably 10 to 500 g / 10 minutes. MF
When R is less than 1 g / 10 minutes, the moldability is low, while 1.00
If it exceeds 0, the impact resistance decreases.

It is also necessary that the heat of fusion (ΔH _m ) obtained from the differential scanning calorimetry and MFR satisfy the relational expression ΔH _m ≧ 24.50 + 1.583 log MFR. ΔH _m <(2
4.50 + 1.583 log MFR), the rigidity and hardness are low.

The ΔH _m in the present invention is the heat of fusion measured while raising the temperature of the sample to 200 ° C.
The peak between 5 ° C and 175 ° C is taken as the melting peak, and the corresponding heat quantity is divided by the sample quantity to calculate the heat of fusion (unit cal / g).

(2) Low ethylene concentration propylene-ethylene copolymerization portion The ethylene content of the low ethylene concentration propylene-ethylene copolymerization portion is 20 to 50% by weight, preferably 35 to 50% by weight.
It is 45% by weight. When the ethylene content is less than 20% by weight, the elastic modulus is low, while when it exceeds 50% by weight, the ductility and impact resistance are deteriorated. Further, the intrinsic viscosity [η] _L of the propylene-ethylene copolymerization portion having a low ethylene concentration is 2 to 5 dl.
/ G, preferably 3 to 5 dl / g. When the intrinsic viscosity [η] _L is less than 2 dl / g, the effect of improving the rigidity is not sufficient, while when it exceeds 5 dl / g, the moldability decreases due to an increase in the gel component and the appearance of the molded product is poor. Becomes

(3) Propylene-Ethylene Copolymerization Part with High Ethylene Concentration The content of ethylene in the propylene-ethylene copolymerization part with high ethylene concentration is 50 to 90% by weight, preferably 55 to 50% by weight.
It is 65% by weight. If the ethylene content is less than 50% by weight, the impact resistance at low temperature is low, while if it exceeds 90% by weight, the ductility and impact resistance are reduced. The intrinsic viscosity [η] _H of the propylene-ethylene copolymerized portion having a high ethylene concentration is 3 to 6 dl / g, preferably 4 to 5 dl / g. When the intrinsic viscosity [η] _H is less than 3 dl / g, the impact resistance improving effect is not sufficient, while when it exceeds 6 dl / g,
The moldability decreases due to the increase of the gel component, and the appearance of the molded product becomes poor. From the viewpoint of improving impact resistance at low temperatures,
It is preferable that [η] _H is larger than [η] _L.

(4) Ratio Regarding the ratio of each of the above parts, the crystalline homopolypropylene part is 60 to 96% by weight, preferably 70 to 90% by weight, and the propylene-ethylene copolymer part having a low ethylene concentration is 2 to 2. It is 38% by weight, preferably 3 to 30% by weight, and the propylene-ethylene copolymerization portion having a high ethylene concentration is 2 to 38% by weight, preferably 3 to 30% by weight. Even if it contains a crystalline homopolyethylene portion, its content is 3% by weight or less based on the total propylene-ethylene copolymerization portion.

If the crystalline homopolypropylene portion is less than 60% by weight, the rigidity is low, while if it exceeds 96% by weight, the effect of improving mechanical strength and the like is not observed. When the propylene-ethylene copolymerized portion having a low ethylene concentration and the propylene-ethylene copolymerized portion having a high ethylene concentration are less than 2% by weight, ductility is low, while when it exceeds 38% by weight, impact resistance is lowered.

Considering the balance between ductility and impact resistance, the weight ratio of the low ethylene concentration propylene-ethylene copolymerization portion to the high ethylene concentration propylene-ethylene copolymerization portion is 1/9 to 9/1. Preferably 1/9 to 7
/ 3 is more preferable.

The contents of the low ethylene concentration propylene-ethylene copolymerization portion and the high ethylene concentration propylene-ethylene copolymerization portion (propylene-ethylene copolymerization portion) are determined by measuring the proportion of the soluble portion in cold xylene. Required by Further, the ethylene content of the propylene-ethylene copolymerized portion is determined by measuring the NMR spectrum.

[2] Production Method The propylene-ethylene block copolymer as described above is obtained by sequentially polymerizing a crystalline homopolypropylene portion, a low-ethylene concentration propylene-ethylene copolymer portion and a high-ethylene concentration. To be The polymerization order of each component in such multi-stage polymerization is not particularly limited, but from the viewpoint of productivity, first, a crystalline homopolypropylene portion (which may contain a small amount of comonomer component) is produced, and then the next step. It is preferable to switch to (ethylene + propylene) to produce a low-ethylene concentration propylene-ethylene copolymerization portion, and then produce a high-ethylene concentration propylene-ethylene copolymerization portion.

(1) Production of Crystalline Homopolypropylene Portion The crystalline homopolypropylene portion is not particularly limited in its production method as long as it satisfies the above-mentioned physical properties, but is preferably produced by the following method.

(I) Polymerization catalyst (A) A solid component containing magnesium, titanium, a halogen, and an electron-donating compound as essential components, (B) an organoaluminum compound, and (C) an organosilicon represented by the general formula (I). Compound and (D) optionally in the presence of an electron-donating compound,
(E) The catalyst component (hereinafter referred to as “preliminary polymerization catalyst component”) is obtained by prepolymerizing the olefin by contacting with the olefin.
Say. ) Is prepared, and an organometallic compound and, if necessary, an electron donating compound are combined therewith to obtain a propylene polymerization catalyst.

Here, the general formula (I) of the organosilicon compound of the component (C) is as follows.

[Chemical 1] (However, R ¹ is a cyclic substituent having an ether bond or a thioether bond in the ring, an oxy group having an in-ring ether bond-containing cyclic substituent, an in-ring ketone bond-containing cyclic substituent, a nitrogen atom-containing heterocyclic substituent. Group, a silicon atom-containing heterocyclic substituent, or a substituent having a lactone skeleton structure, R ² is a hydrocarbon group having 1 to 10 carbon atoms, R ⁴ O—,
R ⁵ Si- or R ⁶ ₃ SiO- (wherein R ⁴ is a hydrocarbon group having 3 to 10 carbon atoms, R ⁵ and R ⁶ are each a hydrocarbon group having 1 to 10 carbon atoms, R ³ is a methyl group or an ethyl group, x is 1 or 2, y is 0 or 1, and z is the same or different.
Is 2 or 3 and x + y + z = 4. )

(A) Solid component Solid component (hereinafter referred to as component (A)) is magnesium,
Titanium, a halogen and an electron donating compound are essential components, and usually prepared by contacting a magnesium compound, a titanium compound and an electron donating compound (in the case where each of the above compounds does not have a halogen, a halogen containing compound). be able to.

(A) Magnesium compound The magnesium compound is represented by the general formula MgR ⁷ R ⁸ . In the formula, R ⁷ and R ⁸ represent the same or different hydrocarbon groups, OR ⁹ groups (R ⁹ is a hydrocarbon group) or halogen atoms. More specifically, as the hydrocarbon of R ⁷ and R ⁸ , an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group,
Examples of the OR ⁹ group include an alkyl group having ⁹ to 12 carbon atoms, a cycloalkyl group, an aryl group, and an aralkyl group, and examples of the halogen atom include chlorine, bromine, and iodine. , Fluorine and the like.

