JPH01263139A - Polypropylene resin composition - Google Patents

Abstract

PURPOSE:To obtain crystalline polypropylene resin composition, containing a polymer prepared by anionic polymerization of cyclohexyl methacrylate and capable of providing molded products excellent in physical properties. CONSTITUTION:A crystalline polypropylene resin composition containing (A) crystalline polypropylene, e.g., random or block copolymer, prepared by polymerizing propylene with <=50wt.% other olefins in the presence of a catalyst system consisting of titanium trichloride (modified substance) obtained by reducing titanium tetrachloride with metallic aluminum, hydrogen, etc., an organoaluminum compound and a stereoregularity improver (e.g., ether or ester) and (B) >=0.01wt.ppm, preferably 0.1-1000wt.ppm polymer, prepared by anionic polymerization of cyclohexyl methacrylate and having 1000-10000000 number- average molecular weight.

Description

DETAILED DESCRIPTION OF THE INVENTION [Graduation Field of Application] The present invention relates to a crystalline polypropylene resin composition containing a specific compound.

[Conventional technology]

Although polypropylene is a polymer with excellent rigidity, there is a problem in that the degree of crystallinity of molded products is relatively low, and the physical properties of ordinary molded products are inferior to the originally expected physical properties. To solve this problem, a method of adding various nucleating agents is usually used, and a molded product with excellent rigidity or transparency is obtained.

[Problems to be solved by the invention]

The method of adding a nucleating agent is simple and effective, but it requires the addition of a relatively large amount of nucleating agents, which may cause variations in the physical properties of the molded product due to poor dispersion of the nucleating agent, or bleeding of the added nucleating agent. There was a problem. For this purpose, it is known to add a specific polymer compound, but a more effective compound is desired.

[Means for solving problems]

The present inventors have diligently searched for more effective compounds and have arrived at the present invention.

That is, the present invention is a crystalline polypropylene resin composition containing a polymer obtained by anionically polymerizing cyclohexyl methacrylate.

The cyclohexyl methacrylate polymer used in the present invention can be produced using various anionic polymerization catalysts, but a polymer obtained by polymerizing with a Grignard reagent at a relatively low temperature is preferably used, and the polymerization method is as follows: A known method is preferably adopted as a method for producing an isotactic polymer of methyl methacrylate (for example, P
Olmer Journal, Vol, 1797? -9
80 (1985), Polymer Letters V
ol, 9129-13H1971)). There is no particular restriction on the molecular weight of the cyclohexyl methacrylate polymer, but the number average molecular weight is usually 1000 or more and 100
It is common to use a value of 0,000 or less.

In the present invention, the crystalline polypropylene used includes not only a homopolymer of propylene but also a random or block copolymer with other olefins such as ethylene. % by weight or less. There are no particular restrictions on the method for producing these propylene polymers, and catalysts usually composed of a transition metal catalyst and an organoaluminum compound can be used.

Examples of catalysts consisting of a transition metal catalyst and an organoaluminum compound include various known catalyst systems that provide polypropylene with high stereoregularity.Titanium halides are preferably used as transition metal catalysts.For example, titanium tetrachloride is combined with metallic aluminum. , a catalyst system consisting of titanium trichloride obtained by reduction with hydrogen or organoaluminium, or a modified version thereof with an electron-donating compound, an organoaluminum compound, and, if necessary, a stereoregular agent such as an oxygen-containing organic compound; Alternatively, an M+i metal catalyst obtained by supporting titanium halide on a carrier such as magnesium halide or a carrier treated with an electron-donating compound, an organoaluminum compound, and if necessary a stereoregularity improver such as an oxygen-containing organic compound. The following catalyst system is exemplified. (For example, various examples are described in the following documents. Ziegler
-Natta Catalysts and Poly
Merization by John Boor J
r(Academic Press)+Journal
of Macrorecular Science
-Reviews in Macromolecules
r Cbemistry and Physics C
24, (3) 355-385 <1984), same C25 (
1) 578-97 (198 Here, as the stereoregularity improver or the electron-donating compound, oxygen-containing compounds such as ethers, esters, orthoesters, and alkoxy silicon compounds can be exemplified preferably, and as the electron-donating compounds, further Alcohol, aldehyde, water, etc. can also be used.

As the organoaluminum compound, triple kyl aluminum, dialkyl aluminum halide, alkyl aluminum sesquihalide, alkyl/L/fluminium dihalide can be used, and the alkyl group is a methyl group,
Examples include ethyl group, propyl group, butyl group, hexyl group, etc., and examples of halides include chlorine, bromine, and iodine.

Preferred titanium halides include those obtained by modifying titanium tetrachloride with aluminum or organic aluminum with ether or ester, or those obtained by co-pulverizing magnesium chloride and an organic compound with titanium tetrachloride. Alternatively, the reaction product of magnesium chloride and alcohol is dissolved in a hydrocarbon solvent, and then treated with a precipitant such as titanium tetrachloride to make it insoluble in the hydrocarbon solvent, and if necessary, an electron-donating compound such as an ester or ether is added. It is a supported titanium oxide obtained by a method of treating with titanium and titanium tetrachloride.

