JPH041790B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a new and useful backing agent, and more particularly, it has excellent dispersibility for fillers to be added, and is suitable for so-called hydrophobic fibers such as polypropylene, nylon, and polyester. The present invention relates to a backing agent that also has excellent adhesive properties. [Prior Art] Conventionally, pile fabrics and other various fabrics used for tufted carpets, upholstery fabrics, car seats, artificial lawns, etc., have problems such as fixation of the pile itself and failure of the secondary base fabric. pasting,
In addition, for the purpose of imparting dimensional stability and elasticity, a so-called polymer dispersion such as SBR latex, natural rubber latex or synthetic resin emulsion is usually added with various substances such as calcium carbonate or aluminum hydroxide, if necessary. Adhesive compounds containing various so-called additives such as inorganic fillers or thickeners are used, and a so-called bucking process is performed using them, but recently, the above-mentioned Split polypropylene yarn fabrics are increasingly being used as the primary base fabric (i.e., the fabric into which the pile is woven) for tufted carpets and artificial lawns. However, such propylene fabrics are non-polar and have almost no water absorption, so when backing treatment is performed using a composition containing a conventionally used polymer aqueous dispersion as an essential component, The adhesive strength of the secondary base fabric (that is, the backing base fabric), that is, the strength to resist peeling, is not sufficient, and the strength to resist removal of the pile threads also tends to be insufficient. On the other hand, in the manufacture of such carpets, there is a strong tendency to incorporate large amounts of inexpensive inorganic fillers as components of backing treatment compositions, that is, backing agents, in order to reduce production costs. There is a strong desire for a bucking material that has excellent dispersibility and that does not reduce adhesive strength even when a large amount of filler is added. [Problems to be Solved by the Invention] To this end, the present invention has been prepared in an attempt to solve various problems faced by the prior art as described below. (1) Conventional backing agents do not have sufficient adhesion to polypropylene base fabrics, and as a result, the pile fixing strength (thread removal strength) used for carpets and the peeling strength of secondary base fabrics are poor;
and (2) conventional backing agents lack the ability to stably blend and disperse large amounts of inorganic fillers, and in addition, the adhesion strength is significantly reduced due to the blending of such fillers. . [Means for Solving the Problems] In other words, the present inventors solved the above-mentioned problems and developed a backing material that has excellent filler dispersibility and also has excellent adhesive strength to polypropylene fabrics. As a result of intensive research to develop a new agent, we found that an anionic surfactant, an inorganic filler, and a specific polyalkylene glycol ether coexist.
Moreover, the polymer aqueous dispersion obtained by emulsion polymerizing a monomer mixture containing butadiene and ethylenically unsaturated carboxylic acid as essential monomer components in water,
We have completed the present invention by discovering that it can be a backing agent that best meets these requirements. That is, the present invention is a backing agent containing a specific aqueous polymer dispersion as an essential component, and this backing agent contains 1 to 5 parts by weight of an anionic surfactant, ethylene oxide, and propylene oxide in water. Coexisting with 0.1 to 5 parts by weight of polyalkylene glycol ether (b) obtained by randomly copolymerizing them at a molar ratio of 95:20 to 5:80 and 0.1 to 0.7 parts by weight of inorganic electrolyte (c). 10 to 89 parts by weight of butadiene, 0.5 to 10 parts by weight of at least one ethylenically unsaturated carboxylic acid,
and at least one other ethylenically unsaturated monomer copolymerizable with the butadiene and the ethylenically unsaturated carboxylic acid, by emulsion polymerizing a monomer mixture consisting of 1 to 89.5 parts by weight. The dispersibility of the filler is such that in the emulsion polymerization, the amount of water is from 80 to 100 parts by weight per 100 parts by weight of the monomer mixture. To provide a backing agent comprising an extremely useful polymer aqueous dispersion as an essential component, which exhibits excellent adhesion to substrates made of hydrophobic fibers such as polypropylene. It is. Here, first, the monomer butadiene described above internally plasticizes the polymer dispersion, and at the same time,
This raw material component is used to impart elasticity to the polymer dispersion and give a desirable texture to the carpet after backing.
