JP2505508B2 - Adhesive polypropylene resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an adhesive polypropylene resin composition. More specifically, it relates to a polypropylene resin composition for adhesion, which is suitable for adhering a polymer containing a polar group such as a saponified ethylene-vinyl acetate copolymer, nylon or polyester, and a polyolefin, particularly polypropylene.

[Conventional technology]

It has been widely practiced to make a multilayer structure with other polymers, particularly polar group-containing polymers, for the purpose of imparting the properties which polyolefin originally does not have, such as gas barrier property, by utilizing the properties of polyolefin. Since polyolefins and polar group-containing polymers are not compatible by nature, they are not adhered by simply sticking them together, and an adhesive resin is sandwiched between them. For this purpose, maleic anhydride was grafted onto polyolefin. A polymer is utilized.

[Problems to be solved by the invention]

A polymer obtained by grafting maleic anhydride onto a polyolefin has a certain effect in improving the adhesiveness between the polyolefin and the polar group-containing polymer, but it is still insufficient especially for the adhesion between EVAL and polypropylene and further It has been desired to develop an improved resin composition for bonding.

[Means for Solving Problems] The inventors of the present invention have earnestly searched for a resin composition excellent in adhesion between a polyolefin and another polar group-containing polymer, which has solved the above problems, and completed the present invention.

That is, the present invention is an adhesive polypropylene resin composition obtained by melt-mixing a crystalline propylene copolymer obtained by using alkenylchlorosilane and propylene using a stereoregular catalyst and crystalline polypropylene containing no alkenylchlorosilane. Is.

In the present invention, as a method for producing a crystalline propylene copolymer obtained by using alkenylchlorosilane and propylene using a stereoregular catalyst, for example, using ω-alkenylchlorosilane as a copolymerization monomer, U.S. Pat.
No. 240,768, the method can be used as it is. At least 1 as alkenylchlorosilane
Those having one Si-Cl bond are used, for example, vinyltrichlorosilane, allyltrichlorosilane, butenyltrichlorosilane, pentenyltrichlorosilane, and one or two of these monomers' Si-Cl bonds are alkyl groups or hydrogen. Examples include substituted ones. A number of performance-improved catalysts have since been disclosed as stereoregular catalysts, and they can be used. Also, as the polymerization method, a bulk polymerization method or a gas phase polymerization method can be adopted in addition to the solvent method using an inert solvent. Here, the stereoregular catalyst is preferably exemplified by a catalyst system composed of a transition metal catalyst and an organometallic compound, and a titanium halide is preferably used as the transition metal catalyst. A catalyst system composed of titanium trichloride obtained by reduction or those modified with an electron donating compound and an organoaluminum compound, and optionally a stereoregularity improving agent such as an oxygen-containing organic compound, a carrier such as magnesium halide Alternatively, a transition metal catalyst obtained by supporting them with an electron-donating compound and supporting titanium halide or a reaction product of magnesium chloride and alcohol is dissolved in a hydrocarbon solvent, and then used as a precipitating agent such as titanium tetrachloride. This makes it insoluble in hydrocarbon solvents and, if necessary, charges the ester, ether, etc. A catalyst system comprising a transition metal catalyst obtained by treating with a donor compound and then supporting titanium tetrachloride and an organoaluminum compound, and optionally a stereoregularity improving agent such as an oxygen-containing organic compound (for example, Various examples are described in the literature of Ziegler-Natta Catalysts and Polym.
erization by John Boor Jr., (Academic Press), Jour
nal of Macromorecular Sience−Reviews in Macromole
cular Chemistry and Physics, C24 (3), 355-385 (19
84), C25 (1), 578-597 (1985)).

Here, as the stereoregularity improver or electron donating compound, oxygen-containing compounds such as ethers, esters, orthoesters and alkoxy silicon compounds can be preferably exemplified, and as the electron donating compound, alcohol, aldehyde, water and the like can also be used. It can be used.

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

Here, the polymerization ratio of alkenylchlorosilane and propylene is not particularly limited as long as the obtained polymer maintains crystallinity, but alkenylchlorosilane is usually 30
It is preferable to set the content to mol% to 0.01 mol% because of the catalytic activity at the time of polymerization, the mixing with the crystalline polypropylene to be mixed, and the sufficient effect of improving the physical properties. The molecular weight of the polymer is not particularly limited, but it should be extremely high, for example, not more than 10 as the intrinsic viscosity measured with a 135 ° C. tetralin solution.

In the present invention, there is no particular limitation as the crystalline polypropylene to be mixed with the crystalline propylene copolymer obtained by using the alkenylchlorosilane and propylene with a release regular catalyst, and polymers of various molecular weights as necessary, Alternatively, a random or block copolymer with another olefin such as ethylene can be used. If the polyolefin to be adhered is polypropylene, one having the same composition and molecular weight is used, but 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 in the polymerization.

In the present invention, a compound selected from an organic acid or a salt thereof, an organic base, an alkoxy compound of an alkali metal or an alkaline earth metal, a hydroxide or an oxide can be added, and a specific compound is a siloxane condensation catalyst. Examples of various compounds known as are available, and alkali metal alkoxy compounds and salts of carboxylic acids such as tin and lead are particularly preferably used.

