JP3433997B2 - Polysulfide-containing block copolymer, method for producing the same, and curable composition thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an isocyanate compound, an epoxide compound or a polyfunctional compound having a functional group capable of reacting with an isocyanate compound or an epoxide compound.
The present invention relates to a liquid block copolymer which is a high molecular weight cured product having good physical properties and a method for producing the same, and furthermore, the cured product has low tackiness (residual tack) and, when the cured product is applied, a plasticized film. The present invention relates to a curable composition suitable for a sealing material and the like, in which the transfer of an agent is small and the coating film is not softened (having good paint resistance).

[0002]

2. Description of the Related Art Polysulfide polymers containing two or more thiol groups in one molecule are widely used for sealing materials, paints, adhesives and the like. Above all, U.S. Pat.
The polysulfide polymer described in No. 6,963 has excellent oil resistance, chemical resistance, gas barrier properties and flexibility, and furthermore has no stickiness on the surface of the cured product, that is, there is no residual tack at all, and over a long period of time. It has been used for many years as a raw material for sealing materials because it has excellent properties that it is free from dirt and dust.

[0003] Polyacrylic multifunctional low molecular weight copolymers are easily cured by polyfunctional compounds such as isocyanates and epoxides, and have excellent weather resistance, coloring properties and durability. Widely used for Among them, an elastic sealant using a low molecular weight copolymer obtained by the method described in JP-B-53-6028 and JP-B-53-6029 (described in JP-B-63-11388)
Is particularly excellent in weather resistance, durability and paint resistance.
It is used as a liquid acrylic urethane sealant for joints that require a paint finish.

[0004]

However, the polysulfide polymer has a polysulfide bond in the molecule.
Since it has a structure of -S _x- (x = 1 to 5), it has high polarity and can use only a limited plasticizer. That is, since a general-purpose inexpensive plasticizer cannot be used, the cost increases when a compound such as a sealing material is formed. Further, since the viscosity is higher than the molecular weight of the polymer, it is necessary to add a large amount of a plasticizer in order to improve the workability of the compound. For this reason, when a paint is applied to a cured product of a sealing material made of a polysulfide polymer, there is a problem that a coating film is softened (poor paint resistance) due to leaching of a plasticizer.

Accordingly, the present inventors have already developed a polymer composition comprising a polysulfide polymer and a thiol group-containing polyether polymer, and have previously proposed it (Japanese Patent Laid-Open No.
3-134058, JP-A-4-7331 and JP-A-4-363325).
This polymer composition has excellent compatibility with general-purpose and inexpensive plasticizers, and is suitable for a sealing material. Further, since the viscosity is low, the amount of the plasticizer to be added can be reduced, and the paint resistance can be greatly improved. However, only a polyether having a structure different from that of polysulfide and forming a copolymer with polysulfide has been obtained so far. Not always enough.

The polyacrylic multifunctional low molecular weight copolymer becomes an acrylic urethane-based sealing material by using an isocyanate prepolymer as a curing agent, and becomes a good rubber elastic body, but remains on the cured product surface. There is a drawback that the tackiness is large and when used outdoors, dirt such as dust adheres and the appearance of joints deteriorates.

Accordingly, it is an object of the present invention to provide a polysulfide-containing composition which has excellent compatibility with a plasticizer, has a low viscosity, and is easily cured by a diisocyanate or the like to give a cured product having good weather resistance, coloring properties and durability. An object of the present invention is to provide a block copolymer and a method for producing the same.

Another object of the present invention is to provide a curable composition having good paint resistance and weather resistance and having no residual tack by using the polysulfide-containing block copolymer as a sealing material. It is to be.

[0009]

Means for Solving the Problems As a result of intensive studies in view of the above-mentioned object, the present inventors have found that when radically copolymerizing an unsaturated monomer, a polysulfide polymer in which all the terminals of the molecule are thiol groups is used. It has been found that the presence thereof allows the plasticizer not compatible with the polysulfide polymer to be compatible with the polysulfide polymer, and that a polysulfide-containing block copolymer which is an excellent cured product due to diisocyanate or the like can be obtained. In addition, it has been found that this cured product has excellent paint resistance and hardly any residual tack.
The present invention has been made based on the above.

That is, the polysulfide-containing block copolymer of the present invention comprises: (a) the following general formula (1):

Embedded image (Where x is an integer of 1 to 5, m is an integer of 1 to 50
is there. ) A polysal consisting of the structural unit (I)
And a (b) general formula (2):

Embedded image (Where ^Ra is a hydrogen atom or a methyl group, and ^Rb is a carbon atom
1 to 20 alkyl groups, or hydrogen atoms, or hydroxyl groups,
Amino group, carboxyl group, hydrolyzable silyl group
At least one functional group selected from the group consisting of oxy groups
And p represents the degree of polymerization. )
From a copolymer skeleton consisting of structural units (II)
Wherein the structural units (I) and the structural units (II) are alternately arranged.
A row of alternating block copolymers, wherein the structural unit (I
The copolymer skeleton comprising I) has the following general formula (3):

