JPS63291907A - Polypropylene - Google Patents

Abstract

PURPOSE:To obtain polypropylene having excellent orientation properties, rigidity, transparency, antistatic properties and blocking resistance, by subjecting propylene and a small amount of ethylene to random copolymerization with a stereoregular catalyst. CONSTITUTION:Propylene and a small amount of ethylene are subjected to random copolymerization with a stereoregular polymerization catalyst to give a polypropylene having 0.1-1.5wt.%, especially 0.3-1.4wt.% ethylene and <=0.6wt.% extract content with boiling normal butanol. For example, a combination of (A) a solid Ti catalytic component comprising Mg, Ti, a halogen and an electron donor (e.g. ethyl acetate or methyl acrylate) as essential components and (B) an organoaluminum compound (e.g. triethylaluminum) is preferable as the polymerization catalyst.

Description

DETAILED DESCRIPTION OF THE INVENTION [Background of the Invention] Technical Field The present invention relates to polypropylene having excellent stretchability, rigidity, transparency, antistatic properties, and anti-blocking properties.

Conventional polypropylene has excellent rigidity, and its stretched products have O
It is widely used as PP film, stretched tape, flat yarn, blown film, etc.

Polypropylene includes a homopolymer made of a propylene homopolymer and a random copolymer made by copolymerizing a small amount of ethylene.

Since homopolymers have excellent rigidity, homopolymers are usually used for applications that require rigidity, but homopolymers have poor antistatic properties, stretchability, and the like.

On the other hand, JP-A-56-32512, JP-A-59-135209 and JP-A-59-149 indicate that stretchability can be improved by random copolymerization of ethylene.
It is proposed in each publication No. 909. Although antistatic properties can be improved by copolymerizing ethylene, blocking resistance in stretched films and opening properties in blown films deteriorate.

A method of reducing cold xylene solubles as a method for improving blocking resistance (JP-A No. 51-24685, No. 53-
No. 7786 and No. 54-118486), but the correspondence between blocking resistance and cold xylene soluble content does not necessarily hold within the range of a small amount of ethylene content that exhibits the same stiffness as a homopolymer. Therefore, polypropylene with excellent blocking resistance and antistatic properties has not yet been developed.

[Summary of the invention]

Summary The present inventors conducted studies aimed at developing polypropylene with excellent blocking resistance and antistatic properties, and as a result, they arrived at the present invention.

That is, the polypropylene according to the present invention is obtained by random copolymerization of propylene and a small amount of ethylene using a stereoregular polymerization catalyst, and has an ethylene content a of 0.1 to 1.
5% by weight and boiling normal butanol extractable content is 0.
．． It is characterized by being 6% by weight or less.

Effects The polypropylene or film thereof according to the present invention has excellent stretchability, rigidity, transparency, antistatic property, and blocking resistance.

(Detailed Description of the Invention) Polypropylene The polypropylene according to the present invention is obtained by randomly copolymerizing propylene and a small amount of ethylene using a stereoregular catalyst, and the ethylene content (the ethylene content is defined as It goes without saying that the content of ethylene is 0.1 to 1.5% by weight, preferably 0.
．． 2 to 1.5% by weight, particularly preferably 0.3 to 1.4% by weight. Ethylene content is 0.1WHk
If it is less than 1.5% by weight, the antistatic properties will not be improved.
Anything exceeding this will lack rigidity. The ethylene content in the present invention is determined by the C1C13-N spectrum (F
This is a value measured by X-200).

The polypropylene according to the invention also has a boiling normal-butanol extractable content of 0. 6ii% by weight or less, preferably 0.5% by weight or less, particularly preferably 0.4% by weight or less. Boiling normal butanol extract content is 0
．． If it exceeds 7% by weight, blocking resistance will not be improved. The boiling normal butanol extract in the present invention is obtained by dissolving 10 g of the polymer in 4 liters of xylene, then gradually cooling it to 23°C, leaving it in a bath at 23°C overnight, filtering it, concentrating the ψ liquid, solidifying it, and drying it. The obtained cold xylene soluble portion (1 g) was extracted with 400 ml of n-butanol using a Soxhlet extractor for 4 hours, and after extraction, the n-butanol was concentrated, dried, and weighed.

