JPS588418B2 - block diagram - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to block copolymer latex composition coatings.

More specifically, the present invention relates to (A) an aqueous latex of a block copolymer consisting of a conjugated diolefin and a monovinyl-substituted aromatic compound obtained by a solution polymerization method, and (B) a rubber latex, a synthetic resin emulsion, or a mixture thereof. In a film obtained from a composition consisting of
The present invention relates to a film of the composition heat-treated under specific conditions.

The purpose of this invention is. The object of the present invention is to provide a film of the composition having excellent tensile properties, which can be obtained by heat-treating a dry film of the composition under specific conditions.

Synthetic rubber latex and synthetic resin emulsion are generally produced by emulsion polymerization, and it is clear that they are widely put into practical use without looking at examples such as styrene-butadiene copolymer latex and vinyl acetate polymer emulsion.

On the other hand, recent advances in polymerization technology have produced a number of unique solution-polymerized synthetic rubbers. Many attempts have been made to use this as latex.

The general method for producing latex from this type of solution-polymerized synthetic rubber is to add an emulsifier and water to a rubber polymerization solution or solid rubber dissolved in a suitable solvent, emulsify it, and then Stripping the solvent from the resulting emulsion. It is removed by flushing or the like.

moreover. The latex obtained in this way is so-called diluted latex, and can be used as is, but creaming is required if necessary. It can be concentrated by operations such as centrifugation.

One of the characteristic synthetic rubbers obtained by solution polymerization is a block copolymer in which conjugated diolefin polymer blocks A and monovinyl-substituted aromatic compound polymer blocks B are present alternately.

These are the general formulas A-B-A, (A-B)n, B-{A
-B)n, (A-B)-nA, or (A-B)mX
(However, A is a block substantially consisting of a novinyl-substituted aromatic compound polymer, and B is a block substantially consisting of a conjugated diolefin polymer. n is an integer from 2 to 10, and m is 3.
An integer of ~7, X is m polymer chains A-B bonded together.

It is a residue derived from a polyfunctional compound). It is called a thermoplastic elastomer and usually does not require crosslinking with sulfur compounds. Great strength and elongation similar to that of general vulcanized rubber. It exhibits low residual distortion characteristics.

The latex film of this block copolymer is a cast molded product made of mustard with its unique properties of high strength, high elongation, and high elasticity. Carpet sizing agents, fiber processing agents, surface coating agents, adhesives. It is useful as a paint binder, etc. Since it has the disadvantage of poor film-forming properties, it has been necessary to dry it at high temperatures in order to take advantage of its unique performance.

High strength achieved by forming the film at a temperature close to 95°C. Although a film with high elongation can be obtained, the film tends to contain air bubbles and must be carefully deposited, resulting in many disadvantages from the processing side.

It is possible to improve the film-forming properties of block copolymer latex by adding a rubber latex or synthetic resin emulsion that can form films at room temperature to the block copolymer latex, but in such cases. A drying temperature of 80°C or higher is required to develop the strength of the mixed film.
The same disadvantages as mentioned above arose.

The present inventor developed block copolymer latex and rubber latex. Synthetic resin emulsion. As a result of various studies on the strength development of a film obtained from a composition consisting of a composition containing the composition or a mixture thereof, it was found that a film formed by drying the composition at a temperature of 70°C or lower was not heated at 80°C or higher. At a temperature of , the product of the square of the temperature (in °C) and the time (in half) is
The present inventors have discovered that a film with significantly improved tensile properties can be obtained by heat treatment at a temperature and time such that the tensile strength is between 500,000 and 500,000.

The present invention consists of (A) a conjugated diolefin block and a monovinyl-substituted aromatic compound block obtained by a solution polymerization method, and has a molecular weight of 5,000 to 500,000 and a monovinyl-substituted aromatic compound content of 10 to 70% by weight. Aqueous latex containing at least one kind of polymer and CB) rubber latex, synthetic resin emulsion,
or a mixture of these. (A) in terms of solid content
In a film obtained from a composition containing 10 to 85% by weight of (B) and 90 to 15% by weight of (B). The film is formed by drying the composition at a temperature below 70°C. 80℃ or higher. At a temperature of 2 of the temperature (unit: °C)
The product of the power and time (unit: minutes) is io,ooo~500,
The block copolymer latex composition film is obtained by heat treatment at a temperature and time such that the block copolymer latex composition becomes 0.000%.