Embedded image (Where R ₁ is a hydrogen atom or a methyl group, and R ₂ is a carbon atom
1 to 20 alkyl groups. ) Structural unit
(II-1) and the following general formula (4):

Embedded image (Where R ₃ is a hydrogen atom or a methyl group, and R ₄ is a hydrogen atom
Hydroxyl or hydroxyl group, amino group, carboxyl group, hydrolysable
At least one selected from the group consisting of a silyl group and an epoxy group
Both are alkyl groups having one type of functional group. By)
Represented by the structural unit (II-2), the structural unit (I)
1 to 90% by weight of a polysulfide polymer skeleton consisting of
Containing and a copolymer comprising the structural unit (II)
Contains 99 to 10% by weight of skeleton, hydroxyl group, amino group in one molecule
Group, carboxyl group, hydrolyzable silyl group and epoxy
At least two functional groups selected from the group consisting of
And a molecular weight of 500 to 1,000,000 .

In the above polysulfide-containing block copolymer, the functional group of the general formula (4) is a hydroxyl group, an amino group,
At least one selected from the group consisting of
Species, so that a hydroxyl group, an amino group and a
At least a functional group selected from the group consisting of
It is preferable to have two.

The preparation method of the Po Risarufaido block copolymer of the present invention is represented by the following general formula (5):

Embedded image (Where R ¹ is a hydrogen atom or a methyl group, and R ² is an alkyl group having 1 to 20 carbon atoms), and one or more unsaturated monomers represented by the following general formula: ( 6 ):

Embedded image (Where R ³ is a hydrogen atom or a methyl group, and R ⁴ is a hydrogen atom or at least one functional group selected from the group consisting of a hydroxyl group, an amino group, a carboxyl group, a hydrolyzable silyl group and an epoxy group) Is an alkyl group having
When copolymerized with one or more unsaturated monomers represented by the following formula, HS (C ₂ H ₄ OCH ₂ OC ₂ H ₄ Sx) mC ₂ H ₄ OCH is used as a polysulfide polymer (a). ₂ OC ₂ H ₄ SH (where, x is an integer from 1 to 5, m is an integer of 1 to 50.) by in the presence of a polysulfide polymer represented, and wherein the reacting.

In the isocyanate-modified polysulfide-containing block copolymer of the present invention, the preferred polysulfide-containing block copolymer is preferably two or more per molecule.
Of polyisocyanate having isocyanate group
Compound-modified isocyanate-modified polysulfur
A block copolymer comprising the above-mentioned organic polyisomers.
The content of the cyanate compound (d) is the above-mentioned polysulfide.
About the same molar amount as the functional group in the containing block copolymer (c).
The functional group and the organic polyisocyanate compound
(d) Reaction with one isocyanate group in the molecule
And the organic polyisocyanate compound
The residual isocyanate group in the molecule of the product (d) is a terminal isocyanate
Characteristically non-crosslinked
And

The first curable composition of the present invention comprises a curable composition containing (c) the above-described preferred polysulfide-containing block copolymer and (e) a compound having two or more isocyanate groups in one molecule. A composition comprising the general formula
( 6 ) wherein the functional group is at least one selected from the group consisting of a hydroxyl group, an amino group and a carboxyl group.

The second curable composition of the present invention comprises (f) the above-mentioned isocyanate-modified polysulfide-containing block copolymer, and (g) a polymer having two or more thiol groups in one molecule. It is characterized by the following.

Hereinafter, the present invention will be described in detail. [1] polysulfide-containing block copolymer polysulfide-containing block copolymer of the present invention, in the main _{chain, (a) -C 2 H 4} OCH 2 OC 2 H 4 -S x - ( where
x is an integer of 1 to 5. ) And a (b) copolymer skeleton of one or more unsaturated monomers capable of radical polymerization.

In the above polysulfide-containing block copolymer, the polysulfide skeleton of (a) and the polymer skeleton of (b) are linked by a monosulfide bond. Such a structure can be obtained by allowing a polysulfide polymer having thiol groups at both terminals to exist as a chain transfer agent when radically polymerizing an unsaturated monomer. That is, the growing radical is stopped by hydrogen abstraction of the thiol group, and is obtained by the remaining polysulfide polymer radical further participating as a polymerization initiation radical. Since the above-mentioned polysulfide polymer is bifunctional, it has an arrangement in which (a) a skeleton is bonded to both ends of the skeleton.

The proportions are as follows: (a) 1-90% by weight of the skeleton and
(b) Ri skeleton 99-10 wt% der, in particular (a) backbone 5-60
% By weight and (b) the skeleton is preferably from 95 to 40% by weight. In addition, the molecular weight Ri 500 to 1,000,000 der, especially 800-5
Preferably it is 0,000. If it is less than 500, the cured product will have insufficient elasticity, and if it exceeds 1,000,000 , it will be difficult to mix it as a composition.

Specific examples of the (b) unsaturated monomer forming a skeleton include alkyl esters, alkyl vinyl esters and alkyl vinyl ethers of acrylic acid or methacrylic acid, acrylonitrile, methacrylonitrile,
Vinylpyrrolidone, acrylamide, methacrylamide, styrene and its homologues, conjugated diene compounds such as butadiene, chloroprene and isoprene, α-olefins such as ethylene and propylene, vinyl halides such as vinyl chloride and vinylidene chloride, etc. Is mentioned.

