JPH0725955B2 - Amorphous polyolefin composition and adhesive composition using the same - Google Patents

Description

TECHNICAL FIELD The present invention relates to an amorphous polyolefin composition which is excellent in heat resistance, weather resistance, flexibility, fluidity, processability and the like and is inexpensive.

The amorphous polyolefin composition of the present invention comprises a partially hydrogenated product of an amorphous polyolefin polymer and an aromatic vinyl / conjugated diene block copolymer.

By blending a tackifier or the like with the amorphous polyolefin composition of the present invention, an adhesive composition having a long open time and suitable for bonding polypropylene films and the like is obtained.

[Conventional technology]

The thermoplastic elastomer can be molded by a molding method similar to that of ordinary thermoplastics, and exhibits good rubber elasticity without vulcanization. Therefore, it has come to be widely used in fields in which the above characteristics are utilized, such as footwear, industrial parts, automobile parts, household electric appliance parts, electric wire coatings, plastic reforming and other miscellaneous goods.

Among them, aromatic vinyl / conjugated diene block copolymers having an aromatic vinyl block and a conjugated diene block are more widely used in fields where rubber elasticity is important because they are superior in rubber properties to other moldable materials. ing.

However, since the aromatic vinyl-conjugated diene block copolymer has an unsaturated double bond in the polymer chain, it has a drawback that it is inferior in heat resistance and weather resistance.

Therefore, there are many problems when used for a long time outdoors, for example, as an elastic sealant.

Although injection molding is possible, injection molding is more difficult than general-purpose thermoplastic resins such as polypropylene and polyethylene.

In order to solve the drawbacks of conventional aromatic vinyl-conjugated diene block copolymers that are inferior in weather resistance and heat resistance, hydrogenation is mainly performed under the condition that conjugated diene moieties are hydrogenated, that is, partial hydrogenation. Has been tried. Japanese Patent Office 42
-8704, Japanese Patent Publication No. 42-8933, Japanese Patent Publication No. 43-6636, Japanese Patent Publication No. 43-19960, Japanese Patent Publication No. 46-20814, Japanese Patent Publication No. 48-30151
The specification of the publication discloses an example in which an aromatic vinyl / conjugated diene block copolymer is partially hydrogenated using a nickel-based or cobalt-based catalyst.

By the partial hydrogenation, the weather resistance, heat resistance and processability of the above aromatic vinyl / conjugated diene block copolymer were greatly improved. However, since a step of partial hydrogenation is added, there is a problem that it is more expensive than a block copolymer without partial hydrogenation. For this reason, the usage tends to be largely limited.

Therefore, heat resistance and weather resistance equivalent to or higher than the above-mentioned partially hydrogenated product of the aromatic vinyl-conjugated diene block copolymer,
Various attempts have been made to obtain a cheaper composition having processability.

For example, it has been attempted to blend a partially hydrogenated product of an aromatic vinyl / conjugated diene block copolymer with a polyolefin (JP-A-61-155446).

By blending with polyolefin, not only mechanical strength but also weather resistance and heat resistance have been greatly improved.

[Problems to be Solved by the Present Invention]

However, crystalline polypropylene is used as the polyolefin in the above composition. Therefore, the obtained composition tends to be hard, and conversely has a low impact resilience,
The performance as rubber tends to be low. For this reason,
It was not suitable for applications such as elastic sealants where flexibility is particularly required.

Further, this composition has a drawback that the fluidity is low.
Therefore, an adhesive composition obtained by blending a tackifier or the like with this composition or an adhesive composition such as a pressure-sensitive adhesive has a drawback that the open time is short.

The present invention is an invention made to solve the above problems. That is, by blending an amorphous polyolefin polymer with a partially hydrogenated product of an aromatic vinyl / conjugated diene copolymer, it has excellent heat resistance, weather resistance, repulsion, flexibility, fluidity, etc. An object of the present invention is to provide an amorphous polyolefin composition which is cheaper than the partially hydrogenated product itself of the vinyl / conjugated diene block copolymer.

