JPH0881869A - Copolymer latex for rock fiber aggregate, adhesive composition for rock fiber aggregate, and rock fiber aggregate - Google Patents

Abstract

(57) [Summary] [Purpose] Sufficient strength and low compressive residual strain can be imparted to rock fiber aggregates, and excellent operability can be brought about in the manufacturing process of rock fiber aggregates. An adhesive composition containing a polymer latex is provided. [Structure] For a lock fiber assembly obtained by emulsion polymerization of a monomer comprising 10 to 30% by weight of an ethylenically unsaturated acid monomer and 70 to 90% by weight of another monomer copolymerizable therewith. An adhesive composition for a lock fiber assembly, which comprises a copolymer latex. [Effect] It contains a copolymer latex capable of imparting sufficient strength and a small compressive residual strain to the rock fiber aggregate, and capable of providing excellent operability in the production process of the rock fiber aggregate. An adhesive composition can be provided.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a copolymer latex for a lock fiber assembly, an adhesive composition for a lock fiber assembly, and a lock fiber assembly.

[0002]

2. Description of the Related Art Lock products are used for vehicle seats, chairs, sofas, beds, and water-permeable materials for civil engineering. Such a lock product is composed of a lock fiber aggregate in which various lock fibers such as palm, cotton, jute, polyester, nylon, polypropylene, aromatic polyamide, acrylic fiber or glass fiber are bulky bonded.
When bonding the lock fibers, an adhesive composition containing a copolymer latex is usually used. The copolymer latex used for the adhesive is required to have sufficient strength for the lock fiber aggregate and to have a property of reducing the compression residual strain of the lock fiber polymer. To meet such demands, an adhesive composition containing a copolymer latex obtained by using a specific oligomer as a polymerization emulsifier has been provided (Japanese Patent Publication No. 6-51869). The improvement of sex is insufficient and further improvement is required.

Further, the lock fiber aggregate is applied by spraying an adhesive composition containing a copolymer latex onto the lock fiber or by squeezing it with a roll after immersion, and then drying the lock fiber. Are joined and manufactured. Therefore, it is required that the adhesive containing the copolymer latex does not cause clogging of the spray nozzle and does not cause gum-up trouble on various rolls, that is, it has excellent operability. No one has been proposed that can satisfy even such demands.

[0004]

DISCLOSURE OF THE INVENTION As a result of intensive studies made by the present inventor in view of the above circumstances, 10 to 30% by weight of an ethylenically unsaturated acid monomer and another monomer 70 copolymerizable therewith are used. An adhesive composition containing a copolymer latex obtained by emulsion-polymerizing 90% by weight of a monomer provides a rock fiber assembly with sufficient strength, reduces compression residual strain, and is produced. It has been found that the process has excellent operability, and the present invention has been completed based on such findings.

[0005]

Thus, according to the present invention, a monomer consisting of 10 to 30% by weight of an ethylenically unsaturated acid monomer and 70 to 90% by weight of another monomer copolymerizable therewith. There is provided a copolymer latex for a lock fiber assembly obtained by emulsion polymerization of a body. Further, according to the present invention,
There is provided an adhesive composition for a lock fiber assembly, which comprises the copolymer latex for a lock fiber assembly. Further, according to the present invention, there is provided a rock fiber aggregate characterized by being bonded with the above-mentioned adhesive composition for a lock fiber aggregate.

The copolymer latex of the present invention is obtained by emulsion polymerization of a monomer comprising 10 to 30% by weight of an ethylenically unsaturated acid monomer and 70 to 90% by weight of another monomer copolymerizable therewith. Obtained. Examples of ethylenically unsaturated acid monomers include unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid and cinnamic acid; unsaturated dicarboxylic acids such as itaconic acid, fumaric acid and maleic acid; butenetricarboxylic acid and the like. Unsaturated tricarboxylic acids; monoalkyl esters of unsaturated dicarboxylic acids such as itaconic acid monoethyl ester, fumaric acid monobutyl ester, maleic acid monobutyl ester; acrylic acid sulfoethyl Na salt, methacrylic acid sulfopropyl Na salt, acrylamidopropane sulfone Examples thereof include unsaturated sulfonic acids such as acids or alkali salts thereof. Among these, preferable ones are unsaturated carboxylic acids, and particularly preferable ones are unsaturated monocarboxylic acids. These ethylenically unsaturated acid monomers may be used alone or in combination of two or more.

