JPS59126459A - Room temperature curing elastomer composition - Google Patents

Abstract

PURPOSE:To obtain the titled composition having improved mechanical characteristics and weather resistance in high yield of polymerization from easily synthesizable raw materials, by compounding a curing catalyst to a copolymer obtained by the epoxy ring-opening copolymerization of a specific epoxide compound and a specific epoxy-containing silane. CONSTITUTION:The objective composition is prepared by compounding (A) 100pts.wt. of a copolymer obtained by compounding (i) an epoxy compound of formula I (X is univalent hydrocarbon group which may contain an ether O atom, or H) and (ii) an epoxy-containing silane of formula II (R<1> and R<2> are substituted or unsubstituted univalent hydrocarbon group; R<3> is bivalent hydrocarbon group; Y is univalent substituted hydrocarbon group which contains an oxirane oxygen and may contain an ether oxygen atom at the part bonded to R<3>; n is 0, 1 or 2) wherein the ratio of (ii) to (i) is 0.01-20mol%, preferably 0.05-2mol%, with (B) 0.01-20pts.wt. of a curing catalyst capable of curing the composition by accelerating the hydrolysis of -OR<2> group of the component A.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an elastomer composition that cures at room temperature under the action of moisture in the air.

Conventionally, as a room temperature curable elastomer composition, a compound having a polymer main chain having a polyoxine alkylene structure and a hydrolyzable functional group bonded to a silicon atom at the end of the molecular chain is used as a product, and the hydrolysis reaction is performed. Elastic body compositions containing curing accelerators that promote curing are known. Its main component compound is synthesized as follows.

That is, in Japanese Patent Publication No. 46-30711, r
- A hydrolyzable functional group (methoxy group in this case) bonded to a silicon atom is introduced by reacting a compound such as aminopropyltrimethoxysilane.
No. 98 discloses synthesis by reacting a polyoxyalkylene having an allyl ether group at the end of the molecule with a compound such as methyldichlorosilane, and then performing a hydroxylation/alkoxylation reaction.
In the publication, the compound is synthesized by reacting a polyoxyalkylene having an allyl group at the end of the molecule with a compound such as r-mercaptopropyltrimethoxysilane. 'However, in the above-mentioned known composition, the composition of the main components J'i
y. Because the polyoxyalkylene used as a raw material contains special reactive groups such as incyanate groups and allyl groups, poor yields and difficulties in purification during synthesis result in the final elastomer. There was a problem in that it led to unstable properties of the composition. Furthermore, the yield of the reaction for synthesizing the main component from polyoxyalkylene having an incyanate group or allyl group as a terminal group and an amount of hydrolyzable organosilicon compound corresponding to the amount of the terminal group also decreases due to the low concentration reaction. In addition, the steric hindrance of incyanate groups and allyl groups is low, which also causes the problem that the properties of the final elastomer composition become unstable. As mentioned above, conventionally known elastomer compositions based on raw materials and reactions with poor yields are not always satisfactory in terms of both low properties such as mechanical properties and weather resistance, and uneconomical performance. Ta.

An object of the present invention is to provide a room-temperature curable elastomer composition containing as a main component a polyoxyalkylene main chain copolymer synthesized from components different from those in conventional compositions. The object of the present invention is to provide a room-temperature-curable elastomer composition that has good raw material and synthesis yields and therefore has good mechanical properties.

That is, the present invention provides an epoxide compound represented by the formula (wherein, X represents a monovalent hydrocarbon group containing or not containing an ether oxygen atom or a hydrogen atom); is a different or similar monovalent substituted or unsubstituted hydrocarbon group, R3 is a divalent hydrocarbon group, Y contains an oxirane oxygen atom, and contains or does not contain an ether oxygen atom at the bonding site with R1 an epoxy group-containing silane represented by a substituted hydrocarbon group (n represents a number of 0, 1 or 2), in which the ratio of (group) to (a) is in the range of 0.01 to 20 mole 100 parts by weight of a copolymer ring-opened with epoxy groups, and (2) 0 of a curing catalyst that accelerates the hydrolysis reaction of the 10R2 group contained in the copolymer of (1) and cures it. .01 to 20 parts by weight of a room temperature curable elastomer composition.