The polypropylene according to the invention has a melt flow rate (
MFR) (according to ASTM-1238) is 0.1 to 10
It is usually about 0, preferably about 0.2 to 50. In addition, boiling normal heptane insoluble matter is 95
The amount of tIF is usually at least 96% by weight, preferably at least 96% by weight.

Since the polypropylene according to the present invention is obtained by random copolymerization of propylene and a small amount of ethylene using a stereoregular polymerization catalyst, its molecular structure consists of one unit of 10H2-CH(CH3) and one unit of -CH2-CH2.
It is understood that one unit is randomly arranged.

Additives used in polyolefins, such as various antioxidants, stabilizers, antiblocking agents, antistatic agents, processing aids, and colorants, can be used in the polypropylene of the present invention.

Production of Polypropylene The polypropylene according to the present invention is obtained by random copolymerization of propylene and a small amount of ethylene using a propylene stereoregular catalyst, as described above.

Polymerization of propylene using a stereoregular polymerization catalyst is well known, and the polypropylene of the present invention may be copolymerized by adding a small amount of ethylene almost evenly to propylene during such propylene polymerization.

Examples of stereoregular polymerization catalysts for propylene include:
There are some combinations of (A) and (B) below.

(A) A solid titanium catalyst component containing magnesium, titanium, and an IXX rosin electron donor as essential components.

(B) Organoaluminum compound component (A) A preferred solid titanium catalyst component (A) contains magnesium, titanium, halogen, and an electron donor as essential components. Here, "making it an essential component" means not only that the solid titanium catalyst component (A) consists only of these three specific components, but also that it at least maintains the effect of the combination of these three components or This means that additional ingredients may be included so long as they do not unduly detract. Such additional components are, for example, phenohalogenated silicon compounds.

Magnesium is usually introduced into component (A) by means of magnesium halides, titanium by means of titanium halides, and /XXrosin by means of these compounds.

(1) Magnesium halide The magnesium halide is preferably magnesium dihalide, and magnesium chloride, magnesium bromide, and magnesium iodide can be used. More preferably it is magnesium chloride, more preferably substantially anhydrous.

In addition, magnesium halides include magnesium oxide,
Magnesium hydroxide, hydrotalcite, magnesium carboxylate, alkoxymagnesium, allyloxymagnesium, alkoxymagnesium halide, allyloxymagnesium halide, organomagnesium compound as an electron donor, halosilane, alkoxysilane, silanol, AI compound, halogenated It may also be magnesium chloride obtained by treatment with a titanium compound, titanium tetraalkoxide, or the like.

(2) Titanium halide Typical titanium halides are trivalent and tetravalent titanium halogen compounds. Preferred titanium halogenated compounds are tetravalent halogenated titanium compounds of nm011 or 2 among compounds represented by the general formula 7 (% hydrogen hydride residue, X is halogen). Specifically, TlC14, Ti (OBu
) C13, T i (OB u ) 2 CI 2, etc., but particularly preferred is TiC
1 and T i (OB u) Cl 3 and other tetrahalogenated titanium and monoalkoxytrihalogenated titanium compounds.

(3) Electron Donor As the electron donor which is an essential component of this preferred solid catalyst component (A), aliphatic carboxylic acid esters, aromatic carboxylic acid esters, acid halides, etc. can be used.

Specifically, ethyl acetate, methyl acrylate, methyl benzoate, ethyl benzoate, methyl toluate, ethyl toluate, diethyl orthophthalate, di-n-butyl orthophthalate, di-n-heptyl orthophthalate,
Examples include di-n-butyl metaphthalate, methyl cellosolve acetate, cellosolve acetate, acetic chloride, orthophthalic acid dichloride, metaphthalic acid dichloride, balaphthalic acid dichloride, and the like.