In the present invention, the ethylenically unsaturated acid monomer is 10 to 30% by weight, preferably 15 to 2 out of 100% by weight of the monomer component constituting the copolymer latex.
It is characterized by containing 5% by weight. In the conventionally used latex, the amount of the ethylenically unsaturated acid monomer is about 2.5% by weight, and a latex containing a small amount of such an acid monomer cannot achieve the object of the present invention. That is, the content of the ethylenically unsaturated acid monomer is 10
If it is less than wt%, the resulting rock fiber aggregate cannot be provided with sufficient strength and low compression set. On the other hand, when it exceeds 30% by weight, the viscosity of the copolymer latex becomes high, which is not practical and may cause gelation during the polymerization to make it impossible to obtain the latex.

Monomers copolymerizable with the ethylenically unsaturated acid used in the present invention include 1,3-butadiene, 2-methyl-1,3-butadiene and 2,3-dimethyl-1,3-. Aliphatic conjugated diolefins such as butadiene and halogen-substituted products thereof; aromatic vinyl compounds such as styrene, α-methylstyrene, monochlorostyrene, vinyltoluene; methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, Alkyl esters of acrylic acid and methacrylic acid such as butyl acrylate and acrylic acid-2ethylhexyl; ethylenically unsaturated nitrile compounds such as acrylonitrile and methacrylonitrile; and further β-hydroxyethyl acrylate, acrylate, methacrylamide, N
-Methylol acrylate, glycidyl acrylate, glycidyl methacrylate, divinylbenzene, diallyl phthalate, ethylene glycol diacrylate,
Examples thereof include ethylene glycol dimethacrylate, trimethylolpropane triacrylate, dimethylamino methacrylate, diethylaminomethyl acrylate, vinyl pyridine, vinyl acetate, vinyl chloride and the like.

These copolymerizable monomers may be used alone or in combination of two or more. The combination method when two or more kinds are used is arbitrary. Preferred combinations include, for example, aliphatic conjugated diolefins and aromatic vinyl compounds; aliphatic conjugated diolefins, aromatic vinyl compounds and ethylenically unsaturated nitrile compounds; aliphatic conjugated diolefins and alkyl (meth) acrylic acid. A combination including an ester and the like and an aliphatic conjugated diolefin is preferable. The method of combining the monomers is appropriately selected according to the performance required for the final lock product, and as an example, when oil resistance is required, an aliphatic conjugated diolefin and an ethylenically unsaturated nitrile compound are used. When light resistance or heat resistance is required, it is an alkyl ester of an aliphatic conjugated diolefin and (meth) acrylic acid.

The amount of the monomer copolymerizable with the ethylenically unsaturated acid is 70 to 90% by weight, preferably 75 to 85% by weight in the monomer components constituting the copolymer latex. . In the present invention, it is preferable to use two or more kinds of monomers containing an aliphatic conjugated diolefin as a monomer monomer copolymerizable with an ethylenically unsaturated acid. In this case, a copolymer latex is used. Constituent monomer component 10
The composition of 0 wt% is 10 to 3 ethylenically unsaturated acid monomers.
0% by weight, 30-60% by weight of conjugated diolefins and 10-60% by weight of other copolymerizable monomers. By setting the amount of the conjugated diolefin in the above range, the strength and compressive residual strain of the obtained rock fiber aggregate can be made more preferable.

The copolymer latex of the present invention is characterized in that it has the above-mentioned monomer composition, that is, it contains a large amount of ethylenically unsaturated acid monomer. Less than 90% by weight, preferably 30
Excellent strength characteristics are obtained when the content is from 85% by weight to 85% by weight. The gel amount of the copolymer latex in the present invention is generally controlled by the use of a molecular weight modifier used in ordinary emulsion polymerization or a combination of the use of a molecular weight modifier and the copolymerization of a crosslinkable monomer. can do.
Further, the amount of gel can be controlled by setting the polymerization temperature or regulating the polymerization conversion rate at the end of the polymerization reaction. Examples of the molecular weight modifier include mercaptans such as octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan and t-hexadecyl mercaptan; carbon tetrachloride,
Halogenated hydrocarbons such as carbon tetrabromide and methylene chloride;
Examples thereof include xanthogens such as dimethylxanthogen disulfide; hydrocarbons such as α-methylstyrene dimer. Examples of the crosslinkable monomer include divinylbenzene, diallyl phthalate, ethylene glycol diacrylate and trimethylolpropane triacrylate.

The method for producing the copolymer latex in the present invention is not particularly limited, and known emulsion polymerization can be used. For example, batch emulsion polymerization, semi-continuous emulsion polymerization, or continuous emulsion polymerization may be used. Alternatively, seed polymerization using seed latex, multi-stage polymerization, or power feed polymerization in which the composition ratio of added monomer components is continuously or intermittently changed can be used. In these emulsion polymerization, various known emulsifiers, polymerization initiators, chelating agents,
An electrolyte, a dispersant, a pH adjuster, etc. can be used. The polymerization temperature may be either high or low. Further, a known pH adjuster, dispersant, emulsifier, antiseptic, antifungal agent, antifoaming agent and the like can be added to the latex after the polymerization. It may also include a step of removing residual monomer from the polymerized latex or concentrating it.