[Means for solving problems]

The present invention relates to (a) an amorphous polyolefin polymer having a number average molecular weight of 1000 to 20,000 ... 3 to 80% by weight, and (b) a partial hydrogenated product of a block copolymer of an aromatic vinyl-conjugated diene. To 20% by weight of the amorphous polyolefin composition.

In the amorphous polyolefin composition of the present invention, the content of the amorphous polyolefin polymer must be 3% by weight or more. When the content is less than 3% by weight, heat resistance, weather resistance, fluidity and the like are hardly improved. If the content exceeds 80% by weight, impact resilience, mechanical strength,
In addition, the heat distortion temperature and the like become too low, which makes it unsuitable for use as a thermoplastic elastomer.

The amorphous polyolefin polymer used in the present invention,
There are propylene homopolymers and random copolymers of propylene and ethylene and / or α-olefins.

Further, the above-mentioned amorphous polyolefin polymers include not only those by-produced but also those produced for the purpose and those produced by the production of polypropylene such as atactic polypropylene. Here, the term “produced by purpose, not by-produced” means that monomers such as propylene, ethylene and α-olefin are used under specific polymerization conditions / catalyst composition for the purpose of obtaining an amorphous polyolefin polymer. It means that it was obtained by polymerizing in 1. and is not a by-product.

In the present invention, heat resistance, weather resistance, low temperature characteristics, flexibility, fluidity and the like can be improved by using any of the amorphous polyolefin polymers.

However, the quality of the objectively produced amorphous polyolefin polymer is high, because the quality can be easily controlled by the monomer composition, the polymerization conditions, the catalyst composition and the like during the production. Further, by changing the monomer composition and the like, it is possible to obtain an amorphous polyolefin polymer having various characteristics.

Therefore, it is preferable that the amorphous polyolefin polymer is not produced as a by-product but is produced by the purpose.

The molecular weight of the amorphous polyolefin polymer is preferably in the range of 1000 to 20,000. The propylene content is 40% by weight or more.

When the molecular weight is less than 1000, it becomes soft even at room temperature and the cohesive force becomes too weak when used in an adhesive or the like, which is not preferable. On the other hand, when the molecular weight exceeds 20,000, the melt viscosity increases. Therefore, even if an amorphous polyolefin polymer having a molecular weight exceeding 20,000 is used, the fluidity of the amorphous polyolefin composition is not improved.

If the propylene content is less than 40% by weight, it will be too soft even at room temperature and the softening point will be low, so it cannot be used as a sealant for heat resistant applications.

As the random copolymer of propylene and ethylene and / or α-olefin, a propylene / ethylene random copolymer or a propylene / α-olefin random copolymer is particularly preferable.

The ethylene content of the propylene / ethylene random copolymer is preferably in the range of 8 to 30% by weight.

Examples of the α-olefin of the propylene / α-olefin random copolymer include 2-methyl-propylene and 1
-Butene, 2-methyl-1-butene, 3-methyl-1-
Butene, 2-ethyl-1-butene, 1-pentene, 2-
Methyl-1-pentene, 3-methyl-1-pentene, 4
-Methyl-1-pentene, 1-hexene, 2-ethyl-
1-Pentene, 3-ethyl-1-pentene, 4-ethyl-1-pentene and the like can be used. However, from the viewpoints of price, heat resistance, weather resistance, and mechanical strength, a propylene / 1-butene random copolymer is particularly preferable. The content of 1-butene in the propylene / 1-butene random copolymer is particularly preferably in the range of 10 to 60% by weight.

In order to produce the above amorphous polyolefin polymer, for example, the following polymerization method can be used. In the presence of a catalyst composed of titanium chloride supported on magnesium chloride and trialkylaluminum, α-olefin such as 1-butene or ethylene is introduced as needed in a hydrogen atmosphere while liquefying propylene. It can be produced by a polymerization method such as.

The partially hydrogenated aromatic vinyl / conjugated diene block copolymer is a partially hydrogenated aromatic vinyl / conjugated diene block copolymer represented by the following general formula.
Some examples of this general formula are shown below.

(1) A-B-A, (2) (A-B) n (3) B- (A-B) n (4) (A-B) m-A-X- (A-B) n ( 5) (A-B) m-X- (B-A) n Etc.