If the proportion of the monomer is less than 10 parts by weight, the elasticity of the film will be insufficient and the texture of the carpet after backing will become stiff, making it unsuitable for practical use. do not have. On the other hand, if it exceeds 89 parts by weight, the strength of the film will decrease, which is not preferable because the pull-out strength of piles in carpets and the like and the peel strength of secondary base fabrics will also decrease. Next, in the present invention, the total amount of the monomer mixture is 100
0.5 to 10 parts by weight of at least one ethylenically unsaturated carboxylic acid must be included in each part by weight. Typical examples of such carboxylic acids include acrylic acid, methacrylic acid, itaconic acid, and fumaric acid. It is a raw material component necessary to improve the properties and adhesion of the film to the substrate, and if the content is less than 0.5 parts by weight in 100 parts by weight of the total monomer mixture, such effects can be obtained. It becomes difficult to get caught,
On the other hand, if it exceeds 10 parts by weight, the water resistance of the film will decrease, which is not preferable. In addition, typical copolymerizable ethylenically unsaturated monomers mentioned above include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, and (meth)acrylate. butyl acid, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate,
(meth)acrylic acid alkyl esters such as octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate or octadecyl (meth)acrylate; styrene, α-methylstyrene,
Aromatic vinyl monomers such as chlorostyrene, 2,4-dibromustyrene or vinyltoluene;
Unsaturated nitriles such as (meth)acrylonitrile; vinyl esters such as vinyl acetate or vinyl propionate; vinylidene halides such as vinylidene chloride or vinylidene bromide;
Hydroxyalkyl esters of (meth)acrylic acid such as 2-hydroxyethyl (meth)acrylate or 2-hydroxypropyl (meth)acrylate; glycidyl esters of (meth)acrylic acid such as glycidyl (meth)acrylate or (meth)acrylamide, N-methylol (meth)acrylamide, N-butoxymethylacrylamide, or diacetone acrylamide, and these monomers are used together with the butadiene to form a polymer main chain, or For example, it is a raw material component used for the purpose of introducing functional groups to form intermolecular crosslinks, but it also provides the texture and water resistance of carpets, etc.
In order to obtain the desired effect, at least one of the monomers may be appropriately selected and used within the range of 1 to 89.5 parts by weight in 100 parts by weight of the monomer mixture. On the other hand, what is particularly important in preparing the bucking agent of the present invention is first to make the anionic surfactant (a) coexist in the aqueous medium.
Emulsion polymerization using a combined emulsion system of such an anionic surfactant and a nonionic surfactant is conventionally known. For example, U.S. Pat. No. 3,423,351 discloses a method for producing a monodisperse latex in the presence of an emulsifier that forms a combination system of anions and nonions, and West German Patent Application No. No. 1595308 discloses a method for producing a carboxylated styrene-butadiene copolymer dispersion containing 5 to 25 parts by weight of α,β-ethylenically unsaturated acid alkyl ester as a comonomer. In particular, in the invention described in the latter specification, the copolymer dispersion contains 0.5 to 5 parts by weight of a surface-active alkylaryl sulfonate and 9 to 50 moles of a surface-active alkylaryl sulfonate. Those prepared in the presence of a mixture consisting of ethylene oxide and 2 to 7 parts by weight of a reaction product of an alkylphenol are mentioned. However, the styrene-butadiene copolymer dispersion obtained using such an emulsifier mixture has unstable particles or is so viscous that it does not flow at all. On the other hand, in the present invention, together with this anionic surfactant (a), in particular, ethylene oxide and propylene oxide are mixed in a ratio of 95:20 to 5:80.
A nonionic surfactant called polyalkylene glycol ether (b) obtained by random copolymerization with a molar ratio of
(c) is also used, but in the coexistence of the three components (a), (b), and (c), emulsification is performed especially when the amount of water used for emulsion polymerization is limited to a specific range. By performing polymerization, a backing agent with excellent filler dispersibility and adhesion to the substrate can be obtained, and nonionic surfactants other than the polyalkylene glycol ether (b) Even if the polyalkylene glycol ether ( Even if b) exists, the remarkable effects described above cannot be obtained. Here, the above-mentioned anionic surfactant
Representative examples of (a) include fatty acid salts such as sodium oleate, alkyl sulfate salts, alkylbenzene sulfonates, alkyl sulfosuccinates, naphthalene sulfonates, polyoxyethylene alkyl sulfate salts, and alkanesulfonate salts. Examples include phonate sodium salt or alkyl diphenyl ether sulfonate sodium salt, and these emulsifiers are suitably used in a proportion of 1 to 5 parts by weight based on 100 parts by weight of the total monomer mixture. . If it is less than 1 part by weight, the polymerization rate becomes very slow and coagulates are formed in the dispersion after polymerization, which is not preferable.
