JPH07216187A - Transparent high-strength resin composition - Google Patents

Abstract

PURPOSE:To obtain a high-strength resin composition markedly improved in impact resistance without detriment to transparency by mixing a specified clock copolymer with a specified vinylaromatic hydrocarbon resin. CONSTITUTION:This resin composition comprises a block copolymer (I) composed of terminal block A1 and A2 derived from a vinylaromatic hydrocarbon polymer and being different in size and middle blocks B1 and B2 derived from a conjugated diene monomer polymer and/or a conjugated diene monomer/ vinylaromatic hydrocarbon copolymer and having a vinylaromatic hydrocarbon/ conjugated diene monomer weight ratio of 50/50 to 90/10, and (II) at least a polymer of a vinylaromatic hydrocarbon and/or a copolymer of a vinylaromatic hydrocarbon with a (meth)acrylate.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention provides a block copolymer and a vinyl aromatic hydrocarbon resin which are highly transparent and have excellent impact resistance and which are composed of a polymer of a vinyl aromatic hydrocarbon and a conjugated diene monomer. The present invention relates to a transparent high strength resin composition containing.

[0002]

2. Description of the Related Art When a vinyl aromatic hydrocarbon and a conjugated diene monomer are block-copolymerized by a living anionic polymerization with an organic lithium compound as an initiator in an organic solvent, the composition ratio of the vinyl aromatic hydrocarbon and the conjugated diene monomer is Polymers with various physical properties can be obtained due to the difference in the structure of the block copolymer, and when the content of the polymer of the conjugated diene monomer is large, it shows the characteristics of the thermoplastic elastomer, and the content of the polymer of vinyl aromatic hydrocarbon is contained. Higher amounts exhibit the properties of thermoplastics. On the other hand, in these block copolymers, the abundance of the conjugated diene polymer affects the impact resistance, and the conjugated diene polymer has a high degree of transparency because it is dispersed below the wavelength of visible light. However, it is used as a reinforcing agent because of its excellent physical property balance and compatibility with various vinyl aromatic hydrocarbon polymers (Japanese Patent Publication Nos. 45-19388 and 47-47).
43618, Japanese Patent Publication No. 53-417, etc.).

However, although the above resin composition has good transparency, since the conjugated diene polymer in the block copolymer used is finely dispersed, its absorbency against impact is small and its impact resistance is insufficient. It was As a method for improving the impact resistance, there are methods such as increasing the molecular weight of the block copolymer to be blended and increasing the content of the conjugated diene. Not obtained. As another method, there has been proposed a method of improving impact resistance by providing a portion in which a vinyl aromatic hydrocarbon and a conjugated diene monomer are randomly copolymerized in a block copolymer to be blended (JP-A-48). -48546, Japanese Patent Publication No. 53-416, etc.),
With these resin compositions, the impact resistance is improved, but the transparency is lowered, and a resin having good transparency and impact resistance has not been obtained.

[0004]

SUMMARY OF THE INVENTION In view of the above situation, an object of the present invention is to develop a resin composition whose transparency is improved and whose impact resistance is greatly improved.

[0005]

DISCLOSURE OF THE INVENTION The inventors of the present invention have found that the structure of a block copolymer to be blended, in particular, a polymer portion of a conjugated diene monomer and a portion where a vinyl aromatic hydrocarbon and a conjugated diene monomer are randomly copolymerized. As a result of diligent research on the placement of the resin, it was found that a resin composition having significantly improved impact resistance while maintaining good transparency can be obtained as compared with a resin produced by a conventional technique. Came to.

That is, the present invention is a vinyl aromatic hydrocarbon.
Block copolymer of vinyl and conjugated diene monomer and vinyl aroma
In a resin composition containing a group hydrocarbon resin, the block copolymer (I) has different sizes at both ends.
Vinyl aromatic hydrocarbon block A₁And A₂Have
The polymer and / or copolymer of the conjugated diene monomer is contained in the middle portion.
Copolymer of diene monomer and vinyl aromatic hydrocarbon
Rock B₁And B ₂Having (1) vinyl aromatic hydrocarbon water
Weight ratio of elementary / conjugated diene monomer is 50/50 to 90 /
10) and is included in the block copolymer (2).
The block ratio of the vinyl aromatic hydrocarbon polymer contained is 2
5 to 90% by weight (however, block rate (%) = (W
/ W₀) × 100, W = vinyl content in the block copolymer
Weight of aromatic hydrocarbon polymer block, W₀= Block
It is the total weight of vinyl aromatic hydrocarbon polymer in the polymer.
), (3) Block A₁ And A₂ Between the number average molecular weights of
0.1 ≦ MN₁/ MN₂The relation of ≦ 0.8 is established (however,
MN₁= Block A ₁ Number average molecular weight, MN₂=
Lock A₂ Number average molecular weight), (4) Block B
₁ And B₂ At 1.2 ≦ M₁/ M₂≤10 relationship
Is satisfied (however, M₁= Block B₁ Conjugated diene
Nomer polymer weight fraction, M₂= Block B₂ Inside
It is the weight fraction of the polymer of the role diene monomer), (5)
The structure of the block copolymer is (a) A₁-B₁-B₂−
A₂Or (b) (A₁-B₁-B₂-A₂)_n-X
(However, X is a residue of a polyfunctional coupling agent or a polyfunctional coupling agent.
(Representing the residue of an organolithium compound), and (6) number flat
Characteristic that the average molecular weight is 40,000-500000
(II) vinyl aromatic hydrocarbon resin is vinyl aromatic
One or more hydrocarbon polymers and / or vinyl
Copolymerization of aromatic hydrocarbons and (meth) acrylic acid esters
The present invention relates to a resin composition which is a united body.

The present invention will be described in detail below. As the vinyl aromatic hydrocarbon used in the block copolymer in the present invention, styrene, o-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 1,3-
There are dimethylstyrene, α-methylstyrene, vinylnaphthalene, vinylanthracene and the like, but styrene is particularly common.

The conjugated diene monomer used for the block copolymer in the present invention is 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene. , 1,3
-Pentadiene, 1,3-hexadiene and the like, but particularly common ones include 1,3-butadiene and isoprene.

Blocks A ₁ and A in the block copolymer
_{Although 2} is obtained by polymerizing the vinyl aromatic hydrocarbon, it may be a polymer block composed of a single vinyl aromatic hydrocarbon or a copolymer block composed of a plurality of vinyl aromatic hydrocarbons. .

Blocks B ₁ and B ₂ are one or two of the above vinyl aromatic hydrocarbon and conjugated diene monomer, respectively.
Obtained by polymerizing one or more species.

The weight ratio of vinyl aromatic hydrocarbon / conjugated diene monomer for producing the block copolymer (I) is 50/50 to 90/10, preferably 60/4.
It is 0 to 85/15. When this weight ratio is less than 50/50, transparency is lowered, and when it exceeds 90/10, impact resistance is lowered, which is not preferable.

The block ratio of the vinyl aromatic hydrocarbon polymer contained in the block copolymer used in the present invention is 25 to 90%, preferably 50 to 85%. If the block rate is less than 25%, the transparency is significantly lowered, and if it exceeds 90%, the impact resistance is lowered, which is not preferable. The block ratio of the vinyl aromatic hydrocarbon polymer is the block ratio (%) = (W × W ₀ ) × 100 (where W = the weight of the vinyl aromatic hydrocarbon polymer block in the block copolymer, W ₀ = indicates the total weight of the vinyl aromatic hydrocarbon polymer in the block copolymer).

Here, the total weight of the vinyl aromatic hydrocarbon polymer in the block copolymer is the weight of all the vinyl aromatic hydrocarbons subjected to the polymerization, and the weight of the vinyl aromatic hydrocarbon polymer block is Ozone decomposition of the block copolymer (Y. TANAKA, et al., RUBBER CHE
MISRY AND TECHNOLOGY, 58 ,
16 (1985)) GPC measurement of the obtained vinyl aromatic hydrocarbon polymer component (using an ultraviolet spectroscopic detector whose wavelength is set to 254 nm as a detector of GPC), the molecular weight corresponding to each peak is It was determined from a calibration curve prepared in advance using standard polystyrene and a styrene oligomer, and those having a number average molecular weight of more than 3000 were quantified and determined from their peak areas.

Between the number average molecular weights of the blocks A ₁ and A ₂ at both ends of the block copolymer used in the present invention, 0.1 ≦ MN ₁ / MN ₂ ≦ 0.8 (where MN ₁ = Number average molecular weight of block A ₁ , MN ₂
= Representing the number average molecular weight of block A ₂ ), and more preferably 0.1 or more and 0.6 or less. If this value exceeds 0.8 or less than 0.1, a sufficient balance between impact resistance and transparency cannot be obtained.

The number average molecular weight of the blocks A ₁ and A ₂ incorporated in the block copolymer is measured by GPC for a vinyl aromatic hydrocarbon polymer component obtained by ozonolysis of the block copolymer, Conventional method (for example, the method described in "Gel Permeation Chromatography" (published by Maruzen))
Is a value calculated according to. In addition, the calibration curve in GPC uses what was created using standard polystyrene.

The block B ₁ containing the polymer of the conjugated diene monomer in the block copolymer used in the present invention.
And between the conjugated diene monomer polymer _{B 2, 1.2 ≦ M 1 /} M 2 ≦ 10 ( provided that the weight of M ₁ = conjugated diene monomer polymer weight in the block B ₁ / blocks B _1, M ₂ = There is relationship between block B the weight of the conjugated diene monomer polymer weight / blocks B ₂ of _2), more preferred range is 1.4 to 5. If this value is less than 1.2 or exceeds 10, a sufficient balance between impact resistance and transparency cannot be obtained.

The weight ratio of the conjugated diene monomer polymer is also
High block B₁ Is a block with a small number average molecular weight
₁ In addition, a block with a low weight ratio of the conjugated diene monomer polymer is used.
B ₂ Is a block A with a large number average molecular weight₂ Adjacent to
The arrangement is preferred. That is, the structure of the block copolymer
Is (a) A₁-B₁-B₂-A₂, Or (b) (A₁
-B₁-B₂-A₂)_n-X is preferable (however,
X is a residue of a polyfunctional coupling agent or a polyfunctional organic
Indicates the residue of a lithium compound).

The distribution of the polymer of the vinyl aromatic hydrocarbon and the conjugated diene monomer in the blocks B ₁ and B ₂ is such that the vinyl aromatic hydrocarbon and the conjugated diene are evenly distributed and a minute block composed of the vinyl aromatic hydrocarbon. repetition of micro blocks composed of conjugated diene structure or the like conjugated diene distributed from block a ₁ to block a ₂ direction is gradually decreased, but also the effect of the present invention can be obtained in any case, block a ₁ especially desirable are the To A ₂ direction, the conjugated diene distribution gradually decreases.

Further, the entire block B ₁ is a polymer block of a conjugated diene monomer, or the block B ₁ adjacent to the block A ₁ side has a polymer block portion of a conjugated diene monomer at a position adjacent to the block A _1. It is desirable to have Even if the blocks B ₁ and B ₂ are clearly separated by a minute block of the vinyl aromatic hydrocarbon polymer and a step difference in the weight ratio of the conjugated diene monomer polymer,
Alternatively, the distribution of the conjugated diene monomer polymer may change continuously through the two blocks. The scope of the present invention is not limited by the above description.

The block copolymer used in the present invention may have a radial structure obtained by coupling a linear structure satisfying the conditions specified in the present invention with a polyfunctional coupling agent. Good. Examples of polyfunctional coupling agents used in this case include compounds having 2 to 4 functional groups such as silicon tetrachloride, epoxidized soybean oil, and organic carboxylic acid esters.

The number average molecular weight of the block copolymer is 40,000 to 500,000, preferably 80,000 to 3.
It is 00000. If it is less than 40,000, the thermal stability of the resin is lowered, which is not preferable, and if it exceeds 500,000, the workability is lowered and the characteristics of the present invention cannot be obtained.

The block copolymer used in the present invention can be produced by polymerizing a vinyl aromatic hydrocarbon and a conjugated diene monomer in an organic solvent using an organolithium compound as an initiator. Organic solvents include butane, pentane, hexane, isopentane, heptane, octane, aliphatic hydrocarbons such as isooctane, cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane, alicyclic hydrocarbons such as ethylcyclohexane, or benzene, toluene. Aromatic hydrocarbons such as ethylbenzene and xylene can be used.

The organic lithium compound is a compound in which one or more lithium atoms are bonded in the molecule, and examples thereof include ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium,
Tert-butyllithium, hexamethylenedilithium, butadienyldilithium, isoprenyldilithium and the like can be used.

The molecular weight of the block copolymer used in the present invention can be controlled by the concentration of the initiator with respect to the total amount of the monomers added. Further, the block ratio of the block copolymer can be controlled by the concentration of the randomizing agent when the vinyl aromatic hydrocarbon and the conjugated diene are copolymerized.

Tetrahydrofuran (THF) is mainly used as the randomizing agent, but other ethers, amines, thioethers, phosphoramides, alkylbenzene sulfonates, potassium or sodium alkoxides and the like can also be used. Suitable ethers include THF, dimethyl ether, diethyl ether,
Diphenyl ether, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether and the like can be mentioned. As the amines, tertiary amines such as trimethylamine, triethylamine, tetramethylethylenediamine, and cyclic tertiary amines can be used.
In addition, triphenylphosphine, hexamethylphosphoramide, potassium or sodium alkylbenzene sulfonate, potassium or sodium butoxide and the like can be used as the randomizing agent.

In addition, it is also possible to mechanically continuously feed the vinyl aromatic hydrocarbon and the conjugated diene monomer to the polymerization vessel, or alternately add the vinyl aromatic hydrocarbon and the conjugated diene monomer to the polymerization vessel little by little. The rate can be controlled.

Block B₁And block B₂Different types of
Is a vinyl aromatic hydrocarbon and conjugated diene
Add the monomers at the required ratio all at once or
Cook B ₁And block B₂The conjugate di corresponding to both regions of
After adding the en-monomer all at once, block B₁Minute vinyl
Of aromatic hydrocarbons
Rock B₁Block, and then block B₂Minutes of vinyl
With aromatic hydrocarbons and / or randomizer in bulk
Block B by adding₂To form a
However, no matter what manufacturing method,
If it corresponds to the structure, the effect will appear.

In the present invention, as the vinyl aromatic hydrocarbon resin, one kind of vinyl aromatic hydrocarbon homopolymer,
Alternatively, a copolymer of two or more kinds of vinyl aromatic hydrocarbons and / or a copolymer of vinyl aromatic hydrocarbons and (meth) acrylic acid ester is used.

As the vinyl aromatic hydrocarbon, those similar to those used in the above block copolymer can be used.

As the (meth) acrylic acid ester, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, hexyl acrylate, (2-ethyl) hexyl acrylate, methyl methacrylate,
Examples thereof include ethyl methacrylate, butyl methacrylate, (2-hydroxy) ethyl methacrylate and the like.

The vinyl aromatic hydrocarbon / (meth) acrylic acid ester copolymer used in the present invention has a vinyl aromatic hydrocarbon / (meth) acrylic acid ester weight ratio of 5/95 or more, It is preferably 40/60 or more, more preferably 70/30 or more, and is obtained by polymerizing a monomer mixture.

The weight ratio of the block copolymer of (I) / the vinyl aromatic hydrocarbon resin of (II) in the resin composition of the present invention is 20/80 to 95/5, preferably 30 /. 70-95 / 5, more preferably 40 /
It is 60 to 95/5. If the weight ratio of the block copolymer / vinyl aromatic hydrocarbon resin is less than 20/80, the impact resistance of the resin is insufficient, which is not preferable.

In order to effectively utilize the resin composition of the present invention in various fields, it is desirable to add various additives as necessary. As the additive, various stabilizers, lubricants, processing aids, antiblocking agents, antistatic agents, antifogging agents, light resistance improvers, softening agents, plasticizers, pigments and the like can be used.

As the stabilizer, 2,6-di-t-butyl-
Phenol-based antioxidants such as 4-methylphenol, phosphorus-based antioxidants such as trisnonylphenyl phosphite, and the like can be mentioned. Examples of antiblocking agents, antistatic agents, and lubricants include fatty acid amides, ethylene bisstearamide, sorbitan monostearate, saturated fatty acid esters of fatty acid alcohols, and pentaerythritol fatty acid esters. These additives are preferably used in the range of 5% by weight or less based on the resin.

The resin composition in the present invention can be obtained by mixing the block copolymer and the vinyl aromatic hydrocarbon resin, but the mixing method may be any known method, for example, in general It may be dry blended with a Henschel mixer, a ribbon blender, a super mixer, a V blender or the like, and may be melt mixed with an extruder.

[0036]

EXAMPLES The present invention will be described in detail below with reference to examples.

Example 1 n-butyllithium was used as an initiator in a cyclohexane solvent.
Then, using a monomer of styrene and butadiene,
A corresponding to P1₁-B₁-B₂-A₂Molded block
A copolymer was prepared. In the manufacture of block copolymers
Embedded in the block copolymer
Lock A₁And A₂The number average molecular weight ratio of
₁Amount of styrene used for parts and block A₂To use
Adjustment by changing the ratio of the styrene content.
Ren's block rate is Block B ₁And block B₂Department
Of styrene and butadiene added as a monomer of
It was adjusted by changing the ratio of the monomers. Obtained Bro
90 parts by weight of styrene copolymer and styrene resin (Electrochemical Industry
Made by the company, trade name Denka Styrol GP-1) 10 parts by weight
After mixing and pelletizing with an extruder, Nissei Plastic Industry Co., Ltd.
FS-55 (2oz injection molding machine) manufactured at 220 ° C
× width × thickness = 100 mm × 100 mm × 2 mm play
Was injection molded and used for physical property testing. Show the result
Shown in 2.

Examples 2-3, Comparative Example 1 The block copolymer P1 obtained in Example 1 was used, and Table 2 was used.
The properties were measured by mixing with styrene resin in the proportions shown in Tables 3 and 3, and the results are shown in the same table.

Examples 4 to 7 and Comparative Examples 2 to 6 P2 and P4 shown in Table 1 were polymerized in the same manner as in Example 1.
.About.P7 block copolymers were obtained. In addition, in Example 7, after the polymerization was completed, a block structure of (A _1- B ₁ -B ₂ -A ₂₎ to produce a block copolymer P3 represented by ₃ X. These block copolymers were mixed with styrene resin in the proportions shown in Tables 2 and 3 in the same manner as in Example 1, and the physical properties were measured. The results are shown in the same table.

Example 8 90 parts by weight of the block copolymer P1 and a copolymer resin of methyl methacrylate and styrene containing 22% by weight of methyl methacrylate (manufactured by Nippon Steel Chemical Co., Ltd., trade name Estyrene MS-
200. Hereinafter, 10 parts by weight of MS resin) is mixed and pelletized with an extruder, and then FS- manufactured by Nissei Plastic Co., Ltd.
55 (2oz injection molding machine) at 220 ° C, length x width x
A plate having a thickness of 100 mm × 100 mm × 2 mm was injection-molded and subjected to a physical property test. The results are shown in Table 4.

Examples 9 to 14 and Comparative Examples 7 to 12 The physical properties were measured in the same manner as in Example 8 with the formulations shown in Tables 4 and 5, and the results are shown in the same table.

Examples 15 to 21, Comparative Examples 13 to 18 Tables 6 and 7 show combinations of block copolymers and n-butyl acrylate-styrene copolymer resin containing 10% by weight of n-butyl acrylate. The physical properties were measured in the same manner as in Example 8 depending on the compounding, and the results are shown in the same table. As described above, as shown in Tables 2, 4 and 6, the resin composition of the present invention is suitable for producing a molded product having excellent transparency and impact resistance.

The physical properties in the table were measured by the following methods. (1) Drop weight strength: In the atmosphere of the above-mentioned plate at 20 ° C., a weight having a tip R of 10 m / mφ was dropped by changing the weight and the height, and the maximum height at which breakage did not occur was found. Displayed in height. (2) Haze: The above-mentioned plate was ASTM-D-1003.
It was measured by the method. (3) Hardness: ASTM-D-785 was applied to the above plate.
It was measured by the method of (Rockwell hardness: R scale). The condition of the plate used for measuring the falling weight strength and the cloudiness was adjusted at 23 ° C. × 50% × 24 hours after injection molding.

[0044]

[Table 1]

[0045]

[Table 2]

[0046]

[Table 3]

[0047]

[Table 4]

[0048]

[Table 5]

[0049]

[Table 6]

[0050]

[Table 7]

[0051]

Since the resin composition of the present invention is excellent in impact resistance and transparency, the resin composition is excellent in transparency,
A molded product with high impact resistance can be obtained. Further, not only molded products can be obtained by injection molding or injection hollow molding, but also molded into films / sheets by extrusion molding, inflation molding, etc., and can be used for various purposes as they are or by secondary processing such as vacuum pressure molding. . In particular, it is effective for use in a transparent sheet that requires a high degree of balance between transparency and impact resistance, and as a waist strength imparting component for a low temperature shrinkable shrink film.

Claims (1)

[Claims] 1. A block copolymer of the following (I) and (I)
Transparent high strength containing I) vinyl aromatic hydrocarbon resin
Degree resin composition. (I) Vinyl chloride having different sizes at both ends of the block copolymer
Aromatic hydrocarbon polymer block A₁And A₂Have
The polymer and / or copolymer of the conjugated diene monomer is contained in the middle portion.
Copolymer of diene monomer and vinyl aromatic hydrocarbon
Rock B₁And B ₂Having (1) vinyl aromatic hydrocarbon water
Weight ratio of elementary / conjugated diene monomer is 50/50 to 90 /
10) and is included in the block copolymer (2).
The block ratio of the vinyl aromatic hydrocarbon polymer contained is 2
5 to 90% by weight (however, block rate (%) = (W
/ W₀) × 100, W = vinyl content in the block copolymer
Weight of aromatic hydrocarbon polymer block, W₀= Block
It is the total weight of vinyl aromatic hydrocarbon polymer in the polymer.
), (3) Block A₁ And A₂ Between the number average molecular weights of
0.1 ≦ MN₁/ MN₂The relation of ≦ 0.8 is established (however,
MN₁= Block A ₁ Number average molecular weight, MN₂=
Lock A₂ Number average molecular weight), (4) Block B
₁ And B₂ At 1.2 ≦ M₁/ M₂≤10 relationship
Is satisfied (however, M₁= Block B₁ Conjugated diene
Nomer polymer weight fraction, M₂= Block B₂ Inside
It is the weight fraction of the polymer of the role diene monomer), (5)
The structure of the block copolymer is (a) A₁-B₁-B₂−
A₂Or (b) (A₁-B₁-B₂-A₂)_n-X
(However, X is a residue of a polyfunctional coupling agent or a polyfunctional coupling agent.
(Representing the residue of an organolithium compound), and (6) number flat
Characteristic that the average molecular weight is 40,000-500000
Block copolymer (II) containing one or more vinyl aromatic hydrocarbons
Combined and / or vinyl aromatic hydrocarbons and (meth) ac
Copolymer of phosphoric acid ester