JPS5880305A - Resin having excellent waterproofness - Google Patents

Abstract

PURPOSE:The titled resin which is useful as adhesives, binders, etc., and capable of providing excellent waterproofness as soon as it is set, prepared by removing the solvent from a solution of a modified PVA having specified copolymer units under an acidic condition or a condition in which an acidic substance can be yielded during drying. CONSTITUTION:The titled resin is formed by removing the solvent from a solution of a modified PVA containing, in the molecule, copolymer units of the formula, wherein R' is H or a lower alkyl and R<2> is H or an alkyl (e.g., a saponificate of a copolymer of N-methoxymethylacrylamide or N-n-butoxymethylacrylamide and vinyl acetate) under an acidic condition or a condition in which an acidic substance is yielded during drying. The produced resin has various uses by utilizing waterproofness on crosslinking as well as the properties as PVA. This resin has a wide scope of applications such as textile size and surface size for paper.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the provision of a resin that can be molded into an adhesive, a binder, a coating agent, an emulsifier, a film, or a mold and at the same time provides excellent water resistance.

Polyvinyl alcohol (hereinafter abbreviated as PVA) has been known as an alternative water-soluble polymer, and is used as a 1-synthetic number - vinylon (i stands for 6) as a raw material for films, such as adhesives, binders, adsorbing agents, emulsifiers, etc. have been used in a wide range of industrial applications.

In these applications, it is often necessary to improve water resistance, and many methods for improving water resistance have been proposed. Regarding the technology related to water resistance and insolubilization to date, see "Popal" by Nagano 7, Yama Il, and Toyoshima (#C revised edition), Kobunshi Publishing Association (1981), 0256-261j.
[K has been reviewed. Formalin, acetaldehyde, etc. are used to make Vinylon O water resistant, but dialdehyde metals such as glyoxal and glutaraldehyde have not been put to practical use due to problems such as odor when making other glues and emulsifiers. Alternatively, polyaldehyde compounds such as dialldehyde starch are known as water-resistant agents for PVA, but in order to create a film that can withstand boiling water, it is necessary to increase the amount used, and heat treatment is also required. It has the disadvantage that it tends to get colored when it is used. N-methylol urea% N-methylol melane/also has the ability to provide water resistance, but has the disadvantage of emitting a formalin odor.

Compounds containing inorganic elements such as boron, titanium, zircon, chromium, and silicon also have crosslinking properties and are used for water resistance, but in many cases, when these are added to a PVA aqueous solution, it thickens or gels. If this occurs, the viscosity of the liquid becomes unstable, and sufficient care must be taken in practical use, and there are few examples of industrial use.

In contrast to the above-mentioned additives that provide water resistance, there are a few proposals to modify PVA itself to impart water resistance, but saponified products of O-arylidene diacetate and vinyl acetate O-copolymer are known. Modified PVA with aldehyde in the side chain
Easily crosslinked by acid treatment. However, increasing the amount of modification in order to provide sufficient water resistance tends to result in the formation of bridge insoluble materials during the production of PVA, and the tendency for coloring, so it has not yet been put into practical use. It is more difficult than expected to effectively and effectively impart water resistance or crosslinking properties, and a sufficiently effective method has not yet been known. In light of this situation, the inventors of the present study introduced a crosslinkable group that gives water resistance to PVA itself, and produced PVA at low cost, which has excellent solubility in solvents such as water before crosslinking. As a result of our research with the aim of establishing a method for

R1 each represents a hydrogen atom or an alkyl group.

) A solution of modified PVA containing copolymerized units represented by
The present invention has been completed by discovering that a resin with extremely high water resistance can be obtained by removing the solvent from an aqueous solution under acidic conditions or under conditions that produce acidic substances during drying.

