JPS5912932A - Manufacture of silicon group-containing polymer - Google Patents

Abstract

PURPOSE:To obtain titled polymer which excellent durability and workability, by the addition reaction between a C-C unsaturated group-contg. polyoxyalkylene with its backbone chain composed of -R-O- recurring unit and a hydrolyzable group-contg. polysiloxane. CONSTITUTION:The objective polymer can be obtained by addition reaction, at ca. 30-150 deg.C, in the presence of a catalyst (pref. a platinum-based one such as chloroplatinic acid), between (A) a polyoxyalkylene with its backbone chain composed of -R-O- recurring unit [ R is 1-10C (substituted) hydrocarbon], also having, in one molecule, at least one C-C unsaturated group found between the end and side chain of the polyoxyalkylene ether, pref. of formula I (R' is 1-20C hydrocarbon; n and n' is each 0 or 1) and (B) a polysihoxane with its main chain consisting of -Si-O- siloxane bond, also having, in one molecule, at least one hydrolyzable group, (e.g. a cyclic pllysiloxane of formula II).

Description

[Detailed description of the invention] The present invention relates to a method for producing moisture-curable polymers.

In particular, silyl-terminated rubber has excellent properties such as excellent durability, low modulus and high elongation after curing, and in terms of curability, it has a fast curing speed and excellent workability. This invention relates to a method for producing polyether polymers.

The present inventor has already disclosed a method for obtaining a silyl-terminated polyether polymer by bonding a silicon hydride group containing a hydrolyzable group to a polyether polymer having an unsaturated group at the molecular end by an addition reaction. 50-156599 etc.

However, these polymers are not necessarily sufficient from the viewpoint of durability of cured products, which has been particularly demanded by the industry in recent years. Although this point has been considerably improved by blending, it is not satisfactory when aiming at a higher level. That is, HSi (R4)a (X)8-a (in the formula,
R4 is a monovalent organic group, X is a halogen group or a hydrolyzable group, and a is 0. In conventional silyl-terminated polymers obtained by adding the silane compound represented by 1 or 2), when a is 0, the curability is high, but the low modulus and high elongation properties are poor. On the other hand, when a is 2, the curing is extremely slow and it cannot be used. Further, when a is 1, although preferred curing speed and physical properties can be obtained, there is a problem in that it is difficult to obtain higher durability, low modulus, and high elongation properties. Especially when used as a sealant in areas where the adherend has a weak surface strength, such as lightweight concrete, the sealant due to slight expansion and contraction can easily peel off from the interface due to stress on the adherend interface. There's a problem. In an attempt to solve these problems, there is a method of lowering the modulus by using a large amount of plasticizer in the compound, but although this method can lower the modulus, it also causes a decrease in the strength at break, and the elongation rate decreases. On the contrary, it tends to deteriorate, and it also causes problems such as adhesion and sagging.

The present invention provides a novel method for producing a silyl-terminated polyoxyalkylene polyether polymer that overcomes these drawbacks. That is, the present invention provides at least one carbon-carbon unsaturated group in one molecule, preferably at the end of the molecule, having the formula: n has an unsaturated group represented by O or 1), and the main chain is essentially composed of chemically bonded repeating units represented by the formula -R〇- (R2 is a divalent hydrocarbon group) An unsaturated group-containing polyoxyalkylene polyether with a molecular weight of 300 to 15,000 and a hydrolyzable group-containing polysiloxane, preferably (wherein R8 is an organic group, and X is a halogen atom or a hydrolyzable group) , m is an integer from θ to 4, l is an integer from 1 to 5, Y
is a method for producing a silyl-terminated polymer characterized by carrying out an addition reaction with a cyclic organohydropolysiloxane represented by an organic group or a hydrolyzable group. It became possible to obtain a cured product with low modulus, high elongation, and fast curing.

The present invention will be explained in detail below.

In the present invention, the carbon-carbon unsaturated group is present at the terminal or side chain of the polyoxyalkylene ether, and typically has the formula +0-pR1), 7-C! It is represented by H=OH2.

In the above formula, R1 represents a hydrocarbon group having 1 to 20 carbon atoms, and n and n are 0 or 1. In terms of physical properties such as low modulus and high elongation, it is desirable that 70% or more of all polyether terminals are bonded with unsaturated groups. In -R-0-, R represents a hydrocarbon group or substituted hydrocarbon group having 1 to 10 carbon atoms, preferably 1 to 4 carbon atoms, such as -CH20H20H2C! Specific examples include H2O-.