The block copolymer used in the present invention is a block copolymer in which monovinyl-substituted aromatic compound polymer block A and conjugated diolefin polymer block B exist alternately, and these have the general formula A-B-A, (A -B)n,B-(A
-B)-nA or (A-B)mX (where A is a block consisting essentially of a monovinyl-substituted aromatic compound polymer, B is a block consisting essentially of a conjugated diolefin polymer, n is an integer from 2 to 10) .m is an integer of 3 to 7, and X is a residue derived from a polyfunctional compound to which m polymer chains AB are bonded.

). these are. Polymerization can be carried out by living anionic polymerization using an alkali metal-based initiator.

Styrene is a monovinyl-substituted aromatic compound. o-
or p-vinyltoluene. Vinylxylene, ethylstyrene. Isopropylstyrene. tert-butylstyrene,
Examples include diethylstyrene and vinylnaphthalene, and mixtures of two or more of these can also be selected.

As the conjugated diolefin, 1,3-butadiene is used. 1,
3-pentadiene, isoprene. Examples include 2,3-dimethylbutadiene, and mixtures of two or more of these can be selected.

Preferred combinations are 1,3-butadiene and styrene and isoprene and styrene.

Such a block copolymer is prepared in the presence of the initiator.
A method in which monomers are sequentially polymerized block by block, a method in which two or more types of monomers with different copolymer reactivity ratios are simultaneously charged and polymerized to obtain a block copolymer, or a living polymerization method using the above-mentioned initiator. It can be obtained by a method of coupling block copolymers.

The block copolymer represented by (A-B)mX is.
It can be obtained by coupling a living block copolymer called A-BO with a polyfunctional coupling agent.

For example, a tetrafunctional coupling agent such as silicon tetrachloride can be used.

The molecular weight of the block copolymer is 5,000 to 500,00
0, and if the molecular weight is less than 5,000, it is difficult to obtain good tensile properties. If it exceeds 500,000, the solution viscosity becomes too high during emulsification. Emulsification becomes incomplete or difficult. This adversely affects the performance of the latex obtained.

The content of the monovinyl-substituted aromatic compound polymer block in the block copolymer can be selected within the range of 10 to 70% by weight based on the total polymer, and outside this range, it has characteristics as a thermoplastic elastomer. Poor and undesirable.

As the polymer solution for producing the block copolymer latex, the polymerization reaction solution may be used as it is. Alternatively, the solid rubber of the block copolymer may be mixed with benzene. toluene.
Xylene, cyclohexane, chloroform. Carbon tetrachloride. It may be used by dissolving it in a solvent such as trichlene or methane dichloride.

It is usually preferable to use the polymer solution at a concentration of 5 to 50% by weight.

The emulsifier used in producing the block copolymer latex is nonionic. It is a cationic or anionic type, and is 0.5 to 15 parts by weight based on 100 parts by weight of the block copolymer.
Weight part. It is preferably used in an amount of 1 to 8 parts by weight.

The reason why the amount of emulsifier is limited is. If it is less than 0.5 parts by weight, it is difficult to emulsify, and if it is more than 15 parts by weight, foaming becomes intense during the solvent removal operation, making the operation difficult, which is not preferable.

Examples of anionic emulsifiers include higher fatty acid salts, rosin salts,
Disproportionated stomate salts, higher alcohol sulfate ester salts.
Polyethylene glycol ether sulfate ester salts, amide bond (or ester bond) sulfate ester salts. Amide bond (or ether bond) sulfonate, alkylaryl sulfonate, ether bond (or ester bond. or amide bond) alkylallyl sulfonate.
At least one type of formalin-condensed naphthalene sulfonate salts, but is not limited thereto.

