JP2999797B2 - Hydrolyzable silyl group-terminated polymer and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a hydrolyzable silyl group terminal which gives a cured product having excellent durability such as heat resistance, water resistance and weather resistance and having excellent flexibility. Related to polymers.

[Conventional technology and problems] Conventionally, many proposals have been made for organic polymers having a hydrolyzable silyl group at a molecular terminal. Above all, the hydrolyzable silyl group-terminated polymer whose main chain is composed of polyoxyalkylene such as polyoxypropylene has excellent flexibility, is blended with various additives, and is used for applications such as sealing agents. ing. However, the durability (heat resistance, water resistance, weather resistance, etc.) of the cured product is still insufficient depending on the composition and use conditions, and improvement is desired.

Means for Solving the Problems The present invention has been made to solve the above-mentioned problems, and uses a liquid rubber having a functional group having a reactive hydrogen atom and / or a hydrogenated liquid rubber as an initiator. Wherein a group represented by the following formula (1) is introduced into a terminal of a modified polyol compound obtained by ring-opening polymerization of an alkylene oxide by 50% or more in terms of the number of all terminal groups. Modified polyol compound obtained by subjecting an alkylene oxide to ring-opening polymerization using a hydrolyzable silyl group-terminated polymer and a liquid rubber having a functional group having a reactive hydrogen atom and / or a hydrogenated liquid rubber as an initiator, At the end of a group represented by the following formula (1),
A method for producing a hydrolyzable silyl group-terminated polymer, characterized by introducing 50% or more.

Wherein R is a monovalent hydrocarbon group or a halogenated hydrocarbon group, X is a monovalent hydrolyzable group, R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms, a is 0, 1 or 2
It is.

The main chain of the polymer in the present invention contains residues of liquid rubber and / or hydrogenated liquid rubber, and contains a polyether chain (polyoxyalkylene chain). Liquid rubbers are butadiene, isoprene, chloroprene, 1,3-pentadiene,
A homopolymer or copolymer of a diene such as cyclopentanediene, or a copolymer of one or more of them with another copolymerizable monomer (eg, styrene, acrylonitrile, (meth) acrylate, etc.) at room temperature It is a polymer that is a liquid to a low melting point solid.

Liquid rubber usually has a functional group at the terminal. Examples of the functional group include a hydroxyl group, a carboxyl group, a mercapto group, a halogen atom and the like, and particularly those having a hydroxyl group or a carboxyl group are generally used. The hydrogenated liquid rubber is a hydride of this liquid rubber, and is one in which unsaturated groups in the liquid rubber are reduced or eliminated.

The (hydrogenated) liquid rubber having the polyether chain introduced therein is hereinafter referred to as a modified polyether compound. This modified polyether compound is a block copolymer in which oxyalkylene chains are introduced into both ends of the polymer chains of (hydrogenated) liquid rubber.
The oxyalkylene chain is formed by ring-opening polymerization of an alkylene oxide. That is, it is obtained by sequentially performing ring-opening polymerization of an alkylene oxide on a functional group having a reactive hydrogen atom such as a hydroxyl group, a carboxyl group, or a mercapto group among the above functional groups. The terminal group of this modified polyether compound is a hydroxyl group.

(Hydrogenated) liquid rubber has high hydrophobicity, so it is difficult to use an alkali catalyst (such as KOH) which is widely used as a polymerization catalyst for alkylene oxide. Therefore, it is preferable to use a double metal cyanide complex as the catalyst. Double metal cyanide complex catalysts are known as catalysts for alkylene oxide polymerization. Preferred catalysts are those containing zinc, such as cobalt zinc cyanide-glyme complex.

The polymerization reaction is carried out by adding an alkylene oxide to a mixture of a liquid rubber having a functional group having a reactive hydrogen atom such as a hydroxyl group or a carboxy group as an initiator and / or a hydrogenated liquid rubber and a composite metal cyanide complex under an arbitrary temperature condition. Can be added, but if necessary, the reaction can be carried out in the presence of a solvent.

Examples of usable solvents include hydrocarbon solvents, halogenated hydrocarbon solvents, and ether solvents.

Specific examples of the hydrocarbon solvent include hexane, cyclohexane, methylcyclohexane, benzene, toluene, xylene and the like.

Halogenated hydrocarbon solvents include methylene chloride,
Chloroform, carbon tetrachloride, trichloroethane, tetrachloroethane, chlorobenzene, dichlorobenzene and the like can be mentioned.

Examples of the ether solvent include diethyl ether, tetrahydrofuran, dioxane, glyme, diglyme and the like.