In the polyether main chain, not only one type of these repeating units may be bonded, but also two or more types of repeating units may be bonded in a mixed form, but in particular, polyethers manufactured using propylene oxide as a raw material may be bonded together. Polyether that is Polyethers having such repeating units are produced using ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, etc. as raw materials by methods such as cationic polymerization and anionic polymerization.

During production, other ether bonds or other components may be introduced into the main chain within a range that does not impair the rubber elasticity of the cured product, for example, 10 mol % or less. In the present invention, -R-0- has substantially the above meaning.

Specifically, methods for introducing unsaturated groups include methods in which alkylene oxide is polymerized with caustic alkali and allyl alcohol or aliphatic polyhydric alcohol, and then reacted with an allyl halogen compound. The terminal group of a certain polyether is -(II!
M (M is Na or K) open/closed 53-184095) or an unsaturated bond due to an ester bond, carbonate bond, or urethane bond.

(Japanese Unexamined Patent Publication No. 54-6096).

The molecular weight is preferably 800 to 15,000, more preferably 5,000 to 10,000. If it is lower than this, it is difficult to obtain expected physical properties, and if it is higher than this, it becomes highly viscous and difficult to handle.

The polysiloxane used in the present invention is a compound having at least one, preferably two or more, hydrolyzable groups in one molecule, and whose main chain is represented by an 18i-0-siloxane bond. Among such compounds, the most preferred embodiment of the present invention is a compound of the general formula (where R4 and R5 are hydrogen or a substituted or unsubstituted monovalent organic group having 1 to 12 carbon atoms, X, Y, Z is a halogen atom, a hydrolyzable group, or a monovalent organic group having 1 to 12 carbon atoms; x, y, and 2 are 0 to 2;
m is an integer of 0 to 30, and l is an integer of 1 to 30. ) is a cyclic polysiloxane represented by In the above formula, the hydrolyzable group is one that is decomposed and condensed by moisture, such as an alkoxy group, an amino group, an aminooxy group, and a ketoximate group. Also, from a practical point of view, m = 0 to 4, e
-1 to 5 is optimal.

Specific examples of these compounds are shown below.

) These may be used alone or in a mixture of two or more, and include Bunmu, H-8i-(几')a(X)B-a (R4
,X.

(a is the same as before) may be used in combination. In reacting these cyclic organohydropolysiloxanes or hydrosilane compounds to terminally unsaturated polyoxyalkylene-ethyl, a conventional hydrosilylation catalyst is used, but a platinum-based catalyst is preferably used. In particular, compounds such as chloroplatinic acid, platinum-carbon, platinum chloride, and platinum olefin complexes give preferable results. In carrying out this reaction, any temperature from 30 to 150°C can be used, but it is particularly preferred to carry out the reaction at a temperature in the range from 50 to 120°C. A solvent may or may not be used, but if used, an inert solvent that does not have active hydrogen, such as ethers or hydrocarbons, is preferred.

The molar ratio of the cyclic organohydropolysiloxane to the number of moles of the terminal unsaturated group is preferably 0.5 to 1.5. Further, 0.5 to 1.2 is preferable. If it is less than 0.5, curing may be poor or the physical properties of the cured product will be adversely affected, and if it exceeds 1.5, it is economically disadvantageous.

In curing the silicon group-containing polyether of the present invention or a composition containing the polyether as an active ingredient, a silanol condensation catalyst may or may not be used, but it is preferable to use it. When using a condensation catalyst, use an alkyl group□
Tananoates; metal salts of carboxylic acids such as organosilicon di and dibutyltin maleate, dibutyltin phthalate, etc.; amine salts such as dibutylamine-2-ethylhexoate; and other acidic and basic catalysts known in the art. These silanol condensation catalysts are effectively used, but from the viewpoint of durability, the use of tin octylate gives the most favorable results. The amount of these condensation catalysts used is preferably 0 to 10% by weight based on the silicon-terminated polyether.

In the silyl-terminated polymer of the present invention, a trifunctional hydrolyzable silane compound is used as a crosslinking agent, if necessary. These compounds include MeSi(OCH3)B.

CH2=OH8i(OCHB)B, MeSi(OC
C! Examples include H3)B, CI(2=C!H8i-1, and partial hydrolysates thereof.

may be used in combination with a polyoxyalkylene ether polymer end-capped with (same as above).

