JPS59179648A - Water-resistant composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. having excellent film-forming properties, film strength and water resistance, consisting of a modified PVA having silyl groups in the molecule and an inorg. material. CONSTITUTION:A copolymer of a vinyl ester (e.g. vinyl acetate) with 0.01- 10mol% of an olefinic unsaturated monomer contg. a silyl group of formula I or II (wherein R<1> is a 1-5C alkyl; R<2> is a 1-40C alkoxyl which may be substituted with an O-contg. substituent, acryloxyl; R<3> is H, methyl; R<4> is H, R<1>; R<5> is a 1-5C alkylene, a bivalent org. residue whose carbon atoms are bonded to each other through an O or N atoms; n is 0-4; m is 0-2) is saponified to obtain a modified PVA having a degree of saponification of 70- 100mol%, a degree of polymn. of 10-3,000 and silyl groups in the molecule. 99.5-5wt% inorg. material having a particle size of 0.05-200mmu (e.g. clay) is added to 0.5-95wt% (on a solid basis) soln. of said modified PVA dissolved in an alkali-contg. water.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a water-resistant composition, and more particularly to a water-resistant composition comprising a modified polyvinyl alcohol having a silyl group in the molecule and an inorganic substance.

Polyvinyl alcohol (hereinafter abbreviated as PVA) has been widely used as various binders, adhesives, and surface treatment glues, and is unrivaled by other glues in terms of film-forming properties and strength. It has been shown [11] to have excellent performance. However, PV
Since A is water-soluble, it has the disadvantage of low water resistance, and although various methods have been studied to improve this problem, the current situation is that none of them are satisfactory.

As a result of intensive studies aimed at overcoming the above-mentioned drawbacks of PVA, the present inventors found that modified PVA containing a silyl group in the molecule
It was discovered that a composition in which an inorganic substance is blended with the above material has extremely excellent water resistance, and the present invention was completed based on this finding.

The present invention will be explained in more detail below.

Modified P containing a silyl group in the molecule used in the present invention
VA may be any substance containing silicon in its molecule, but the silyl group contained in the molecule may be a reactive substituent such as an alkoxyl group, an acyloxyl group, a silanol group which is a hydrolyzate thereof, or a salt thereof. Those having the following are particularly preferably used.

Methods for producing such modified PVA include: (1) introducing a cysilyl group into PVA or a modified polyvinyl acetate containing a carboxyl group or a hydroxyl group by post-modification using a silylating agent; (2) a method of introducing a cysilyl group into PVA or a modified polyvinyl acetate containing a carboxyl group or a hydroxyl group; (1) A method of saponifying a polyvinyl ester having a silyl group at the terminal obtained by polymerizing a vinyl ester in the presence of a mercaptan having a silyl group. Can be mentioned.

In the method of post-modifying PVA or modified polyvinyl acetate using a silylating agent, for example, the silylating agent is added to an organic solvent that does not react with the silylating agent, such as benzene, toluene, xylene, hexane, heptane, ether, or acetone. Dissolve the powdered PVA or the above-mentioned modified polyvinyl acetate in the solution with stirring, and let it cool at room temperature to
The silylating agent and P at a temperature in the range of the boiling point of the silylating agent.
Silyl group-containing modified PV by reacting VA or the above-mentioned modified polyvinyl acetate, or by further saponifying the vinyl acetate unit with an alkali catalyst etc.
You can get A. Examples of silylating agents used in post-modification include organo 710 gensilanes such as trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, vinyltrichlorosilane, diphenyldichlorosilane, and triethylfluorosilane, trimethylacetoxysilane, and dimethyldiacetoxysilane. Organosilicon esters of silana, organoalkoxysilanes such as trimethylmethoxysilane and dimethyldimethoxysilane, orcassilanols such as trimethylsilanol and diethylsilanediol, aminoalkylsilanes such as N-aminoethelaminopropyltrimethoxysilane, and trimethylsilicon. Examples include organosilicon isocyanates such as incyanate. The rate of introduction of the silylating agent, that is, the degree of modification, can be arbitrarily adjusted by adjusting the amount of the silylating agent used and the reaction time. Further, the degree of polymerization and saponification of the obtained silyl group-containing modified PVA can be adjusted as desired by the degree of polymerization and saponification of the PVA used or the degree of polymerization and saponification reaction of the modified polyvinyl acetate.