Component (B) The organoaluminum compound used as component (B) has the general formula AlRnX3-n (where R has 1 to 1 carbon atoms)
12 hydrocarbon residues, X is a halogen or alkoxy group, and n represents Own≦3) is preferred.

Such organoaluminum compounds are specifically, for example, triethylaluminum, tri-n-propylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-lowhexylaluminum, triisohexylaluminum, trioctylaluminum, diethylaluminium. hydride, diisobutylaluminum hydride, diethylaluminum monochloride, ethylaluminum sesquichloride, diethylaluminum monoethoxide, and the like. Of course, these organic aluminum compounds are 2F! The above can also be used together.

Optionally, a third component can be added during the polymerization.

Examples of the third component include aromatic monocarboxylic acid esters, organosilicon compounds, amines, acetals, ketals, and the like.

Specifically, methyl benzoate, ethyl benzoate, methyl toluate, ethyl toluate, diphenyldimethoxysilane, phenyltrimethoxysilane, methyltert-butyldimethoxysilane, 2, 2.4.4-tetramethylpiperidine, diphenyl. Examples include dimethoxymethane and diphenylmethoxymethane. These third components are 2
It is also possible to use more than one species in combination.

Polymerization Polymerization can be carried out in either liquid phase or gas phase. When liquid phase polymerization is carried out, either a method using an inert solvent such as hexane or heptane as the reaction medium or a method using propylene itself as the reaction medium may be used. The amount of catalyst used is A per 1 liter of reaction volume.
The component is 0.0001 to 1.0 mmol in terms of titanium atoms, and the amount of component (B) is 1 to 2000 mol, preferably 5 to 500 mol, per 1 mol of titanium atom in component (A). do. Catalyst components (A) and (B) may be brought into contact during polymerization or may be brought into contact before polymerization.

The catalyst components (A) and (B) may be contacted before polymerization under an inert gas atmosphere or under an olefin atmosphere such as propylene.

The method of supplying propylene and ethylene may be a method of supplying a mixed gas or a method of quantitatively supplying ethylene under a constant pressure of propylene.

The polymerization temperature is preferably 10°C to 100°C, particularly preferably 40°C to 90°C. Pressure is normal pressure ~ 50kg
/cj, preferably 2 to 50 kg/cj.

Polymerization is preferably carried out continuously. Also, MFH
can be advantageously adjusted with hydrogen.

EXPERIMENTAL EXAMPLES The following examples and comparative examples are intended to explain the present invention more clearly, and the present invention is not limited only by these examples.

Note that the characteristic values in the following examples were measured by the following method.

MFR was measured in accordance with ASTM-I238. Transparency was measured by stacking four films in accordance with ASTM D-1003. The blocking property was measured by stacking two films so that the contact area was 10 cm, placing them between two glass plates, and applying a load of 50 H/c-.
After being left in an atmosphere at 0° C. for 7 days, it was peeled off at a tensile speed of 500 μm/min using a Schopper type tester, and the maximum load was read and evaluated. Antistatic properties were measured using a static honest meter made by Anato Shokin at a temperature of 23°C.
The corona discharge treated surface was measured in a room with 50% humidity to read the half-life.

Examples 1 and 2 1) Production of titanium-containing solid component 50 ml of dehydrated and deoxygenated n-hebutane was introduced into a 390 ml flask that had been sufficiently purged with nitrogen, and then Mg
C12 (magnesium chloride) 0.1 mol, T1 (OB
u) After introducing 0.2 mol of 4-butoxytitanium), 9
A hydrocarbon solution of MgCl2 was prepared by reacting at 0°C for 2 hours. Next, 12 ml of methylhydrodiene polysiloxane (20 cps) was added and reacted at 40° C. for 3 hours, resulting in the precipitation of about 40 g of off-white titanium-magnesium precipitated solid. When this titanium magnesium precipitated solid was thoroughly washed and analyzed, it was found that this precipitated solid had 1
It contained 2.1% by weight of MgCl2.