Among the above skeleton (b), the following general formula ( 5 ):

Embedded image (Where R ¹ is a hydrogen atom or a methyl group, and R ² is an alkyl group having 1 to 20 carbon atoms), and one or more unsaturated monomers represented by the following general formula: ( 6 ):

Embedded image (Where R ³ is a hydrogen atom or a methyl group, and R ⁴ is a hydrogen atom or at least one functional group selected from the group consisting of a hydroxyl group, an amino group, a carboxyl group, a hydrolyzable silyl group and an epoxy group) Is an alkyl group having
A polymer skeleton obtained by radical copolymerization of one or more unsaturated monomers represented by the following formula (1) is preferable. The polysulfide-containing block copolymer in this case is
It is necessary that one molecule has at least two functional groups selected from the group consisting of a hydroxyl group, an amino group, a carboxyl group, a hydrolyzable silyl group and an epoxy group.

One of the acrylic unsaturated monomers forming the above skeleton is an alkyl ester of acrylic acid or methacrylic acid represented by the above general formula ( 5 ), and one or more of these are used. I do. The alkyl group (R ² ) in the general formula ( 5 ) may be linear or branched. Specific examples of the alkyl group include ethyl, n-propyl, isopropyl, n-butyl, isobutyl, 1-ethylpropyl, 1-ethylpentyl, 2-ethylhexyl, decyl, dodecyl, and the like. If the number of carbon atoms is too large, the adhesiveness of the cured product is inferior.

The other acrylic unsaturated monomer forming the skeleton is an unsaturated monomer represented by the above general formula ( 6 ). Is 2
-Hydroxyethyl acrylate or methacrylate,
Examples include glycidyl acrylate or methacrylate, N-methylaminoethyl acrylate or methacrylate, acrylic acid, methacrylic acid, fumaric acid, γ-metharyloxypropyltrimethoxysilane, γ-metharyloxypropylmethyldimethoxysilane, and the like.

As described above, when (b) a skeleton composed of the above unsaturated monomer is used as the skeleton, (a) if the skeleton is less than 10% by weight, the cured product obtained by curing with an isocyanate group-containing compound or the like is used. The effect of improving residual tack is poor, and (b)
When the skeleton is less than 30% by weight, the effect of improving the paint resistance and compatibility with the plasticizer is poor.
(b) The skeleton is preferably 90 to 30% by weight.

[2] Method for Producing Polysulfide-Containing Block Copolymer As described above, the structure of the polysulfide-containing block copolymer of the present invention is such that thiol is added to both terminals at the time of radical polymerization of the unsaturated monomer. It is obtained by allowing a polysulfide polymer having a group to be present as a chain transfer agent. Particularly preferred as the polysulfide polymer having thiol groups at both ends is HS (C ₂ H ₄ OCH ₂ OC ₂ H ₄ S _x ) _m C ₂ H ₄ OCH ₂ OC
₂ H ₄ SH (where x is an integer of 1 to 5 and m is an integer of 1 to 50).

Preferred examples of such polysulfide polymers are described in US Pat. No. 2,466,953. The polysulfide polymer has fluidity at room temperature and preferably has a molecular weight of 300 to 20,000. If the molecular weight is less than 300, the proportion of the polysulfide skeleton in the block copolymer decreases, and if it exceeds 20,000, the reactivity of the terminal thiol group decreases, and the chain transfer reaction is not performed well, and the degree of polymerization cannot be adjusted. Particularly preferred molecular weights are between 400 and 10,000. The polysulfide polymer may have a trifunctional or higher functional branched structure, but all terminal groups need to be thiol groups.

On the other hand, the unsaturated monomers may be charged all at once before their polymerization, or may be partially charged first, and the remaining monomers may be gradually charged by a dropping method. The latter method is effective particularly when the heat of polymerization tends to be a problem, and a low molecular weight copolymer previously polymerized on a small scale or a plasticizer may be used instead of the solvent. This polymerization is preferably performed by a bulk polymerization method or a solution polymerization method. The polymerization conditions may be in accordance with the general conditions for acrylic radical copolymerization, and the temperature is preferably from -20 to
The temperature is 150 ° C., more preferably 40 to 100 ° C., and the reaction time is preferably 0.5 to 50 hours, more preferably 1 to 20 hours. Note that the end point of the polymerization reaction may be a time point at which heat generation completely disappears.

When the polysulfide-containing block copolymer having the above skeleton is produced, since the copolymerization in the skeleton is radical polymerization, a usual polymerization initiator may be used. Specific examples include benzoyl peroxide, azobisisobutyronitrile, cumene hydroperoxide, tertiary butyl hydroperoxide, persulfate, and a redox catalyst. Further, an initiator having a functional group such as 2,2′-azobis (2-cyanopropanol) and 2,2′-azobis (2-cyanopropylamine) may be used.