In the above general formula, A represents a polymer block mainly containing an aromatic vinyl, and B represents a polymer block mainly containing a conjugated diene. X represents a coupling agent.

The content of aromatic vinyl is preferably in the range of 5 to 50% by weight, and more preferably in the range of 5 to 30% by weight.

If the content of aromatic vinyl exceeds 50% by weight, the compatibility with the amorphous polyolefin polymer is poor, and a uniform amorphous polyolefin composition cannot be obtained.

Examples of the aromatic vinyl include styrene, α-methylstyrene, vinyltoluene, ethylstyrene, p-tert.
-Butylstyrene, o-chlorostyrene, p-chlorostyrene, divinylbenzene and the like are used. These aromatic vinyls may be used alone or in combination of two or more kinds, but styrene is particularly preferable.

As the conjugated diene, 1,3-butadiene, isoprene,
1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, chloroprene and the like are used. Of these, 1,3-butadiene and isoprene are particularly preferable.

The above aromatic vinyl / conjugated diene block copolymer is obtained by sequentially performing block copolymerization of these monomers with a lithium alkyl catalyst. Also,
The aromatic vinyl compound and the conjugated diene compound may be preliminarily polymerized and then coupled with a coupling agent.

The partial hydrogenation can be carried out by a known hydrogenation catalyst, for example, a supported catalyst of a noble metal such as platinum or palladium, an organocobalt or nickel compound, or a complex of these compounds with another organometallic compound. Most preferred of these catalysts are titanocene compounds. The titanocene compound has extremely high activity as a catalyst for partial hydrogenation of an aromatic vinyl / conjugated diene block copolymer, and even if it remains in the partial hydrogenation product of the block copolymer, it has a bad influence on heat resistance. Because it does not give.

Partial hydrogenation is preferably carried out to the extent that at least 80%, preferably 90% or more of the conjugated diene moieties are hydrogenated. However, the proportion of hydrogenated aromatic vinyl moieties is preferably in the range of 20% or less, and more preferably in the range of 5% or less.

When the hydrogenation ratio of the conjugated diene portion is less than 80%, the polar difference from the amorphous polyolefin polymer becomes too large due to the double bond of the conjugated diene contained in the block copolymer. Therefore, a uniform and transparent amorphous polyolefin composition cannot be obtained.

The amorphous polyolefin composition of the present invention can be prepared by mechanically blending a partially hydrogenated product of an aromatic vinyl / conjugated diene block copolymer with an amorphous polyolefin polymer. A blend of partially hydrogenated aromatic vinyl / conjugated diene block copolymer and amorphous polyolefin polymer is usually used for kneading rubber or resin in Banbury mixer, Brabender mixer, kneader, kneading extruder, etc. It can be performed using the device.

To the amorphous polyolefin composition of the present invention, various inorganic fillers and stabilizers may be further added to further improve weather resistance and heat stability. Examples of the inorganic filler include calcium carbonate, talc, carbon black, titanium oxide, white carbon, magnesium carbonate, clay and barium sulfate. Examples of the stabilizer include hindered amine compounds, hindered phenol compounds and benzotriallyzole compounds.

An adhesive composition such as a sealant, an adhesive or a pressure-sensitive adhesive can be prepared by blending the amorphous polyolefin composition of the present invention with a tackifier and resins.

The tackifier refers to a natural resin or a synthetic resin such as natural rosin or coumarone-indene resin, which is added for imparting adhesiveness or tackiness to the amorphous polyolefin composition.

In the above adhesive composition, the tackifier is 20 to 5 relative to 100 parts by weight of the amorphous polyolefin composition of the present invention.
00 parts by weight, and resins are 0 to 300 parts by weight.

If the tackifier is less than 20 parts by weight, the adhesive composition,
It does not exhibit sufficient adhesiveness for practical use as a sealant, adhesive, adhesive, etc.

Further, when the blending ratio of the tackifier exceeds 500 parts by weight, the excellent properties such as heat resistance, weather resistance, flexibility, and fluidity of the amorphous polyolefin composition of the present invention, in the adhesive composition. It will not be reflected sufficiently.