Specific examples of the anionic emulsifier include potassium oleate and sodium laurate. Sodium rosinate. Disproportionated potassium sulfate, sodium dodecylbenzenesulfonate, triethanolamine salt of dodecylbenzenesulfonate, sodium lauryl alcohol sulfate, ammonium mononaphthalenesulfonate, sodium oleoylmethyltaurate, sodium dioctylsulfosuccinate, dodecyl diphthalate Examples include sodium enyl ether disulfonate.

As a nonionic emulsifier. General formula R1-(O-R2)-
nOH, where R1 is an alkyl group having 8 to 18 carbon atoms, or an alkylphenyl group having 8 to 12 carbon atoms in the alkyl group. R2 is an alkylene group having 2 to 5 carbon atoms. n is an integer from 3 to 50); For example, polyoxyethylene nonyl phenyl ether.
Examples include polyoxyethylene lauryl ether, polyoxyethylene nonyl phenyl ether phosphate, and polyoxyethylene propylene nonyl phenyl ether phosphate.

Also. Nonionic emulsifiers other than the above general formula. for example. Sorbitan ester type (sorbitan monopalmitate, sorbitan monostearate, etc.), sorbitan ester ether W (polyoxyethylene sorbitan monostearate, etc.). Oxyethylene oxypropylene block polymers and the like may be used, but are not limited thereto.

These nonionic emulsifiers prevent the precipitation of latex particles during emulsification, solvent removal, and concentration when producing latex using the anionic emulsifier. It may be used in combination with the anionic emulsifier for the purpose of preventing coagulation and further improving the mechanical stability of the produced latex.

The cationic emulsifier is at least one of aliphatic amine salts, quaternary ammonium salts, alkylpyridinium salts, etc., but is not limited to these.

A specific example of a cationic emulsifier is octadecyltrimethylammonium chloride. Examples include alkyldimethylbenzylammonium chloride, polyoxyethylene alkylamine, octadecylamine acetate, and alkylisoquinolium bromide.

These cationic emulsifiers can be used in combination with nonionic emulsifiers.

Particularly suitable emulsifiers are higher fatty acid salts and rosin salts. Alternatively, it is a combination of a disproportionated sulfate salt and a nonionic emulsifier represented by the above general formula.

In the present invention, any known emulsifying machine may be used as long as it has a sufficiently strong emulsifying ability.

For example, homomixer. Homogenizer. There are disper mills and colloid mills. Two types of emulsifiers can be used in combination if necessary.

Next. Methods to remove the solvent in the emulsion and obtain dilute latex include distillation by heating in a jacket;
Known desolvation techniques can be used, such as steam distillation by blowing steam directly into the emulsion.

The dilute latex obtained in this way is usually 5 to 50%
It has a solid content concentration of approximately 100% by weight. This is a method to make concentrated latex with a higher solid content concentration. Creaming, centrifugation. Or there is water evaporation. In particular, concentration using a centrifuge is efficient and highly reproducible, making it a preferred method.

The rubber latex and synthetic resin emulsion used in the present invention are not limited as long as they have film-forming properties at room temperature.

Natural rubber latex is a rubber latex. Styrene-butadiene copolymer latex, methyl methacrylate-butadiene copolymer latex, acrylonitrile-butadiene copolymer latex. Butadiene polymer latex, isobrene polymer latex. Isobrene-isobutylene copolymer latex. Styrene-butadiene-vinylpyridine copolymer latex. Ethylene-propylene copolymer latex, ethylene-propylene-diene copolymer latex. Specific examples include chlorobrene polymer latex, which contains carboxyl groups. Alternatively, it may not be modified with a hydroxyl group or the like.