The component (() in the present invention is for forming a polyoxyalkylene main chain in the copolymer (1), and is an epoxide compound represented by the general formula (υ). Specific examples thereof include: , ethylene oxide where the X group is a hydrogen atom, propylene oxide and butylene oxide where the X group is a monovalent hydrocarbon group, methyl where the X group is a monovalent hydrocarbon group containing an ether oxygen atom at the bonding site Glycidyl ether, ethyl glycidyl ether, propyl glycidyl ether, butyl glycidyl ether.

Examples include epoxide compounds such as phenyl glycidyl ether.

Component (b) is one that imparts a function of curing the composition of the present invention by interacting with moisture in the air by introducing a hydrolyzable -OR group into the copolymer of (1); B)
The -OR2 group is introduced into the copolymer (1) in good yield by copolymerization of the oxirane oxygen component and the epoxy group of the component (a). Such component (b) is represented by the general formula (2)
This is an epoxy group-containing silane represented by

The R group of component (b) is a methyl group or an ethyl group.

Alkyl groups such as propyl group, butyl group, hexyl group,
Examples include alkenyl groups such as vinyl groups and allyl groups, aryl groups such as phenyl groups, aralkyl groups such as styrenyl groups, monovalent substituted hydrocarbon groups such as chloromethyl groups, and 3,3.3-)lifluoropropyl groups. However, methyl, vinyl, and phenyl groups are advantageous from the viewpoint of ease of synthesis. The R group of component (b) is exemplified by the same monovalent hydrocarbon group as the above R1 group or an alkoxy-substituted hydrocarbon group, but because of its ease of handling and moderate reactivity,
Preferably, it is an alkyl group such as a methyl group, an ethyl group, or a propyl group, or a plucoxyalkyl group such as a methoxyethyl group or an ethoxyethyl group. Examples of the R3 group of component (b) include methylene group, ethylene group, propylene group, methylene group, hexylene group, p-phenylene group, etc., but propylene group is preferable from the viewpoint of stability of the compound. (B)
The component Y group is a monovalent carbon hydrogen group containing an oxirane oxygen atom and containing or not containing an ether oxygen atom at the bonding site with the R group, and includes an ethylene oxide group, a propylene oxide group, a butylene oxide group, and a cyclohexene group. Oxide groups such as oxide groups, glycidoxy groups, 3.
Examples include 4-oxycyclohexyl group. From the viewpoint of stability of the compound, r-crisitoxypropyl group and 3,4-oxycyclohexylethyl group are preferred as the Y-R- group.

From the above, specific examples of easy synthesis of component (b) include r-glycidoxypropyltriethoxysilane, r-glycidoxypropyltrimethoxysilane, r-ethyleneoxidepropyltrimethoxysilane, 3,4-oxycyclo Hexylethyltrimethoxysilane, and-glycidoxypropyltriethoxysilane, r-glycidoxypropyltriethoxysilane, γ-ethyleneoxypropyltri-1-toxysilane, 3,4-oxycyclohexylethyltriethoxysilane, methyl ( T-glycidoxyethyl)dimethoxysilane, methyl(r-glycidoxypropyl9dimethoxysilane, methyl(γ-ethyleneoxidepropyl)dimethoxysilane, methyl(3,
4-oxycyclohexylethyl dimethoxysilane,
Examples include methyl(r-glycidoxypropyl-shedoxinlan), methyl(γ-glycidoxypropyl)dipropoxysilane, and methyl(r-glycidoxypropyl9diserne ruboxysilane).

The epoxide compound (a) and the epoxy group-containing silane (b) have a ratio of (a) to (a) of 0.01 to 20.
A copolymer is obtained by blending the components in such a molar amount and carrying out ring-opening copolymerization of the epoxy groups, and this copolymer is used in the composition of the present invention. If the ratio of (a) to (a) is less than 0.01 molar ratio, the curability of the composition of the present invention will be significantly deteriorated,
Moreover, if it exceeds 20 mol%, the mechanical strength of the composition of the present invention after curing decreases, resulting in a brittle composition. In particular, the preferred blending ratio of (1) to (a) is in the range of 0.05 to 2 mol.