Tackifiers include natural rosin (gum rosin, wood rosin, tall oil rosin, etc.), modified rosin (polymerized rosin,
Hydrogenated rosin, maleated rosin, etc.), coumarone-indene resin, terpene-based resin, petroleum resin, and phenol-based resin.

Resins are ethylene, excluding resins used as tackifiers.
Vinyl acetate copolymer, ethylene / acrylic acid copolymer,
Ethylene / ethyl acrylate copolymer, ethylene / methyl acrylate copolymer, styrene / ethylene / butylene / styrene copolymer, ethylene / propylene copolymer or ethylene / butene copolymer having a molecular weight of 30,000 or more, polybutene wax, Paraffin wax, microcrystalline wax, polyethylene wax, chlorinated paraffin wax, oxidized paraffin wax, and maleated paraffin wax.

The adhesive composition can be prepared as follows. The amorphous polyolefin composition of the present invention may be prepared in advance, and then the tackifier or resin may be blended in a predetermined amount. In addition, amorphous polyolefin polymer, aromatic vinyl
The partially hydrogenated product of the conjugated diene block copolymer and the resin may be blended at the same time.

Furthermore, the amorphous polyolefin composition of the present invention can be used as a molding material by blending a filler, a flame retardant, a pigment, a resin, a plasticizer, an oil, a stabilizer and the like.

As the filler, those commonly used as inorganic fillers such as calcium carbonate, talc, carbon black, titanium oxide, white carbon, magnesium carbonate, clay and beryllium sulfate can be used.

Flame retardants include tricresyl phosphate, trischloroethyl phosphate, tris (dichloropropyl)
Phosphate, triphenyl phosphate, tris (dibromopropyl) phosphate, ethane tetrabromide, chlorinated paraffin, antimony oxide, chlorentic acid, phosphorus-containing polyol, bromine-containing polyol, aluminum hydroxide,
Magnesium hydroxide or the like can be used.

The pigments are titanium oxide, cadmium pigments, yellow lead, red iron oxide,
Ultramarine blue, cobalt blue, copper phthalocyanine pigment, quinacdrine pigment, azo pigment, aniline black, carbon black and the like can be used.

As the resins, polyester, polyolefin, polycarbonate, acetal resin, thermoplastic polyurethane, halogenated thermoplastic resin, polystyrene and the like can be used.

As the plasticizer, di-m-butyl phthalate, di-2-ethylhexyl phthalate, diisodecyl phthalate, diisotridecyl phthalate, butylbenzyl phthalate, di-2-ethylhexyl adipate, di-2-ethylhexyl sebacate, Tricresyl phosphate or the like can be used.

As the oil, paraffin oil, naphthene oil and the like can be used.

〔Example〕

Examples of the amorphous polyolefin composition and the adhesive composition of the present invention are shown below.

The physical properties shown in the following examples and comparative examples were measured as follows.

・ Tensile breaking strength, tensile breaking elongation, 300% modulus, and hardness …… JIS K6301 ・ Rebound resilience (Dunlop repulsion) …… British Standard S9
03 ・ Melt index …… JIS K7210 ・ Heat resistance test …… 140 ° C The tensile rupture strength and tensile rupture elongation retention after standing for 10 hours in an air oven were measured.

・ Weather resistance test: A tensile rupture strength and a tensile rupture elongation retention rate after standing for 500 hours were measured in a sunshine weather o-meter (carbon arc, 40 ° C, 50% humidity).

・ Temperature distortion temperature ... Temperature rise 20 using DuPont TMA device
The temperature at the time of needle penetration of 0.1 mm was measured under the condition of ° C / min.

Example 1 As a partially hydrogenated product of an aromatic vinyl / conjugated diene block copolymer, a partially hydrogenated product of a styrene / butadiene block copolymer (Shell Chemical's Kraton G1657X)
It was used. As an amorphous polyolefin polymer, propylene / ethylene random copolymer (Lexen Co.
REXTAC B3A15 (Propylene / ethylene polymerization ratio = 85: 1
5) A number average molecular weight of 2500) was used.