When the polyether of the present invention is exposed to the atmosphere, it forms a three-dimensional network structure due to the action of moisture and hardens into a solid having rubber-like elasticity. Curing speed depends on atmospheric temperature, relative humidity,
Since it changes depending on the type of hydrolyzable group and the type of hydrolyzable group, it is necessary to carefully consider the type of hydrolyzable group when using it.

The silicon-terminated polyethers of this invention can be modified by incorporating various fillers. Fillers include reinforcing fillers such as silica, precipitated silica, anhydrous silicic acid, hydrated silicic acid and carbon black; calcium carbonate, magnesium carbonate, diatomaceous earth, calcined clay, clay, talc, titanium oxide, bentonite, Fillers such as organic bentonite, ferric oxide, zinc oxide, activated zinc white and shirasu balloons; fibrous fillers such as asbestos, glass fibers and filaments can be used. If you want to use these fillers to create a cured composition with high strength, you can use
A filler selected from silica, precipitated silica, anhydrous silicic acid, hydrated silicic acid, carphone black, surface-treated fine calcium carbonate, calcined clay, clay, activated zinc white, etc. is added in an amount of 1 to 100 parts by weight of silicon-terminated polyether. 100'
Favorable results can be obtained if used within the range of parts by weight, but
If you want to obtain a cured composition with low strength and high elongation,
Mainly titanium oxide, calcium carbonate, magnesium carbonate,
Fillers selected from talc, ferric oxide, zinc oxide, and shirasu balloons are added to silicon-terminated polyether 100.
Favorable results can be obtained if the amount is used in the range of 5 to 200 parts by weight. These fillers may be used alone or in combination of two or more types.

In the present invention, it is more effective to use a plasticizer in combination with a filler because the elongation of the cured product can be increased and a large amount of filler can be mixed.

Examples of the plasticizer include commonly used phthalate esters such as dioctyl phthalate, dibutyl phthalate, butylbenzyl phthalate; aliphatic esters such as dioctyl adipate, isothene succinate, dibutyl sebacate, etc. Dibasic acid esters; glycol esters such as diethylene glycol dibenzoate, pentaerythritol ester, etc.; aliphatic esters such as butyl oleate, methyl acetyl ricinoleate, etc.; tricresyl phosphate, trioctyl lysate, phosphoric acid Phosphate esters such as octyldiphenyl, epoxidized soybean oil, epoxy plasticizers such as benzyl epoxystearate, and plasticizers such as chlorinated paraffin may be used alone or in the form of a mixture of two or more. The amount of plasticizer is silicon-terminated polyether 1
Preferable results can be obtained when the amount is in the range of 0 to 100 parts by weight.

Fillers, plasticizers, and condensation catalysts are mainly used in the compounded composition containing silicon-terminated polyether as an active ingredient in the present invention, but adhesion promoters such as phenolic resins and epoxy resins, pigments, anti-aging agents, The optional use of additives such as ultraviolet absorbers is also included.

The composition of the present invention containing silicon-terminated polyether as an active ingredient can be either a one-part composition or a two-part composition. When used as a two-part composition,
For example, good results can be obtained by dividing the composition into a component consisting of the silicon-terminated polyether, filler and plasticizer and a component consisting of the filler, plasticizer and condensation catalyst, and mixing both components immediately before use. When used as a one-component composition,
If the silicon-terminated polyether, filler, plasticizer, and condensation catalyst are thoroughly dehydrated and dried, then mixed in the absence of moisture and stored in a cartridge, it can be used as a one-component composition with good storage safety. be.

The composition containing silicon-terminated polyether as an active ingredient obtained in the present invention is particularly useful as a one-component and two-component elastic/sealant, and can be used as a sealant for buildings, ships, automobiles, roads, etc. Furthermore, it can be used alone or with the aid of a primer to adhere to a wide range of substrates such as glass, porcelain, wood, metal, resin moldings, etc., so it can also be used in various types of sealing compositions and adhesive compositions.

Furthermore, it is also useful as a food packaging material, a casting comb material, a molding material, and a paint.

Examples are shown below.