Specific examples of these compounds are shown below (however, Me: methyl, Et: ethyl, Pr: propyl,
Bu: Butyl, He: Hexyl, Oct: Octyl, P
h: phenyl, cyHe: cyclohexyl. same as below. ). _{MgMe 2, Mg (i-Pr} ) 2, MgB
u ₂ , MgOct ₂ , MgEtBu, MgPh ₂ , Mg
cyHe ₂ , Mg (OEt) ₂ , Mg (OHe) ₂ , M
g (OOct) ₂ , Mg (OPh) ₂ , EtMgCl,
HeMgCl, i-BuMgCl, PhMgCl, Ph
CH ₂ MgCl, BuMgBr, BuMgI, EtOM
gCl, PhOMgCl, EtOMgBr, EtOMg
I, MgCl ₂ , MgBr ₂ , MgI ₂ .

The above-mentioned magnesium compound can be prepared from metallic magnesium or other magnesium compounds when the component (A) is prepared. As an example,
Magnesium metal, halogenated hydrocarbon and general formula: X ¹ _n M (OR ¹⁰ ) _mn (In the formula, X ¹ is a hydrogen atom, a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms, M is boron, carbon,
It is an aluminum, silicon or phosphorus atom, R ¹⁰ is a hydrocarbon group having 1 to 20 carbon atoms, m is the valence of M, and m> n ≧ 0. The method of contacting the alkoxy group-containing compound of 1) is mentioned.

X ^{1 in} the general formula of the alkoxy group-containing compound
And hydrocarbons of R ¹⁰ include methyl (Me), ethyl (Et), propyl (Pr), i-propyl (iP)
r), butyl (Bu), i-butyl (i-Bu), hexyl (He), octyl (Oct) and other alkyl groups, cyclohexyl (cyHe), methylcyclohexyl and other cycloalkyl groups, allyl, propenyl, butenyl, etc. Alkenyl group, phenyl (Ph), tolyl, aryl group such as xylyl group, phenethyl, aralkyl such as 3-phenylpropyl, and the like. Of these, an alkyl group having 1 to 10 carbon atoms is particularly desirable.

Specific examples of the alkoxy group-containing compound include C (OEt) ₄ , C (OP) when M is carbon.
r) ₄ , C (OBu) ₄ , C (OOct) ₄ , HC (O
Me) ₃ , HC (OBu) ₃ , HC (OPh) ₃ , Me
C (OEt) ₃ , EtC (OMe) ₃ , PhC (OE
t) ₃ , CH ₂ ClC (OEt) ₃ , MeCHBrC
(OEt) ₃ , ClC (OMe) ₃ , ClC (Oi-B
u) ₃ , BrC (OEt) ₃ , MeCH (OEt) ₂ ,
CH ₂ (OMe) ₂ , CH ₂ ClCH (OEt) ₂ , C
HCl ₂ CH (OEt) ₂ , CCl ₃ CH (OE
t) ₂ , CH ₂ BrCH (OEt) ₂ , PhCH (OE
t) _{2 and the} like, and when M is silicon, Si (O
Et) ₄ , Si (OHe) ₄ , HSi (OEt) ₃ , H
Si (OPh) ₃ , MeSi (OBu) ₃ , PhSi
(OEt) ₃ , CHCl ₂ Si (OEt) ₃ , BrSi
(OEt) ₃ , ClSi (OBu) ₃ , CHCl ₂ Si
H (OEt) ₂ , CCl ₃ SiH (OEt) ₂ , Me ₃
SiOEt _{2 and the} like, and when M is boron, B (OEt) ₃ , B (OBu) ₃ , B (OH
e) ₃ , B (OPh) _{3 and the} like, and when M is aluminum, Al (OMe) ₃ , Al (OEt)
₃ , Al (OHe) ₃ , Al (OPh) _{3 and the} like. Further, when M is phosphorus, P (OMe) ₃ , P
(OEt) ₃ , P (OHe) ₃ , P (OPh) _{3 and the} like can be mentioned.

As the magnesium compound, a group II or IIIa metal (M ') of the periodic table represented by the general formula: MgR ⁷ R ⁸ .p (M'R ¹¹ _q )
Complexes with organic compounds of can also be used. The metal M ′ is aluminum, zinc, calcium, etc., and R ¹¹ has 1 to 1 carbon atoms.
12 alkyl groups, cycloalkyl groups or aralkyl groups. Further, q represents the valence of the metal M ′, and p is 0.
A number from 1 to 10 is shown. Specific examples of the compound represented by M′R ¹¹ _q include AlMe ₃ , AlEt ₃ , and Al (i-B).
u) ₃ , AlPh ₃ , ZnMe ₂ , ZnEt ₂ , ZnB
u ₂ , ZnPh ₂ , CaEt ₂ , CaPh _{2 and the} like can be mentioned.

(B) Titanium compound As the titanium compound, divalent, trivalent and tetravalent titanium compounds can be used. For example, titanium trichloride, titanium tetrachloride, titanium tetrabromide, trichloroethoxy titanium, trichlorobutoxy titanium, dichlorodiethoxy titanium, dichlorodibutoxy titanium, dichlorodiphenoxy titanium,
Examples include chlorotriethoxy titanium, chlorotributoxy titanium, tetrabutoxy titanium and the like. Among these, tetravalent titanium halides such as titanium tetrachloride, trichloroethoxy titanium, dichlorodibutoxy titanium and dichlorodiphenoxy titanium are preferable, and titanium tetrachloride is particularly preferable.

(C) Electron-donating compound Examples of the electron-donating compound include carboxylic acids, carboxylic anhydrides, carboxylic acid esters, carboxylic acid halides, alcohols, ethers, ketones, amines and amides. , Nitriles, aldehydes, alcoholates, phosphorus bound to organic groups via carbon or oxygen,
Examples include arsenic or antimony compounds, phosphoamides, thioethers, thioesters, carbonates and the like. Of these, carboxylic acids, carboxylic acid anhydrides, carboxylic acid esters, carboxylic acid halides, alcohols and ethers are preferable.

Specific examples of the carboxylic acid include aliphatic monocarboxylic acids such as formic acid, acetic acid, propionic acid, butyric acid, valeric acid, acrylic acid, methacrylic acid and crotonic acid, malonic acid, succinic acid, adipic acid and maleic acid. Aliphatic dicarboxylic acids such as, tartaric acid and other aliphatic oxycarboxylic acids, cyclohexene monocarboxylic acid, alicyclic carboxylic acids such as cis-1,2-cyclohexanedicarboxylic acid, benzoic acid, toluic acid, anisic acid, cinnamic acid And aromatic polycarboxylic acids such as phthalic acid, naphthalic acid, trimellitic acid, trimesic acid, and mellitic acid. As the carboxylic acid anhydride, the acid anhydrides of the above carboxylic acids can be used.