In addition, in a method of saponifying a copolymer of a vinyl ester and an olefinically unsaturated monomer containing a silyl group, for example, the vinyl ester and the olefinically unsaturated monomer containing a silyl group are combined with a radical initiator in alcohol. A silyl group-containing modified PVA can be obtained by copolymerizing the copolymer using PVA and then saponifying the copolymer by adding an alkali or acid catalyst to the alcohol solution of the copolymer. Vinyl esters used in the above method include vinyl acetate, vinyl propionate, vinyl formate and the like, but vinyl acetate is preferred from a medical standpoint. Examples of the silyl group-containing olefinically unsaturated monomer used in the above method include vinylsilanes represented by the following formula (I) and (meth)acrylamide-alkylsilanes represented by (■).

Cost CHa −CH(CH2)n S 1(R2)am
(1) R' Rlm [where n is 0 to 4, m is 0 to 2, R1 is carbon number 1 to 5
alkyl group (methyl, ether, etc.), R2 has 1 carbon number
~40 alkoxyl group or acyloxyl group (herein, the alkoxyl group or acyloxyl group may have an oxygen-containing substituent), R3 is a hydrogen atom or a methyl group, H4 is a hydrogen atom or a carbon number of 1 to 5 The alkyl group R5 represents an alkylene group having 1 to 5 carbon atoms or a divalent organic residue in which consecutive carbon atoms are bonded to each other via oxygen or nitrogen. In addition, when two R1s exist in the same monomer, R1 may be the same,
They may be different. Furthermore, when two or more R2s exist in the same monomer, R2s may be the same or different.

Specific examples of vinylsilanes represented by formula (I) include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris-(β-methoxyethoxy)silane, vinyltriacetoxysilane, allyltrimethoxysilane, allyltriacetoxysilane, Vinylmethyldimethoxysilane, vinyldimethylmethoxysilane, vinylmethyljethoxysilane, vinyldimethylethoxysilane.

Vinylmethyldiacetoxysilane, vinyldimethylacetoxysilane, vinyldimethylethoxysilane, vinyltriisopropoxysilane, vinyltriptoxysilane, vinyltrihexyloxysilane, vinylmethoxydihexyloxysilane, vinyldimethoxyoctyloxysilane, vinylditoxy Octyloxysilane, vinyltrioctyloxysilane, vinylmethoxydioleyloxysilane, vinyldimethoxyoctyloxysilane, vinylmethoxydioleyloxysilane, vinyldimethoxyoctyloxysilane, and also general formula % formula %) (where R", m is the same as above, X represents 1 to 2o)
Examples include polyethylene glycolized vinylsilane represented by: Further, specific examples of the (meth)acrylamide-alkylsilane represented by formula (n) include:
3-(meth)acrylamide-propyltrimethoxysilane, 3-(meth)acrylamide-propyltriethoxysilane.

3-(meth)acrylamide-propyltri(β-methoxyethoxy)silane, 2-(meth)acrylamide-
2-Methylpropyltrimethoxysilane%2-(meth)
Acrylamido-2-methylethyltrimethoxysilane, N-(2-(meth)acrylamido-ethyl)-aminopropyltrimethoxysilane, 3-(meth)acrylamido-propyltriacetoxysilane, 2-(meth)
Acrylamide-ethyltrimethoxysilane, 1-(meth)acrylamide-methyltrimethoxysilane, 3-
(meth)acrylamido-propylmethyldimethoxysilane, 3-(meth)acrylamido-propyldimethylmethoxysilane, 3-(N-methyl-(meth)acrylamido)-propyltrimethoxysilane, 3. −(
(meth)acrylamidomethoxy)-3-hydroxypropyltrimethoxysilane, 3-((meth)acrylamidomethoxy)-propyltrimethoxysilane,
Dimethyl-3-(meth)acrylamide-propyl-3
-()rimethoxysilyl)-propylammonium chloride, dimethyl-2-(meth)acrylamide-2-
Examples include methylprobyl-3-Ct')methoxysilyl)propylammonium chloride.

In addition, when copolymerizing vinyl ester with an olefinically unsaturated monomer containing a silyl group in producing the modified PVA used in the present invention, it is possible to copolymerize with such monomers other than the above two components. and other unsaturated monomers, such as styrene, alkyl vinyl ethers, vinyl versatate, (meth)acrylamide, olefins such as ethylene, propylene, α-hexene, α-octene, (meth)acrylic acid, crotonic acid, (anhydrous ) Unsaturated acids such as maleic acid, fumaric acid, itaconic acid, and alkyl esters, alkali salts, 2-acrylamide
Sulfonic acid-containing monomers such as 2-methylpronosulfonic acid and their alkali salts, trimethyl-2-(1-(meth)acrylamide-trimethyl-3-(1-(meth)
Acrylamidopropyl) ammonium chloride, 1-
It is also possible to have a cationic monomer such as vinyl-2-methylimidazole and an imitated product present in a small proportion.