Reference Example 1 320 g of polyoxybropyreciglycol with an average molecular weight of 3200 was placed in a pressure-resistant autoclave of 11 substituted with N2, and 40.8 g of powdered NaOH (purity 98%) was added.
After adding r, the temperature was raised to 60°C and stirred for 1 hour. Subsequently, 7.76 yr of bromochloromethane was added and the mixture was stirred at 60°C for 10 hours, and then 9.2 yr of allyl chloride was added and the reaction was further continued for 10 hours. After cooling, remove the contents and
Transferred to a 81 separable flask. After adding 1.54 n-hexane and stirring to make it homogeneous, 8 wt.
1.54% sulfuric acid water was added and stirred for 1 hour. After standing for 1 hour, the mixture was separated into two layers: a transparent hexane layer and an aqueous layer. At this time, the pH of the aqueous layer was 6 or less. The hexane layer was separated and taken out, and n-hexane was removed using an evaporator to obtain polyether (A) with an average molecular weight of 8,000 and 94% of the terminals converted to allyl ether.

100 gr of this allyl-terminated polyether was placed in a N2-substituted 0.51 pressure autoclave, and 0.2 (1 r) of a 10% solution of chloroplatinic acid in isopropyl alcohol was added, mixed uniformly, and then 2.0 yr of methyldimethoxyhydrosilane was added. The mixture was heated to 90°C and stirred for 4 hours.

Example 1 Allyl-terminated polyether (A) obtained in Reference Example 1 100
Put yr into a N2-substituted oi5'a pressure-resistant reaction vessel,
0% solution of chloroplatinic acid in isopropyl alcohol,
After adding 2 yr and mixing uniformly, the reaction was carried out at 90° C. for 4 hours.

As a result of GLC analysis (7), it was confirmed that almost the entire amount of the charged silane reacted with the terminal allyl group. 2 parts by weight of dibutyltin laurate were added to 100 parts by weight of this polymer, mixed uniformly, and left at room temperature for one day to obtain a rubber-like elastic body.

Example 2 In Example 1, the amount of silane charged was changed to 7. A terminal silane-modified polyether was obtained by carrying out the same operation as in Example 1 except that Ogr was used.

Two parts by weight of dibutyltin dilaurate were added to 100 parts by weight of this polymer, mixed uniformly, and left at room temperature for one day to obtain a rubber-like elastic body.

When analyzed by GLO, it was confirmed that almost the entire amount of the silane charged reacted with the allyl group at the terminal end of the polyether to form a terminal methyldimethoxysilyl-modified polyether CB).

Example 3 Allyl-terminated polyether (a) obtained in Reference Example 1 100y
Place r in a 0.51 pressure-resistant reaction vessel substituted with N2, and adjust the solubility of chloroplatinic acid in isopropyl alcohol to 0.2.
After adding gr and mixing uniformly, the temperature was raised to 90°C and stirred for 8 hours.

Analysis by GLO confirmed that almost all of the charged silane was bonded to the polyether end.

Example 4 Allyl-terminated polyether (4) obtained in Reference Example 1 100y
Place r in a 0.51 pressure-resistant reaction vessel substituted with N2 and add 0.2 g of a 10% solution of chloroplatinic acid in isopropyl alcohol.
After adding r and mixing uniformly, dimethoxyhydrosilane LOgr was added, the temperature was raised to 9°C, and the mixture was stirred for 2 hours.

GLC analysis confirmed that both hydrosilanes were almost completely bonded to the polyether terminals.

Example 5 A composition was prepared from the silyl-terminated polyether polymer obtained in Example 3.4 using three paint rolls according to the formulation shown below, and the following physical properties were obtained. As a comparative example, the results for the silyl-terminated polyether obtained in Reference Example 1 are also shown.

Table-1

Claims (4)

[Claims] (1) It has at least one carbon-carbon unsaturated group in one molecule, and the main chain is substantially of the formula R-0- (R is a divalent hydrocarbon group or a substituted hydrocarbon group) A method for producing a silicon group-containing polymer, which comprises carrying out an addition reaction between a polyoxyalkylene consisting of the repeating unit shown and a polysiloxane containing a hydrolyzable group. (2) The manufacturing method according to claim 1, wherein -11- is a hydrocarbon group having 1 to 10 carbon atoms or a substituted hydrocarbon group. (3) The manufacturing method according to claim 1, wherein the polysiloxane is a cyclic organopolysiloxane. (4) The manufacturing method according to claim 1, 2, or 8, wherein in the addition reaction, the polysiloxane is a mixture with hydrosilane.