For the epoxy group ring-opening copolymerization of component (a) and (b) IFj, commonly used epoxy group-opening copolymerization is performed in an inert solvent such as toluene, xylene, dioxane, etc., which dissolves both components together, or in the absence of a solvent. Copolymerize using a ring polymerization catalyst. As an epoxy group-opening ring polymerization catalyst, AlCl, F
eCl3. Cationic polymerization catalysts such as Lewis acid catalysts such as BF3, anionic polymerization catalysts such as alkali metal hydroxides and alkali metal alkoxides, alkaline earth metal oxides,
Alkaline earth metal carbonates.

Alkaline earth metal alkoxide, AI Zn', M
Examples include coordination anion polymerization catalysts such as alkoxides such as Fe, and other catalysts, but copolymerization using coordination anion polymerization catalysts is preferred from the viewpoint of stability of the copolymer.
Alternatively, it is effective to use an alkoxide of zn.

Component (2) in the present invention promotes the hydrolysis of the one OR group directly bonded to the silicon atom of the component (1) introduced into the component (1), so that the composition of the present invention is substantially stable at room temperature. It is a catalyst for forming elastic bodies with organic titanate esters such as tetraalkyl titanates, triethanolamine titanates, and tetraisoglopenyloxytitanate, organic carboxylates such as lead, tin, iron, and zinc, and triethanolamine titanates. Aluminum alkoxides represented by isopropoxyaluminum, dialkyltin carboxylates such as dibutyltin diacetate, dibutyltin dilaurate, and dibutyltin dioctoate, amine compounds such as dimethylhexylamine, diethylhydroxylamine, and tetramethylguanidine, and their quaternary ammonium salts. etc. are exemplified. The above curing catalysts may be used alone or in combination. The amount of component (2) added is in the range of 0.01 to 20 parts by weight, preferably 0.1 to 10 parts by weight, per 100 parts by weight of component (1). If the amount added is less than 0.01 part by weight, the curing speed will be extremely slow, making it impractical; if it exceeds 20 parts by weight, separation, thickening, etc. will occur during the preparation of the composition, and the mechanical Characteristics deteriorate.

The elastomer composition of the present invention, which is composed of components (1) and (2) in the above-mentioned specific proportions, has the advantage of imparting appropriate viscosity or extrudability to the composition before curing, and providing suitable mechanical properties to the elastomer after curing. There is no problem in adding an inorganic filler for the purpose of imparting mechanical strength or hardness.

Examples of inorganic fillers include fumed silica, precipitated silica, silica aerogel, ground silica, diatomaceous earth, iron oxide, titanium oxide, calcium carbonate, alumina, and the like.

These inorganic fillers may be used alone or in combination of two or more. In addition, an inorganic filler whose surface has been treated with an organosilicon compound such as polydimethylsiloxane, octamethylcyclotetrasiloxane, or hexamethyldisilazane may also be used.Further, the composition of the present invention may contain an appropriate amount of a solvent, Pigments, thixotropic agents, viscosity-adjusting plasticizers, ultraviolet inhibitors,
It is permitted to add various additives such as heat resistance improvers and flame retardants.

The present invention provides a novel room temperature curable elastomer composition whose main component is a polyoxyalkylene main chain copolymer synthesized from components different from those in conventional compositions. Furthermore, according to the present invention, not only component (i) and (b) have good synthesis yields, but also the copolymerization of components (a) and (b) has a constant yield due to ring-opening copolymerization of epoxy groups. As a result, an elastic body with good mechanical properties and weather resistance could be cured at room temperature.

The elastic composition of the present invention can be applied to sealants, adhesives, sealants, coater ink materials, cast rubber materials, etc. by taking advantage of its good elastic properties.

The present invention will be specifically explained below with reference to Examples.

In addition, in the examples, parts mean parts by weight.