In addition, in a method for saponifying a polyvinyl ester having a silyl group at the end obtained by polymerizing a vinyl ester in the presence of a mercaptan having a silyl group, for example, when vinyl ester is polymerized using a radical initiator, A mercaptan having a silyl group is added to the polymerization system all at once, in parts, or continuously, so that the mercaptan having a silyl group is present in the polymerization system, and by chain transfer to the mercaptan, the polyvinyl ester has a cylindrical group at the terminal. After the polyvinyl ester is produced, a modified PVA having a silyl group can be obtained by saponifying the polyvinyl ester by adding an alkali or acid catalyst to the alcohol solution of the polyvinyl ester.

As the mercaptan having a silyl group used in this method, 3-(trimethoxysilyl)-propylmercaptan, 3-()ethoxysilyl)-propylmercaptan, etc. can be used. In producing modified PVA by this method, it is also possible to include a small proportion of an unsaturated monomer copolymerizable with the vinyl ester used in method (2).

In the above-mentioned three production methods of modified PVA containing a silyl group in the molecule used in the present invention, a copolymer of a vinyl ester and an olefinic unsaturated monomer containing a silyl group is saponified. Method and method of saponifying a polyvinyl ester having a silyl group at the end obtained by polymerizing a vinyl ester in the presence of a mercaptan having a silyl group has advantages in terms of ease of industrial production and homogeneity of the obtained modified PVA. It is preferably used in

Modified PV containing silyl group used in the present invention
The content of silyl groups in A, the degree of saponification, or the degree of polymerization are appropriately selected depending on the purpose and are not particularly limited. The effect of the silyl group is exhibited even in a relatively small content, and the monomer unit containing the silyl group is usually selected from the range of 0.01 to 10 mol, preferably 0.1 to 25 mol. The saponification degree is usually preferably in the range of 70 to 100 molar ratio. Further, the degree of polymerization is usually selected from the range of 10 to 3,000.

When dissolving the above-mentioned modified PVA used in the present invention in water, a uniform aqueous solution is usually prepared by adding an alkali such as sodium hydroxide in some cases and heating with stirring. Obtainable.

The inorganic substance used in the present invention preferably contains elements such as aluminum, silicon, magnesium, and calcium, and specifically includes clay, Merck, calcium carbonate, aluminum silicate, calcium silicate, silica, sand, and aluminum oxide. etc. Furthermore, water-soluble silicates such as water glass, water-soluble aluminum compounds such as aluminum sulfate and sodium aluminate, and water-soluble zirconium compounds such as zirconium ammonium carbonate may also be used, but modified polyvinyl containing silyl groups in the molecule may also be used. This is not the best method because it tends to increase the viscosity of the alcohol aqueous solution. For purposes of the present invention, water-insoluble inorganic particles are preferred. There are no particular restrictions on the particle size of the inorganic particles, and various types can be used depending on the application, but in the case of applications that require transparency and surface smoothness, particles with a small particle size are generally preferred, and are usually 0.05 to 0.05. 200mμ
is adopted, and for other uses, those with a large particle size are preferred.

In the composition of the present invention, the weight mixing ratio of the modified PVA containing a silyl group in the molecule and the inorganic substance is the former/the latter 0
．． 5/99.5~9515, more preferably 1/99~
It's 90/10. When the latter blending ratio is less than 5, the water resistance is insufficient, and when it exceeds 99.5, the strength of the composition decreases.

As mentioned above, the composition of the present invention must contain a modified PVA having a silyl group in its molecule and an inorganic substance, but it may also contain solvents, various additives, and other water-soluble substances depending on the purpose. This can be achieved by incorporating a polymer resin or an aqueous polymer dispersion. Water is preferably used as a solvent, but it can also be used in combination with various solvents such as alcohols, ketones, dimethylformamide, dimethyl sulfoxide, etc. Also, as additives (d), various antifoaming agents, various dispersants, etc. Examples include nonionic or anionic surfactants, silane coupling agents, and conditioning agents. Examples of water-soluble resins include cellulose derivatives such as carboxymethyl cellulose and hydroxyethyl cellulose, poly(meth)acrylic acid, and polyhydroxy(meth)acrylate. or its copolymer, polyacrylamide, etc. (meth)
Acrylic polymer, polyvinylpyrrolidone or its copolymer, carboxy group-containing modified PVA, sulfuric acid group-containing modified PVA, sulfonic acid group-containing modified PVA, phosphoric acid group-containing modified PVA, quaternary ammonium base-containing modified PVA1 modified amino group-containing Examples include PVA, PVA derivatives such as general PVA, etc. Furthermore, examples of polymeric aqueous dispersions include acrylic polymers and copolymers, ethylene-vinyl acetate copolymers, vinyl ester polymers and copolymers, and styrene-based polymers.
Examples include aqueous dispersions such as butadiene copolymers.