[3] Isocyanate-Modified Polysulfide-Containing Block Copolymer As another polysulfide-containing block copolymer of the present invention, there is an isocyanate-modified polysulfide-containing block copolymer. This isocyanate-modified polysulfide-containing block copolymer can be obtained by reacting a polysulfide-containing block copolymer (c) with an organic polyisocyanate compound (d). In this case, the polysulfide-containing block copolymer (c)
Is a compound having the above copolymer skeleton, wherein the functional group of the alkyl group (R ⁴ ) in the general formula ( 6 ) is at least one selected from the group consisting of a hydroxyl group, an amino group and a carboxyl group. It is.

On the other hand, the organic polyisocyanate compound (d) is a polyisocyanate monomer which is a usual polyurethane raw material, and specifically, tolylene diisocyanate,
Examples include diphenylmethane diisocyanate, polymethylene polyphenyl isocyanate (Kukud MDI), hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, and the like.

To react them, the isocyanate group of (d) is added to one equivalent of the functional group (at least one selected from the group consisting of hydroxyl group, amino group and carboxyl group) of (c). It needs to be adjusted to 1.2 to 4.0 equivalents. If the isocyanate group exceeds 4.0 equivalents, unreacted polyisocyanate monomer remains and 1.2
If the amount is less than the equivalent, the viscosity of the resulting modified product is high. Preferably, the amount is adjusted so that the isocyanate groups become 1.4 to 2.5 equivalents.

At this time, a reaction catalyst may be used to accelerate the reaction, and triethylamine, triethylenediamine, pentamethyldiethylenetriamine, N,
Tertiary amine catalysts such as N'-dimethylpiperazine, tetramethylguanidine and N-methylmorpholine, and organic metal catalysts such as dibutyltin diurarate, dibutyltin dimaleate and zinc octenoate are preferred. The amount of these catalysts added is 0.001 to 100 parts by weight of the polymer.
It is preferably from 1.0 to 1.0 part by weight, particularly preferably from 0.003 to 0.5 part by weight. In addition, since these reaction catalysts deteriorate the storage stability of the resulting modified product, it is preferable to extend the reaction time without using as much as possible.

[4] Curable Composition (1) First Curable Composition The first curable composition of the present invention comprises (c) a polysulfide-containing block copolymer and (e) one molecule per molecule. A compound having two or more isocyanate groups. (c) The polysulfide-containing block copolymer is the same as that in the above isocyanate-modified polysulfide-containing block copolymer, and the functional group of the alkyl group (R ⁴ ) in the general formula ( 6 ) is a hydroxyl group, an amino group, At least one selected from the group consisting of carboxyl groups.

On the other hand, (e) the compound having two or more isocyanate groups in one molecule includes the above-mentioned (d) organic polyisocyanate compound and (d) reaction of an active hydrogen compound with (d) organic polyisocyanate compound. The resulting urethane prepolymer is preferred. As active hydrogen compounds,
Hydroxyl-terminated polyester, polyvalent polyalkylene ether, hydroxyl-terminated polyurethane polymer, acrylic polyol having hydroxyl group introduced into acrylic copolymer, hydroxyl-terminated polybutadiene, polyvalent polythioether, polyacetal, aliphatic polyol, and thiol group in one molecule Alkanes, alkenes and aliphatic thiols containing alkylene thiols having two or more diamines, diamines containing aromatic, aliphatic and heterocyclic diamines, and mixtures thereof.

The mixing ratio of (c) the polysulfide-containing block copolymer and (e) the compound having two or more isocyanate groups in one molecule is such that the ratio of (e) to the active hydrogen-containing group in (c) is It is preferable that the molar ratio of isocyanate groups (isocyanate groups / active hydrogen-containing groups) is 0.5 to 4.0. If it is less than 0.5, the cured product does not have a sufficiently high molecular weight, and if it exceeds 4.0, the cured product becomes brittle. A particularly preferred molar ratio is between 0.7 and 3.0.

(2) Second curable composition The second curable composition of the present invention comprises (f) an isocyanate-modified polysulfide-containing block copolymer, and (g) two or more thiols in one molecule. And a polymer having a group. (f) The isocyanate-modified polysulfide-containing block copolymer is the same as [3]. (g) Examples of the polymer having two or more thiol groups in one molecule include the above-mentioned (a) a polysulfide polymer and (h) a polymer containing a polyether moiety and a polysulfide bond in a main chain and having a thiol group at a terminal. A polysulfide polyether polymer having a group, or a mixture of (a) and (h). In terms of compatibility with the plasticizer and workability,
(h) Polysulfide polyether polymers are preferred.

The preferred (h) polysulfide polyether polymer is (a)-(R ₁ O) _n- (where R ₁ is an alkylene group having 2 to 4 carbon atoms, and n is an integer of 6 to 200). And a polyether moiety represented by (b) -C ₂ H ₄
It contains a structural unit represented by OCH ₂ OC ₂ H ₄ S _x — and —CH ₂ CH (OH) CH ₂ —S _x — (where x is an integer of 1 to 5), and has at its terminal (c) - having _{C 2 H 4 OCH 2 OC 2} H 4 -SH and / or -CH ₂ CH (OH) thiol groups represented by CH ₂ -SH. Preferred examples of such polysulfide polyether polymers are described in JP-A-4-363325 and JP-A-4-73325.
No. 31.