If necessary, these can be used alone or in any combination.

The polymerization initiator for obtaining the modified polyether compound,
A liquid rubber and / or a hydrogenated liquid rubber having a functional group having a reactive hydrogen atom such as a hydroxyl group or a carboxyl group.

Specific examples of the liquid rubber include liquid polybutadiene, liquid polychloroprene, liquid polyisoprene, liquid SBR,
Examples include, but are not limited to, liquid NBR.

Examples of the hydrogenated liquid rubber include hydrogenated liquid polybutadiene, hydrogenated liquid polychloroprene, hydrogenated liquid polyisoprene, hydrogenated liquid SBR, hydrogenated liquid NBR, and the like, but are not particularly limited thereto.

In particular, a hydrogenated liquid rubber such as a hydrogenated liquid polybutadiene, a hydrogenated liquid polychloroprene, a hydrogenated liquid polyisoprene is preferred because the cured product of the polymer of the present invention has a good balance between durability and flexibility.

As the alkylene oxide used for the polymerization to obtain the modified polyether compound, ethylene oxide, propylene oxide, butylene oxide, hexene oxide,
Examples include cyclohexene oxide and styrene oxide. In addition, alkyl glycidyl ethers such as methyl glycidyl ether, ethyl glycidyl ether, isopropyl glycidyl ether and butyl glycidyl ether, aryl glycidyl ethers such as phenyl glycidyl ether and cresyl glycidyl ether, and allyl glycidyl ether are also included. Propylene oxide and butylene oxide are preferred from the viewpoint of the flexibility and durability of the cured polymer.

The modified polyether compound contains residues of liquid rubber and / or hydrogenated liquid rubber in a molecule of 5 wt% to 80 wt%.
It is preferably contained, more preferably 10 wt% to 60 wt%. If the content of the residue of the liquid rubber and / or the hydrogenated liquid rubber exceeds this, the viscosity of the polymer is high and the flexibility of the cured product is insufficient. Insufficient.

Further, the molecular weight per hydroxyl group of the modified polyether compound is preferably 1,500 to 15,000, and 3,000 to 10,000.
More preferably, it is 00. If the molecular weight of the modified polyether compound exceeds this, the viscosity of the polymer is high and the durability of the cured product is insufficient. If the molecular weight is less than this, the flexibility of the cured product is insufficient.

The hydrolyzable silyl group-terminated polymer according to the present invention comprises 50% by number of groups represented by the following formula (1) based on all terminal groups.
And more preferably 70% or more.

However, R is a monovalent hydrocarbon group or a halogenated hydrocarbon group, and is preferably an alkyl group or a fluoroalkyl group having 8 or less, particularly 6 or less carbon atoms. More preferably,
It is a methyl group or an ethyl group. X is a monovalent hydrolyzable group such as a halogen atom, an alkoxy group, an acyloxy group, a carbamoyl group, an amino group, an aminooxy group,
And a ketoximate group. Among these, the carbon number of the hydrolyzable group having a carbon atom is preferably 6 or less, and particularly preferably 4 or less. Preferred hydrolyzable groups are alkoxy groups having 4 or less carbon atoms, particularly methoxy and ethoxy groups. R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms. a is 0, 1 or 2, and preferably 0 or 1.

The method for introducing the group represented by the formula (1) into the modified polyether compound is not particularly limited, but specifically, it can be introduced, for example, by the following method.

A method comprising reacting a modified polyether compound having an olefin group introduced into a terminal with a hydrosilyl compound represented by the following formula (2).

(Wherein R, X, and a are the same as described above). As a method for introducing an olefin group, for example, the terminal hydroxyl group of a modified polyether compound is reacted with a compound having an unsaturated group to form an ether bond, an ester, or the like. Bond, urethane bond, a method of bonding via a carbonate bond, or when polymerizing an alkylene oxide,
A method in which an olefin group-containing epoxy compound such as allyl glycidyl ether is added and copolymerized to introduce an olefin group into a side chain.

A method of reacting a compound represented by the following formula (3) with a terminal of a modified polyether compound.

(Wherein R ² is a divalent hydrocarbon group having 1 to 17 carbon atoms, and R, X and a are the same as above.) A polyisocyanate compound such as tolylene diisocyanate is reacted with the terminal of the modified polyether compound to obtain isocyanate. A method of reacting a W group of a silicon compound represented by the following formula (4) with the isocyanate group after forming a terminal group.

(Wherein W is an active hydrogen-containing group selected from a hydroxyl group, a carboxyl group, a mercapto group or an amino group (primary or secondary), and R, R ² , X and a are the same as described above). A method in which an olefin group is introduced into a terminal, and the olefin group is reacted with a mercapto group of the silicon compound represented by the above formula (4) wherein W is a mercapto group.