The modified PVA used as a starting material in the present invention is itself a novel metal compound unknown heretofore. This degeneration P
VA is vinyl ester s and ewake vinegar Ill hi!
A,! : Formula CH*-CR' -CONHCHIO-
R” (R” ij hydrogen atom is lower alkyl group 1
m is a hydrogen atom (19 is an alkyl group) N-alco1P-methyl group-containing monomer; and) HHI is a hydrogen atom or a methyl group, and R3 is an alkyl group having 1 to 4 carbon atoms. -alkoxymethyl(meth)acrylic acid, particularly preferably N-methoxymethacrylic acid (meth)acrylic acid
1iN-n-buto-dimethylacrylide is copolymerized using a radical polymerization initiator, and then an alkali catalyst is applied to the alcohol** of this O copolymer to partially remove the vinyl ester units in the copolymer. It is produced by saponifying vinyl alcohol units either partially or to a high degree.

Vinyl esters that can be used in producing this modified PVA can be copolymerized and then saponified to become vinyl alcohol, so any vinyl ester can have essentially the same effect, but conventional vinyl esters Vinyl acetate is preferred from an economic standpoint.

In addition, in the alkoxymethyl group-containing monomer represented by CH*-CR"-CONHCH鵞0-R", R1 is a hydrogen atom or a lower alkyl group, but usually the hydrogen atom is preferably a methyl group, and 1 For 9R3, a hydrogen atom or an alkyl group having any chain length of 0 may be used in order to impart crosslinking properties, but an alkyl group having 1 to 4 carbon atoms is usually particularly preferred. A specific example of this monomer is N-
Methylol acrylide, N-methylolmethacryland, N-methoxymethylacryland, N-methoxymethylmethacrylide, N-ethoxymethylacrylide, N-ethoxymethylmethacrylamide, N
-n-propoxymethylacrylamide, N-propoquine methyl methacrylate (%) N-ingropoxymedelacrylamide (d), N-ingroxymethyl methacryl (d), dimethyl 7-thalylide in N-n-buto,
N-N-butoxymethylmethacrylate, N-inbutoxymethylmethacrylate, N-inoptoxymethylmethacrylate, N-t@rt-butdP dimethylacrylate, N-t. Among them, N-methoxymethylacrylamide and N-n-pFoxymethylacrylamide are preferred from the viewpoint of effectiveness and economy.

These monomers are well known in the art, and copolymers of vinyl acetate and acrylic esters are disclosed in, for example, British Patent No. 955,420. However, no good copolymer is known that can be produced by converting a copolymer of N-alkoxymethyl (meth)acrylide and vinyl ester.
It is completely unknown that a resin can be derived that has the excellent friend performance that is industrially superior to that shown in the present invention.

The above-mentioned copolymerization of 9N-alkoxymethyl (meth)acrylic ides and vinyl esters can be carried out by solid state polymerization, solution polymerization,
Although it can be carried out using any polymerization method such as turbidity polymerization or emulsion polymerization, #I liquid polymerization is usually preferred from the perspective of most of the present invention. Lower alcohols, especially methanol, are industrially suitable as solvents for use in solution polymerization.

Bulk polymerization and solution polymerization can be carried out in either one-minute or continuous mode. Suspension polymerization and emulsion polymerization are usually carried out in batch mode. It is well known that the monomer composition changes with the polymerization rate according to (rlr,), but one or both monomers are added to keep the monomer composition constant. It is desirable to employ a batch method to obtain a copolymer having a uniform copolymer composition. One way to calculate the amount of addition in this case is by Teki R, J, and Hanna.
industrial and1cmgin*sring
Ch@m1stry, Vol, 49.42, 208
-109 (ug57).