The solid content concentration of the obtained latex is 30-
75% is typical. If it is less than 30%, the transportation fee per solid content is too high to be practical. On the other hand, if it exceeds 75%, the viscosity of the latex becomes so high that it is difficult to handle, which is not practical.

The copolymer latex for a lock fiber assembly obtained by the present invention can be used as it is as a lock fiber assembly adhesive composition, but it may be diluted with water or blended with other additives. You may use it. As additives, known emulsifiers, dispersants, defoamers, antioxidants, ultraviolet absorbers, fillers, colorants, vulcanizing agents, vulcanization accelerators, crosslinking agents, auxiliary agents for crosslinking agents, preservatives, Thickeners, penetrants, flame retardants and the like are used. As a method of preparing the adhesive composition, a known method can be applied, and a method of adding a copolymer latex for a lock fiber assembly to a polymer tank, an additive, and if necessary, water and mixing with a stirrer is generally used. Target.

A known method such as a dipping impregnation method, a spray method or a foaming method can be used as a method for applying the obtained lock fiber aggregate adhesive composition to the lock fiber. When the lock fiber aggregate adhesive composition of the present invention is used, the spray nozzle is not clogged in the process of producing the lock fiber aggregate, and gum up does not occur in various rolls, so that excellent operability is obtained. . Examples of the operability include a copolymer latex and a mechanical stability test of an adhesive composition by a Marlon mechanical stability tester (test conditions and the like are as described in Examples). In this test, it is important that the amount of agglomerates is small, and preferably the ratio of agglomerates is based on 100 parts by weight of the solid content of the latex or adhesive composition used in the Marlon mechanical stability test. It is less than 1%, more preferably less than 0.1%.

The lock fiber aggregate adhesive composition of the present invention can be applied to various lock fibers, for example, palm, cotton, jute, polyester, nylon, polypropylene, aromatic polyamide, acrylic fiber or glass fiber. Is mentioned. These lock fibers may be used alone or in combination of plural kinds of fibers. The fiber may be a new fiber produced from a fiber raw material, or may already be cut or woven for recycling use such as a rock fiber aggregate, a non-woven fabric or a woven fabric. Further, it is also possible to treat these rock fibers with the above-mentioned additive chemical liquid before applying the lock fiber aggregate adhesive composition, or after applying the adhesive agent, further treat with the above-mentioned additive chemical liquid. Generally, a lock fiber aggregate is obtained by applying a lock fiber aggregate adhesive composition to lock fibers and then drying with a hot air or the like. The drying method is not particularly limited, and a known method can be used.

The thus-obtained rock fiber aggregate is used as a material for rock products such as vehicle seats, chairs, sofas, beds, and water-permeable materials for civil engineering, and has excellent tensile strength, compressive strength and compressive residual strain. It is possible to provide rock products with excellent quality.

The preferred embodiments of the present invention will be described below. (1) Rock fiber of the present invention obtained by emulsion polymerization of a monomer comprising 15 to 25% by weight of an ethylenically unsaturated acid monomer and 85 to 75% by weight of another monomer copolymerizable therewith Copolymer latex for aggregates. (2) Emulsion polymerization of a monomer comprising 10 to 30% by weight of an ethylenically unsaturated acid monomer, 30 to 60% by weight of a conjugated diolefin and 10 to 60% by weight of another copolymerizable monomer. The resulting copolymer latex for rock fiber aggregates of the present invention. (3) The copolymer latex for a lock fiber assembly according to the present invention, wherein the ethylenically unsaturated acid monomer is an unsaturated carboxylic acid. (4) The copolymer for a lock fiber assembly of the present invention, wherein the other monomer copolymerizable with the ethylenically unsaturated acid monomer is two or more kinds of monomers containing an aliphatic conjugated diolefin. latex. (5) The lock fiber assembly adhesive composition of the present invention obtained by diluting a copolymer latex for lock fiber assembly with water.

[0019]

EXAMPLES Examples will be shown below, but the present invention is not limited to the following examples. In the following examples, the proportions of compositions are parts by weight unless otherwise specified.

Example A polymerization vessel previously purged with nitrogen was charged with ion-exchanged water, an emulsifier, an inorganic salt and a chelating agent, and then the monomers and the molecular weight modifier shown in Table 1 were charged. Stirring was started, the contents were mixed, and the temperature was raised to 70 ° C. When the temperature in the polymerization vessel reached 70 ° C., a polymerization initiator dissolved in ion-exchanged water was separately injected into the polymerization vessel to start the polymerization reaction.
The temperature was maintained at 70 ° C., the reaction was carried out for 15 hours, and then water cooling was performed. The polymerization conversion rates were all over 98%. After removing the unreacted monomers of the obtained copolymer latex, the pH of the copolymer latex was adjusted to 7.0 with sodium hydroxide. The gel amount of these latexes was measured and is shown in Table 1.