75% by weight of the partially hydrogenated product of the above styrene / butadiene block copolymer was kneaded with 25% by weight of the above propylene / ethylene random copolymer in a Brabender mixer to prepare an amorphous polyolefin composition.

This amorphous polyolefin composition is compression molded to form a sheet, which has tensile properties, melt index, impact resilience,
Hardness, heat resistance and weather resistance were measured. The results are shown in Table 1.

Example 2 50% by weight of a partially hydrogenated product of a styrene / butadiene block copolymer (Clayton G1657X manufactured by Shell Chemical Co., Ltd.), a propylene / ethylene random copolymer (REXTAC B3A15 manufactured by US Lexen Co., Ltd. (propylene / ethylene weight ratio = 85:
A sheet was prepared in the same manner as in Example 1 except that 50% by weight of 15)) was used, and the tensile properties, melt index, impact resilience, hardness, heat resistance, and weather resistance were measured. The results are shown in Table 1.

Example 3 As an amorphous polyolefin polymer, propylene / 1-
Butene random copolymer (REXTAC
An amorphous polyolefin composition was prepared in the same manner as in Example 1 except that E4 (weight ratio of propylene / 1-butene = 60: 40, number average molecular weight 6700) was used.

A sheet was formed from this amorphous polyolefin composition by compression molding in the same manner as in Example 1. About this sheet, tensile properties, melt index, impact resilience, hardness,
The heat resistance and weather resistance were measured. The results are shown in Table 1.

Example 4 35% by weight of partially hydrogenated styrene / butadiene block copolymer (Clayton G1657X manufactured by Shell Chemical Co., Ltd.), propylene / ethylene random copolymer (manufactured by Lexen, USA)
REXTAC B3A15 (Propylene / Ethylene weight ratio = 85: 1
5)) 35% by weight and 30% by weight of alicyclic petroleum resin (Arakawa Chemical Co., Alcon P-125) as a tackifier,
The adhesive composition was prepared by melting and mixing at ° C.

This adhesive composition was compression molded in the same manner as in Example 1 to prepare a sheet. The tensile properties, melt index, impact resilience, hardness, heat resistance, and weather resistance of this sheet were measured. The results are shown in Table 1.

Further, this adhesive composition was applied on a biaxially oriented polypropylene film having a thickness of 20 μm at a temperature of 140 ° C. to a thickness of 30 μm, and after 10 seconds, a polypropylene film of the same kind was pressure-bonded and laminated to prepare a test piece. .

This test piece is cut on a 25 mm wide strip, and the peeling speed is 300 mm /
The peel strength was measured under the condition of the ambient temperature of 25 ° C. for min. The peel strength was 13.0 kg / 25 mm.

Comparative Example 1 From a partially hydrogenated product of a styrene / butadiene block copolymer (Clayton G1657X manufactured by Shell Chemical Co., Ltd.), Example 1 was obtained.
A sheet was created in the same manner as. The tensile properties, melt index, impact resilience, hardness, heat resistance, and weather resistance of this sheet were measured. The results are shown in Table 1.

Comparative Example 2 A sheet was prepared in the same manner as in Example 1 except that crystalline polypropylene (J130G manufactured by Ube Industries, Ltd.) was blended instead of the amorphous polyolefin polymer. About this sheet, tensile properties, melt index, impact resilience, hardness,
The heat resistance and weather resistance were measured. The results are shown in Table 1.

Comparative Example 3 50% by weight of partially hydrogenated styrene / butadiene block copolymer (Clayton G1657X made by Shell Chemical Co., Ltd.) and 50% by weight of crystalline polypropylene (J130G made by Ube Industries)
A sheet was prepared in the same manner as in Comparative Example 2 except that it was used. About this sheet, tensile properties, melt index,
The impact resilience, hardness, heat resistance and weather resistance were measured. The results are shown in Table 1.

Comparative Example 4 35% by weight of a partially hydrogenated styrene / butadiene block copolymer (Clayton G1657X manufactured by Shell Chemical Co., Ltd.), 35% by weight of crystalline polypropylene (J130G manufactured by Ube Industries), and an alicyclic petroleum resin as a tackifier ( 30% by weight of Alcon P-125) manufactured by Arakawa Chemical Co., Ltd. was melted and mixed at 200 ° C. to prepare an adhesive composition.