From this titanium-magnesium precipitated solid, 20 g (M g
C12-2, 42g) was sampled and silicon tetrachloride7. 0 ml (0.06 mol) of n-hebutane 2
After diluting it to 5ml and adding it dropwise at room temperature for 1 hour,
The reaction was carried out at ℃ for 2 hours. After the reaction is complete, n-hebutane 2
00ml twice, and the reaction was repeated twice with 20ml of TiCl4 (titanium tetrachloride) at 90°C for 2 hours.

Then, 0.10 g of cellosolve acetate (cellosolve acetate/M
25 m of n-hebutane solution containing g-0,025 molar ratio)
1 was added dropwise at 50°C over 30 minutes, and the mixture was reacted at 80°C for 3 hours. After the reaction was completed, the product was washed with n-hebutane until soluble titanium was no longer observed to obtain the desired titanium-containing solid component slurry. When a portion of this slurry was taken out and analyzed, it was found that the solid contained 4.51 ffi amount of titanium.

2) After sufficiently purging a stirred autoclave with a polymerization internal volume of 200 liters with propylene, 70 liters of dehydrated and deoxidized normal heptane was introduced, and triethylaluminum (B
) 35.0 g, diphenyldimethoxysilane 11.3.
Then, 2.0 g of the solid composition (A) was introduced at 70° C. under a propylene atmosphere. After heating the autoclave to 75℃, ethylene-propylene mixed gas was introduced and the hydrogen concentration was maintained at 0.25% at a rate of 7 kg/cj.
The pressure was increased to G, and polymerization was further carried out at 7 kg/cjG for 3 hours.

After the polymerization was completed, the slurry containing the produced polymer was filtered to obtain a white powder polymer.

Next, 100 parts by weight of the copolymer was added with 2.0% antioxidant.
0.10 parts by weight of 6-di-t-butyl-p-cresol,
105 parts by weight of Irganox 1010 JO, 0.05 m part of calcium stearate as a hydrochloric acid scavenger, 0.10 part by weight of silicon dioxide as an anti-blocking agent, and 0.0 m part of stearyl monoglyceride as an antistatic agent.
50 parts by weight and 0.10 parts by weight of an ethylene oxide adduct of alkylamine were added, mixed, and pelletized.

This pellet is made into a sheet-like film using an extruder,
Stretched 5 times in the vertical direction and 10 times in the horizontal direction, finally reaching a thickness of 3
A stretched film of 0 μm was obtained. One side of the stretched film was subjected to corona discharge treatment.

The results obtained were as shown in Table 1.

Example 3 1) Production of titanium-containing solid component 100 ml of dehydrated and deoxygenated normal hemobutane was introduced into a flask that had been sufficiently purged with nitrogen, and then MgCl2
0.1 mol and 0.2 mol of Ti(0-nC4H9)4 were introduced,
The reaction was carried out at 95°C for 2 hours. After the reaction was completed, the temperature was lowered to 40° C., and then 15 m) of methylhydrodiene polysiloxane was introduced and reacted for 3 hours. After the reaction is complete,
The generated solid component was washed with n-heptane, a part of it was taken out, and the composition was analyzed, and it was found that Ti-15,
2% by weight, Mg-4, 2% by weight.

Next, 100 ml of dehydrated and deoxygenated normal hemobutane was introduced into a flask that had been sufficiently purged with nitrogen, and 0.03 mol of the component synthesized above was introduced in terms of Mg atoms. 5i
9 by introducing 0.05 mol of C in 15 minutes at 30°C.
The reaction was carried out at 0°C for 2 hours.