The mixing ratio of (f) the isocyanate-modified polysulfide-containing block copolymer and (g) the polymer having two or more thiol groups in one molecule is (f) the active hydrogen-containing group in (g). It is preferred that the molar ratio of isocyanate groups in ()) (isocyanate groups / active hydrogen-containing groups) is 0.5 to 4.0. If it is less than 0.5, the cured product does not have a sufficiently high molecular weight, and if it exceeds 4.0, the cured product becomes brittle. A particularly preferred molar ratio is between 0.7 and 3.0.

(3) Additives The above-mentioned first and second curable compositions are further improved in economy, workability in applying the composition, physical properties after curing, and the like. For the purpose, fillers such as calcium carbonate, talc, clay, titanium oxide, silica and the like can be added. In addition, the curable composition of the present invention is compatible with inexpensive phthalate esters such as dioctyl phthalate (DOP) and diheptyl phthalate (DHP), which could not be used in the case of using only a polysulfide polymer. These can be added. Plasticizers such as chlorinated paraffin and hydrogenated terphenyl can also be added.

Further, in order to quickly and surely cure after application, an appropriate amount of a reaction catalyst between a group having active hydrogen and an isocyanate group may be added. As this reaction catalyst,
The same ones as those used for producing the above isocyanate-modified polysulfide-containing block copolymer can be used.

[0040]

The present invention will be described in more detail with reference to the following examples.

Example 1 To 200 g (1.56 mol) of n-butyl acrylate and 12.24 g (0.11 mol) of 2-hydroxyethyl acrylate, a polysulfide polymer (trade name: "Thiokol LP-3", manufactured by Toray Thiokol Co., Ltd.) Thiol group; 0.1 mol, number average molecular weight = 1000, thiol group content = 7.0% by weight, 25 ° C.
47.14 g was added and mixed, and 30% by weight of the mixture was charged into a reaction vessel.

After the mixture was purged with nitrogen while gently stirring, the temperature was raised to 60 ° C., 0.2 g of α, α-azobisisobutyronitrile (AIBN) was added, and the reactor was immersed in a bath. The bath temperature was raised to 70 ° C. over 30 minutes so that the temperature did not exceed 100 ° C., and the mixture was polymerized. After the fever had subsided, AI was added to the remaining 70% by weight of the mixture.
A mixture obtained by adding 0.3 g of BN and mixing the mixture was heated to a temperature of 80 ° C.
Using a dropping funnel, the mixture was dropped into the reaction vessel over 2 hours so as not to exceed ° C. After the completion of the dropwise addition, the polymerization was terminated when no heat generation was observed.

The obtained polysulfide-containing block copolymer was a homogeneous and transparent liquid. 25 ° C for this polymer
Viscosity is 100 poise and thiol group content is 0.03% by weight
It was below. In addition, when the molecular weight distribution of the obtained polymer was analyzed using gel permeation chromatography (GPC) under the following conditions, a single peak was obtained. Table 1 shows the molecular weight expected from the charged monomers and the result of the measured molecular weight.

GPC analysis conditions Column: G3000HxL + G2000HxL + G1000HxL, Tosoh Corporation
Solvent: tetrahydrofuran (THF) Column temperature: 30 ° C. Flow rate: 1.0 ml / min Detector: Differential refractive index detector, RI MODEL504, manufactured by GL Sciences Corporation

Example 2 To 600 g (4.68 mol) of n-butyl acrylate and 41.80 g (0.36 mol) of 2-hydroxyethyl acrylate, a polysulfide polymer (manufactured by Toray Thiokol Co., Ltd., trade name "Thiokol LP-3") was used. Thiol group; 0.3 mol, number average molecular weight = 1000, thiol group content = 7.0% by weight, 25 ° C.
(Viscosity = 12 poise) and added and mixed. 0.36 g of AIBN was added to 20% by weight of the obtained mixture, and polymerization was carried out in the same manner as in Example 1. After the heat generation became mild, a mixture obtained by adding 1.44 g of AIBN to 80% by weight of the remaining mixture was dropped into the reaction vessel, and polymerized in the same manner as in Example 1.

The obtained polysulfide-containing block copolymer was a homogeneous and transparent liquid. 25 ° C for this polymer
Viscosity is 120 poise and thiol group content is 0.03% by weight
It was below. Further, when the molecular weight distribution of the obtained polymer was analyzed using gel permeation chromatography (GPC) under the same conditions as in Example 1, a single peak was obtained. Table 1 shows the molecular weight expected from the charged monomers and the result of the measured molecular weight.

Example 3 150 g (1.17 mol) of n-butyl acrylate and 8.71 g (0.075 mol) of 2-hydroxyethyl acrylate and a polysulfide polymer (manufactured by Toray Thiokol Co., Ltd., trade name "thiocol LP-55", thiol) Group; 0.05 mol, number average molecular weight = 4500, thiol group content = 1.9% by weight, 25 ° C.
To 86.84 g of viscosity = 450 poise), add 45 g of toluene,
The whole amount was charged all at once into a reaction vessel. In a stream of nitrogen
After the temperature was raised to 60 ° C., 0.75 g of AIBN was added and the mixture was stirred for 1 hour. Raise the bath temperature to 70 ° C over a further 30 minutes,
The reaction was performed over time.