Example 1 Propylene oxide and 0.0% for propylene oxide.
A copolymer having a viscosity of 1200 cP at 20°C and an average molecular weight of 4500 was obtained by ring-opening copolymerization with 4 molar methyl (r-glycidoxypropyl 9 dimethoxysilane) as an All alkoxide medium. Copolymer 10
Add 80 parts of calcium carbonate with an average particle size of 5 μm to 0 parts,
After uniformly kneading, a tin compound shown in Table 1 was added as a catalyst to obtain a composition. This composition was cured at room temperature to obtain a comb-shaped elastic body, and after 7 days, its mechanical properties were evaluated according to JIS K6301, and the results are shown in Table 1.

Table 1 Example 2 7”o pyrene oxide and 0 for propylene oxide
A copolymer having a viscosity at 20"C of 2500 cP and an average molecular weight of 3800 was obtained by ring-opening copolymerization of 2 molar ratio of r-glycidoxypropyltrimethoxysilane using AI alkoxide as a catalyst. 40 parts of crushed silica with an average particle size of 5 μm and 6 parts of fumed silica surface-treated with polydimethylsiloxane were added to 100 parts of the combined mixture, and after uniformly kneading, the catalyst shown in Table 2 was added uniformly to form a composition. This composition was cured and evaluated in the same manner as in Example 1, and the results are shown in Table 2.

Table 2 Example 3 Propylene oxide 50ml, ethylene oxide 50ml
0.2 moles of methyl (l-glycidoxypropyl)jetoxysilane and AI alkoxide were used as a catalyst to perform ring-opening copolymerization, and the viscosity at 20°C was 6800 c.
p, a copolymer with an average molecular weight of 7200 was obtained, 15 parts of dioctyl phthalate and 60 parts of calcium carbonate with an average particle size of 2 μm were added to 100 parts of the obtained copolymer, and after uniformly kneading, the results shown in Table 6 were obtained. A composition was obtained by uniformly adding the curing catalyst shown. This composition was cured and evaluated in the same manner as in Example 1, and the results are shown in Table 6.

Table 6 Example 4 6.7 moles of dipropylene oxide, 33.3 moles of ethylene oxide, and 0.15 moles of IJ methoxysilane (3,4-oxycyclohexylethyl) were subjected to ring-opening copolymerization to form 20C ( A copolymer with a viscosity of 2800 cP at C and an average molecular weight of 4500 was obtained, and the obtained copolymer 10
After adding 15 parts of titanium oxide with an average particle size of 10 μm and 30 parts of zinc oxide with an average particle size of 5 μm to the powder and kneading them uniformly,
A composition was obtained by uniformly adding the curing catalyst shown in Table 4.

This composition was cured and evaluated in the same manner as in Example 1, and the results are shown in Table 4.

Table 4 Example 5 Ring-opening copolymerization of butyl glycidyl ether and 0.6 mol of phenyl (r-glycidoxyprobyl dimethoxysilane) to give 2
Viscosity at 0"C is 2500 cP.

A copolymer with an average molecular weight of 3800 was obtained, and 60 parts of calcium carbonate with an average particle size of 5 μm was added to 100 parts of the obtained copolymer, and after uniformly kneading, a curing catalyst shown in Table 5 was added uniformly. A composition was obtained. Example 1 for this composition
Table 5 shows the results of hardening and evaluation in the same manner as above.

Table 5 Patent applicant: Toshiba Silicone Corporation

Claims (1)

[Scope of Claims] 1(1)(a) An epoxide compound represented by the general formula (wherein X represents a monovalent hydrocarbon group containing or not containing an ether oxygen atom or a hydrogen atom; (b) General formula % formula %) (wherein, R and R are different or similar monovalent substituted or unsubstituted hydrocarbon groups, R is a divalent hydrocarbon group, Y contains an oxirane oxygen atom, and (a) an epoxy group-containing silane represented by a monovalent substituted hydrocarbon group containing or not containing an ether oxygen atom at the bonding site with R3, where n is a number of 0.1 or 2; 100 parts by weight of an Epoquine group open copolymerized copolymer, and (2) the copolymer of (1), blended so that the ratio of 1. A room-temperature-curable elastomer composition comprising 0.01 to 20 parts by weight of a curing catalyst that promotes the hydrolysis reaction of the one OR group contained in and cures.