As the carboxylic acid ester, the mono- or polyvalent esters of the above-mentioned carboxylic acids can be used, and specific examples thereof include butyl formate, ethyl acetate, isobutyl pivalate, ethyl acrylate, methyl methacrylate and malon. Diethyl succinate, dibutyl succinate, diisobutyl adipate, diethyl maleate, diisobutyl maleate, diethyl tartrate, diisobutyl tartrate, ethyl cyclohexanecarboxylate, methyl benzoate, ethyl benzoate, methyl p-toluate, ethyl p-anisate, Ethyl cinnamate, Monomethyl phthalate, Dibutyl phthalate, Diisobutyl phthalate, Diallyl phthalate, Diphenyl phthalate, Diethyl terephthalate, Dibutyl terephthalate, Diethyl naphthalate, Dibutyl naphthalate, Trie trimellitate Le, and the like.

As the carboxylic acid halide, acid halides of the above carboxylic acids can be used,
Specific examples thereof include acetic acid chloride, acetic acid bromide, acetic acid iodide, propionic acid chloride, butyric acid chloride,
Butyric acid bromide, butyric acid iodide, acrylic acid chloride, acrylic acid bromide, acrylic acid iodide, methacrylic acid chloride, methacrylic acid bromide, methacrylic acid iodide, crotonic acid chloride, malonic acid chloride, malonic acid bromide, succinic acid chloride, succinic acid bromide, Adipic acid chloride, adibic acid bromide,
Maleic acid chloride, maleic acid bromide, tartaric acid chloride, tartaric acid bromide, cyclohexanecarboxylic acid chloride, cyclohexanecarboxylic acid bromide, cis-4-
Methylcyclohexenecarboxylic acid chloride, cis-4-
Methylcyclohexenecarboxylic acid bromide, benzoyl chloride, benzoyl bromide, p-toluyl chloride, p-
Examples thereof include toluic acid bromide, p-anisic acid bromide, p-anisic acid chloride, cinnamic acid bromide, phthalic acid dichloride, phthalic acid dibromide, and naphthalic acid dichloride. Further, a monoalkyl halide of a dicarboxylic acid such as adipic acid monomethyl chloride, maleic acid monoethyl chloride and phthalic acid butyl chloride can also be used.

Alcohols are represented by the general formula R ¹² OH. In the general formula, R ¹² is an alkyl group having 1 to ¹² carbon atoms, an alkenyl group, a cycloalkyl group, an aryl group or an aralkyl group. Specific examples include methanol, propanol, isobutanol, pentanol, hexanol, cyclohexanol, benzyl alcohol, allyl alcohol, phenol, cresol, ethylphenol, n-octylphenol group and the like.

The ethers are represented by the general formula R ¹³ OR ¹⁴ . In the general formula, R ¹³ and R ¹⁴ are alkyl groups having 1 to 12 carbon atoms, alkenyl groups, cycloalkyl groups, aryl groups or aralkyl groups, and may be the same or different. Specific examples include diethyl ether, diisopropyl ether, diisoamyl ether, di-2-ethylhexyl ether, diallyl ether, butyl allyl ether, diphenyl ether, anisole group and the like.

(D) Halogen-containing compound Examples of the halogen-containing compound include halogenated hydrocarbons, halogen-containing alcohols, halogenated silicon compounds having a hydrogen-silicon bond, Group IIIa, Group IVa, and Va of the periodic table.
Halides of group elements (hereinafter referred to as metal halides)
Etc. can be mentioned.

The halogenated hydrocarbon has 1 to 10 carbon atoms.
Twelve saturated or unsaturated aliphatic, cycloaliphatic and aromatic hydrocarbon mono- and polyhalogen substitutes are mentioned. Specific examples of these compounds include, for aliphatic compounds, methyl chloride, methylene chloride, chloroform, iodoform, carbon tetrachloride, carbon tetraiodide, ethyl bromide, 1,2-dichloroethane, 1,2-diiodoethane, methyl. Examples include chloroform, 1,1,2-tribromoethylene, 1,1,2,2-tetrachloroethylene, pentachloroethane, hexachloroethane, hexachloropropylene, decabromobutane, chlorinated paraffin, and the like, alicyclic compounds. Include chlorocyclopropane, hexachlorocyclopentadiene, hexachlorocyclohexane, etc., and aromatic compounds include chlorobenzene, p-dichlorobenzene, hexachlorobenzene, hexabromobenzene, benzotrichloride, p-chlorobenzo. Trichlora De, and the like. These compounds may be used alone or in combination of two or more.

As the halogen-containing alcohol, one having one or two or more hydroxyl groups in one molecule or any one or two or more hydrogen atoms other than hydroxyl groups in the polyhydric alcohol are substituted with halogen atoms. It is a compound. Examples of the halogen atom include chlorine, bromine, iodine and fluorine atoms, and a chlorine atom is particularly desirable. Examples of these compounds include 2-chloroethanol, 1-chloro-2-propanol, 5-chloro-1-pentanol, 3-chloro-1,2-propanediol, 2-chlorocyclohexanol and 4-chlorobenz. Hydrol,
Chlorobenzyl alcohol, 4-chlorocatechol, 4
-Chloro-cresol, chlorohydroquinone, chlorophenol, 6-chlorothymol, 4-chlororesorcin, 2-bromoethanol, 1-bromo-2-butanol, 2-bromo-p-cresol, 1-bromo-2-naphthol, Fluorophenol, p-iodophenol, 2,2-dichloroethanol, 1,3-dichloro-
2-propanol, 2,3-dibromo-1-propanol, 2,4-dibromophenol, 2,2,2-trichloroethanol, 2,3,4-trichlorophenol,
2,4,6-tribromophenol, 2,3,5-tribromo-2-hydroxytoluene, 2,2,2-trifluoroethanol, 2,4,6-triiodophenol, 2,4,3,6 -Tetrafluorophenol, tetrachlorobisphenol A, 2,2,3,3-tetrafluoro-1-propanol, tetrafluororesorcin, and the like.

Examples of the silicon halide compound having a hydrogen-silicon bond include HSiCl ₃ , H ₂ SiCl ₂ and H
_{3 SiCl, H (C 2 H} 5) SiCl 2, H (t-C 4
H ₉ ) SiCl ₂ , H (C ₆ H ₅ ) SiCl ₂ , H (C
_{H 3) 2 SiCl, H (} i-C 3 H 7) 2 SiCl, H
_{2 (C 2 H 5) SiCl} , H 2 (n-C 4 H 9) SiC
1, H ₂ (C ₆ H ₄ CH ₃ ) SiCl, H (C ₆ H ₅ ).
₂ SiCl and the like can be mentioned.

As the metal halide, B, Al, Ga,
In, Tl, Si, Ge, Sn, Pb, As, Sb, B
Examples thereof include chloride, fluoride, bromide and iodide of i, and special BCl ₃ , BBr ₃ , BI ₃ , AlCl ₃ and Al.
_{Br 3, GaCl 3, GaBr 3} , InCl 3, TlC
l ₃ , SiCl ₄ , SnCl ₄ , SbCl ₅ , SbF ₅
Etc. are suitable.