In the case of continuous multi-column copolymerization, for the same reason, it is desirable to add monomers to the second and subsequent columns so that the monomer composition in each column is constant. As a polymerization initiator, 2.2
'-azobisisobutyronitrile, 1,1'-azobis-(cyclohexane-1-carbonitrile), 2,2'
-Azobis-isobutyronitrile, 2,2'-azobis-(2,4-'/methylvaleronitrile),! , 2'-
7zobis(4-methoxy-2,4-dimethylpaleronitrile), 2,2'-azobis-(2-andinopropane) dichloride, superdensified benzoyl, potassium persulfate, ammonium persulfate, t -Butyl hydroperoxide, di-t-butylcumene peroxide and other well-known
Initiators for radical polymerization may be used. In addition, it is possible to add a polymerization degree regulator such as acetatealdehyde or alkyl mercaptan to the polymerization system.The polymerization reaction temperature is usually 5.
It can be selected from the range of 0°C to boiling point. Monomer reaction rate Fi,
It can be determined as appropriate depending on the purpose, such as economic efficiency and direct O adjustment of heavy metals. The amount of ON-alkoxymethylacrylic acid units in the copolymer is appropriately selected depending on the application and is not particularly limited, and a copolymer with any composition can be synthesized, but it is in the range of 0.05 to 10 mol-〇. In addition, in the case of solution polymerization, the degree of polymerization of the copolymer can be adjusted by adjusting the amount of methanol separated from the solvent and the amount of aldehyde.

There is no restriction on the degree of polymerization, and copolymers with a wide range of degrees of polymerization can be synthesized.
A range of .about.3600 is usually chosen.

If vinyl ester remains in the reaction solution after the completion of the reaction, it is necessary to separate and remove the vinyl ester by KFi distillation or the like. When the N-alkoxymethyl (meth)atalylamide monomer remains, it may be removed, and in many cases, there is no problem even if 11 is allowed to remain. Furthermore, in carrying out such polymerization, it is possible to copolymerize with these monomers in addition to vinyl ester and N-alkoxymethylacrylide. The unsaturated mass, the sword is ethylene,
Propylene, a-hexene, a-octene, etc. Oα-olefin ζ (meth)acrylic, crotonic acid, (anhydride)
! Unsaturated esters such as Rein #, Fumarken, Itacon, etc. or their alcoholic esters or their alkali salts; (
meth)acrylamide, N-methylolacryla(do, etc.) O-unsaturated amide ζ 2-acrylamido-2-methylpropanesulfonic acid-type takeso salt and other sulfonic group-containing monomers 1N-(2-dimethylainoethyl)acryla( Do.

Cationic group-containing monomeric alkyl vinyl ethers such as N-(3-dimethylalanoprobyA) methacrylic compounds; styrene; N-vinylindazole, N-vinyl-2
- Unsaturated imidazole tN-vinyl acedoelectrode, such as methyl (〆”zole rurui or its quaternary compound),
N-vinyl-N-methyl-altamide, N-vinyl-
N-methylformide, methyl-N-vinylcarba/
”-).

ethyl-N-vinylcarpame), t@rt-f? ON-vinyl or N-4 noprobe macrocompounds such as ru-N-vinyl carbamate, methyl-N-impropenyl carbamate, ethyl-N-4 soprobenyl carpamate), t@rt-phthyl-N-impropenyl carbamate, etc. It is also possible to produce a copolymer so that these monomer units coexist and polymerize so that 10 moles or less of these monomer units are present once in the copolymer.

The thus obtained copolymer is then subjected to the following reaction to saponify the p-vinyl ester moiety.The saponification reaction is usually advantageously carried out as a solution of the copolymer in alcohol, particularly in methanol. be. Not only anhydrous alcohols but also those containing a small amount of water may be used depending on the purpose, and an organic solvent such as methyl acetate or ethyl acetate may be optionally contained. As a saponification catalyst, water-based alkali metals such as sodium hydroxide and potassium hydroxide, alcoholades such as sodium methylate and potassium methylate, alkaline catalysts such as ammonia, or hostile catalysts such as salt* and sulfuric acid are used. can be used. Among these, it became clear during the investigation process of the present invention that when acidic catalysts are used, they are likely to be crosslinked and insolubilized when drying the saponification reaction product.For this reason, industrially, alkaline catalysts, especially water ridges, are preferred from the economic point of view. IIum is the OI of the present invention
Rice is also suitable. The silicification temperature l is usually determined from a range of 10 to sO<0>C. 1 under strong alkaline and acidic conditions
If left at a high temperature of 00°C or higher for a long period of time, it is undesirable because the bonds of ido groups or alkoxymethyl groups will gradually decompose. can be stably combined without virtually disassembling it. Through the saponification reaction, divinyl ester units are partially or elevatedly saponified and converted into vinyl alcohol units, but this conversion rate is higher than that of the resin 011! of the present invention. It can be set to any value depending on the purpose, but usually O! ! Specifically, it is preferable that the copolymer contains 99.95 to 70 mol of vinyl alcohol units and 2.9 mol of vinyl ester units. In addition, the content of N-alkoxy methyl (meth)acrylamide units is KO,0S-10 mol-
A range of is usually preferred. As the chain length of the alkyl group of the N-alkoxymethyl (meth)acrylicide used becomes longer, the modified lIl is increased and/or when the content of vinyl units of the N-alkoxymethyl (meth)acrylides used is II&-, the modified lIl is produced. The water solubility of PVA may be lowered, and if a water-soluble modified PVA is intended, it is necessary to adjust the content of N-alkoxymethyl (meth)acrylates and the content of vinyl acetate units. As the saponification reaction progresses, normal PVA
In the same way as in the case of , a white gel or precipitate IIIR@ is produced. It is industrially preferable to use the method. By crushing, washing and drying this as necessary, the modified PM copolymer is produced. A powder can be obtained by drying for the purpose of evaporating the solvent.