In the present invention, the polymerization of propylene can be carried out in an inert medium such as pentane, hexane, heptane, octane, benzene, toluene, etc., or by a bulk polymerization method using propylene itself as a liquid medium, or by a method in which there is substantially no liquid medium. It can also be carried out by a gas phase polymerization method, and there are no particular limitations on the method, and various known methods and conditions can be employed. For example, the polymerization temperature is generally from normal temperature to 100° C., and the polymerization pressure is generally from normal pressure to 50 kg/cmz gauge.

In the present invention, the quantitative ratio of the polymer obtained by polymerizing cyclohexyl methacrylate by anionic polymerization to polypropylene is such that the polymer of cyclohexyl methacrylate has an O,OLwtppm or more, and preferably 0.1
It is about wLppm to 1000w100O.

If the amount is less than 0.01 wtppm, there is no effect of improving the physical properties, and if it is more than 10.00 wtppm, it is not particularly effective.

〔Example〕

The present invention will be further explained by referring to the following examples.

Example 1 A vibratory mill equipped with four grinding pots each having an internal volume of 41 and containing 9 kg of steel balls each having a diameter of 121 was prepared. Add 300 g of magnesium chloride, 60 ml of tetraethoxysilane, 4 ml of α, α, α-trichlorotoluene to each bottle under nitrogen atmosphere.
5ml was added and pulverized for 40 hours. 300 g of the co-pulverized material obtained in this way was put into a 51 flask, and 1.51 g of titanium tetrachloride was added.
, 1.51% of toluene was added, stirred at 100°C for 30 minutes, the supernatant was removed, and 1.51% of titanium tetrachloride was added,
1.51 g of toluene was added and stirred at 100° C. for 30 minutes, then the supernatant was removed and the solid content was repeatedly washed with n-hexane to obtain a transition metal catalyst slurry. When we sampled a portion and analyzed the titanium content, it was found to be 1.9%.

Inner volume 200 ml flask under nitrogen atmosphere 40 ml of toluene, 20 mg of the above transition metal catalyst, 0.12 hl of diethylaluminium chloride, 0.06 ml of methyl p-toluate, 0.12 m of triethyl aluminum
1 was added to prepare a catalyst slurry. This catalyst slurry was placed in an autoclave with an internal volume of 51 kg, and 1.8 kg of propylene was added.
, 3°3N+ of hydrogen was added, and a polymerization reaction was carried out at 75°C for 2 hours.

After the polymerization reaction, unreacted propylene was purged and the polymer was taken out and dried at 80° C. at 60 mml (g) for 12 hours.

380 g of powder was obtained, and the intrinsic viscosity (hereinafter abbreviated as η) measured with a tetralin solution at 135 ° C and the extraction residual rate (hereinafter abbreviated as U, Powder weight after extraction/powder weight before extraction (expressed as a 100% ratio) was measured.

Using ethylmagnesium chloride as a catalyst, polymerization was carried out at -78°C for 12 hours in a toluene solvent at a catalyst concentration of 0.1 mol/1 and a monomer concentration of 2 mo+/1 to obtain polycyclohexyl methacrylate (change rate 92χ, toluene solvent The intrinsic viscosity at 30°C was 0.18. Polypropylene powder was mixed with polycyclohexyl methacrylate obtained in the above reaction at a weight ratio of 10/10,000, a phenolic stabilizer at a weight ratio of 10/10,000, and calcium stearate at a weight ratio of 15/10,000. In addition, the melt flow index was measured, and an injection sheet with a thickness of 11 mm was prepared, and the bending rigidity was measured.

Melt 7u-index (Ml) AST
M 01238 (230℃) Bending rigidity A
STM 0747-63 (20° C.) Using a differential thermal analyzer, the melting point and crystal temperature were measured as the maximum peak temperature by raising or lowering the temperature by lOo (/win). The results are shown in the table.

Comparative Example 1 Example 1 was repeated except that syndiotactic polycyclohexyl methacrylate was not used. The results are shown in the table.

Example 2 Commercially available highly active titanium trichloride (Toho Titanium TACS)
-21) was used as a transition metal catalyst. Titanium trichloride catalyst 100mg, diethylaluminum chloride 1.
0 ml in toluene, then the slurry was placed in an autoclave with an internal volume of 51, and 1.8 kg of propylene was added.
, 4.4 NI of hydrogen were added, and polymerization was carried out at 75°C for 4 hours to obtain 920 g of polypropylene. This propylene was treated at 100''C for 1 hour in the presence of propylene oxide lhl, and then the polypropylene powder was taken out.

Evaluation was carried out in the same manner as in Example 1, except that this polypropylene was used and 30 wtppm of polycyclohexyl methacrylate obtained in Example 1 was used.

Comparative Example 2 Using polycyclohexyl methacrylate (1) The same procedure as in Example 2 was performed except for the strength and strength. The results are shown in the table.

〔effect〕

The composition of the present invention has extremely excellent physical properties and is of industrial value.

Claims (1)

[Claims] (1) A crystalline polypropylene resin composition containing a polymer obtained by anionically polymerizing cyclohexyl methacrylate.