(A) Magnesium compound, (b) titanium compound, (c) electron donating compound, and optionally (d) halogen-containing compound are mixed and stirred in the presence or absence of an inert medium. Or contact by mechanical co-milling. The contact can be performed under heating at 40 to 150 ° C. As the inert medium, saturated aliphatic hydrocarbons such as hexane, heptane and octane, saturated alicyclic hydrocarbons such as cyclopentane and cyclohexane, and aromatic hydrocarbons such as benzene, toluene and xylene can be used.

Component (A) in the present invention is the same as that described in JP-A-63-63.
No. 264607, No. 58-198503, No. 62-1
As disclosed in Japanese Patent No. 46904 and the like, magnesium metal, halogenated hydrocarbons and the general formula X ¹ _n M (O
A method of contacting a magnesium-containing solid obtained by contacting a compound of R ¹⁰ ) _mn (the same as the above-mentioned alkoxy group-containing compound) with a halogen-containing alcohol, and then with an electron-donating compound and a titanium compound (JP-A-2006-242242). 63-264607), a halogenated silicon compound having a hydrogen-silicon bond is brought into contact with a magnesium dialkoxide, and then a titanium halide compound is brought into contact with the electron donating compound (if necessary, further halogen A titanium halide compound) (JP-A-62-146904), a magnesium dialkoxide is contacted with a silicon halide compound having a hydrogen-silicon bond, then an electron donating compound, and then titanium. Method of contact with compound
No. 8-198503) and the like, but the most preferable method is.

The component (A) is prepared as described above, but the component (A) may be washed with the above-mentioned inert medium, if necessary, and further dried.

(B) Organoaluminum Compound Specific examples of the organoaluminum compound (hereinafter referred to as the component (B)) include trimethylaluminum, triethylaluminum, tripropylaluminum, triisopropylaluminum, tributylaluminum, triisobutylaluminum, triisobutylaluminum and triisobutylaluminum. Hexylaluminum and the like can be mentioned.

(C) Organosilicon Compound The organosilicon compound which is a component of the catalyst of the present invention (hereinafter referred to as component (C)) is represented by the above general formula (I).
In the formula, R ¹ is a cyclic substituent having an ether or thioether bond in the ring, an oxy group of a cyclic substituent having an ether bond in the ring, a cyclic substituent having a ketone bond in the ring, a heterocyclic substituent having a nitrogen atom, silicon An atom-containing heterocyclic substituent, a substituent having a lactone skeleton structure, R ² is a hydrocarbon group having 1 to 10 carbon atoms, R ⁴ O-, R ⁵ ₃ Si-
Or R ⁶ ₃ SiO— (provided that R ⁴ is a hydrocarbon group having 3 to 10 carbon atoms, R ⁵ and R ⁶ are each a hydrocarbon group having 1 to 10 carbon atoms), and R ³ is a methyl group or an ethyl group, x is 1 or 2, y is 0 or 1, z is 2 or 3, and x + y + z = 4. Specific examples of R ¹ are shown below (each R ¹ group is represented by RA, RB, ...).

[Chemical 2]

R ² in the above general formula of the component (C),
Examples of the hydrocarbon group in R ⁴ , R ⁵ and R ⁶ include an alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group, a cycloalkadienyl group, an aryl group and an aralkyl group. As the alkyl group, ethyl, i
-Propyl, s-butyl, t-butyl, amyl, 2-ethylhexyl, decyl group and the like, and the alkenyl group includes vinyl, allyl, propenyl, 1-hexenyl, 1-octenyl, 1-methyl-1-. Examples thereof include a pentynyl group, examples of the cycloalkyl group include a cyclopentyl group and a methylcyclohexyl group, examples of the cycloalkenyl group include a cyclopentenyl group and cyclohexenyl group, and examples of the cycloalkadienyl group include cyclopentadiene group. Examples of the aryl group include phenyl, tolyl, and a methylcyclopentadienyl group.
Examples thereof include a xylyl group and the like, and examples of the aralkyl group include a benzyl, phenethyl, 1-phenylpropyl group and the like.

Examples of the component (C) are shown below. [RA],
The symbols such as [RB] ... Correspond to the above symbols of R ¹ in the general formula (I) of the component (C). [RA] ₂ Si
(OMe) ₂ , [RB] (i-Pr) Si (OM
e) ₂ , [RC] (t-Bu) Si (OMe) ₂ , [R
C] (Me ₃ SiO) Si (OMe) ₂ , [RA] (i
-Pr) Si (OEt) ₂ , [RA] Si (OM
e) ₃ , [RD] Si (OMe) ₃ , [RB] Si (O
Et) ₃ , [RE] MeSi (OMe) ₂ , [RF]
(I-PrO) Si (OMe) ₂ , [RG] (i-P
r) Si (OEt) ₂ , [RH] Si (OMe) ₃ ,
[RI] Si (OEt) ₃ , [RJ] Si (OSiM
e) (OMe) ₂ , [RK] Si (OEt) ₃ , [R
L] Si (OEt) ₃ , [RM] Si (OEt) ₃ ,
[RN] Si (OEt) ₃ .

(D) The electron-donating compound component (D) comprises an organosilicon compound (component
(Except (C)) electron-donating compounds and electron-donating compounds containing heteroatoms such as nitrogen, sulfur, oxygen and phosphorus can be used, but organosilicon compounds are preferred. The organosilicon compound is preferably one having a total of 4 alkoxy groups (which may be partially substituted with an alkyl group or an aryl group) bonded to a silicon atom. These alkyl groups and alkoxy groups may be chain-like or cyclic. Further, the alkyl group or the aryl group may be substituted with a halogen element.

Such an organosilicon compound (component (D))
Specific examples of tetramethoxysilane, tetraisobutoxysilane, tetraphenoxysilane, tetrabenzyloxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltriphenoxysilane, ethyltriethoxysilane, butyltriethoxysilane,
Butyltriphenoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, dimethyldiisopropoxysilane, dimethyldiphenoxysilane, diethyldiethoxysilane, diethyldiisobutoxysilane, diethyldiphenoxysilane, dibutyldiisopropoxysilane, dibutyldibutoxysilane Silane, dibutyldiphenoxylan, diisobutyldiethoxysilane, diphenyldimethoxysilane, diphenyldibutoxysilane, dibenzyldiethoxysilane, divinyldiphenoxysilane,
Examples thereof include diallyldipropoxysilane, diphenyldiallyloxysilane, chlorophenyldiethoxysilane and the like.

