JPS5845211A - Latex of conjugated diolefin copolymer - Google Patents

Abstract

PURPOSE:To provide the titled latex having excellect adhesivity, water resistance, strength, and solvent resistance, and derived from 1-acetoxy-1,3-butadiene, 1,3-butadiene, an aromatic vinyl compound, and an ethylenic unsaturated carboxylic acid, etc. CONSTITUTION:A monomer mixture composed of (A) 0.1-60(wt)% 1-acetoxy-1,3- butadiene, (B) 5-90% 1,3-butadiene and/or 2-methyl-1,3-butadiene, (C) 0.5-90% aromatic vinyl compound (e.g. styrene), (D) 0.1-20% ethylenic unsaturated carboxylic acid (e.g. acrylic acid) and (E) 0-70% other copolymerizable vinyl compound (e.g. methyl acrylate), is if necessary mixed with an emulsifying agent (anionic and/or nonionic surface active agent), a polymerization initiator (e.g. sodium persulfate, etc.), a chain transfer agent, etc. in an aqueous medium, and subjected to the emulsion polymerization at 5-100 deg.C to obtain the objective copolymer latex (including the latex having saponified acetoxy group).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel conjugated diolefin copolymer latex.
3-butadiene, aromatic vinyl compound, ethylenically unsaturated carboxylic acid.

Or it relates to a copolymer obtained by emulsion polymerization of a monomer mixture consisting of a vinyl compound copolymerizable with these and a saponified copolymer latex thereof.

Carboxy-modified styrene-butadiene copolymer latex is one of the polymer latexes widely used in the fields of fiber 1 paper and paints. The copolymer latex has better adhesion, water resistance, elasticity, and water resistance than other polymer latexes.
Paper is currently used because it is superior in terms of stability.

, widely used in textile and other fields.

The inventors of the present application further investigated the modification of this excellent copolymer latex, and found that 1-acetoxy-1,3-butadiene (hereinafter referred to as B
It was discovered that a copolymer latex with excellent adhesion, water resistance, solvent resistance, etc. can be obtained by introducing DA (abbreviated as DA), and in particular, the copolymer latex is used as a binder for coated paper. Then it becomes adhesive.

Printability, gloss, but also adhesion and texture when used as a binder for carpet backing.

The present invention was completed by discovering that this latex has extremely excellent aging resistance.

That is, the object of the present invention is BDD A O, 1 to 60% by weight.

5 to 90% by weight of 1,3-butadiene (hereinafter abbreviated as B and D) and/or 2-methyl-1,3-butadiene, and 0.5 to 90% by weight of an aromatic vinyl compound.

Achieved by a copolymer latex obtained by emulsion polymerization of a monomer consisting of 01 to 20% by weight of ethylenically unsaturated carboxylic acid and 0 to 70% by weight of a vinyl monomer copolymerizable with these, and a saponified latex thereof. be done.

BDA used in the present invention can be obtained by acetoxylating 13D in the presence of a noble metal catalyst such as palladium, or by heating crotonaldehyde in the presence of acetic anhydride and an acetate of an alkali metal. BDA obtained by these reactions is a mixture of cis form and trans form, but the monomer used in the present invention may be a single cis form or a trans form, or a mixture of these forms. good. Further, it may contain impurities to the extent that it does not cause any inconvenience.

If the amount of nDA used is less than 0.1% by weight, the effects of the present invention cannot be obtained, and if it exceeds 60% by weight, the inherent properties of the carboxy-modified styrene-butadiene copolymer latex will be impaired. Among aromatic vinyl compounds, styrene,
Includes α-methylstyrene, monochlorostyrene, vinyltoluene, methoxystyrene, etc.

Ethylenically unsaturated carbodiic acids include unsaturated dicarboxylic acids or monoesters of dicarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, fumaric acid, and maleic acid. Other copolymer vinyl compounds include methyl acrylate, ethyl acrylate, methyl methacrylate, hydroxyethyl acrylate,
Acrylic acid hydroxypropyl ester.

Ethylenically unsaturated, mono- or dicarboxylic acid esters such as methacrylic acid hydroxyedyl ester, maleic acid dimethyl ester, acrylonitrile9. Vinyl cyanide compounds such as methacrylonitrile, vinyl chloride, vinylidene chloride.

Vinyl methyl ethyl ketone, vinyl methyl ether, vinyl acetate, vinyl formate, allyl acetate, meta-allyl acetate, acrylamide.

methacrylamide, N-methylolacrylamide,
Vinylpyridine, glycidyl acrylate, glycidyl methacrylate, acrolein.

Includes allyl alcohol.

The copolymer latex of the present invention is produced by ordinary emulsion polymerization at a polymerization temperature of 5 to 100°C, similar to ordinary carboxy-modified styrene-butadiene copolymer latex,
Batch, semi-batch, and continuous polymerization are all possible.

The polymerization can be carried out by a known method in an aqueous medium using an emulsifier, a polymerization initiator, and a chain transfer agent.