The composition of the present invention is dissolved or dispersed in water or water containing the above-mentioned organic solvent, and is preferably used as an aqueous dispersion.

The composition of the present invention has reactivity toward inorganic substances due to modified PVA having a silyl group, and this performance and film-forming property,
Taking advantage of its film strength and water resistance, it is effectively used as an adhesive or binder for inorganic or organic materials, a vehicle for paint, a treatment agent for inorganic or organic materials, such as a surface coating agent, and is also used for conventional water-soluble materials such as films and sheets. It is also used in applications where synthetic resins were used. Among these, the composition of the present invention has a particularly strong reactivity with inorganic substances, so it exhibits excellent adhesion to inorganic substances, and also exhibits excellent water resistance, so it can be used as a treatment agent for inorganic materials, such as cement and mortar. It is extremely useful as a surface treatment agent for inorganic materials.

Although the reason why the composition of the present invention has excellent film-forming properties, strong acid coating, and water resistance is not fully elucidated,
The vinyl ester unit or vinyl alcohol unit in the modified PVA having a silyl group in the molecule used in the composition of the present invention exhibits film-forming properties, and the silyl group bonded with an alkoxyl group or acyloxyl group or these Silanol groups or their salts, which are hydrolysates of It is presumed that the film exhibits film strength or water resistance.

The present invention will be explained in more detail with reference to Examples below.
The present invention is not limited thereby. Note that unless otherwise specified in the examples, the keys ``part'' and ``part'' represent the standard for the amount of M.Example 1 A copolymer of vinyltrimethoxysilane and vinyl acetate was saponified to convert the silyl group into a vinylsilane unit. Modified PVA containing 0.5 mol%, a saponification degree of vinyl acetate units of 99.2 mol, and a silyl group in the molecule with a polymerization degree of 1600.
I got it. This modified PVA is 2.5% relative to the modified PVA.
of modified PVA dissolved in water containing sodium hydroxide.
A 10cf6 water bath solution was prepared. 30 parts of clay slurry dispersed in water to a solid content of 30% was mixed with 100 parts of this aqueous solution, and this aqueous dispersion was cast to form a sheet-like product. The obtained sheet-like material was immersed in cold water, hot water (95℃
) was also insoluble.

Comparative Example 1 In place of the modified PVA used in Example 1, polymerization degree 17 was used.
A sheet-like product was obtained in the same manner as in Example 1 except that PVA having a 50% saponification degree of 98.5 mol was used. When this sheet-like material was immersed in water, it was redispersed into pieces.

Examples 2-4 In place of the clay used in Example 1, the following prefectures were used.

The same procedure as in Example 1 was conducted except that a homogenizer was used.

The obtained sheet-like material was also insoluble in cold water and hot water (95°C).

Material used in Example 2: White carbon (silica) Example 3: Calcium carbonate Example 4
: Calcium silicate Example 5 A copolymer of dimethyl-3-methacrylamidopropyl-3-trimethoxysilylpropylammonium chloride and vinyl acetate was saponified to convert the silyl group into 0125
Mole content 4T L s Degree of saponification of vinyl acetate unit 98
A modified PVA with a polymerization degree of 1,750 and a molarity of 5 was obtained. When the same procedure as in Example 1 was carried out using this modified PVA, the obtained sheet-like material was found to be insoluble in both cold water and hot water (95°C).

Example 6 A copolymer of hinyltriisobroboxysilane and am-vinyl was sonicly saponified to contain 0.3 mol% of silyl i'Q, with a degree of saponification of vinyl acetate units of 88 mol, and a degree of polymerization of 175.
0 silyl group-containing PVA was obtained. This modified PVA was dissolved in water to create a 10% water bath solution, and 100 parts of sand (Toyoura standard sand) and 100 parts of water were added to 50 parts of this aqueous solution to create a slurry. The resulting slurry was cast onto a slate to a dry solid content of 309/rrl and dried at room temperature for 3 days to form a film. A funnel to which a glass tube was connected was adhered onto the coating, and water permeability into the coating was measured while filling the glass tube with water so that the water level was always maintained at 1 m. The water permeability was 10 me/m'' in 15 days.