Specific examples of the electron-donating compound containing a hetero atom include compounds containing a nitrogen atom:
6,6-tetramethylpiperidine, 2,6-diethylpiperidine, 2,6-diisobutyl-4-methylpiperidine, 2,2,5,5-tetramethylpyrrolidine, 3-methylpyridine, 2,6-diisobutylpyridine, 2,5
-Dimethylpiperidine, nicotinic acid amide, imidazole, benzoic acid amide, methyl nicotinate, 2-methylpyrrole, toluic acid amide, benzonitrile, acetonitrile, aniline, toluidine, triethylamine, tetramethylenediamine, tributylamine and the like, and sulfur. As a compound containing an atom, thiophenol,
Thiophene, ethyl 2-thiophenecarboxylate, methyl mercaptan, isopropyl mercaptan, diethyl thioether, diphenyl thioether, methyl benzene sulfonate, methyl sulfite and the like, and as the compound containing an oxygen atom, tetrahydrofuran, 2-methyltetrahydrofuran, 2, 2,5,5-tetraethyltetrahydrofuran, 2,2,6,6-tetramethyltetrahydropyran, dioxane, diethyl ether,
Examples thereof include diphenyl ether, anisole, acetophenone, acetone, o-tolyl-t-butyl ketone, and ethyl 2-furarate. Examples of the compound containing a phosphorus atom include triphenylphosphine, triphenylphosphite, and diethylphosphate.

Two or more kinds of these electron donating compounds (D) may be used. Further, these electron donating compounds may be added when the organoaluminum compound is used in combination with the catalyst component, or may be added after being brought into contact with the organoaluminum compound in advance.

(E) Olefin As olefins, in addition to ethylene, propylene and 1-
Α such as butene, 1-hexene, 4-methyl-1 penten
-Olefins can be used.

(Ii) Prepolymerization In the presence of an organoaluminum compound (component (B)) and an organosilicon compound (component (C)), a solid component (component (A)) is contacted with an olefin (component (E)). By doing so, the olefin is prepolymerized. Further, it is preferable to add an electron-donating compound (component (D)) together with the component (B) and the component (C) at the time of prepolymerization, if necessary. The prepolymerization is preferably carried out in the presence of the above-mentioned inert medium. The prepolymerization is usually performed at a temperature of 100 ° C or lower, preferably -30 ° C to +.
It is carried out at a temperature of 30 ° C, more preferably -20 ° C to + 15 ° C. The polymerization method may be a batch method or a continuous method, or may be a multi-step polymerization of two or more steps. When carrying out in multiple stages, it goes without saying that the polymerization conditions can be changed.

Component (B) has a concentration of 10 to 10 in the prepolymerization system.
It is used in an amount of 500 mmol / liter, preferably 30-200 mmol / liter, and is 1-50,000 mol, preferably 2-1,000 mol, per 1 gram atom of titanium in the component (A). To use. component
(C) is used so that the concentration in the prepolymerization system is 5 to 1,000 mmol / liter, preferably 10 to 200 mmol / liter. Further, the component (D) used as necessary has a concentration in the prepolymerization system of 1 to 100 mmol /
It is used in an amount of 1 liter, preferably 5 to 50 mmol / liter. Olefin polymer is incorporated into component (A) by prepolymerization, but the amount of polymer is
(A) 0.1 to 200 g per 1 g, especially 0.5 to 50 g is desirable. The catalyst component prepared as described above can be diluted or washed with the above-mentioned inert medium, but from the viewpoint of preventing storage deterioration of the catalyst component,
It is particularly desirable to wash. After washing, it may be dried if necessary. When storing the catalyst component, it is desirable to store it at a temperature as low as possible, such as -50 ° C to + 30 ° C.
In particular, a temperature range of -20 ° C to + 5 ° C is recommended.

(Iii) Main Polymerization The pre-catalyst component obtained as described above is combined with an organometallic compound and, if necessary, an electron donating compound, and homopolymerization of propylene or co-polymerization with other monoolefins is carried out. By performing main polymerization such as polymerization, it is possible to obtain crystalline polypropylene in which the relationship between the heat of fusion (ΔH _m ) determined by differential scanning calorimetry and MFR is represented by the above relational expression.

The organometallic compound that can be used in the main polymerization is an organic compound of Group I to Group III metal of the periodic table. As the organic metal compound, an organic compound of lithium, magnesium, calcium, zinc or aluminum can be used, and an organic aluminum compound is particularly preferable. The organoaluminum compound has the general formula: R ¹⁵ _r AlX ³ _3-r (wherein R ¹⁵ is an alkyl group or an aryl group, X ³ is a halogen atom, an alkoxy group or a hydrogen atom, and r is 1 ≦ r ≦ 3. And an alkylaluminum compound such as trialkylaluminum, dialkylaminium monohalide, monoalkylaluminum dihalide, dialkylaluminum monoalkoxide and alkylaluminum monohydride, Alternatively, a mixture or complex compound thereof is particularly preferable. The organoaluminum compound preferably has 1 to 18 carbon atoms, more preferably 2 to 6 carbon atoms.

Concretely, trialkyl aluminum such as trimethyl aluminum, triethyl aluminum and triisobutyl aluminum, dimethyl aluminum chloride, diethyl aluminum bromide, dialkyl aluminum monohalide such as diethyl aluminum iodide, methyl aluminum dichloride, ethyl aluminum dibromide. , Monoalkyl aluminum dihalides such as ethyl aluminum diiodide, alkyl aluminum sesquihalides such as methyl aluminum sesquichloride, diethyl aluminum ethoxide,
Examples thereof include dialkyl aluminum monoalkoxides such as diethyl aluminum phenoxide and diisobutyl aluminum ethoxide, and dialkyl aluminum hydrides such as dimethyl aluminum hydride, diethyl aluminum hydride and dipropyl aluminum hydride. Among these, trialkylaluminum is preferable, and triethylaluminum and triisobutylaluminum are particularly preferable. Further, these trialkylaluminums are other organic aluminum compounds, for example, industrially easily available diethylaluminum chloride, ethylaluminum dichloride, ethylaluminum sesquichloride, diethylaluminum ethoxide, diethylaluminum hydride or a mixture or complex compound thereof. Etc. can be used together.

It is also possible to use an organic alnium compound in which two or more aluminum atoms are bound to each other through an oxygen atom or a nitrogen atom. Examples of such compounds include

[Chemical 3] Etc. can be illustrated.

Examples of organic compounds of metals other than aluminum include diethyl magnesium, ethyl magnesium chloride and diethyl zinc. Further, as an organic compound of aluminum and another metal, LiAl (C
_{2 H 5) 4, LiAl (} C 7 H 15) 4 and the like.
The electron-donating compound that can be optionally combined with the prepolymerization catalyst component and the organometallic compound is an electron-donating compound (c) used when adjusting the component (A) and the component (A). It is appropriately selected from the electron-donating compounds (D) that may be used in the prepolymerization. Two or more kinds of these electron donating compounds may be used. Further, these electron donating compounds may be used when the organometallic compound is used in combination with the catalyst component, or may be used after being brought into contact with the organometallic compound in advance.

The amount of the organometallic compound used with respect to the pre-catalyst component is usually 1 to 2,000 gram moles, preferably 20 to 500 gram moles per gram atom of titanium in the catalyst component. When an electron donating compound is used, the amount of the organometallic compound (as aluminum) is 0.1 to 40 g atom, preferably 1 to 25 g atom per mol of the electron donating compound, so that the amount of the organo metal compound is 1 to 25 g atom. Select the ratio of electron-donating compounds.