On the other hand, if it exceeds 5 parts by weight, the particle size of the aqueous polymer dispersion becomes very small, making it difficult to obtain an aqueous dispersion with a low viscosity and resulting in poor dispersibility, which is preferable. do not have. Next, the above-mentioned polyalkylene glycol ether (b) is a mixture of ethylene oxide and propylene oxide in a ratio of 95:20 to an alcohol having an alkyl group such as methyl, ethyl, propyl or butyl group.
It refers to a compound having polymers (polymer chains) randomly copolymerized at a molar ratio of ~5:80, and among these, monoalkyl ether is particularly preferred. As a polyalkylene glycol ether, if the molar ratio of ethylene oxide is greater than 95, it will be difficult to obtain low viscosity water dispersibility and the dispersion will be poor; conversely, if it is less than 20, the polymerization rate will be low. As a result, a large amount of coagulum is likely to be formed in the aqueous dispersion after polymerization, which is not preferable. The emulsifier is suitably used in an amount of 0.1 to 5 parts by weight, preferably 0.1 to 1 part by weight, based on 100 parts by weight of the total monomer mixture, and if it is less than 0.1 part by weight, the viscosity is low. It becomes difficult to obtain an aqueous dispersion of the filler, and the dispersion of the filler also becomes scarce.On the other hand, if more than 5 parts by weight is used, the polymerization rate becomes extremely slow, resulting in Both are undesirable because a large amount of coagulum will be formed. Furthermore, typical examples of the above-mentioned inorganic electrolyte (c) include monovalent alkali metal salts, divalent or higher valent metal salts, or ammonium salts,
It is preferred to use monovalent metal salts or ammonium salts that do not make the polymerization system unstable. Specific examples of such inorganic electrolytes (c) include sodium pyrophosphate, potassium pyrophosphate, sodium tripolyphosphate, sodium hexamethanate, sodium chloride, potassium chloride, sodium sulfate, potassium sulfate, ammonium sulfate, sodium carbonate, and sodium hydrogen carbonate. Can be mentioned. The appropriate amount of the electrolyte (c) to be used is within the range of 0.1 to 0.7 parts by weight based on 100 parts by weight of the total monomer mixture, and if it is less than 0.1 parts by weight, a low viscosity aqueous dispersion should be used. is difficult to obtain, and furthermore, the dispersibility of the filler becomes poor. Conversely, if it exceeds 0.7 parts by weight, the weight rate becomes low and a large amount of coagulum is likely to be formed in the resulting aqueous dispersion. Therefore, neither is preferable. Furthermore, the amount of water used in emulsion polymerization is suitably within the range of 80 to 100 parts by weight per 100 parts by weight of the total monomer mixture, and if it is less than 80 parts by weight, it will be dispersed during the polymerization. This is not preferable because the body particles become unstable and may even gel.On the other hand, if the amount exceeds 100 parts by weight,
There is no point in using polyalkylene glycol ether (b) having a specific molar ratio as mentioned above, and in the end, the polyalkylene glycol is used as a nonionic surfactant to be used in combination in order to stably proceed emulsion polymerization A different species from ether (b),
Ethylene oxide and propylene oxide
Since it is limited to polyalkylene glycols having polymer chains randomly copolymerized with a molar ratio of 95:5 to 70:30, it is necessary to take advantage of the usefulness of the polyalkylene glycol ether (b) in the dilution angle. This is not desirable because it becomes In preparing the backing agent of the present invention, it may be carried out according to the usual emulsion polymerization method using the various raw materials listed above. For example, 10 to 89 parts by weight of the above-mentioned butadiene, at least one 0.5 to 10 parts by weight of ethylenically unsaturated carboxylic acid,
and at least one other copolymerizable ethylenically unsaturated monomer, 100 parts by weight of a monomer mixture consisting of 1 to 89.5 parts by weight of at least one other copolymerizable ethylenically unsaturated monomer are added to 80 to 100 parts by weight of water of each of the above-mentioned anionic monomers. Surfactant (a) 1
~5 parts by weight, and 0.1 to 5 parts by weight of a polyalkylene glycol ether (b) having a polymer chain randomly copolymerized with ethylene oxide and propylene oxide in a molar ratio of 95:20 to 5:80,
Emulsified and dispersed in a system containing 0.1 to 0.7 parts by weight of an inorganic electrolyte (c), an aqueous catalyst such as potassium persulfate, ammonium persulfate or hydrogen peroxide,
or by using a known and commonly used free radical generating catalyst such as an oil catalyst such as tert-butyl hydroperoxide or cumene hydroperoxide, preferably at a temperature range of 50 to 70°C.