Examples of synthetic resin emulsions include acrylic acid ester emulsions, for example. Methyl acrylate polymer emulsion. Ethyl acrylate polymer emulsion. Acrylic ester polymer emulsions such as butyl acrylate polymer emulsions and 2-ethylhexyl acrylate polymer emulsions. Or copolymer emulsion 1 of acrylic esters such as ethyl acrylate-acrylic copolymer emulsion, butyl acrylate-mono-2-ethylhexyl acrylate copolymer emulsion, or acrylic ester-vinyl acetate copolymer emulsion, acrylic acid Specific examples include copolymer emulsions of an acrylic ester and at least one monomer copolymerizable, such as an ester styrene copolymer emulsion and an acrylic ester-methyl methacrylate copolymer emulsion. Also vinyl acetate emulsion.
for example. Vinyl acetate polymer emulsion, vinyl acetate-ethylene copolymer emulsion, vinyl acetate-ethylene-acrylic acid copolymer emulsion. Vinyl acetate-acrylic acid copolymer emulsion, vinyl acetate-maleic anhydride copolymer emulsion, vinyl acetate-maleic acid ester copolymer emulsion, vinyl acetate-ve
ova copolymer emulsion. Vinyl acetate-vinyl chloride copolymer emulsion. Specific examples include copolymer emulsions of vinyl acetate and at least one monomer copolymerizable with vinyl acetate, such as vinyl acetate-vinyl chloride-acrylic acid copolymer emulsions, and vinyl chloride polymer emulsions. Vinylidene chloride polymer emulsion, vinyl chloride-vinylidene chloride copolymer emulsion. Urethane polymer emulsion. Polyamide emulsion. Specific examples include polyester emulsions and the like.

A block copolymer latex and B rubber latex.
The mixing ratio of the synthetic resin emulsion or a mixture thereof is 10 to 85% by weight to 90 to 15% by weight in terms of solid content. Preferably 25-80% by weight vs. 75-20% by weight
It is.

The reason why it is limited to this range is that the block copolymer content is 1
This is because if it is less than 0% by weight, no effect will be seen even if the heat treatment is performed, and if it is more than 85% by weight, the film forming properties will be poor and undesirable.

The block copolymer latex composition is dried at a drying temperature of 70° C. or less to form a homogeneous continuous film.

The reason why the drying temperature is limited to 70° C. or lower is that if it is 70° C. or higher, air bubbles tend to enter, which is undesirable.

The block copolymer latex composition film obtained by the above method has a temperature of 80°C or higher, preferably 100°C or higher, and a temperature (unit: 2°C) squared and time (unit: 2 minutes).
The product of 10,000 to 500,000, preferably 15,
It is heat-treated at a temperature and time of 000 to 450,000 ℃.

The reason for limiting the temperature to 80℃ or higher is. This is because the effect of heat treatment does not appear below 80°C, and the reason why the product of temperature squared and time is limited to io,ooo ~ 500,000 is 10
,000 or less. The effect of heat treatment is not visible, 5
If it is more than 00,000, the composition film will undergo heat aging and the tensile properties will deteriorate, which is undesirable.

Any known heat treatment device may be used as long as it has a sufficiently strong heating capacity.

The composition forming the block copolymer latex composition film of the present invention includes: Preservatives, plasticizers. Antifoaming agent. Substances such as anti-setting agents, corrosion inhibitors, wetting agents and fillers can be included in conventionally used amounts.

Based on the following examples. Although the invention is described herein, they are not intended to limit the scope of the invention.

Example 1 Under nitrogen gas atmosphere. 1 mmol of n-butyllithium as active lithium was added to a 15% by weight n-hexane solution containing 33 g of a monomer mixture of 1,3-butadiene and styrene in a weight ratio of 40:60. After polymerization at 60°C for 4 hours, most of all monomers were copolymerized. Further to the formed active copolymer solution. 15 containing a monomer mixture 61 of 1,3-butadiene and styrene in a weight ratio of 70:30
A wt% n-hexane solution was added and polymerized at 70°C for 2 hours. After further polymerization at 85°C for 1 hour and almost all of the additional monomer was copolymerized, 1y of 2,6-di-tert-butyl-p-crepur was added as a stabilizer and the n-hexane solvent was removed by drying. A final block copolymer was obtained.