It does not affect the solubility of the resulting PVA within the range in which it is applied, but care must be taken as it will become partially cross-linked and insolubilized if it is left at high temperatures of 100°C or higher for a long time, but it is usually not necessary to leave it under such conditions. . The modified PVA copolymer used in the present invention can be stored and transported in the same way as general PVA, and many copolymers whose composition has been modified to be water-soluble are resistant to water when used with Fi. After dispersion, a uniform paste solution can be obtained by heating while stirring. When the content of N-alkoxymethylacrylic acid unit is high and/or when the content of vinyl ester units is high and the water solubility is low, it is necessary to mix water with alcohols such as methanol, ethanol, gropanol, butanol, etc. mixed $
1& or dimethyl sulfoxide can also be used as a vehicle.

The modified PVA copolymer used in the present invention looks similar to PVA at first glance, but it has a distinctive property of providing film strength that can withstand moldy boiling water by curing it under suitable conditions. It can be distinguished from PVA of $1 by. As for the dP nearing conditions, O2 such as sulfur, salt, tank weight, phosphorous iron, etc. is added to the modified PVA solution and the aqueous solution.
Using catalytic amounts of mineral acids, organic acids such as acetic acid, oxalic acid, tartaric acid, mineral salts such as aluminum sulfate, titanium ammonium sulfate, and ammonium chloride, or salts that produce Km substances when dried, Also, a method of heating and drying can be mentioned. The degree of S for crosslinking and waterproofing varies depending on the purpose, and can be adjusted by selecting the amount of contact, heating temperature, and heating time. Modified PVA containing 0.1 to 10 mol of one unit of N-alkoxymethyl(meth)acryl azide when considering providing a film resistant to boiling water.
For copolymers, the pH of the solution is 1 to 5, and the heating source is 1j6.
An example is a range of 0 to 160°C and a heating time of 30 seconds to 30 minutes.

Thus, the resin wire PVA with excellent water resistance obtained by the present invention
It is used in a variety of applications that take advantage of its cross-linked water resistance and machine blindness in addition to its ability to protect against water. For example, fiber agents, fiber processing agents, surface aging agents for paper, binders for pigment coating, and internal additives for paper making.

Improver for amino resin adhesive, emulsion stabilizer during emulsion polymerization, wall material for microcapsules, inorganic binder such as gypsum board, glass fiber, rock wool, cellic, photosensitive resin, ammonium chloride for suspension 1 mixture , films, sheet pipes, duplexes, molded products such as fibers, wood, paper,
Aluminum foil, plus) 1 The industrial significance of the present invention is great.

The present invention will be explained in detail below using examples. In addition, the following parts are part by weight, weight -
0 means 9%I Example: An N-methoxymethylacrylamide-nodal vinyl copolymer containing 8.87 N-methoxymethylacrylamide units is saponified to form 8.87 N-methoxymethylacrylamide units. 87 Ru, vinyl alcohol unit IN
A modified PVA with 1.4 mole-1 vinyl acetate units and 2.87 units and a polymerization degree of 2200 was obtained.