The obtained polysulfide-containing block copolymer was varnish-like and translucent. The thiol group content of this polymer was 0.07% by weight or less. Further, when the molecular weight distribution of the polymer was analyzed using gel permeation chromatography (GPC) under the same conditions as in Example 1, a single peak was obtained. Table 1 shows the molecular weight expected from the charged monomers and the result of the measured molecular weight.

Next, 20 g of the obtained polymer was mixed with isocyanurate of hexamethylene diisocyanate (trade name “N-3500”, manufactured by Sumitomo Bayer Urethane Co., Ltd.).
After mixing with 2 g and 0.004 g of di-n-butyltin dilaurate, the mixture was poured into a mold having a thickness of 5 mm and cured at 20 ° C. for 1 day to obtain a sheet-like cured product.

Example 4 150 g (1.17 mol) of n-butyl acrylate and 13.06 g (0.11 mol) of 2-hydroxyethyl acrylate and a polysulfide polymer (manufactured by Toray Thiokol Co., Ltd., trade name "thiocol LP-56", thiol) Group; 0.04 mol, number average molecular weight = 3000, thiol group content = 2.3% by weight, 25 ° C.
(Viscosity = 200 poise) To 53.80 g, 0.75 g of AIBN was added and mixed, and the whole amount was charged into a dropping funnel. On the other hand, 90 g of toluene was charged into a reaction vessel, the temperature was raised to 70 ° C. in a nitrogen stream, and the mixture was stirred while being dropped. Internal temperature
The whole amount was added dropwise over 3 hours so as not to exceed 90 ° C., and then the mixture was stirred for 2 hours while maintaining the bath temperature at 70 ° C.

The obtained polysulfide-containing block copolymer was varnish-like and translucent. The thiol group content of this polymer was 0.05% by weight or less. Further, when the molecular weight distribution of the polymer was analyzed using gel permeation chromatography (GPC) under the same conditions as in Example 1, a single peak was obtained. Table 1 shows the molecular weight expected from the charged monomers and the result of the measured molecular weight.

Then, 20 g of the obtained polymer was mixed with isocyanurate of hexamethylene diisocyanate (trade name “N-3500”, manufactured by Sumitomo Bayer Urethane Co., Ltd.).
5 g and 0.02 g of di-n-butyltin dilaurate,
After pouring into a 5mm thick mold and curing at 20 ° C for 1 day,
It became a sheet-like cured product.

[0053]                           Table 1 Example No. Expected molecular weight⁽¹⁾                    Polystyrene     Acrylic skeleton    Polysulfide skeleton        Converted molecular weight ⁽²⁾ Example 1 4000 1000 4500 Example 2 4000 1000 6100 Example 3 6000 4500 14600 Example 4 8000 3000 14600 Note) (1): molecular weight expected from the preparation (2): Polystyrene obtained from the peak top by GPC
Molecular weight

Example 5 The polymers obtained in Examples 1 and 2 and various plasticizers shown in Table 2 were mixed so that the weight ratio of polymer / plasticizer was 10/5, and the compatibility was adjusted. Examined. Table 2 shows the results.

Comparative Example 1 Polysulfide polymer (manufactured by Toray Thiokol Co., Ltd.)
The trade name "thiochol LP-55") and various plasticizers shown in Table 2 were mixed so that the weight ratio of polymer / plasticizer was 10/5, and the compatibility was examined. Table 2 shows the results.

Table 2 Example 5 Comparative Example 1 Example 1 Example 2 Polymer of Plasticizer Polymer Dibutyl phthalate (DBP) Uniform transparent Uniform transparent Uniform transparent butylbenzyl phthalate (BBP) Uniform transparent Uniform transparent Uniform transparent diheptyl phthalate (DHP) Uniform transparent Uniform transparent Two-phase separation Dioctyl phthalate (DOP) Uniform transparent Uniform transparent Two-phase separation

Example 6 The entire amount of the polymer obtained in Example 1 was placed in a reaction vessel, and after purging with nitrogen for 30 minutes, 18.34 g of tolylene diisocyanate was obtained.
(0.11 mol), the mixture was sealed, and the mixture was stirred at 80 ° C. for 6 hours to modify the hydroxyl group with isocyanate. Isocyanate group content in the obtained isocyanate modified product is 1.72
% By weight, and the viscosity at 25 ° C. was 376 poise.

Example 7 100 parts by weight of the polymer obtained in Example 2 were mixed with 50 parts by weight of dihexyl phthalate (plasticizer) and calcium carbonate (filler).
225 parts by weight of titanium oxide (filler) and 5 parts by weight of di-n-butyltin dilaurate as a curing catalyst.
Add 0.1 part by weight, knead with 3 rolls, 95 ℃ and 10
Dehydration was performed at 1 mmHg for 1 hour to obtain a base material. 13.87 parts by weight of a bifunctional urethane prepolymer (NCO group content = 3.76%) obtained by adding xylylene diisocyanate to bifunctional polypropylene glycol having an average molecular weight of 1000 was mixed with 100 parts by weight of the base material, and the mixture was formed into a 5 mm thick mold. It was poured into a sheet-shaped cured product. The obtained cured product was white. When the cured product was cured at 20 ° C. for 3 days, and then cured at 50 ° C. for 7 days, no foaming was observed.