This copolymer contains 1,3% by weight of styrene.
-It is a thermoplastic elastomer made of butadiene and styrene. Its molecular weight is approximately 100,000.

per 100 parts by weight of a toluene solution (polymer concentration 10% by weight) of the block copolymer. 100% aqueous solution containing 5 parts by weight of sodium rosinate per 100 parts by weight of the block copolymer and 3 parts by weight of polyoxyethylene nonyl phenyl ether (average degree of polymerization of oxyethylene 15) per 100 parts by weight of the block copolymer. Mix the parts by weight. Emulsified with a disper mill.

The produced emulsion was immediately charged into a toluene removal tank equipped with a heating jacket and heated to evaporate and remove toluene.

At this time, some of the water evaporated together with toluene, resulting in a solid content of 135
A dilute latex with a concentration of % by weight was obtained.

This is continuously charged into a cylindrical centrifuge. Approximately 12,000
A concentrated latex with a solid content of 55% by weight was obtained by rotating.

The block copolymer latex and styrene-butadiene copolymer latex (Dow Latex DL612 manufactured by Asahi Dow Co., Ltd., solid content 48%) were 50:5 in terms of solid content.
The mixture was mixed in a ratio of 0 and 75:25, and a homogeneous dispersion was obtained by simple stirring.

A film with a thickness of 0.1 mm was created from the composition at room temperature (25°C), and the film was heat-treated at various temperatures and times using a hot air circulation dryer, and the tensile properties were measured.The results are shown in Comparative Examples. and are shown in Table 1.

Example 2 A concentrated Latinx was produced in the same manner as in Example 1 except that sodium dodecylbenzenesulfonate was used in place of the sodium rosinate used in Example 1 (solid content concentration 54% by weight).

The block copolymer latex and acrylic acid costel polymer emulsion (manufactured by Inu Nippon Ink Chemical Industry Co., Ltd.,
Boncoat R-3350 (solid content: 45%) was mixed at a ratio of 50:50 and 75:25 in terms of solid content, and a uniform dispersion was obtained by simple stirring.

The same operations as in Example 1 were carried out, and the results are shown in Table 2.

Example 3 Instead of the block copolymer made of styrene and 1,3-butadiene produced in Example 1, a radial teleblock copolymer made of styrene and 1,3-butadiene (manufactured by Nippon Elastomer Co., Ltd., Solblen T-414) was used. ) A concentrated latex was produced in the same manner as in Example 1 (solid content concentration 55% by weight).

The block copolymer latex and vinyl acetate-ethylene copolymer emulsion (manufactured by Dainippon Ink & Chemicals Co., Ltd., Everdik BP-11, solid content 54%) were mixed in a ratio of 50:50 and 75:25 in terms of solid content. Mix in proportion. A uniform dispersion was obtained by simple stirring.

Perform the same operation as in Example 1. The results are shown in Table 3.

As is clear from the above examples and comparative examples, the aqueous latex and rubber latex of a block copolymer consisting of a conjugated diolefin and a monovinyl-substituted aromatic compound,
A film obtained from a block copolymer latex composition consisting of a synthetic resin emulsion, a polymer, or a mixture thereof at a drying temperature of 70°C or lower is dried at a temperature of 80°C or higher. The product of the square of temperature (unit: °C) and time (unit: minutes) is 10,
By heat treatment at a temperature and time of 0.000 to 500,000. The tensile properties of the composition films were significantly improved.

Claims (1)

[Claims] 1 (A) A block copolymer consisting of a conjugated diolefin block and a monovinyl-substituted aromatic compound block obtained by a solution polymerization method, with a molecular weight of 5,000 to 500,000 and a monovinyl-substituted aromatic compound content of 10 to 70% by weight. an aqueous latex containing at least one species;
B) Rubber latex. It consists of a synthetic resin emulsion or a mixture thereof, and has a solid content of 10 to 8.
5% by weight. (In a film obtained from a composition containing B1 in a proportion of 90 to 15% by weight, the film is heated at 70°C of the composition.
The film produced by drying at the following temperatures is dried at a temperature of 80°C or higher such that the product of the square of the temperature (in 2°C) and the time (in 2 minutes) is 10,000 to 500,000. A film of a block copolymer latex composition, characterized in that it is obtained by heat treatment at different temperatures and times.