(fiQPVAAl) This strange aPVA0911 water $
A film of about sOμ in thickness was prepared by adding phosphorus to 11 [to give a total concentration of 1.6 and forming a film at 76° C. for 1 hour. This film was insoluble in cold water or boiled water.Example 2 A predetermined amount of 1N-1L acupuncture water** was added to a 9-aqueous solution of qualitative PVA shown in Table 1 and mixed at 20°C. After confirming the pH, film formation was carried out at 75° C. for 1 hour to create a film of modified PVA with a thickness of about 50 μm.

After heat-treating this film sample (100 x 100 fog) in a hot air dryer for a specified time, check the weight. If the film maintains its shape, take it out and calculate the weight after absolute drying. The elution loss of the film with boiling water was determined at a constant rate. The results are shown in Table 2.

For comparison, film formation was carried out without adding sulfur to an aqueous solution of modified PVA (Comparative Example 1).

The same true value was carried out using modified PVA (K/chemical & 9114 mole 1 polymerized & 178G) and the results are also shown in Table 2. Table 1 (Modified pvum) Table 2 Example 3 Modified Pvmu A3&! Add 2 parts of ammonium chloride powder to 100 parts of 609-water 111 and mix together, and form a film at 75°C for 1 hour under O conditions in the same manner as in Example 2 to create a film with a thickness of about 50μ. did. This film was treated in a hot air dryer at 150°C for 5 minutes, then immersed in boiling water for 10 minutes, and the elution loss of the film due to immersion was measured. The results are shown in Table 3. Table 3 Example 4 N-butoxymethylacrylamide units were saponified to yield 8.4 N-butoxymethylacrylamide units. moles, 91 vinyl alcohol units
．． Modified PVA containing 6 moles and having a metal content of 2250 was obtained. Modified PVA of 0ξ was not homogeneous in water and had the property of clumping into dumplings in boiling water, but completely dissolved in dimethyl sulfoxide. To 100 parts of a solution of this modified PVA in 151 dimethyl sulfate was added 5 parts of an IN-sulfuric acid aqueous solution.
After forming a film by applying rIL at 110° C. overnight, the resulting film was subjected to heat treatment at 150° C. for 3 minutes. This film does not change its shape even in boiling water and is insoluble, and even when immersed in 100' CIZ) dimethyl sulfoxide, the film does not change its shape and does not dissolve.
RiRa Co., Ltd. Representative Patent Attorney Honda Angry Procedural Amendments Commissioner of the Patent Office Kazuinu Wakasugi 1, Indication of Case Patent Application No. 178595 No. 1978 2 Wise Name Resin with Excellent Water Resistance (+08 + RiRa Co., Ltd. 11+14 ad/aself;========
shi;:ri;;;=======±:chimai te”'4 Ueno et al. Column a Contents of the amendment (1) [2,2'-Azobis-isobutyronitrile] in Lines 6-7 of Member 9 of the specification is deleted.

(2) No. 15j [@ Corrected to “ammonium titanium sulfate, ammonium Jt-acid, ammonium sulfate” in line 15.

Claims (1)

[Claims] (1) Formula (where R1 is a hydrogen atom or lower alkyl group) in the molecule
means a hydrogen atom or an alkyl group, respectively. ) A resin with excellent water resistance that is formed by removing the solvent from a polyvinyl alcohol kD@ solution containing copolymerized units shown in 0(1) Modified polyvinyl alcohol is %N-
The tv set forth in claim 111 is a saponified product of dimethyl aryl oxide and acetic acid-vinyl-O copolymer O.
m1ll. (@l [Polyvinyl alcohol is N-butoxymethylacrylamide, vinyl acetate, and O copolymer O
The resin described in Paragraph 1 of the Patent Requests Omm made of a saponified product. The resin according to claims 1 to 11 [K], wherein the ill solution is water**.