Comparative Example 2 The water permeability of the slate itself used in Example 6 was compared to Example 5.
When measured in the same manner as above, it was found to be 0 at 5000 I/G. Comparative Example 3 In place of the silica/silica group-containing modified PVA used in Example 5, PVA with a degree of polymerization of 1750 and a degree of saponification of 98.5 was used. The same procedure as in Example 5 was carried out except for using.

The water permeability was 5oo0mJ/bat.

Example 7 10% aqueous solution of modified PVA used in Example 1
A slurry of 100 parts of white carbon dispersed in water was added to one part to prepare an aqueous dispersion having a solid content of 10 parts. This aqueous dispersion was applied to a mortar plate with a surface size of 12 as a dry solid content of 5 ot/rr? A cotton cloth was placed thereon as a reinforcing agent and dried at room temperature for 2 days. After that, a cut with a width of 16 nm was made in the mortar film with a knife, and after immersing it in water at room temperature or water at 40°C for 3 days, it was peeled off at a peeling angle of 9 using an autograph (Model IM-100, manufactured by Rotsu Seisakusho).
The water-resistant adhesive strength was measured at 0° and a tensile speed of 500 Tm/min, and the results shown in Table 1 were obtained.

Comparative Example 4 The same procedure as in Example 7 was carried out except that the 10% aqueous solution of modified PVA used in Example 7 was used and white carbon was not used. The results are shown in Table 1.

Comparative Example 5 Instead of the modified PVA used in Example 7,
The same strain as in Example 7 was used except that ordinary unmodified PVA with a saponification degree of 98.5 and a saponification degree of 98.5 was used. The results are shown in Table 1.

Table 1 It can be seen from Table 1 that the water-resistant composition of the present invention has extremely excellent water resistance even under alkaline conditions.

Patent applicant: RiRashi Co., Ltd. Agent: No need for a patent attorney Ken

Claims (1)

[Scope of Claims] (1) A water-resistant composition comprising a modified polyvinyl alcohol having a silyl group in the molecule and an inorganic substance. (2) Water resistance according to claim 1, wherein the modified polyvinyl alcohol having a silyl group in the molecule is a saponified product of a copolymer of vinyl nystelt and an olefinically unsaturated monomer having a silyl group in the molecule. sexual composition. (8) The olefinically unsaturated monomer having a silyl group in the molecule has the following general formula (1) [where n is O-4. m is O~2, R1 carbon number is 1~5
The alkyl group R2 represents an alkoxyl group or an acyloxyl group having 1 to 4 carbon atoms (herein, the alkoxyl group and the acyloxyl group may have an acid "X f -containing substituent.") The water-resistant composition according to item 2, box 3ii of the claims, wherein (4) the olefinically unsaturated monomer having a silyl group in the molecule is represented by the general formula (II) 0 to 2, R1 is an alkyl group having 1 to 5 carbon atoms, R2 is an acyloxyl group having 1 to 40 carbon atoms, or an acyloxyl group (the alkoxyl); ), R3 is a hydrogen atom, a 1d methyl group, a H4σ hydrophilic atom, or a carbon number of 1
~5 alkyl group, R5 represents an alkylene group having 1 to 5 carbon atoms or a divalent organic residue in which a chain carbon atom is bonded to a phase via oxygen or nitrogen. ] The water-resistant composition according to claim 2, which is a monomer represented by the following. (5) The modified polyvinyl alcohol having a silyl group in the molecule is a saponified product of a polyvinyl ester having a silyl group at the end obtained by polymerizing a vinyl ester in the presence of a mercaptan having a silyl group. The water-resistant composition according to item 1. (6) The water-resistant composition according to claim 1, wherein the modified polyvinyl alcohol contains 0.01 to 10 moles of a monomer unit having a silyl group in the molecule. (γ) The weight blending ratio of modified polyvinyl alcohol having a silyl group in the molecule/inorganic substance is 0.5/99.5-95
15. The water-resistant composition according to claim 1, wherein the water-resistant composition is in the range of 15. (8) The water-resistant composition according to claim 1, wherein the composition is a composition for treating inorganic materials.