Next, on the surface of the cured product, a paint containing vinyl chloride resin as a main component (“Vinibon” manufactured by Kansai Paint Co., Ltd.) and a paint containing polyacrylate as a main component (Kansai Paint Co., Ltd.) "Vini latex" and Daido Paint Co., Ltd. "Hekidyne"
After 30 days at 20 ° C., the state of each coating film was observed.
Table 3 shows the results.

Example 8 Dihexyl phthalate (plasticizer) was added to 100 parts by weight of a polysulfide polyether polymer (number average molecular weight = 3500, thiol group content = 2.0% by weight, viscosity at 25 ° C. = 70 poise).
50 parts by weight, 225 parts by weight of calcium carbonate (filler) and 5 parts by weight of titanium oxide (filler) were blended, and 0.01 part by weight of triethylenediamine was added as a curing catalyst, followed by kneading with a three-roll mill. Dehydration was performed at 10 mmHg for 1 hour to obtain a main agent. 100 parts by weight of this main ingredient and 39.31 parts by weight of the isocyanate-modified polysulfide polyacryl block copolymer obtained in Example 7 were mixed and poured into a mold having a thickness of 5 mm to obtain a sheet-like cured product. The obtained cured product was white. When the cured product was cured at 20 ° C. for 3 days, and then cured at 50 ° C. for 7 days, no foaming was observed. Further, the obtained sheet-shaped cured product was subjected to the same paint resistance test as in Example 7. Table 3 shows the results.

Comparative Example 2 Polysulfide polymer (manufactured by Toray Thiokol Co., Ltd.)
Combined with 100 parts by weight of brand name "thiochol LP-55"), 30 parts by weight of butylbenzyl phthalate (plasticizer), 180 parts by weight of calcium carbonate (filler) and 10 parts by weight of titanium oxide (filler) Obtained. To 100 parts by weight of the main agent, 7.5 parts by weight of lead oxide (oxidizing agent) and 2.5 parts by weight of chlorinated paraffin (plasticizer) were mixed and poured into a mold having a thickness of 5 mm to obtain a sheet-like cured product. The obtained cured product had a brown color. About the obtained sheet-shaped cured product, Example 7
A paint resistance test similar to that described above was performed. Table 3 shows the results.

Table 3 Paint name Example 7 Example 8 Comparative example 2 Vinibon No abnormality No abnormality Sticky Vinyl latex No abnormality No abnormality Sticky Hekidine No abnormality No abnormality No abnormality Sticky

Example 9 The residual tack of the sheet-like cured product obtained in Example 8 was examined with a finger. Furthermore, it was examined how the residual tack changes after 4 and 7 days by exposing the cured product outdoors. Table 4 shows the results.

Comparative Example 3 Using a commercially available two-component acrylic urethane sealant,
A sheet-like cured product similar to that of Example 8 was obtained. The remaining tack of the cured product was examined in the same manner as in Example 9. Table 4 shows the results
Shown in

[0065]

[0066]

As described above in detail, the polysulfide-containing block copolymer of the present invention has a polysulfide skeleton and a copolymer skeleton of an unsaturated monomer, and when only a polysulfide polymer is used, Inexpensive phthalate plasticizers that are incompatible with each other are compatible with each other and the viscosity of the polymer is low, so that the amount of the plasticizer used can be reduced. In addition, it is easily cured with diisocyanate or the like to give a cured product having good weather resistance, coloring properties and durability. Also, there is no softening of the coating film due to the migration of the plasticizer. Further, according to the production method of the present invention, a novel polysulfide-containing block copolymer can be obtained by copolymerizing a polymer of various acrylic unsaturated monomers with a polysulfide polymer.

Such a polysulfide-containing block copolymer includes a sealing material, a potting agent, an adhesive,
It is suitable for use in paints and the like.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ identification symbol FI C09D 157/06 C09D 157/06 C09K 3/10 C09K 3/10 F (58) Investigated field (Int.Cl. ⁷ , DB name) ) C08F 293/00

Claims (9)

