JPH01234482A - Bonding polypropylene resin composition - Google Patents

Abstract

PURPOSE:To obtain the subject industrially extremely valuable composition excellent in adhesive strength, by mixing PP having a silane compound in the backbone chain with polybutadiene having a specific structure. CONSTITUTION:The objective composition obtained by thermally mixing a crystalline propylene copolymer prepared by polymerizing an alkenylsilane and/or alkenylchlorosilane and propylene using a stereoregulne catalyst with polybutadiene having OH groups. Furthermore, the polymerization ratio of the alkenylsilane and propylene is preferably 30-0.01mol% alkenylsilane.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a polypropylene resin composition for adhesive use. Specifically, the present invention relates to an adhesive resin composition obtained by mixing polypropylene containing a silane compound in its main chain and polybutadiene having a specific structure.

[Conventional technology]

In order to take advantage of the properties of polyolefins and further impart properties not originally possessed by polyolefins, such as gas barrier properties, it is widely practiced to form multilayer structures with other polymers, especially those containing polar groups.

Originally, polyolefins and polar group-containing polymers are not compatible, so they cannot be bonded simply by pasting them together, but instead an adhesive resin is sandwiched between them.For this purpose, maleic anhydride was grafted onto polyolefins. Polymers are used.

[Problem to be solved by the invention]

A polymer obtained by grafting maleic anhydride onto a polyolefin has a certain effect on improving the adhesion between a polyolefin and a polar group-containing polymer, but it is particularly effective for adhesion between an ethylene-vinyl alcohol copolymer (hereinafter referred to as EVAL) and polypropylene. However, the development of adhesive resin compositions with improved adhesive properties has been desired.

[Means to solve the problem]

The present inventors have diligently searched for a highly crystalline polypropylene resin composition that achieves the above-mentioned problems, and have completed the present invention.

That is, the present invention provides an adhesive product prepared by heating and mixing a crystalline propylene copolymer obtained by polymerizing alkenylsilane and/or alkenylchlorosilane and propylene using a stereoregular catalyst, and polybutadiene containing an OH group. It is a polypropylene resin composition.

The crystalline propylene copolymer used in the present invention obtained by polymerizing alkenylsilane and/or alkenylchlorosilane (hereinafter simply referred to as alkenylsilane) and propylene using a stereoregular catalyst is, for example, US Pat. It can be produced by the method disclosed in No. 223.686.

The alkenylsilane used herein is one having at least one 5i-H bond, for example,
Vinylsilane, allylsilane, butenylsilane, pentenylsilane, 1 to 5i-quadruple bonds of these monomers
Examples include compounds in which two groups are substituted with alkyl groups. Further, the alkenylchlorosilane is one in which part or all of 5i-H of the above alkenylsilane is substituted with chlorine.

Many catalysts with improved performance have since been disclosed as stereoregular catalysts, and these can be used.

Further, as a polymerization method, in addition to a solvent method using an inert solvent, a bulk polymerization method and a gas phase polymerization method can also be employed.

Preferable examples of stereoregular catalysts include catalyst systems consisting of transition metal catalysts and organometallic compounds, and titanium halides are preferably used as transition metal catalysts. For example, titanium tetrachloride is combined with metal aluminum, hydrogen, or organic aluminum. A catalyst system consisting of titanium trichloride obtained by reduction with or modified with an electron-donating compound, an organoaluminum compound and, if necessary, a stereoregularity improver such as an oxygen-containing organic compound, or a magnesium halide. A catalyst system consisting of a transition metal catalyst obtained by supporting a titanium halide on a carrier such as or a carrier treated with an electron-donating compound, an organoaluminium compound, and, if necessary, a stereoregularity improver such as an oxygen-containing organic compound, is used. (For example, various examples are described in the following documents.Z
iegler-NattaCatalysts and
Polymerization by John B
oor Jr.

(Academic Press), Journal
of Macromorecular Science-
Reviews in Macromolecular
Chemistry and Physics, C24
(3) 355-385 (1984), same C25 (1)
578-597 (1985)).

Preferred examples of stereoregularity improvers or electron-donating compounds include oxygen-containing compounds such as ethers, esters, orthoesters, and alkoxy silicon compounds, and further examples of electron-donating compounds include alcohols, aldehydes, and water. Available for use.