The propylene polymerization reaction may be carried out in either a gas phase or a liquid phase. When the polymerization is carried out in the liquid phase, normal butane, isobutane, normal pentane, isopentane, hexane, heptane, octane, cyclohexane, benzene, toluene, It can be carried out in an inert hydrocarbon such as xylene and in a liquid monomer. The polymerization temperature is usually -8.
The temperature range is 0 ° C to + 150 ° C, particularly 40 ° C to 120 ° C. The polymerization pressure may be, for example, 1 to 60 atmospheres. Further, the molecular weight of the obtained polymer is controlled by the presence of hydrogen or other known molecular weight regulator. The polymerization reaction is carried out in a continuous or batch reaction, and the conditions may be those normally used. Also, the polymerization reaction may be carried out in one stage or in two stages.

(2) Formation of Propylene-Ethylene Copolymerization Portion After the crystalline homopolypropylene portion is formed, it is introduced by switching to (ethylene + propylene) in the presence of the polypropylene polymerization catalyst, Ziegler catalyst and the like. By adjusting the ratio of ethylene and propylene, a low-ethylene concentration propylene-ethylene copolymerization part and a high-ethylene concentration propylene-ethylene copolymerization part are produced in two stages. The polymerization order of these propylene-ethylene copolymerized portions is not particularly limited, but from the viewpoint of productivity, first, a low-ethylene concentration propylene-ethylene copolymerized portion is produced, and then a high-ethylene concentration propylene-ethylene copolymerized portion is produced. Is preferably produced.

The polymerization conditions in the propylene-ethylene copolymerization reaction can be appropriately selected from the range of the above-mentioned propylene polymerization conditions. The ethylene content of the propylene-ethylene copolymerization part is determined by sampling the reaction mixture and measuring the NMR spectrum.

[3] Additives The propylene-ethylene block copolymer of the present invention comprises
For the purpose of its modification, for example, a heat stabilizer, an antioxidant,
A light stabilizer, a flame retardant, a plasticizer, an antistatic agent, a release agent, a foaming agent, a coloring agent, a crystal nucleating agent, a pigment and the like can be added.

[0066]

EXAMPLES The present invention will be described in detail with reference to the following examples and comparative examples, but the present invention is not limited thereto. Example 1 of propylene-ethylene block copolymer (BPP1)
Preparation of Production Catalyst Component (A) In a 1 liter reaction vessel equipped with a reflux condenser, under a nitrogen gas atmosphere, chip-shaped metallic magnesium (purity 99.
5%, 8.3 g of average particle size 1.6 mm) and 250 ml of n-hexane were added, stirred for 1 hour at 68 ° C., metallic magnesium was taken out, and dried under reduced pressure at 65 ° C. to obtain pre-activated metallic magnesium. .

Next, 140 ml of n-butyl ether and an n-butyl ether solution of n-butyl magnesium chloride (1.
(75 mol / l) to a suspension of 0.5 ml
The temperature was maintained at 0 ° C., and a solution of 38.5 ml of n-butyl chloride dissolved in 50 ml of n-butyl ether was added dropwise over 50 minutes. After the reaction was carried out at 70 ° C for 4 hours with stirring, the reaction solution was kept at 25 ° C.

Next, HC (OC ₂ H ₅ ) ₃ was added to this reaction solution.
55.7 ml was added dropwise over 1 hour. 6 after the dropping
The reaction was carried out at 0 ° C. for 15 minutes, the reaction product solid was washed 6 times with 300 ml of n-hexane each time, dried under reduced pressure at room temperature for 1 hour, and a magnesium-containing solid containing magnesium 19.0% and chlorine 28.9% 31. 6 g was recovered.

In a 300 ml reaction vessel equipped with a reflux condenser, a stirrer and a dropping funnel, 6.3 g of magnesium-containing solid and 50 ml of n-heptane under a nitrogen gas atmosphere.
To prepare a suspension and stir at room temperature while stirring 2,2,2-
A mixed solution of 20 ml (0.02 mmol) of trichloroethanol and 11 ml of n-heptane was added from a dropping funnel to 30
The mixture was added dropwise over a period of 1 minute and further stirred at 80 ° C. for 1 hour. The solid obtained was filtered off and 100 ml of n-hexane at room temperature was added.
Was washed 4 times with 100 ml of toluene and then twice with 2 times to obtain a solid component.

40 ml of toluene was added to the above solid component, titanium tetrachloride was further added so that the volume ratio of titanium tetrachloride / toluene was 3/2, and the temperature was raised to 90 ° C. After stirring, a mixed solution of 2 ml of di-n-butyl phthalate and 5 ml of toluene was added dropwise, and then the mixture was stirred at 120 ° C. for 2 hours. The solid substance obtained was filtered off at 90 ° C.
Wash twice with ml at 90 ° C. Furthermore, titanium tetrachloride was newly added so that the volume ratio of titanium tetrachloride / toluene was 3/2, and the mixture was stirred at 120 ° C. for 2 hours, and the mixture was cooled to 100 at room temperature.
5. Catalyst component (A) after washing 7 times with ml of n-hexane 5.
5 g was obtained.

Prepolymerization (Preparation of prepolymerization catalyst component) In a 500 ml reactor equipped with a stirrer, under a nitrogen gas atmosphere, 3.5 g of the component (A) obtained above and 300 ml of n-heptane were put and stirred. While cooling to 5 ° C.
Next, n-heptane solution of triethylaluminum (TEAL) (2.0 mol / liter) and 2,3,4-trimethyl-3-azacyclopentyltrimethoxysilane were added to TEAL and 2,3,4-trimethyl in the reaction system. -3-Azacyclopentyltrimethoxysilane was added so that the concentrations thereof were 100 mmol / liter and 10 mmol / liter, respectively, and the mixture was stirred for 5 minutes.

Next, after depressurizing the system, propylene gas was continuously introduced to polymerize propylene for 2.2 hours. After completion of the polymerization, propylene in the gas phase was purged with nitrogen gas, and the solid phase portion was washed with 100 ml of n-hexane three times at room temperature. Further, the solid phase portion was dried under reduced pressure at room temperature for 1 hour to prepare a prepolymerization catalyst component. As a result of measuring the amount of magnesium contained in the prepolymerization catalyst component, the prepolymerization amount was 3.1 g per 1 g of the component (A).

In a 5-liter stainless steel autoclave equipped with a main polymerization stirrer, 4 ml of n-heptane solution of TEAL (0.3 mol / l) and n-heptane solution of diisopropoxydimethoxysilane (0 0.08 mol / liter) 3 ml were mixed and held for 5 minutes.

Then, hydrogen gas 1 was used as a molecular weight control agent.
After 0.5 liter and 3.0 liter of liquid propylene were press-fitted, the reaction system was heated to 70 ° C. After charging 120 mg of the prepolymerization catalyst component obtained above into the reaction system, 1
Polymerization of propylene (first-stage polymerization) was carried out for an hour. After the completion of the polymerization, unreacted propylene and hydrogen gas were purged until the pressure in the container reached 0.2 kg / cm ² · G.