This adhesive composition was applied on a biaxially oriented polypropylene film having a thickness of 20 μm at 140 ° C. to a thickness of 30 μm, and after 10 seconds, a polypropylene film of the same kind was pressure-bonded, but they could not be bonded.

Therefore, the temperature is further raised to 190 ° C and 30
It was applied to a thickness of μm, and after 10 seconds, a polypropylene film of the same kind was pressure-bonded and laminated.

However, since the coating temperature of the adhesive plastic material was too high, the polypropylene film contracted and wrinkles occurred.

Therefore, when the peel strength was measured, the film was cut.

From the results shown in Table 1, the amorphous polyolefin composition of the present invention (Examples 1, 2, and 3) shows that styrene-butadiene, which is a kind of partially hydrogenated aromatic vinyl / conjugated diene block copolymer. It can be seen that the block copolymer shows higher heat resistance and weather resistance than the partially hydrogenated product of the block copolymer (Comparative Example 1).

In addition, the amorphous polyolefin composition of the present invention is
Compared to partially hydrogenated butadiene block copolymer,
MI (Molecular Index) is small (Examples 1, 2, 3, 4 and Comparative Example 1). From this, it is also clear that the liquidity is improved.

Compared with conventional polyolefin compositions (comparative examples 2 and 3) composed of a partially hydrogenated styrene / butadiene block copolymer and crystalline polypropylene, impact resilience,
Also, the elongation at break is large and the 300% modulus is small. Nevertheless, there is no big difference in tensile strength. This is considered to indicate that the amorphous polyolefin composition of the present invention is flexible at room temperature and has excellent performance as a rubber, as compared with the conventional polyolefin composition.

Further, from Example 4 and Comparative Example 4, an adhesive composition using the amorphous polyolefin composition of the present invention (Example 4) was prepared from a conventional polyolefin composition (Comparative Example 4). It has a longer open time than that of) and is suitable for adhesion of biaxially oriented polypropylene film and the like.

[Effect of the present invention] The amorphous polyolefin composition of the present invention is not only excellent in heat resistance and weather resistance, but also in terms of rubber performance, mechanical strength, flexibility, etc., aromatic vinyl-conjugated diene block. Not inferior to the partially hydrogenated products of the copolymer. But the price is much cheaper.

Therefore, it can be suitably used in a wide range of fields such as adhesive compositions such as outdoor sealants, adhesives and pressure-sensitive adhesives, and molding materials.

Further, since the amorphous polyolefin composition of the present invention has excellent fluidity, an adhesive composition prepared by blending a tackifier or the like is easy to apply to the adhesive surface and has a long open time.

Therefore, it is suitable for adhesion of polypropylene film and the like.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location C09J 201/00 JBC

Claims (5)

[Claims] 1. An amorphous polyolefin polymer having a number average molecular weight of 1000 to 20,000 (3 to 80% by weight), and (b) a partial hydrogenated product of an aromatic vinyl / conjugated diene block copolymer (97). ˜20% by weight, an amorphous polyolefin composition. 2. An amorphous polyolefin polymer is (a) a propylene homopolymer, or (b) a propylene content of 40% by weight or more, a random copolymerization of propylene and ethylene and / or α-olefins. The amorphous polyolefin composition according to claim 1, wherein the amorphous polyolefin composition is a coalesced product, which is not a by-product but is a product produced for the purpose. 3. The amorphous polyolefin composition according to claim 2, wherein the propylene / ethylene random copolymer has an ethylene content in the range of 8 to 30% by weight. 4. The amorphous polyolefin composition according to claim 2, wherein the propylene / 1-butene random copolymer has a 1-butene content of 10 to 60% by weight. 5. Amorphous polyolefin composition according to claim 1, 100 parts by weight (b) Tackifier: 20 to 500 parts by weight (c) Resin (tackifier (Excluding the resin used as)
An adhesive composition comprising 0 to 300 parts by weight.