As the aluminum compound, trialkylaluminum, dialkylaluminum halide, alkylaluminum sesquihalide, alkyl aluminum civalide can be used, and examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, hexyl group, etc. Examples of the halide include chlorine, bromine, and iodine.

There is no particular restriction on the polymerization ratio of alkenylsilane and propylene as long as the resulting polymer maintains crystallinity, but usually alkenylsilane has a catalytic activity of 30 to 0.01 mol% during polymerization. , or for use as a polypropylene composition after reacting with a polysiloxane. The molecular weight of the polymer is not particularly limited and may be determined according to the purpose of use as a composition.

For example, if it is used as is for molding purposes, 13
5°C Tetralin/8? F! The intrinsic viscosity measured in terms of L is generally about 1 to 5, and when used as a blend material for modifying other polyolefins, it is generally about 0.1 to 3.

In the present invention, the OH group-containing polybutadiene to be heated and mixed with the crystalline propylene copolymer obtained by using a stereoregular catalyst from the above-mentioned alkenylsilane and propylene is HO-(CHz-CH=C)I- Hz), -
R or HO-(CHz-CH=CH-C)Iz)ll
-(CH2-CH(CH=CH2))--R (in the formula, R is an OH group or hydrogen, m and n are integers, and some double bonds may be hydrated) Things are already produced on an industrial scale and can be used.

In the present invention, when heating and mixing the above two types of polymers, an organic acid or a salt thereof, an organic base, or an alkoxy compound of an alkali metal or alkaline earth metal,
Alternatively, compounds selected from hydroxides and oxides, ie, various compounds known as siloxane condensation catalysts, particularly salts of alkali metal alkoxides and carboxylic acids such as tin and lead may also be present.

In the present invention, there is no particular restriction on the method of mixing two types of polymers, and the two polymers can be sufficiently heated and mixed by a general method such as premixing with a Henschel mixer, then melt-mixing with an extruder, and granulating.

Moreover, it is also possible to heat when mixing with a Henschel, and it is also possible to mix using a roll. At this time, mixing additives such as various known stabilizers,
Alternatively, it is of course possible to add and mix other polymers, especially polyolefins.

In the present invention, the above-mentioned alkenylsilane and propylene are added to a composition obtained by heating and melting a crystalline propylene copolymer obtained using a stereoregular catalyst and a polybutadiene containing an OH group, and if necessary, other crystalline copolymers are added to the composition. Polypropylene, for example, may be mixed with polymers of various molecular weights, random or block copolymers with other olefins such as ethylene, etc. If the polyolefin to be bonded is polypropylene, those of similar composition and molecular weight may be used. is also a law,
It is sufficient to use a homopolymer of polypropylene. In order to obtain the crystalline polypropylene, the above catalyst and polymerization method may be used during polymerization.

In the present invention, in a composition obtained by melt-mixing crystalline polypropylene containing alkenylsilane and polybutadiene containing an OH group, or in a mixture of this and crystalline polypropylene not containing the silane compound, alkenylsilane The blending amount of the crystalline polypropylene containing alkenylsilane varies depending on the amount of alkenylsilane in the crystalline polypropylene containing alkenylsilane, but after mixing the alkenylsilane unit is 1wt% of the total composition.
Generally, the amount is about 10 wt ppm.

The composition of the present invention is normally used by sandwiching a polyolefin layer and a polar group-containing polymer layer and adhering the two, but the composition of the present invention is mixed with a polyolefin and used as a polyolefin layer. You can also do that.

〔Example〕

The present invention will be further explained by showing examples below.

Example 1 A vibratory mill equipped with four grinding pots each having an internal volume of 42 and containing 9 kg of steel balls with a diameter of 12 m+w was prepared. 300 g of magnesium chloride, 60 g of tetraethoxysilane, and 45 d of α,α,α-trichlorotoluene were placed in each pot under a nitrogen atmosphere and pulverized for 40 hours. 300 g of the co-pulverized material thus obtained was placed in a 51 flask, 1.51 g of titanium tetrachloride and 1.5 g of toluene were added, and the mixture was heated at 100°C for 30 g.
The mixture was stirred for a minute, and then the supernatant was removed. Add titanium tetrachloride (1.52 °C) and toluene (1.5 °C) again, stir at 100 °C for 30 minutes, remove the supernatant liquid, and wash the solid content repeatedly with rhohexane to obtain a transition metal catalyst slurry. Obtained. A sample was taken and the titanium content was analyzed and found to be 1.9 wt%.