Anionic and/or nonionic surfactants are used as emulsifiers. Examples of the anionic surfactant include higher alcohol sulfate esters, alkylbenzene sulfoates, aliphatic sulfonates, and the like. In addition, as nonionic surfactants, ordinary polyethylene glycol alkyl ester type, alkyl ether type,
Alkylphenyl ether type etc. are used.

Water-soluble initiators such as sodium persulfate, potassium persulfate, and ammonium persulfate are used as initiators.

Either an oil-soluble initiator such as benzoyl peroxide or a dox-based initiator can be used. As chain transfer agents, chelating agents, inorganic salts, etc., those known for emulsion polymerization are used.

As the copolymer latex of the present invention, a latex obtained by saponifying the acetoxy group belonging to BDA can also be used. Saponification of the copolymer latex is usually carried out at a pH of 9 or higher, preferably 10 or higher, a temperature of 40 to 100°C, preferably 50 to 90°C, and a reaction time of 5 to 50 hours.

The method is not limited to this method. The degree of saponification can be determined by quantifying acetic acid produced during saponification or by measuring the infrared absorption spectrum of the saponified copolymer.

The copolymer latex thus obtained contains various clays, 100 parts of mineral pigments such as aluminum hydroxide, titanium dioxide, satin white, calcium carbonate, etc., and 3 to 50 parts as a solid color content per part. Furthermore, by using it in combination with other ingredients such as starch, casein, and polyvinyl alcohol, physical properties such as adhesive strength, printing gloss, and printability can be improved by using styrene-butadiene copolymer latex and styrene-butadiene-methacrylic acid. Significant improvements not seen in methyl copolymer latex can be seen.

Furthermore, in general, when formulating a high solids content, the fluidity of the coating composition increases, so it is necessary to reduce the amount of natural binder. This can be significantly improved.

As described above, the copolymer latex of the present invention is not only extremely effective as a binder for paper coatings, but also has applications that take advantage of the latex's characteristics of adhesiveness, water resistance, strength, solvent resistance, and elasticity.For example, it can be used for carpet backing. Binders, adhesives, adhesives, architectural or vehicle paints, non-woven fabrics.

Tire cord bonding, fiber treatment agents for flock products, foam rubber, sealants, cement, etc.
Suitable for a wide range of applications such as asphalt additive, heater additive 9, impregnation of paper, fibers, etc., latex for resins, etc.

EXAMPLES The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to these Examples.

In addition, the evaluation test of the coated paper in the examples was conducted according to the following method.

RI Pick: A test piece produced by an RI printing tester is fixed on a drum, and printing is continued repeatedly at a speed of 3 Orpm, and after a certain period of time, the test piece is stopped and judged. The scores are given as 5 points for those that were completely printed, and 1 point for those that were barely printed, and the five pieces of data obtained from each ceremony fee are averaged.

A sheet of paper fixed to a drum using a Wet Pick 2R printing tester was coated with water and printed once for a fixed period of time, and evaluated in the same manner as RI Bic.

Picking: Exactly the same as wet pick measurement, but printing was performed using ink with a lower tack value on a wider width than in wet pick measurement so as not to cause pick, and judged in the same way as RI Bic.

White paper gloss 5 Based on JIS method.

Print gloss: According to JIS method.

Stiffness: Gurley set stiffness example 1 A glass pressure-resistant bottle with a capacity of 500 QC under nitrogen gas, B
DA40,9. BD30,9. 28 g of styrene, 2 F fumaric acid, 0.3 g of sodium dodecylbenzenesulfonate, 200 g of water, 0.3 g of tert-dodecyl mercaptan, 0.3 f, sodium carbonate
,iy, charged with 0.5!9 otrium persulfate, 60℃
The reaction was carried out for 15 hours. Then N,N-diethylhydroxylamine 0. The reaction was stopped by adding IN. The polymerization rate was 98%. This copolymer was measured by GPC as a solution in tetrahydrofuran, and the molecular weight was determined by comparing it with polystyrene of known molecular weight, and the number average molecular weight was 5.
It was over 10,000. This aqueous dispersion was diluted with potassium hydroxide.
After adjusting plI to 5.0 using a % aqueous solution, the solid content was concentrated to 45% by vacuum distillation. This aqueous dispersion has few coagulums, good appearance, mechanical stability,
The chemical stability was also very good.

Example 2 Emulsion copolymerization of a monomer mixture having the following composition was carried out in the same manner as in Example 1 to obtain an aqueous dispersion of A-p (E and F are comparative examples).

The polymerization rate was 98 to 100%, and the number average molecular weight of each copolymer was 30,000 or more.

Mineral pigment (kaolin clay: UW-90; 14M
A paper coating composition with a color solid content of 60% was prepared by using an adhesive consisting of 100 parts (manufactured by &C), 10 parts solid content of the aqueous dispersion of A and -F, and 5 parts oxidized starch. . Table 2 shows the printing test results for coated paper.

(Note 2 E and F are comparative examples) In physical properties such as adhesive strength, white paper gloss, and printability, styrene-butadiene copolymer latex (sample E) and styrene-butadiene-methyl methacrylate copolymer latex (sample A significant improvement not seen in F) was observed.