After collecting a small amount of the first-stage polymer, hydrogen gas was introduced into the container. Then, a mixed gas having a molar ratio of propylene and ethylene of 1.91 was supplied to maintain the internal pressure of the container at 6.05 kg / cm ² · G, and the propylene-ethylene copolymerization (the Two-stage polymerization)
I went. 0.8 mol% in unreacted gas after polymerization
Contained hydrogen. After purging unreacted gas, a small amount of polymer was collected. After introducing hydrogen gas into the container again, a mixed gas with a molar ratio of propylene and ethylene of 0.49 was supplied, and the internal pressure of the container was 6.03 kg / cm ² ·.
While maintaining at G, propylene-ethylene copolymerization (third stage polymerization) was performed at 75 ° C. for 0.8 hours to obtain 462 g of a powdery propylene-ethylene block copolymer (BPP1). After the completion of the polymerization, the unreacted gas contained 0.4 mol% of hydrogen.

As a result of analyzing the collected polymer, the MFR of the obtained BPP1 was 28 g / 10 minutes, the homopolypropylene portion was 82% by weight, and the propylene-ethylene copolymerization portion having a low ethylene concentration was 6% by weight. Yes, the propylene-ethylene copolymerization portion of high ethylene concentration is 12
% By weight.

Homopolypropylene MFR (230
C., load 2.16 kg) was 130 g / 10 minutes, and differential scanning calorimetry (7700 Data Stat) was used.
ion, manufactured by Perkin-Elma Co., Ltd.), the heat of fusion (ΔH _m , heating rate 20 ° C./min) is 28.1 cal / g.
And the calculated value of the heat of fusion (ΔH _m ') calculated by (24.50 + 1.583 log MFR) is 27.8.
Met.

The ethylene content of the propylene-ethylene copolymerized portion having a low ethylene concentration was 35% by weight, and the ethylene content of the propylene-ethylene copolymerized portion having a high ethylene concentration was 65% by weight. Also, the intrinsic viscosity [η] _L of the propylene-ethylene copolymerized portion having a low ethylene concentration is 3
It was dl / g, and the intrinsic viscosity [η] _H of the propylene-ethylene copolymerization portion having a high ethylene concentration was 5 dl / g.

Furthermore, regarding BPP1, ASTM D6
38, the tensile elongation at break measured at room temperature is 90%, the flexural modulus measured at room temperature by ASTM D790 is 12600 kg / cm ² , ASTM D25
6, the Izod impact strength measured at 23 ° C. and −30 ° C. is 11.6 kgf · cm / cm and 5.8, respectively.
kgf · cm / cm, Rockwell hardness (scale R) measured by ASTM D785 at room temperature is 84.
Met.

[0080]Examples 2 and 3 and Comparative Example 1 Propylene-ethylene block copolymer (BPP2
4) Manufacturing After carrying out prepolymerization under the same conditions as in Example 1,
Amount of hydrogen gas (liter), second stage polymerization and third stage
Polymerization propylene and ethylene molar ratio, container pressure
(Kg / cm²・ G) and polymerization time (h) are shown in Table 1.
The main polymerization was carried out under the same conditions as in Example 1 except that
Propylene-ethylene block copolymer (BPP2
~ 4) was obtained. In addition, after completion of the second-stage polymerization and the third-stage polymerization
Table 1 shows the hydrogen content (mol%) in the unreacted gas of
It was

The MFR of the obtained propylene-ethylene block copolymer (BPP2-4) and the proportion of homopolypropylene portion, low ethylene concentration propylene-ethylene copolymerization portion and high ethylene concentration propylene-ethylene copolymerization portion, MFR of homopolypropylene part, △
H _m and ΔH _m ', [η] _L and ethylene content in the low ethylene concentration propylene-ethylene copolymerization portion, and [η] _H and ethylene content in the high ethylene concentration propylene-ethylene copolymerization portion. Table 2 shows the results of measurement performed in the same manner as in Example 1.

The tensile elongation at break, the flexural modulus, the Izod impact strength and the Rockwell hardness of BPPs 2 to 4 were measured in the same manner as in Example 1. The results are shown in Table 3.

Comparative Example 2 Propylene-ethylene block copolymer (BPP5)
Production After prepolymerization under the same conditions as in Example 1, the hydrogen gas amount (liter) in the first stage polymerization, the molar ratio of propylene and ethylene in the second stage polymerization, and the pressure in the vessel (kg / cm ² ·
G) and the polymerization time (h) are shown in Table 1, and main polymerization was carried out under the same conditions as in Example 1 except that the propylene-ethylene copolymerization part was one-stage polymerized, and the propylene-ethylene block copolymer was obtained. (BPP5) was obtained. The hydrogen content (mol%) in the unreacted gas after the completion of the second stage polymerization is shown in Table 1.

The MFR of the obtained propylene-ethylene block copolymer (BPP5) and the ratio of the homopolypropylene portion and the propylene-ethylene copolymer portion, and the MFR of the homopolypropylene portion, ΔH _m and ΔH _m '
And [η] _{H of} the propylene-ethylene copolymerized portion and the ethylene content were measured in the same manner as in Example 1 and Table 2
Shown in.

The tensile elongation at break, flexural modulus, Izod impact strength and Rockwell hardness of BPP5 were measured in the same manner as in Example 1. The results are shown in Table 3.

Comparative Example 3 Propylene-ethylene block copolymer (BPP6)
Production After prepolymerization under the same conditions as in Example 1, the hydrogen gas amount (liter) in the first stage polymerization, the molar ratio of propylene and ethylene in the second stage polymerization, and the pressure in the vessel (kg / cm ² ·
G) and the polymerization time (h) are shown in Table 1, and main polymerization was carried out under the same conditions as in Example 1 except that the propylene-ethylene copolymerization part was one-stage polymerized, and the propylene-ethylene block copolymer was obtained. (BPP6) was obtained. The hydrogen content (mol%) in the unreacted gas after the completion of the second stage polymerization is shown in Table 1.

The MFR of the obtained propylene-ethylene block copolymer (BPP6) and the proportion of the homopolypropylene portion and the propylene-ethylene copolymer portion, and the MFR of the homopolypropylene portion, ΔH _m and ΔH _m '
And [η] _{L of} the propylene-ethylene copolymerization portion and the ethylene content were measured in the same manner as in Example 1 and Table 2
Shown in.

Further, the tensile elongation at break, flexural modulus, Izod impact strength and Rockwell hardness of BPP6 were measured in the same manner as in Example 1. The results are shown in Table 3.

Comparative Example 4 Propylene-ethylene block copolymer (BPP7)
Production 65 parts by weight of the propylene-ethylene block copolymer (BPP5) obtained in Comparative Example 2 and 35 parts of the propylene-ethylene block copolymer (BPP6) obtained in Comparative Example 3
By mixing with parts by weight, a propylene-ethylene block copolymer (BPP7) was obtained. The tensile elongation at break, flexural modulus, Izod impact strength and Rockwell hardness of the obtained BPP7 were measured in the same manner as in Example 1. The results are shown in Table 3.