In a pressure-resistant glass autoclave with an internal volume of 200 d, under a nitrogen atmosphere, 40 ml of toluene and 2 g of the above transition metal catalyst and 0.128 al of diethylaluminum chloride! , 0.06 d of methyl p-toluate and 0.20 d of triethylaluminum, and then 4.0 d of vinylsilane. Og was injected under pressure, then propylene was injected until the amount reached 5 kg/cJ, and polymerization was carried out at 70°C for 2 hours at a constant pressure. Thereafter, the slurry was taken out, filtered and dried to obtain 28 g of powder. Intrinsic viscosity measured in tetralin solution at 135 °C (
(hereinafter abbreviated as η), lOo (/
When the melting point and crystallization temperature were measured as the maximum peak temperature by increasing or decreasing the temperature with +win, η was 1.28.
It was crystalline polypropylene with a melting point of 148°C and a crystallization temperature of 105°C. According to elemental analysis, it contained 2.5 wt% of vinylsilane units.

0.5 g of sodium was dissolved in 100 ml of toluene and 150 ml of OH-containing polybutadiene (808-1000-2,5) manufactured by Nisseki Kagaku ■, and then 5 g of the above vinylsilane-containing polypropylene was dispersed therein and heated at 110"C for 2 hours.
heated for an hour.

A large amount of methyl ethyl ketone was added and the filtered powder was washed with methyl ethyl ketone and dried.

According to the infrared absorption spectrum, absorption due to 5i-H bond decreased and absorption of butadiene was observed. The reaction amount of butadiene calculated from the amount of double bonds was 7wtχ relative to polypropylene.

Separately, propylene was polymerized and extracted with η-1.65 using a Soxhlet extractor (hereinafter abbreviated as II). Powder weight after extraction/powder weight before extraction was calculated as 100
Polypropylene having a percentage of 97.1% (expressed as a fraction) was obtained.

To 200 g of the obtained polypropylene powder, 5 g of the above copolymer, a phenolic stabilizer at a weight ratio of 10/10000 (to polypropylene), and 1 part calcium stearate were added.
A 5/10,000 weight ratio (to polypropylene) was added and granulated to obtain an adhesive resin composition.

To measure the adhesive strength, we used EVAL (Kuraray EP-
F) sheet with a thickness of 0.2 mm and a sheet of polypropylene with a thickness of -0.2 mm (manufactured with the above homopolymer)
A sheet of the above adhesive composition (thickness O, 1 m+o
) were sandwiched and crimped at 220°C, 4g/C4, 3min. This multilayer sheet has a peel strength of 2 kg/ci (T-type peel strength was measured using an Instron tensile tester on a test piece with a width of 2.5 Ω at 23°C and a tensile rate of 100 g/g I n). ) That was it.

Comparative Example 1 The same procedure as in Example 1 was carried out except that a homopolymer of polypropylene was used instead of the copolymer of alkenylsilane and propylene, but the polybutadiene did not react at all.

Example 2 Example 1 except that allylsilane was used instead of vinylsilane.
I did the same thing.

Here, the copolymer is allylsilane 3. ht%, η was 1.29, and the melting point was 138°C.

The content of butadiene was 611tχ.

Example 3 5 g of the copolymer obtained in Example 1 was mixed with 0.2 g of OR-containing butadiene in which the same sodium as in Example 1 was dissolved, and then pressed repeatedly at 230° C. to form a sheet. According to the infrared absorption spectrum, SiH bonds were reduced.

〔Effect of the invention〕

The composition of the present invention has extremely excellent adhesive strength and is extremely valuable industrially.

Patent applicant: Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 1. An adhesive resin composition obtained by heating and mixing a crystalline propylene copolymer obtained by polymerizing alkenylsilane and/or alkenylchlorosilane and propylene using a stereoregular catalyst, and polybutadiene containing an OH group. thing.