After the reaction was completed, it was washed with purified normal heptane. Then, ortho-CH (COC
i) 20,004 mol were mixed and introduced at 70°C for 30 minutes and reacted at 90°C for 1 hour. After the reaction was completed, the purified normal butante was washed. Then TiC14
1 ml (Ti/Mg-0.31 (molar ratio)) was introduced and reacted at 100°C for 6 hours. After the reaction was completed, it was washed with normal heptane to obtain a catalyst component.

The T1 content was 3.05% by weight.

2) Polymerization The polymerization method and molding method were the same as in Examples-1 and 2.

The results obtained were as shown in Table 1.

Example 4 1) Production of titanium-containing solid component 100 ml of dehydrated and deoxygenated normal hemobutane was introduced into a flask that had been purged with nitrogen, and then MgCl2
0.1 mol of Ti(On Bu) 4, 0.195 mol of Ti(On Bu)4, and then 0.007 mol of n-C4H90H were introduced, and the mixture was heated to 90°C.
The reaction was carried out for 2 hours. After the reaction was completed, the temperature was lowered to 40°C, and then methylhydrodiene polysiloxane (20°C
Centistokes) was introduced in an amount of 15 ml and allowed to react for 3 hours. The generated solid component was washed with n-heptane, a portion was taken out, and a composition analysis revealed that Ti
-14.2% by weight and Mg -4.3% by weight.

Next, 501 Ells of dehydrated and deoxygenated normal hebutane was introduced into a flask that had been sufficiently purged with nitrogen, and 0.03 mol of the component synthesized above was introduced in terms of Mg atoms. 50 ml of normal heptane and 0.5 mol of S I C were mixed and introduced at 30° C. for 15 minutes, and the mixture was heated to 50° C. and reacted for 1 hour. After the reaction was completed, it was washed twice with 1 liter of normal hebutane. Then, S I C1
A mixture of 40,025 mol and 25 ml of normal hemobutane was introduced at 30° C. over 15 minutes, and reacted for 30 minutes. Next, 0.0015 mol of dihebutyl phthalate was introduced, and the mixture was reacted at 50° C. for 1 hour. After the reaction was completed, it was washed twice with 1 liter of normal heptane. Then, T i
25 ml of C1 was introduced and the reaction was carried out at 90°C for 1 hour. After the reaction was completed, it was thoroughly washed with normal hemobutane and used as a catalyst component. A portion of it was taken out and analyzed for composition, and the T1 content was -2.52% by weight.

2) Polymerization The polymerization method and molding method were the same as in Examples-1 and 2.

The results obtained were as shown in Table 1.

Comparative Example-1 Example-3 except that the ethylene-propylene mixed gas supplied during polymerization was changed to only propylene in Example-3.
Same as 3.

The results were as shown in Table 1.

Comparative Examples 2 and 3 After a stirred autoclave with an internal volume of 200 liters was sufficiently replaced with propylene, 70 liters of dehydrated and deoxygenated normal heptane was introduced, and 40.0 liters of diethyl aluminum chloride was added. and titanium trichloride (TAC-132 manufactured by Toho Titanium Co., Ltd.) 20, or, were introduced at 65° C. under a propylene atmosphere. After heating the autoclave to 70'C, ethylene-propylene mixed gas was introduced and the pressure was increased to 7 kg/cd G while keeping the hydrogen concentration at 2.0%, and polymerization was further performed at 7 kg/cd G for 5 hours. .

The treatment and molding method after completion of polymerization are the same as in Examples 1 and 2.

The results were as shown in the m1 table.

Comparative Example 4 Comparative Examples 2 and 3 were the same as Comparative Examples 2 and 3, except that the ethylene-propylene mixed gas supplied during polymerization was changed to only propylene.

The results were as shown in Table 1.

Claims (1)

[Claims] It is obtained by random copolymerization of propylene and a small amount of ethylene using a stereoregular polymerization catalyst, and has an ethylene content of 0.1 to 1.5% by weight and a boiling normal butanol extractable content of 0.6% by weight or less. Polypropylene is characterized by: