JPS60223813A - Block copolymer and its production - Google Patents

Abstract

PURPOSE:A block copolymer excellent in impact resistance, regidity, low-temperature stretchability, and environmetal cracking resistance, prepared by adjoining polymer blocks of a vinylaromatic hydrocarbon and a conjugated diene of a specified composition and polymer blocks of a vinylaromatic hydrocarbon to each other. CONSTITUTION:A block copolymer having at least one polymer segment A comprising (a) 60-95wt% vinylaromatic hydrocarbon and (b) 40-5wt% conjugated diene and having a content of component (a) of 90-100wt%, at least one polymer segment B having a content of component (a) of 70-90wt%, and at least one polymer segment C having a content of component (a) of 0-75wt%, wherein the total amount (A') of the part corresponding to segment A is 20-80pts.wt., the total (B') of the part corresponding to segment B is 10pts.wt. or above, the total (C') of the part corresponding to segment C is 10pts.wt. or above, B'+C'= 20-80pts.wt., and A'+B'+C'=100pts.wt. and segment B is adjacent to segment A.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a block co-vehicle body having excellent impact resistance, rigidity, low-temperature stretchability, and environmental damage resistance, an O, and a method for manufacturing the same. .

[Prior Art] It has been known that block copolymers having various properties can be obtained by copolymerizing a vinyl aromatic hydrocarbon and a conjugated diene using an organolithium compound as a catalyst. In particular, in the case of block copolymer resins with a relatively high content of vinyl aromatic hydrocarbons, block copolymers ζ that are transparent and have excellent impact resistance can be obtained by selecting certain conditions. Recently, the amount of these products has been increasing in the field of food packaging containers. force)
As a method for producing a flock copolymer resin, for example (i.
No. 2, Special Publication No. 47-28915, Special Publication No. 48-410
6, Japanese Patent Publication No. 58-11446, etc. have been proposed. When the block copolymers obtained by these methods are stretched and used as a heat-shrinkable film, the shrinkage rate at low temperatures is low (
・There is a problem in that when articles such as glass bottles are coated with the heat-shrinkable film, cracks occur in the film, and an improvement is desired.

[Problems that the invention attempts to solve]

In order to improve impact resistance, stiffness, low-temperature stretchability, and environmental damage resistance, the present invention clarified the structure of a block copolymer required to improve these physical properties, and the various physical properties mentioned above were improved. A block copolymer and a method for producing the copolymer are obtained.

[Means and effects for solving the problems] The present invention provides that the weight ratio of vinyl aromatic hydrocarbon and conjugated tsene is 75/2.
By creating a structure in which a polymer segment having a ratio of more than 5 and less than or equal to 90/10 is present adjacent to a vinyl aromatic hydrocarbon polymer segment, the above problems can be solved and the scales discovered. be.

That is, the present invention provides at least one polymer segment 1-A with a vinyl aromatic hydrocarbon content of more than 90 l (%H%) and a vinyl aromatic hydrocarbon content of 75 l (%H%). beyond,
90 is also one piece, vinyl aromatic hydrocarbon content is 75% by weight
A block copolymer each having at least one polymer segment C as follows, and having an overall weight ratio of vinyl aromatic hydrocarbon to conjugated diene of 60/40 to 9515, wherein the block copolymer The total amount of the portion corresponding to segment l-A (p:) occupied during coalescence is 20 to 80 parts by weight, and the total amount of the portion corresponding to segment B (B') is 1
0 parts by weight or more, the total amount of the part corresponding to segment C is 10 parts by weight or more, the total amount of B' and C' is 20 to 80 parts by weight.
Parts by weight (A'-4-B'+c'-100 parts by weight)
The present invention relates to a block copolymer characterized in that segment B is present adjacent to segment A, and a method for producing the block copolymer.

Since the block copolymer of the present invention has excellent low-temperature stretchability, it can be easily uniaxially or biaxially stretched at low temperatures, resulting in a film with excellent low-temperature shrinkability. The heat-shrinkable film obtained from the block copolymer of the present invention has excellent shrinkability at low temperatures or in a short period of time even at high temperatures, so it can be used for packaging products that involve shrink-wrapping processes, such as raw materials. Q('
1; Suitable for packaging foodstuffs, plastic molded products, etc. The heat-shrinkable film described above has excellent impact resistance and can be used as a covering for objects that are likely to be broken into pieces when broken, such as glass bottles. Historically, the above-mentioned heat-shrinkable film has excellent environmental damage resistance, and is resistant to destruction even when articles coated with heat-shrinkable film are left in extremely hot or outdoor environments.・It has the following features.

Especially if the item to be coated is metal, porcelain, glass, or polyester resin! 1', lj properties, for example, thermal expansion coefficient, water absorption, etc., conventional heat-shrinkable films have poor environmental damage resistance after coating, and the film easily deteriorates. However, when using the heat-shrinkable film obtained from the block copolymer of the present invention, there is no such fading and it is resistant to being left in the natural environment for a long time. Therefore, the above-mentioned heat-shrinkable film takes advantage of this advantage.
It can be particularly suitably used as a label for containers composed of +4'-portion as shown below.

Furthermore, the block copolymer of the present invention can be used to make various molded products by injection molding or injection blow molding. Furthermore, films and sheets formed from the block copolymer of the present invention by methods such as extrusion molding and inflation molding can be used as they are. It can be used for various purposes.

The present invention will be explained in detail below.

The block copolymers of the present invention have a vinyl aromatic hydrocarbon content of at least 111 M and preferably 2 or more.
% by weight of the polymer Cefmen I-A, preferably from 92 to 100 %, more preferably 100 % by weight, and at least one vinyl aromatic hydrocarbon content of more than 75 % by weight and 90 % by weight. The polymer Cefmen I-B preferably has a content of more than 80% by weight and less than 87% by weight, and preferably less than 75% by weight of at least one vinyl aromatic hydrocarbon. is 60 to 0% by weight, more preferably 60 to 30% by weight of the polymer segment C (if the vinyl aromatic hydrocarbon content is % on the O side, the Q, (the combined segment is a conjugated diene homopolymer It is a block copolymer of a vinyl aromatic hydrocarbon and a conjugated diene, each having a segment (corresponding to the segment).

If the vinyl aromatic hydrocarbon content of Cefmen I-A is less than 90% by weight, it will have poor rigidity, and if the vinyl aromatic hydrocarbon content of Cefmen B is outside the above range, it will have low-temperature stretchability.
It is not preferred because it has poor environmental damage resistance. In addition, if the vinyl aromatic hydrocarbon content of segment C exceeds 75% by weight, the impact resistance will be poor. or 60/40 to 9515, preferably 65/35
~90/10. The amount of vinyl aromatic hydrocarbons is 60
If the nail weight is less than %, the rigidity will be poor (1:l), and if it exceeds 95 market weight, the impact resistance will be poor, which is not preferable. Further, the proportion of each segment in the block copolymer of the present invention is such that the total amount (A') of the portion corresponding to Cefmen) A is 20 to 80.
Parts by weight, preferably 30 to 70 parts by weight, Cefmen I-B
The total amount (B') of the parts corresponding to C is 10 parts by weight or more, preferably 1 part by weight.
5 to 55 parts by weight, the total amount of B' and C' is 20 to 80 parts by weight, preferably 30 to 70 parts by weight (however, A'+B'+C
'=100 parts by weight). If the ratio of A' or B'+C' deviates from the above range, the rigidity or impact resistance will be poor. In addition, when B' is less than 10% by weight, low-temperature stretchability,
Environmental damage resistance is poor, and if C' is less than 10% by weight, impact resistance is undesirable. Furthermore, the above-mentioned cefmen) B must exist adjacent to cefmen) A. When segment B is not adjacent to cement hA, low-temperature stretchability and environmental damage resistance are poor.

It could not have been foreseen from conventional knowledge that segment B would be extremely effective in imparting such performance.

In addition, in order to obtain a block copolymer with excellent environmental damage resistance, it is preferable that the blowing rate of the vinyl aromatic hydrocarbon in Cefmen) A exceeds 80% by weight, preferably 80% by weight or more. .

In the block copolymer of the present invention, segment B exhibits an effective effect in terms of low-temperature stretchability.
It is thought that this is because the force-lass transition temperature of segment A shifts to the lower temperature side due to the presence of . When the block copolymer is a styrene-butadiene block copolymer, the glass transition temperature due to the polystyrene block appears at about 906 C or higher when segment B is present at 1% or %; , below about 87°C, generally between about 60 and 85°C. Therefore, it can be confirmed that the block copolymer falls within the scope of the present invention by examining whether the glass transition temperature caused by the polystyrene block appears at about 87°C or lower. The glass transition temperature referred to here is the temperature determined from the inflection point of the dynamic elastic modulus (E') of dynamic viscoelasticity measured with a Yvlon (for example, Rheopyblon DDV-3 model manufactured by Toyo Baldwin). .

The structure of the block copolymer of the present invention is not particularly limited as long as the above-mentioned conditions are satisfied, but specific examples of block copolymers with particularly preferable structures include those with the following structure. can be mentioned.

(a) A-B-C (b) A-B-C-A (c) A-B-C-B-A (d) B-A-C-B-A (e) C-B-A -C-B-A (f) A=C-B-A-C-B-A (g) A--C-B-A-B-C-A ("In double, X is silicon tetrachloride , epoxidized soybean oil, a residue of a coupling agent such as an organic carboxylic acid ester, or a residue of an initiator such as a polyfunctional organolithium compound. n is an integer of 1 or more. Generally an integer of 1 to 5. ) The block copolymer of the present invention may be a mixture of two or more block copolymers with different structures that satisfy the conditions specified in the present invention. Furthermore, when segments A, B, or C include a copolymerized portion of a vinyl aromatic hydrocarbon and a conjugated diene, the distribution of the vinyl aromatic hydrocarbon in that portion may be uniform or tapered. Furthermore, segments A, B, or C may each contain two or more different polymers of vinyl aromatic hydrocarbons, which are included in the category of each segment. The number average molecular end of the block copolymer of the present invention is generally 30,000 to 500. +100, preferably 50,
000 to 350,000.

In the present invention, vinyl aromatic hydrocarbons include styrene, 0-methylstyrene, p-methylstyrene, p-t
ert-butylstyrene, 1,3-dimethylstyrene,
Examples include α-methylstyrene, vinylnaphthalene, and hinyl anthracene, and a particularly common example is styrene. This 1-7+Ti city/7'l2ZJmepAf9317Nμa=! A+--r id;l:l''+
ri, good. The conjugated diene is a diolefin having a pair of conjugated double bonds, such as 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene).
, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, etc., and particularly common ones include 1,3-butadiene and isoprene. These may be used not only alone, but also as a mixture of two or more.

The block copolymer of the present invention can be obtained by polymerization in a hydrocarbon solvent using an organolithium compound as an initiator.

Hydrocarbon solvents include aliphatic hydrocarbons such as butane, pentane, hexane, impentane, heptane, octane, and isooctane, alicyclic hydrocarbons such as cyclopentane, methylcyclopentane, cyclohexane, methylcyclohexane, and ethylcyclohexane, or benzene. , aromatic hydrocarbons such as toluene, ethylbenzene, and xylene. Organolithium compounds are organic monolithium compounds in which one or more lithium atoms are bonded in the molecule, such as edyllithium, n-propyllithium, isopropyllithium, n-butyllithium, 5ec.
Examples include -butyllithium, tert-butyllithium, hexamethylene dilithium, butadienyldilithium, and imprenyldilithium. The organolithium compound may be added in its entirety before polymerization, or may be added in portions during polymerization.

In the production of the block copolymer of the present invention, the charged monomer composition for forming each segment is such that monomers having a composition within the vinyl aromatic hydrocarbon content range corresponding to each polymer segment are used. Ru.

That is, in forming segment A, the volume ratio of vinyl aromatic hydrocarbon to conjugated diene is 90/1.0M,
',,1. OO/0 range of 7 ma-, Sefumen 1
- In the formation of segment B, the monomer ratio of vinyl aromatic hydrocarbon and conjugated diene is 75/25 (E, 90/) or less; in the formation of segment C, vinyl aromatic hydrocarbon The vehicle volume ratio of the conjugate diene is 75/
25 or less, monomers in the range of 0/100 are used. In addition, the amount of monomers charged for forming each segment is within the range of A' above as the total amount of monomers for forming Cefmen A in the formation of Cefmen I-A, and within the range of A' as the total amount of monomers for forming Cefmen) A, and within the range of seven monomers for forming segment B in the formation of Cefmen) H. - is within the range of B' above, and in the formation of segment C, the total amount of monomers for forming segment C is within the range of C'. There are no particular restrictions on the method of feeding the monomers for forming Cefmen A and C into the polymerization system, and they may be fed continuously into the polymerization system, the monomers may be fed all at once, or the monomers may be fed all at once. The portion may be supplied in several portions.

On the other hand, the monomer for forming segment B is obtained by continuously supplying a mixture of a vinyl aromatic hydrocarbon and a conjugated diene in the above composition ratio to a (+) polymerization system and polymerizing it.
or (11) 0.00 per 100 parts by weight of all monomers charged
It is polymerized in the presence of 1 to 10 parts by weight, preferably 0.01 to 5 parts by weight, of a polar compound or a lantamizing agent, and is formed adjacent to Cefmen I-A. In forming segment B, under the conditions (11) above, (1)
When the seven-mer supply method described in ) is not used, the monomer may be fed at once, or a portion of the seven-mer may be fed in several portions. In addition, when a mixture of a vinyl aromatic hydrocarbon and a conjugated diene is supplied to a polymerization thread for polymerization, the supply form of the vinyl aromatic hydrocarbon and the conjugated diene is that the vinyl aromatic hydrocarbon and the conjugated diene are copolymerized and the main Any method may be used as long as it forms a cell membrane (B) that satisfies the requirements stipulated in the invention. For example, the vinyl aromatic hydrocarbon and the conjugated diene may be combined in advance and the mixture may be fed to the lJj system, or the vinyl aromatic hydrocarbon and the conjugated diene may be fed through separate feed ports. While supplying to the polymerization system, these monomers may be mixed and copolymerized at the same time within the polymerization system, or one monomer may be completely supplied into the polymerization system and then the polymerization of that monomer is completed. Until then, the other heptamine may be fed into the polymerization system for copolymerization.

In the production of the block polymer of the present invention, ethers, amines, thioethers, phosphoramides, alkylbenzene sulfonates, potassium or sodium alkoxides, etc. can be used as polar compounds and randomizing agents. Examples of suitable ethers are dimethyl ether, diethyl ether, diphenyl ether and tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether.

As the amines, in addition to tertiary amines such as trimethylamine, triethylamine, and tetramethylethylenecyamine, cyclic tertiary amines can also be used. Phosphines and phosphoramides include triphenylphosphine and hexamethylphosphoramide. Randomizing agents include alkylbenzene sulfones, potassium or sodium acids, potassium or sodium butoxide, and the like. These polar compounds or randomizing agents may be added before the start of the polymerization reaction, or may be added before the polymerization of the segment 8 portion. The above requirements in the formation of segment B are extremely undesirable in imparting low temperature stretchability and environmental damage resistance to the block copolymer.

The polymerization humidity when producing the block copolymer of the present invention is generally -40°C to 150°C, preferably 40°C to 120°C. The time required for polymerization varies depending on the conditions, but is usually within 48 hours, particularly preferably 1 to 10 hours.

Further, it is desirable to replace the atmosphere of the 11 compound system with an inert gas such as nitrogen gas. The polymerization pressure is not particularly limited, and may be within a pressure range sufficient to maintain the monomer and solvent in a liquid phase within the humidity range. Care must be taken to avoid contamination of the reaction system with impurities such as water, oxygen, carbon dioxide, etc. that would inactivate the catalyst and living polymer.

The flocs obtained in this way (combined pasting polymers are 111% of water, alcohols, carbon dioxide, etc.)
Sufficient 7'J to inactivate the active terminus
It is inactivated by adding a certain amount.

At this time, by appropriately selecting a polymerization terminator such as reacting with carbon dioxide, alkylene oxide, alkylene sulfide, etc., terminals such as -OH, -5H
, -COOH, -COCl, -8O3H.

Block copolymers having various functional groups such as -CmiN at their ends can be obtained. If necessary, various stabilizers can be added to the block copolymer for the purpose of improving heat resistance, weather resistance, etc.

Methods for recovering the block copolymer from the obtained block copolymer solution include, for example, recovering the block copolymer by precipitation using a precipitating agent such as methanol, and heating the solution to evaporate the solvent. Any conventionally known method such as a method of recovering the copolymer by dispersing the copolymer solution in water, blowing in water vapor, and distilling off the solvent by heating. Can be adopted.

The block copolymer of the present invention includes a block copolymer resin of a vinyl aromatic hydrocarbon and a co-synthetic diene having a vinyl aromatic hydrocarbon content of 60 to 95 @ outside the range specified in the present invention; A block copolymer elastomer of a vinyl aromatic hydrocarbon and a conjugated diene having a vinyl aromatic hydrocarbon content of less than 60% by weight; Vinyl aromatic hydrocarbon yarn monomers and other vinyl monomers, such as ethylene, propylene, butylene, vinyl chloride, vinylidene chloride, vinyl acetate, acrylic esters such as methyl acrylate, methacrylic esters such as methyl methacrylate, At least one selected from copolymers with acrylonitrile, etc., comb-modified impact-resistant styrene resins (HIPS), etc.
Rigidity, impact resistance, etc. can be improved by blending with other polymers.

Additives can be added to the block copolymer of the present invention depending on the purpose. A suitable additive is 30
City F7J: Examples include softeners and plasticizers such as coumaron-indene resin, terpene resin, and oil. Further, various stabilizers, pigments, antiblocking agents, antistatic agents, lubricants, etc. can also be added. In addition, as an anti-blocking agent, lubricant, and antistatic agent, for example, fat 1 tube Amai F1
Ethylene bisstearamide, sorbitan monostearate 1, saturated aliphatic esters of aliphatic alcohols, pentaerythritol fatty acid esters, etc., and as ultraviolet absorbers, pt-butylphenyl salicylate, 2-(
2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3'-1-butyl-gi-methylphenyl)-5-chlorobenzotriazole, 2,5-his-[5' Compounds such as -t-butylbenzoxazolyl-(2)]thiophene described in "Practical Handbook of Refrigerating Additives for Plastics and Rubber" (Kagaku Kogyo Co., Ltd.) can be used. These are generally used in a range of 0.01 to 5% by weight, preferably 0.1 to 2% by weight.

The block copolymer of the present invention is transparent and has strong impact resistance, and can be used as a molding element for various molded products. That is, the block copolymer of the present invention can be used as it is or after being colored and processed into extrusion molded products such as sheets and films by the same processing means as ordinary thermoplastic resins, and thermoformed by vacuum or compressed air. Molding,
Specifically, food container parent device; 'W, blister packaging material,
It can be used in a wide range of containers and packaging materials, such as packaging films for fruits and vegetables and confectionery. In addition, it can be used in the fields of toys, daily necessities, food packaging containers, trinkets, and removable parts made by injection molding, blow molding, etc., and other applications in which general-purpose thermoplastic resins are used.13 It is particularly preferable. In terms of usage, after printing characters and designs on the uniaxially stretched film of the block copolymer defined in the present invention, it is tightly attached to the surface of the packaged object such as Plus Deck molded products, metal products, glass containers, porcelain, etc. by heat shrinkage. For example, it can be used as a so-called heat-shrinkable shell. In particular, the uniaxially stretched heat-shrinkable film obtained from the block copolymer of the present invention has excellent shrinkage characteristics and environmental damage resistance, so it has excellent shrinkage properties and environmental damage resistance, so it has excellent heat-shrinkability for plastic molded products that deform when heated to high temperatures. In addition to the label, materials such as metals, porcelain, glass, paper, polyolefin resins such as polyethylene, polypropylene, and polybutene, polyethylene, etc. Heat-shrinkable labels for containers using at least one member selected from methacrylic acid ester resins, polycarbonate thread resins, polyethylene terephthalate, polyester thread resins such as polyethylene terephthalate, and polyamide resins. It can be suitably used as a moon. In addition, the materials constituting the plastic container that can be used with the heat-shrinkable block copolymer film of the present invention include:
In addition to the above resins, polystyrene, comb-modified high impact polystyrene (HIPS), styrene-acrylonitrile copolymer, styrene-maleic anhydride copolymer, acrylonitrile-butadiene-styrene copolymer (ABS)
, methacrylic acid ester-butadiene-styrene co-k
(1t-(MBs).

Polyvinyl chloride resin, polyvinylidene chloride tree 11
Examples include 7z/-le resin, urea 1til BM, melamine resin, epoxy resin, unsaturated polyester resin, and silicone resin. These plastic containers may be a mixture of two or more resins or may be a laminate.

〔Effect of the invention〕

The block copolymer of the present invention has excellent low-temperature stretchability, is easy to stretch, has excellent low-temperature shrinkage, and has high elasticity. It can be made into a film that shows excellent shrinkability in a short period of time, even if it is a product.It has good rigidity, so it can be used particularly well for applications such as labels for various containers.It also has excellent impact resistance, so it will not break into pieces when broken. It is suitable for coating items that are easily blown away, and has excellent environmental damage resistance, so it can be used even when left in the natural environment for long periods of time.
It can be controlled.

Further, the block copolymer of the present invention can be made into various molded products, films, or sorts by methods such as injection molding, injection blow molding, extrusion molding, and inflation molding.

According to the production method of the present invention, it is possible to easily obtain a block copolymer.

〔Example〕

EXAMPLES The present invention will be described in more detail with reference to Examples below, but it goes without saying that the scope of the present invention is not limited thereto.

Examples 1 to 7 and Comparative Examples 1 to 8 Block copolymers having a polymer structure represented by the general formula A-E-C-E-A were produced using n-butyllithium as a catalyst in a cyclohexane solvent.

125 parts by weight of cyclohexane was charged into a stainless steel polymerization vessel equipped with a stirrer whose interior was replaced with nitrogen gas, and the internal temperature was brought to about 7.
After setting the temperature to 0° C., 0.05 parts by weight of n-butyllithium was added, and a cyclohexane solution containing 23 parts by weight of styrene was continuously supplied using a metering pump over 30 minutes for polymerization. The temperature within the polymerization system was then maintained at approximately 70°C for 10 minutes to substantially completely polymerize the monomers. Next, a cyclohexane solution containing 12.5 parts by weight of styrene and 3 parts by weight of butadiene was continuously supplied using a metering pump over 20 minutes to cause polymerization. Thereafter, the temperature in the polymerization system was maintained at about 70° C. for 10 minutes to substantially completely polymerize the monomer. Next, a cyclohexane solution containing 9 parts by weight of styrene and 14 parts by weight of butadiene was continuously supplied using a metering pump over 30 minutes, and the temperature inside the polymerization system was maintained at approximately 70°C for 10 minutes after the supply was finished. The monomer was substantially completely polymerized. Furthermore, a cyclohexane solution containing 125 parts of styrene and 3 parts of butadiene was continuously supplied using a metering pump over 20 minutes, and after the supply was finished, the temperature in the mixing system was maintained at approximately 70°C for 10 minutes. The monomers were essentially completely incorporated. Finally, a cyclohexane solution containing 23 parts of styrene was continuously supplied using a metering pump over 30 minutes, and after the supply was finished, the humidity in the mixing system was maintained at approximately 70°C for 10 minutes to substantially remove the monomer. Completely agreed. Thereafter, 2 parts of methanol was added to the polymerization solution to stop the combination, and then 0.5 parts of each of 2,6-tert-butyl-4-methylphenol and trisnonylphenyl phosphite were added as stabilizers. did. (The polymer number of the obtained block copolymer is assumed to be ■.) By the same method as above and according to the treatment shown in Table 1, the polymer structure is A-B-C-B-A, A-0- B-A, and A-C-A
A block copolymer represented by the general formula -C-A was produced. The amount of catalyst was adjusted so that the melt flow index (according to JIS K 6870, G condition) of the finally obtained block copolymer was about 5. (The polymer numbers of the obtained block copolymers are from ■ to 0.) Next, the monomers used in each polymerization step were prepared according to the treatment shown in Table 2 using n-butyllithium as a catalyst in a cyclohexane solvent. The entire amount is fed into the polymerization vessel at once for each polymerization step, and the polymer structure is changed to A-C! Block copolymers represented by the general formulas -B-A and (A-B-0 square S1) were produced.The block copolymer [phase] - 1/4 mole of 5iC1 relative to butyllithium
4 was added and a coupling reaction was performed. (The polymer number of the obtained block copolymer is 0 to
Let it be [phase]. ) Next, the block copolymer or block copolymer composition was molded into a sheet with a thickness of 0.25 mm at 200°C using a 40 mmψ extruder according to the formulations in Tables 3 and 4, Thereafter, the block copolymer was stretched 5 times and the block copolymer composition was uniaxially stretched horizontally in a tenter to produce a film having a thickness of approximately 50 μm to 60 μm. At this time, the temperature in the tenter was set to the lowest temperature at which a uniaxially stretched film could be stably produced from each block copolymer without breaking during stretching.

Next, the tensile modulus of the film of each block copolymer and block copolymer composition in the stretching direction, the bunture strength, and the heat shrinkage rate at 80° C. in the stretching direction were measured. As a result, it was revealed that the film obtained from the block copolymer of the present invention exhibits good stiffness, impact resistance, and shrinkage rate. Incidentally, all of these films had a heat shrinkage rate of less than 5% at 80°C in the direction orthogonal to the stretching direction. Moreover, all of them were transparent films.

Next, after printing letters and patterns on the film of each block copolymer and block copolymer composition obtained as above, a cylindrical heat-shrinkable label is formed with the stretching direction in the circumferential direction. 1 It was placed on a glass bottle using an automatic Nyurin label machine, and passed through a shrink tunnel controlled at a humidity of about 180'C to be heat-shrinked.

The passage time through the shrink tunnel was controlled so that each heat-shrinkable label was in tight contact with the surface of the glass bottle, but the lower the heat shrinkage rate at 180°C, the longer it took.

The films of Comparative Examples 5 and 8 had low rigidity, and good coated products could not be obtained.

In this way, we investigated the environmental damage resistance of glass bottle coating products made of films obtained from block copolymers.
All coated films obtained from the block copolymers of the present invention had good performance.

(Note 21) Based on JIS K-6732 (Note 3)
Based on JIS P-8134 (Note 4) A stretched film was immersed in silicone oil at 80°C for 5 minutes, and calculated using the following formula.

t - t' Heat shrinkage rate (%) = × 100 t: Length before shrinkage t': Length after shrinkage Note 5) Place the heat-shrinkable label-covered product outdoors in a natural environment.
The coated film was left to stand for a week and observed whether microcracks or cracks were formed in the coated film.

○: No microcracks or cracks are observed.

×: Microcracks and/or cracks are observed.

(Note 6) See Table 5 for the types of polymers used to produce the block copolymer composition.

Table 5 (Note 7) Sb indicates a polystyrene block, Bb indicates a polybutadiene block or a co-combination block of styrene and butadiene with a styrene content of 50 wt% or less.

Example 8 ~ Injection or S using 1O block co-assembly
Produce the shaped product, produce the obtained molded product, and
Table 6 (Note 8) Based on ASTM D 790 (Note 9)
Based on JIS K-7110 (Note 10) JIS
Conforms to K-7202 (Note II) JIS K-5
Based on JIS K-6714 (Note 12) Based on JIS K-6714 Example 11 Block copolymer [phase], [phase] and the same block copolymer composition as in Example 3.6 were used to produce 200 mm by using a 40 mmφ extruder. Each sheet with a thickness of 12 mm was produced at
A cylindrical dragon cup was molded.

Each of the resulting cup-shaped molded products was filled with 50 ml of water and allowed to fall naturally onto a concrete surface from a height of 1 m, but the cups did not break. Continuation of the amendment Written by Michibe Uga, Commissioner of the Patent Office, July 16, 1985 1. Patent Application No. 1987-79336 2. Title of the invention: block copolymer and its manufacturing method 3. Person making the amendment Relationship to the case / Patent applicant 1-2-6 Dojimahama, Kita-ku, Osaka-shi, Osaka (003) Asahi Kasei Industries, Ltd. President and Representative Director Makoto Furu 4, Agent 1-4-1 Yurakucho, Chiyoda-ku, Tokyo Sanshin Building Room 204 Telephone 501-21385, "Detailed Description of the Invention" column 6 of the specification to be amended, Contents of the amendment (1) [Environmental damage resistance] on page 3 of the specification, lines 17 to 18 "Excellent in environmental damage resistance and blow moldability" should be corrected to "Excellent in environmental damage resistance and blow moldability."

(2) Insert the following sentence between lines 7 and 8 on page 9 of the same book.

"Also, the block copolymer of the present invention has excellent blow moldability,
A blow molded product with good surface gloss and transparency can be obtained. In general, block copolymers have poor blow moldability, and during molding, the molten parison itself may develop shedding or a phenomenon of shark skin (surging or melt fracture).Furthermore, in order to improve these defects, melt flow has to be improved. If the height is increased, the molten parison tends to sag due to its own weight (called draw town), but the block copolymer of the present invention improves these problems. (3) In the same book, page 9, line 7 l, ``because of poor environmental damage resistance'' is corrected to ``because of poor environmental damage resistance and blow formability''.

(4) In the same book, page 1 O, line 7, add J to “destructiveness,”
It is corrected to "blow formability."

(5) In the same book, page 1O, line 12, “less destructive.”
Poor breakability and blow moldability. ” he corrected.

(6) "Injection blow molding" on page 25, line 11 of the same book is corrected to "blow molding."

(7) "It can be done." on page 25, line 13 of the same book.
Insert the following sentence after.

"In particular, the block copolymer of the present invention (because of its excellent blow moldability, extrusion blow method, injection blow method, injection/extrusion blow method, sheet/extrusion blow method, sheet blow method,
Various hollow molded products can be obtained by methods such as the cold parison method. (8) Add the following sentence below line 9 on page 38 of the same book.

Example 12 The same block copolymer or block copolymer composition used in Examples 1 to 6 was extruded into a molten parison using an extruder at a cylinder temperature of 200°C, and the parison was split into a mold. Cylindrical bottles with an average body wall thickness of 0.3 mm and an internal volume of 200 cc were molded in a mold. All of these bottles had no surface roughness and had good gloss and transparency.

For comparison, when cylindrical bottles were molded using block copolymers 8-1 and B-3 under the same molding conditions, the surfaces were shark-skin-like, lacked gloss, and had poor transparency. ”

Claims (1)

[Scope of Claims] (1) At least one polymer segment A with a vinyl aromatic hydrocarbon content exceeding 90% by weight, a vinyl aromatic hydrocarbon content exceeding 75 tonne weight, and a total of 90% by weight. (at least one f-combined Cefmen l-B,
Each has at least one polymer segment L-C with a vinyl aromatic hydrocarbon content of 75% by weight or less, and the overall weight ratio of vinyl aromatic hydrocarbon to conjugated diene is 60/40. - 9515, the total amount of the moieties corresponding to A in the block copolymer (Cefmen) (A+ or 20 to 80 Ichihaya-part, Cefmen) the total amount of the moieties corresponding to H (Cefmen) B') or 10 cities ii
5. Part I"2, total amount of part corresponding to Cefmen l-C (
C') is 10 Lili parts or more, the total of B' and C' is 20 to 80 Lili parts (However, A' Sat D'Sat/'-11
A block copolymer characterized in that B is present adjacent to segment A. (2) In a hydrocarbon solvent, using a lithium compound as an initiator, at least one polymer cefmen) A with a vinyl aromatic hydrocarbon content of more than 90% by weight, and a vinyl aromatic hydrocarbon content of 75% by weight % but not more than 90% by weight, and at least one polymer segment B having a vinyl aromatic hydrocarbon content of not more than 75% by weight, as a whole. In producing a block copolymer in which the weight ratio of vinyl aromatic hydrocarbon and conjugated diene is 60/40 to 9515, (a) the vinyl aromatic hydrocarbon content in the monomer charged for forming each segment; is within the range of vinyl aromatic hydrocarbon content corresponding to each of the above polymer segments, and (bl: Cefmen in total monomers charged) Total monomer yield of the portion corresponding to A (A'): 20 to 80 cities measurement department,
Segment B4 Kotoriki 1L and -F Otobe'? ) is 10 parts by weight or more, the total amount of monomers (C') in the portion corresponding to segment C is 10 parts by weight or more, and the total amount of B' and C' is 20 to 80 parts by weight ( However, 10B'+
(C'-100Lljfij part), (C) Segment I-B consists of (1) continuously supplying a mixture of vinyl aromatic hydrocarbon and conjugated diene in the above composition ratio to the polymerization system and polymerizing; /or (11) A total of 100 LKjjf monomers are cut into 1 part and polymerized in the presence of 0001 to 10 parts by weight of a polar compound or a randomizing agent, and the monomers are formed adjacent to segment A in the form of lJv. Method for producing block copolymers.