Emulsion polymerization may be carried out over a period of time. In addition, when carrying out such emulsion polymerization, chain transfer agents such as tert-dodecyl mercaptan, antioxidants such as phenols, ultraviolet absorbers such as hydrazine derivatives, or emulsifiers such as ethylenediaminetetraacetate, etc. There is no problem in using various additives commonly used in polymerization. The aqueous polymer dispersion obtained in the above manner has a pH of
3 to 6, and a viscosity of 50 to 1000 cps. However, in order to further improve stability, it is preferably adjusted to a pH of 8 to 9 with an alkali. In addition, it is preferable to adjust the solid content of the aqueous polymer dispersion after emulsion polymerization to 50 to 60% by weight by a commonly used method such as stripping. The backing agent of the invention has excellent filler dispersibility and also has excellent adhesion to hydrophobic fibers such as polypropylene. It is suitable for use as a base resin for backing onto a substrate. [Effects of the Invention] Thus, surprisingly, the bucking agent of the present invention causes less occurrence of skinning phenomenon on the liquid surface due to drying during storage, and even more surprisingly, the When a carpet is manufactured using a backing adhesive compound obtained by incorporating a molecular water dispersion as an essential component, boiling occurs inside the adhesive when it dries, causing the adhesive to partially dissolve. This is useful because it can also prevent the phenomenon of "blistering", which occurs when carpets blow out onto the back side of the carpet and seriously impairs the appearance. In addition, due to its excellent adhesion to hydrophobic fibers, when the backing agent of the present invention is used as a binder for nonwoven fabrics and spunbond fabrics made of fibers with low water absorption such as nylon and polyester, it can be used as a binder for nonwoven fabrics and spunbonds made of fibers with low water absorption such as nylon and polyester. This provides extremely good adhesive strength compared to the case of using a conventional polymer aqueous dispersion obtained by emulsion polymerization using an agent. [Example] Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples. In the following, all parts and percentages are based on weight unless otherwise specified. Example 1 50 parts of butadiene, 47 parts of styrene, 3 parts of acrylic acid, and "Neoperex F-25"
A polymer in which 2.5 parts of [sodium alkylbenzene sulfonate manufactured by Kao Soap Co., Ltd.] as an active ingredient is randomly copolymerized with ethylene oxide (EO) and propylene oxide (PO) in a molar ratio of 50:50. 0.5 part of polyalkylene glycol ether with chain, 0.5 part of sodium pyrophosphate, 0.1 part of ammonium ethylenediaminetetraacetate, 0.3 part of tert-dodecyl mercaptan.
1 part, 0.3 parts of potassium persulfate, and 90 parts of ion-exchanged water were placed in a nitrogen-purged autoclave equipped with a stirrer, and emulsification mixing was performed at 60°C for 12 hours. Next, the pH was adjusted to about 8.5 with potassium hydroxide, and unreacted monomers were removed and concentrated by stripping, so that the solid content was 55.3% and the pH was adjusted to about 8.5.
was 8.5, and a stable polymer aqueous dispersion with a Bruckheald viscosity (hereinafter the same) at 25°C of 260 cps was obtained. Hereinafter, this will be abbreviated as bucking agent (A). Afterwards, using this bucking agent (A),
An adhesive compound for carpet backing was prepared in the proportions shown in the table, and then applied to 1 m ² of tufted carpet consisting of acrylic loop pile and polypropylene primary base fabric.
After applying the above compound to a weight of 1400 g (wet weight), jute was laminated as a secondary base fabric and dried in a hot air dryer at 140° C. for 10 minutes to prepare a carpet. Next, this carpet was cut to a width of 5 cm, and the peel strength of the secondary base fabric and the thread removal strength of the acrylic loop pile were measured using a Tensilon at a tensile speed of 100 mm/min. The results are summarized in Table 2. Example 2 The same procedure as in Example 1 was carried out, except that the same amount of polyalkylene glycol ether with an EO:PO molar ratio of 90:10 was used, and the solid content was 55.0%.