The amount of gel was determined by the following method. A dry film is formed at room temperature so that the thickness of the sample latex when dried is 0.2 mm, and this dry film is subdivided into a size of about 5 mm square, and about 0.5 g thereof is precisely weighed and divided. I took it. On the other hand, a basket made of 100 mesh stainless steel wire mesh is precisely weighed. The separated film was placed in a stainless mesh basket and the whole basket was allowed to stand in a 100 ml glass beaker. 60 ml of benzene was poured into a glass beaker and left at room temperature for 24 hours. After that, take out the stainless steel basket containing the fragmented film from the beaker,
It was dried in a vacuum dryer for 12 hours. The weight of the insoluble matter in the film was determined by precisely weighing each of the dried stainless steel baskets. The ratio of the weight of the insoluble matter of the film to the original weight of the film was calculated in percentage, and the numerical value was taken as the gel content of the copolymer latex.

Each of the obtained copolymer latices was diluted with water to a solid content concentration of 10% to prepare each adhesive composition. The mechanical stability of these adhesive compositions was measured by a Marlon type mechanical stability tester and is shown in Table 1.
The method of the Marlon mechanical stability test was performed as follows. Latex adhesive composition 100 having a solid content of 10%
After filtering g with a 100-mesh wire net, a test with a load of 15 Kg for 10 minutes was performed using a Marlon mechanical stability tester. The latex adhesive composition after the test was filtered through a 100-mesh wire net, and the aggregates filtered on the wire net were collected.
The obtained aggregate was dried and weighed to determine the amount of aggregate generation (g). The mechanical stability was represented by the ratio (%) of the amount of aggregate generation to the solid content weight of the latex adhesive composition tested.

These adhesive compositions were made to have a length of 100 mm,
2 g of solid content was spray-coated on the surface of palm fiber having a width of 100 mm, a thickness of 30 mm and a weight of 5 g, and dried in a hot air dryer at 120 ° C. for 10 minutes. Further, the back surface was similarly spray-coated and dried to prepare a palm lock test piece. Tensile strength using these test pieces,
The compression set was measured. The results are shown in Table 1.
The tensile strength was measured using an Instron tensile tester. The compression residual strain was measured according to JIS K6382.

Comparative Example For comparison, a copolymer latex having a predetermined monomer composition shown in Table 1 was prepared in the same manner as in Example to obtain a copolymer latex.
The amount of gel was determined. Then, the adhesive composition was prepared in the same manner as in the example, and the mechanical stability was determined. Further, palm lock test pieces were prepared using them, and the tensile strength and the residual compression strain were measured. The results are shown in Table 1.

[0025]

[Table 1]

From Table 1, examples of the present invention (Experiment Nos. 1 to 7)
It is understood that the copolymer latex (1) has an agglomerate generation ratio of less than 0.1% and is excellent in operability. Further, it is understood that the adhesive composition containing the copolymer latex can impart sufficient strength and low compressive residual strain to the rock fiber aggregate. On the other hand, the copolymer latex obtained by using the monomer mixture containing no ethylenically unsaturated acid monomer (Comparative Example, Experiment Nos. 8, 11 and 12) had a high generation rate of aggregates. , It is found that the operability is poor. Further, it is found that when the adhesive composition containing the copolymer latex is used, sufficient strength cannot be given to the rock fiber aggregate, and the compression residual strain becomes large. Copolymer latex obtained by using a monomer mixture having a low content of ethylenically unsaturated acid monomers (comparative example,
When an adhesive composition containing Experiment No. 9) was used,
It can be seen that sufficient strength cannot be given to the rock fiber aggregate and the compressive residual strain also increases.
When a monomer mixture containing a large amount of ethylenically unsaturated acid monomer was used (Comparative Example, Experiment No. 10), gelation occurred during polymerization and a latex could not be obtained.

[0027]

As described above, by using the adhesive composition containing the copolymer latex of the present invention, it is possible to impart sufficient strength and a small compressive residual strain to the rock fiber aggregate, and also to provide the lock. Excellent operability can be brought about in the manufacturing process of the fiber assembly.

Claims (3)

[Claims] 1. An ethylenically unsaturated acid monomer 10 to 30% by weight and another monomer 70 to 90% by weight copolymerizable therewith.
A copolymer latex for a lock fiber assembly obtained by emulsion-polymerizing a monomer comprising 2. An adhesive composition for a lock fiber assembly, which comprises the copolymer latex for a lock fiber assembly according to claim 1. 3. A lock fiber assembly obtained by bonding with the adhesive composition for a lock fiber assembly according to claim 2.