Table 1 Polymerization conditions BPP1 BPP2 BPP3 BPP4 BPP5 BPP6 First stage polymerization Hydrogen gas amount (liter) 10.5 8.7 16.5 9.0 12.0 8.8 Second stage polymerization C ₃ / C ₂ ⁽¹⁾ 1.91 1.97 1.91 1.91 0.46 1.59 Vessel pressure (kg / cm ² · G) 6.05 6.05 6.05 6.01 6.03 6.05 Polymerization time (h) 0.4 0.4 0.4 0.4 1.2 1.2 Hydrogen content (mol%) ⁽²⁾ 0.8 0.7 0.8 0.07 0.4 0.8 Third stage polymerization C ₃ / C ₂ 0.49 0.54 0.49 0.49 ─ ─ Container pressure (kg / cm ²・ G) 6.03 6.03 6.03 6.06 ─ ─ Polymerization time (h) 0.8 0.5 0.8 0.8 ─ ─ Hydrogen content (mol%) ⁽³⁾ 0.4 0.4 0.4 0.9 ─ ─ Note (1) Molar ratio of propylene and ethylene. (2) Hydrogen content in the unreacted gas after the completion of the second stage polymerization. (3) Hydrogen content in the unreacted gas after the completion of the third stage polymerization.

Table 2 Properties of BPP BPP1 BPP2 BPP3 BPP4 BPP5 BPP6 Homopolypropylene portion Content (wt%) 82 88 82 82 82 82 MFR _H (g / 10min) 130 85 300 105 160 90 Heat of fusion (cal / g) measurement Value (△ H _m ) 28.1 27.8 28.8 28.0 28.4 27.9 Calculated value (△ H _m ') 27.8 27.6 28.4 27.7 28.0 27.6 Copolymerized portion ⁽¹⁾ _CL (% by weight) ⁽²⁾ 6 5 6 6 ─ 18 _GL ( ⁽ % By weight) ⁽³⁾ 35 35 35 35 ─ 35 [η] _L (dl / g) 3 3 3 6 ─ 3 _CH (% by weight) ⁽⁴⁾ 12 7 12 12 18 ─ _GH (% by weight) ^{(5 )} 65 65 65 65 65 ─ ［η］ _H (dl / g) 5 5 5 25 ─ MFR _BPP (g / 10min) 28 33 55 30 29 30 Note (1) Ethylene-propylene copolymer part. (2) It is the content of propylene-ethylene copolymerized portion of low ethylene concentration when the total content of propylene-ethylene copolymerized portion and crystalline homopolypropylene portion is 100% by weight. Refers to the proportion of parts (3) The ethylene content of the propylene-ethylene copolymerization portion having a low ethylene concentration. (4) It is the content of propylene-ethylene copolymerized portion with high ethylene concentration when the total content of propylene-ethylene copolymerized portion and crystalline homopolypropylene portion is 100% by weight, and it is soluble in cold xylene. Refers to the proportion of parts. (5) The ethylene content of the propylene-ethylene copolymerization portion having a high ethylene concentration.

Table 3 Example 1 Example 2 Example 3 BPP type BPP1 BPP2 BPP3 BPP characteristics Tensile elongation at break (%) 90 80 75 Flexural modulus (kg / cm ² ) 12600 16600 13000 Izod impact strength ^{(1 )} 23 ℃ 11.6 8.8 11.2 -30 ℃ 5.8 4.7 5.7 Rockwell hardness (R) 84 95 86 Note (1) Unit: kgf ・ cm / cm

Table 3 (continued) Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 BPP type BPP4 BPP5 BPP6 BPP7 BPP characteristics Tensile elongation at break (%) 95 35 150 100 Flexural modulus (kg / cm ² ) 12100 12700 12200 12500 Izod impact strength 23 ℃ 11.2 8.9 11.1 9.5 -30 ℃ 4.2 4.1 3.9 3.9 Rockwell hardness (R) 81 85 80 83

As is apparent from Tables 2 and 3, Example 1
~ 3 propylene-ethylene block copolymer is MFR
And high moldability, and also excellent in impact resistance, rigidity, hardness and the like. From the comparison of Examples 1 to 3 and Comparative Example 1, the intrinsic viscosity [η] _L of the propylene-ethylene copolymerization portion having a low ethylene concentration is higher than the intrinsic viscosity [η] _H of the propylene-ethylene copolymerization portion having a high ethylene concentration. It can be seen that the impact resistance and the flexural modulus at low temperature decrease as the value increases. From the comparison of Examples 1 to 3 and Comparative Examples 2 and 3, when the propylene-ethylene block copolymer produced by the one-step polymerization of the propylene-ethylene copolymer portion is used, the impact resistance at low temperature is lowered. I understand.
As is clear from Examples 1 to 3 and Comparative Example 4, a propylene-ethylene block copolymer containing a low-ethylene concentration propylene-ethylene copolymer portion and a high-ethylene concentration propylene-ethylene copolymer portion are contained. Even if a propylene-ethylene block copolymer is blended,
Sufficient impact resistance cannot be obtained.

[0095]

The propylene-ethylene block copolymer of the present invention comprises a homopolypropylene portion having a constant relationship between the heat of fusion and the melt flow rate, a propylene-ethylene copolymer portion having a low ethylene concentration and a high ethylene content. Since the propylene-ethylene copolymerized portion having an ethylene concentration is produced by multistage polymerization, it is excellent in impact resistance, rigidity and moldability.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satoshi Shimizu 4-1-1 Tsukiji, Chuo-ku, Tokyo Tonen Kagaku Co., Ltd. (72) Inventor Masashi Nakajima 4-1-1 1-1 Tsukiji, Chuo-ku, Tokyo Tonen Kagaku Within the corporation (56) Reference JP-A-58-40314 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08F 293/00

Claims (3)

(57) [Claims] 1. Propylene obtained by multistage polymerization
An ethylene block copolymer (a) having a melt flow rate (MFR) measured according to ASTM D-1238 in the range of 1 to 1000 g / 10 min, and having a heat of fusion (ΔH _m ) And MFR are 60 to 96% by weight of a homopolypropylene portion satisfying the relational expression ΔH _m ≧ 24.50 + 1.583logMFR, and (b) a propylene-ethylene copolymerized portion having a low ethylene concentration (ethylene content of 35 to 45 %). Intrinsic viscosity is 2-5% by weight
dl / g. 2 to 38% by weight, and (c) a high ethylene concentration propylene-ethylene copolymerization portion (ethylene content is 50 to 90% by weight, intrinsic viscosity is 3 to 6).
dl / g. ) 2 to 38% by weight, a propylene-ethylene block copolymer. 2. Propylene-ethylene according to claim 1.
In the block copolymer, the low ethylene concentration
Intrinsic viscosity of the pyrene-ethylene copolymer part is 3-5 dl / g
Propylene-ethylene block characterized by
Copolymer. In ethylene block copolymer, propylene said high ethylene concentration - - 3. The propylene according to claim 1 or 2 intrinsic viscosity ethylene copolymer portion, the low concentration of ethylene propylene - ethylene copolymer portion A propylene-ethylene block copolymer characterized by having a viscosity higher than the intrinsic viscosity.