A stable polymer aqueous dispersion with a pH of 8.6 and a viscosity of 120 cps was obtained. Hereinafter, it will be abbreviated as backing agent (B). Thereafter, a carpet was produced in the same manner as in Example 1, except that the backing agent (B) obtained in this way was used, and the peel strength and suture removal strength were measured in the same manner. Shown in the table. Comparative Example 1 Same as Example 1 except that the monomer composition was changed to 50 parts of butadiene and 50 parts of styrene, but the solid content was 55.0%, the pH was 8.7, and the viscosity was
A control polymer aqueous dispersion of 990 cps was obtained. Hereinafter, this will be abbreviated as a backing agent (C'). Thereafter, a control carpet was prepared in the same manner as in Example 1, except that this backing agent (C') was used, and the various strengths were measured in the same manner. The results are summarized in Table 2. Comparative Examples 2 to 4 First, the amount of ion exchange water used for emulsion polymerization was
Emulsion polymerization was carried out in the same manner as in Example 1 except that the amount was changed to 120 parts, but agglomeration of particles occurred during polymerization and an aqueous polymer dispersion could not be obtained (Comparative Example 2). Next, the same amount of polyalkylene glycol ether with a molar ratio of EO and PO of 10:90 was used, and the amount of ion exchange water used for emulsion polymerization was 90 parts (in the case of Comparative Example 3) and 120 parts ( Emulsion polymerization was carried out in the same manner as in Example 1, except for the change in Comparative Example 4). In both cases, agglomeration of particles occurred during polymerization, making it impossible to obtain an aqueous polymer dispersion. I couldn't do it. As is clear from these results, even when the amount of water used for emulsion polymerization deviates from the range specified in the present invention, the molar ratio of EO:PO in the polyalkylene glycol ether can be changed according to the present invention. It is known that even when the amount is outside the range, emulsion polymerization cannot proceed stably, and therefore the desired backing agent cannot be obtained. Comparative Examples 5 and 6 First, emulsion polymerization was carried out in the same manner as in Example 1, except that no polyalkylene glycol ether was used, and control samples were prepared with a solid content of 55.0%, a pH of 8.6, and a viscosity of 1200 cps. An aqueous polymer dispersion was obtained (Comparative Example 5). Hereinafter, this will be abbreviated as a bucking agent (D'). On the other hand, emulsion polymerization was carried out in the same manner as in Example 1, except that no potassium pyrophosphate was used, and the resulting control polymer aqueous dispersion had a solid content.
55.0%, PH was 8.7, and viscosity was 2000 cps (Comparative Example 6). Below, this is called a backing agent (E′).
It is abbreviated as As is clear from these results, without any use of polyalkylene glycol ether (b),
Alternatively, if the use of the inorganic electrolyte (c) is completely omitted, the viscosity of the resulting polymer water decomposition solution becomes extremely high, exceeding the viscosity range in which a normal backing adhesive compound can be prepared. Thereafter, Example 1 was repeated, except that the backing agent (D') or (E') was used.
A control adhesive compound was prepared in the same manner as above, and as mentioned above, the viscosity of (D') and (E') was both high, and the product of the present invention was also mechanically stable to the touch. In other words, an inferior product was obtained compared to (A) and (B) above, and a control carpet was then prepared in the same manner as in the example except that both of these control adhesive compounds were used. When the performance of each carpet was evaluated in the same manner, it was found that both the peel strength of the secondary base fabric and the removal strength of the pile were inferior, and blister phenomenon was also observed. These results are summarized in Table 2.

[Table] Used.
** Antifoaming agent manufactured by San Nopco Co., Ltd.

[Table] As is clear from the results in Table 2, the backing agent of the present invention is known to have high adhesive strength, and therefore is not only an excellent backing agent but also an excellent backing agent. It is known that it is also useful as a base resin.

Claims (1)

[Claims] 1 Polymer obtained by randomly copolymerizing (a) 1 to 5 parts by weight of an anionic surfactant and (b) ethylene oxide and propylene oxide in water at a molar ratio of 95:20 to 5:80. 0.1 to 5 parts by weight of alkylene glycol ether and (c) inorganic electrolyte.
10 to 89 parts by weight of butadiene, 0.5 to 10 parts by weight of at least one ethylenically unsaturated carboxylic acid, and at least one or more of the above butadiene and ethylene. A method of carrying out emulsion polymerization of a monomer mixture consisting of 1 to 89.5 parts by weight of other ethylenically unsaturated monomers copolymerizable with the ethylenically unsaturated carboxylic acid, and the amount of water is the monomer mixture as described above. A backing agent obtained by carrying out emulsion polymerization in a range of 80 to 100 parts by weight per 100 parts by weight of the total amount of the bulk mixture.