The hydrolyzable silyl group-terminated polymer of the present invention is three-dimensionally cured by a crosslinking reaction when it comes into contact with moisture. In the present invention, a modified polyether obtained by ring-opening polymerization of an alkylene oxide using a liquid rubber having a functional group having a reactive hydrogen atom such as a hydroxyl group or a carboxyl group as a main chain of the polymer and / or a hydrogenated liquid rubber as an initiator. It is important to use a compound, and it is only by this that the cured product can have both durability such as heat resistance, water resistance and weather resistance and flexibility.

[Example] Example 1 Hydrogenated polyisoprene-based polyol ^a) 250 g and toluene 50
g and a mixture of cobalt zinc cyanide-glyme complex ^d) 0.24 g were placed in a pressure-resistant reaction vessel, and propylene oxide was gradually added thereto while stirring at 100 ° C. under a nitrogen atmosphere to cause a reaction.
After the completion of the addition of 1000 g of propylene oxide, the mixture was further heated and stirred at 100 ° C. for 1 hour.

After cooling to 80 ° C., the solvent was distilled off under reduced pressure to obtain a modified polyether compound (A). The resulting modified polyether compound (A) had a hydroxyl value of 11.2 mgKOH / g.

Subsequently, 2.5 g of sodium hydride was added to 500 g of the modified polyether compound (A), and 100 g of the modified polyether compound was added under a nitrogen atmosphere in a pressure-resistant reaction vessel.
The mixture was heated and stirred for 1 hour. This was cooled to 50 ° C., 7.6 g of allyl chloride was added, and the mixture was stirred with heating for 6 hours. After cooling to room temperature, 1500 g of hexane and 5 g of magnesium silicate were added,
After stirring at room temperature for 30 minutes and filtration, hexane was distilled off under reduced pressure to obtain a modified polyether compound having a terminal olefin group (A '). The total degree of unsaturation of (A ′) was 0.20 meq / g.

The resulting terminal olefin group-containing modified polyether compound (A ') 500 g of methyl dimethoxy run 13.8 g, tetrahydrofuran 125 g, of chloroplatinic acid solution _{(1g H 2 PtCl 6 · 6H} 2
O / 10 ml of isopropyl alcohol) was added and heated at 90 ° C. for 8 hours in a pressure-resistant reaction vessel, and then unreacted methyldimethoxysilane was distilled off under reduced pressure to obtain a hydrolyzable silyl group-terminated polymer 1. Was.

Example 2 Hydrogenated polybutadiene-based polyol ^b) 250 g, tetrahydrofuran 50 g and cobalt zinc cyanide-glyme complex 0.2
8 g of the mixture is placed in a pressure-resistant reaction vessel at 100 ° C. under a nitrogen atmosphere.
And propylene oxide was gradually added with stirring to cause a reaction. After completion of the addition of 1300 g of propylene oxide, the mixture was further heated and stirred at 100 ° C. for 1 hour.

After cooling to 60 ° C., the solvent was distilled off under reduced pressure to obtain a modified polyether compound (B). The resulting modified polyether compound (B) was a pale yellow liquid having a hydroxyl value of 7.48 mgKOH / g.

Subsequently, 1.7 g of sodium hydride was added to 500 g of the modified polyether compound (B), and the mixture was placed in a pressure-resistant reaction vessel under a nitrogen atmosphere.
The mixture was stirred with heating at 0 ° C. for 1 hour. This was cooled to 50 ° C., 5.1 g of allyl chloride was added, and the mixture was heated and stirred for 6 hours. After cooling to room temperature, 1500 g of hexane and 5 g of magnesium silicate were added, and the mixture was stirred at room temperature for 30 minutes. After filtration, hexane was distilled off under reduced pressure to obtain a modified polyether compound containing an olefin group at the terminal (B '). Was. The total degree of unsaturation of (B ′) was 0.13 meq / g.

9.0 g of methyldimethoxysilane, 125 g of tetrahydrofuran and 0.01 ml of a chloroplatinic acid solution of the above concentration were added to 500 g of the modified polyether compound having a terminal olefin group (B '), and heated at 90 ° C. for 8 hours in a pressure-resistant reaction vessel. Thereafter, unreacted methyldimethoxysilane was distilled off under reduced pressure to obtain a hydrolyzable silyl group-terminated polymer 2.