In the present invention, the mixing ratio of the crystalline propylene copolymer containing alkenylchlorosilane and the crystalline polypropylene not containing the silane compound varies depending on the amount of alkenylchlorosilane in the crystalline polypropylene containing alkenylchlorosilane. After mixing, the alkenylsilane unit is generally present in an amount of 1 wt% to 10 wt ppm in the entire composition.

The composition of the present invention, if necessary, further before melt mixing,
Alternatively, it can be used after being melt-mixed and treated with a lower alcohol such as methanol, ethanol, propanol or butanol.

〔Example〕

 The present invention will be further described with reference to examples.

Example 1 A vibration mill equipped with four grinding pots having an inner volume of 4 and containing 9 kg of steel balls having a diameter of 12 mm is prepared. Under a nitrogen atmosphere, 300 g of magnesium chloride, 60 ml of tetraethoxysilane and 45 ml of α, α, α-trichlorotoluene were placed in each pot and pulverized for 40 hours. 5 g of 300 g of the co-ground product thus obtained
Place it in a flask with titanium tetrachloride 1.5 and toluene
1.5 was added, the mixture was stirred at 100 ° C for 30 minutes, the supernatant was removed, and then titanium tetrachloride 1.5 and toluene 1.5 were added again.
Was added, the mixture was stirred at 100 ° C. for 30 minutes, and the supernatant was removed. Then, the solid content was repeatedly washed with n-hexane to obtain a transition metal catalyst slurry. Titanium content was 1.9 wt% when part of it was sampled and titanium content was analyzed.

To a pressure-resistant glass autoclave with an internal volume of 200 ml, 40 ml of toluene under a nitrogen atmosphere, 100 mg of the above transition metal catalyst, 0.128 ml of diethylaluminum chloride, 0.06 ml of methyl p-toluate and 0.20 ml of triethylaluminum were added, and then 6.0 g of trichlorovinylsilane was injected under pressure. Then, propylene was inserted to 5 kg / cm ² and polymerization was carried out at 70 ° C. under a constant pressure for 2 hours. Then, the slurry was taken out, filtered and dried to obtain 28 g of powder. Intrinsic viscosity measured with a tetralin solution at 135 ° C (hereinafter abbreviated as η), where the melting point and crystallization temperature were measured as the maximum peak temperature by raising or lowering the temperature at 10 ° C / min using a differential thermal analyzer, The obtained powder has an η of 1.41, a melting point of 148 ° C and a crystallization temperature of 102.
It was a crystalline polypropylene having a temperature of ° C. According to elemental analysis, it contained 1.3 wt% of chlorovinylsilane unit.

In addition, propylene was separately polymerized, and η was 1.65, and the extraction residual ratio was obtained when extracted with a Soxhlet extractor (hereinafter abbreviated as II).
A polypropylene having a powder weight after extraction / powder weight before extraction (expressed as a percentage) of 97.1% was obtained.

The above copolymer was added to 900 g of the obtained polypropylene powder.
20 g, a phenolic stabilizer 10/10000 weight ratio (to polypropylene) and calcium stearate 15/10000 weight ratio were added and granulated to obtain a mixture.

Eval (made by Kuraray Co., Ltd.) to measure the adhesive strength
EP-F) 0.2 mm thick sheet and polypropylene thickness
220 sheets of the above-mentioned adhesive composition (thickness 0.1 mm) are sandwiched between 0.2 mm sheets (made of the above homopolymer), 220
℃, it was pressed at 4g / cm ^2, 3min. This multilayer sheet has a peel strength of 2 kg / cm (width using an Instron tensile tester
For the 2.5 cm test piece, the T-type peel strength was measured at 23 ° C. and a pulling speed of 100 mm / min) or more).

Example 2 The resin composition for adhesion obtained in Example 1 was formed into a sheet and treated in ethanol at 40 ° C. for 1 hour, and then in Example 1
The adhesive strength was measured in the same manner as in. As a result, the peel strength is 2k
It was more than g / cm.

Example 3 The peel strength was 2 kg / cm or more when evaluated in the same manner as in Example 1 except that a copolymer obtained by using trichloroallylsilane in place of trichlorovinylsilane was used.

The copolymer used here contained 2.3% by weight of allylchlorosilane, had η of 1.34 and a melting point of 135 ° C.

Example 4 Further, the same operation as in Example 1 was carried out except that 0.1 g of lithium ethoxide was added, and the peel strength was 2 kg / cm ² or more.

〔The invention's effect〕

The polypropylene resin composition for adhesion of the present invention has excellent adhesive strength and is extremely significant industrially.

 ─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-1-165645 (JP, A) JP-A-1-165642 (JP, A) JP-A 64-43534 (JP, A) JP-B 7- 25958 (JP, B2) Japanese Patent Publication 7-68421 (JP, B2)

Claims (1)

(57) [Claims] 1. Adhesive polypropylene prepared by melt-mixing a crystalline propylene copolymer obtained by polymerizing alkenylchlorosilane and propylene using a stereoregular catalyst, and crystalline polypropylene containing no alkenylchlorosilane. Resin composition.