Example 3 The aqueous dispersion B of Example 2, p■, was adjusted to pH=12 with an aqueous sodium hydroxide solution and left in a closed container at 70°C for 24 hours. The infrared absorption spectrum of the coagulated and dried aqueous dispersion revealed that the acetoxy groups were partially saponified.

In the same manner as in Example 2, a composition for coated paper was prepared using this partially saponified aqueous dispersion, and the composition was applied to 9 papers and a printing test was conducted. , a slight decrease in water resistance (wet bic) was observed, but FLI
It showed extremely excellent physical properties in terms of picking, inking, and gloss.

Table 3 It, I pick 4.4 Wet pick 4.2 Wet pick 4,2 White paper gloss (%)
65 Print gloss (%) 86 Example 4 The same aqueous dispersion as in Example 2 was used, and U was used as the mineral pigment.
W-90 and fine particle calcium carbonate, Carbital 90 (
A paper coating composition was prepared using a so-called high solids formulation with a color solids content of 68%, using 50:50 (manufactured by Fuji Kaolin Co., Ltd.) and 13 parts of latex alone as an adhesive, and coated on 9 papers. did. Table 4 shows the evaluation results of the physical properties and printability of these coated papers.

Table 4 (Note: E and F are comparative examples) Here again, the strength required for offset printing is 2nd layer.

In addition to being superior in terms of gloss, a significant improvement was also observed in terms of stiffness of coated paper, which is a problem in formulations that do not use natural binders.

Example 5 Emulsion polymerization was carried out in the same manner as in Example 1 using the monomer composition shown in Table 5 to obtain latexes of Q, H, and I (G is a comparative example). Then, 10 parts of potassium birophosphate and calcium carbonate were added in the amounts shown in Table 6, and the viscosity was measured with a thickener (a 4% aqueous solution of sodium polyacrylate (Aron 20p manufactured by Toagosei Corporation)) and water using a Brookfield M-type viscometer. ≠4 rotor +
26,000 eps measured at 5r,p,m
The solids content was adjusted to 75% to prepare an adhesive composition for soaking.

Table 5 Examples of latex polymerization Table 6 shows the results of evaluation as adhesives for car vent backing.

Table 6 Note: Those using Latex G are comparative examples, and the others are examples.

■ 88-30 manufactured by Nitto Funka ■ ■ The adhesive composition was applied to a raw fabric of nylon and loop pile at a solid content of 1. A test piece was prepared by applying Okg/trl and bonding jute together.

The texture of the test piece was examined by touch.

(2) The test piece obtained in (2) was cut into 5 pot width pieces and subjected to an autograph peel test. 3 points from the strongest 2 points from the weakest
The intensity of the points was averaged.

(2) The thread removal strength of the piles at five locations of the test piece obtained in (2) was measured using an autograph, and the average value is shown.

(2) The test piece obtained in (2) was subjected to an aging test for one week at 100° C. with the gear open, and changes in texture and discoloration at that time were examined.

○ No change in texture, no change in color △ No change in texture, change in color × Change in texture, change in color Previously, to obtain a "medium" texture, about 50 parts of latex ((1) from Butagene was used) By replacing part of styrene and butadiene with BDA, it was possible to improve the strength and aging resistance with the same texture (A,
(You can see this by comparing A). Furthermore, when the filling amount is increased, the texture becomes harder and the strength decreases. So latex σ
When D was used, the texture remained unchanged but the strength became stronger (I
). Also, if you want to soften the texture, it is better to increase the amount of butadiene, but in that case, if you use A or 13D (I)
Even when 500 parts by weight of filler was added, the same strength as (3) obtained by adding 400 parts by weight of filler to latex without BDA was obtained.

Patent applicant: Japan Synthetic Rubber Co., Ltd. Continued from page 1 ■Int, C1, 3 identification code Office reference number (C
08F 236104 220104 ) (C08F 212108 220104) 0 authors Masazo Nishida 1 Morikiyama-cho, Yokkaichi-shi 0 authors Yoshida Yoshinobu 2-29 Aobadai, Midori-ku, Yokohama 0 authors Hironobu Shinohara 810-1, Daguruma Takagasaka, Yokkaichi-shi

Claims (2)

[Claims] 1.1-acetoxy-1,3-butadiene 0.1-60
% by weight, 1,3-butadiene and/or 2-methyl-
1,3-butadiene 5-90% by weight, aromatic vinyl compound 0.5-90% by weight. A copolymer latex obtained by emulsion polymerization of a monomer mixture consisting of 0.1 to 20% by weight of an ethylenically unsaturated carboxylic acid and 0 to 70% by weight of another copolymerizable vinyl compound. 2.1-acetoxy-1,3-butadiene 0.1-60
% by weight, 1,3-butadiene and/or 2-methyl-
1,3-butadiene 5-90% by weight, aromatic vinyl compound 0.5-90% by weight, 6° ethylenically unsaturated carboxylic acid 0.1-20% by weight, other copolymerizable vinyl compounds 0
In a copolymer obtained by emulsion polymerization of a monomer mixture consisting of ~70% by weight, some of the acetoxy groups attributed to 1-acetoxy-1,3-butadiene contained in the copolymer Or fully saponified copolymer latex.