Example 3 To 500 g of the modified polyether compound (A), isocyanatepropylmethyldimethoxysilane OCN (CH ₂ ) ₃ Si (CH ₃ )
18.8 g of (OCH ₃ ) ₂ and 0.015 g of dibutyltin dilaurate were added, and the reaction was continued at 50 ° C. under a nitrogen atmosphere until no isocyanate group was detected by IR to obtain a hydrolyzable silyl group-terminated polymer 3. .

Comparative Example 1 11.7 g of sodium hydride was added to 500 g of hydrogenated polyisoprene-based polyol ^a), and the mixture was heated and stirred in a pressure-resistant reactor at 100 ° C. for 1 hour under a nitrogen atmosphere. This was cooled to 59 ° C., 35.6 g of allyl chloride was added, and the mixture was stirred with heating for 6 hours. After cooling to room temperature, 1500 g of hexane and 5 g of magnesium silicate were added, and the mixture was stirred at room temperature for 30 minutes, filtered, and then hexane was distilled off under reduced pressure to introduce an olefin group into the terminal (C).
I got The total degree of unsaturation of (C) was 0.92 meq / g.

Subsequently, methyldimethoxysilane 6 was added to 500 g of the compound (C).
3.5 g, 125 g of tetrahydrofuran and 0.01 ml of a chloroplatinic acid solution of the above concentration were added, and the mixture was heated at 90 ° C. for 8 hours in a pressure-resistant reaction vessel, and then unreacted methyldimethoxysilane was distilled off under reduced pressure to give a hydrolyzable silyl group Terminal polymer 4 was obtained.

Comparative Example 2 For a polyoxypropylene diol having a hydroxyl value of 11.2 mgKOH / g and a total degree of unsaturation of 0.020 meq / g, a terminal olefin group was introduced by the method described in Comparative Example 1, and a silyl group was further introduced at the terminal. Thus, a hydrolyzable silyl group-terminated polymer 5 was obtained.

For the above hydrolyzable silyl group-terminated polymers 1 to 5, 1 wt% of dibutyltin dilaurate as a curing catalyst and 2 wt% of a stabilizer ^c) were added to prepare a sheet having a thickness of about 0.5 mm, and the physical properties and durability were measured. . The results are summarized in Table 1.
Note In Table 1, M ₅₀ 50% modulus (unit kg / c
m ² ), T _s is tensile strength (unit kg / cm ² ), E _a is elongation (unit%), and WOM is sunshine weatherometer.

a) Epohl manufactured by Idemitsu Petrochemical Co., Ltd. b) Polytail HA manufactured by Mitsubishi Kasei Co., Ltd. c) TINUVINB-5353 manufactured by Ciba-Gaikey Japan Co., Ltd. d) Prepared according to the method described in US Pat. .

[Effects of the Invention] The present invention provides a hydrolyzable silyl group-terminated polymer that gives a cured product having an excellent balance between durability and flexibility.

Claims (4)

(57) [Claims] 1. A modified polyol compound obtained by ring-opening polymerization of an alkylene oxide using a liquid rubber having a functional group having a reactive hydrogen atom and / or a hydrogenated liquid rubber as an initiator, the following formula (1) A hydrolyzable silyl group-terminated polymer obtained by introducing 50% or more of the group represented by the formula with respect to all terminal groups. Here, R is a monovalent hydrocarbon group or a halogenated hydrocarbon group, X is a monovalent hydrolyzable group, R ¹ is a hydrogen atom or
A is a hydrocarbon group having 1 to 10 carbon atoms and a is 0, 1 or 2; 2. The modified polyether compound is a modified polyether compound obtained by subjecting an alkylene oxide to ring-opening polymerization using the above liquid rubber and / or hydrogenated liquid rubber as an initiator using a double metal cyanide complex, Claim 1
The polymer according to the above. 3. The modified polyether compound contains a residue of the liquid rubber and / or hydrogenated liquid rubber in an amount of 5 wt% to 8 wt.
The polymer according to claim 1, which contains 0 wt% and has a molecular weight per hydroxyl group of 1,500 to 15,000. 4. 4. An alkylene oxide is subjected to ring-opening polymerization using a liquid rubber having a functional group having a reactive hydrogen atom and / or a hydrogenated liquid rubber as an initiator. The group represented by (1)
A method for producing a hydrolyzable silyl group-terminated polymer, characterized in that 50% or more of the polymer is introduced into all terminal groups by number. Here, R is a monovalent hydrocarbon group or a halogenated hydrocarbon group, X is a monovalent hydrolyzable group, R ¹ is a hydrogen atom or
A is a hydrocarbon group having 1 to 10 carbon atoms and a is 0, 1 or 2;