(57) [Claims] (1) (a) The following general formula (1): (Where x is an integer of 1 to 5, m is an integer of 1 to 50
is there. ) A polysal consisting of the structural unit (I)
A sulfide polymer skeleton; and (b) the following general formula (2): (Where ^Ra is a hydrogen atom or a methyl group, and ^Rb is a carbon atom
1 to 20 alkyl groups, or hydrogen atoms, or hydroxyl groups,
Amino group, carboxyl group, hydrolyzable silyl group
At least one functional group selected from the group consisting of oxy groups
And p represents the degree of polymerization. )
From a copolymer skeleton consisting of structural units (II)
Wherein the structural units (I) and the structural units (II) are alternately arranged.
A row of alternating block copolymers, wherein the structural unit (I
The copolymer skeleton comprising I) is represented by the following general formula (3): (Where R ¹ is a hydrogen atom or a methyl group, and R ² is a carbon atom
1 to 20 alkyl groups. ) Structural unit
(II-1) and the following general formula (4): (Where R ³ is a hydrogen atom or a methyl group, and R ⁴ is a hydrogen atom
Hydroxyl or hydroxyl group, amino group, carboxyl group, hydrolysable
At least one selected from the group consisting of a silyl group and an epoxy group
Both are alkyl groups having one type of functional group. By)
Represented by the structural unit (II-2), the structural unit (I)
1 to 90% by weight of a polysulfide polymer skeleton consisting of
Containing and a copolymer comprising the structural unit (II)
Contains 99 to 10% by weight of skeleton, hydroxyl group, amino group in one molecule
Group, carboxyl group, hydrolyzable silyl group and epoxy
At least two functional groups selected from the group consisting of
A polysulfide-containing block copolymer having a molecular weight of 500 to 1,000,000. 2. A polysulfide-containing composition according to claim 1.
In the block copolymer, the functional group of the general formula (4) is
Select from the group consisting of hydroxyl, amino and carboxyl groups
At least one type of hydroxyl group
Group, amino group and carboxyl group
Characterized by having at least two functional groups
Sulfide-containing block copolymer. 3. The following general formula (5) : Wherein R ¹ is a hydrogen atom or a methyl group, and R ² is an alkyl group having 1 to 20 carbon atoms.
At least one kind of unsaturated monomer and the following general formula (6) : (Where R ³ is a hydrogen atom or a methyl group, and R ⁴ is a hydrogen atom or at least one functional group selected from the group consisting of a hydroxyl group, an amino group, a carboxyl group, a hydrolyzable silyl group and an epoxy group) And at least one unsaturated monomer represented by the formula: HS (C ₂ H ₄ OCH ₂ OC ₂ H ₄ Sx) mC ₂ H ₄ OCH ₂ OC ₂ H ₄ SH (where x is an integer of 1 to 5 and m is an integer of 1 to 50) in the presence and reaction of a polysulfide polymer represented by the formula:
Production method of a block copolymer containing a metal . 4. The polysulfide-containing block copolymer according to claim 2, wherein (c) the polysulfide-containing block copolymer is (d) two or more per molecule.
Organic polyisocyanate compound having a cyanate group
A modified isocyanate denaturation port Risarufaido block copolymer by, the organic Poriisoshia
The content of the nitrate compound (d) is the above-mentioned polysulfide content
It is almost equimolar to the functional group in the block copolymer (c),
The functional group and the organic polyisocyanate compound (d) component
By reacting with one isocyanate group in the polymer
Bound, and the organic polyisocyanate compound (d)
Residual isocyanate groups in the molecule are terminal isocyanate groups
Characterized by being substantially non-crosslinked
Isocyanate-modified polysulfide-containing block copolymer
Coalescing. 5. The isocyanate-modified polymer according to claim 4,
In the sulfide-containing block copolymer,
The organic polyisocyanate compound (d) has two
Isocyanate having a cyanate group
A modified polysulfide-containing block copolymer. 6. An isocyanate according to claim 4 or claim 5.
In the modified polysulfide-containing block copolymer,
Of the functional group and the organic polyisocyanate compound (d)
Bonds with isocyanate groups are urethane bonds and urea bonds
And at least one selected from the group consisting of acid amide binding
Isocyanate-modified polysal, characterized by being a seed
Fido-containing block copolymer. 7. A (c) polysulfide-containing block copolymer according to claim 2, cured, wherein the benzalkonium to containing a compound having a (e) 2 or more isocyanate groups in one molecule Mold composition. 8. A composition containing (f) an isocyanate-modified polysulfide-containing block copolymer according to any one of claims 4 to 6, and (g) a polymer having two or more thiol groups in one molecule. A curable composition comprising: 9. A compound represented by the following general formula (5): (Where R ¹ is a hydrogen atom or a methyl group, and R ² is a carbon atom
It is an alkyl group of Formulas 1 to 20. 1) or 2 represented by
At least one kind of unsaturated monomer and the following general formula (6): (However, R ³ is a hydrogen atom or a methyl group, and R ⁴ is hydroxyl
Group, amino group and carboxyl group
And an alkyl group having at least one functional group.
You. With one or more unsaturated monomers represented by
_{The, HS (C 2 H 4 OCH} 2 OC 2 H 4 Sx) mC 2 H 4 OCH 2 OC 2 H 4 SH ( where, x is an integer from 1 to 5, m is an integer from 1 to 50
is there. The presence of the polysulfide polymer represented by
Polysulfide-containing particles by copolymerization in the presence
A lock copolymer (c) was prepared, and
De-containing block copolymer (c), 2 or more in one molecule
Organic polyisocyanate compound having isocyanate group
Product (d) with the polysulfide-containing block copolymer
The organic polyisocyanate is equivalent to 1 equivalent of the functional group in the body.
The isocyanate group in the salt compound (d) is 1.2 to 4.0 equivalents.
Isocyanate characterized by reacting at a certain ratio
Method for producing modified polysulfide-containing block copolymer
Law.