JPS60235839A - Polythioether polyol elastomer - Google Patents

Abstract

PURPOSE:The titled elastomer of a high Mooney viscosity, having excellent vulcanization crosslinking properties, and excellent oil and weathering resistance, containing a thiodiethanol component unit as the principal component, a specified diol component unit, and a xylylene glycol component unit. CONSTITUTION:The titled elastomer which has a Mooney viscosity ML1+4<100> of 10-60, consists of 50-95mol% thiodiethanol component unit (A), 0-50mol% 2-20C diol component unit (B), 1-20mol% unsaturated diol component unit (C) comprising a component unit of an unsaturated 4-20C aliphatic or alicyclic diol with methylene groups being at the alpha positions of its C-C unsaturated bonds, and 0.1-5mol% xylylene glycol component unit (D), and is made by the chain- lengthening, with component unit D, of a low-molecular-weight polythioether polyol elastomer, having a Mooney viscosity ML1+4<100> of 5 or less and the costitution of component units A, B, and C in a random arrangement.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a polythioether polyol elastomer having a dithioethanol component as a main constituent unit. More specifically, the present invention relates to a novel polythioether polyol elastomer that can be sulfur-cured and has excellent oil resistance, weather resistance, etc. of vulcanized molded products.

[Conventional technology]

Conventionally, polythioether polyol di-stomers obtained by copolymerizing a polycondensate of thiogetanol or a thiogetanol component as a main structural unit and an aliphatic diol component and/or an aromatic diol component have been subject to many prior art techniques. It has been proposed in the literature (for example, Japanese Patent Laid-Open No. 51-5
6858, JP 51-56859, JP 51-86557, JP 51-86590, JP 51-127196, JP 53-
49100, JP 56-54300, JP 53-115798, JP 53-1157
(See Publication No. 99, etc.).

These polythioether polyol elastomers have properties such as excellent oil resistance, heat resistance, and cold resistance. In order to obtain an improved rubber-like product, it is necessary to forcibly maintain a highly viscous reaction system for a long period of time, and when K does not produce vulcanizable rubber even if the reaction is continued. There are also
There were problems in manufacturing operations and economics.

[Problem that the invention seeks to solve]

The present inventors recognized that the conventional polythioether polyol elastomer having a thiogenol component as a main constituent unit was in the above-mentioned situation, and developed an improved polyester polyol elastomer that can complete the production of vulcanized and crosslinked molded products in a short time. As a result of studying the development of thioether polyol-based elastomers, we found that a new polymeric polythioether polyol-based elastomer is composed of thiogetanol component units as the main component, saturated diol component units, specific unsaturated diol component units, and xylylene glycol component units. The present invention was achieved by discovering that this is a combination.

[Summary of the invention]

To summarize the present invention, the present invention provides (50 to 95 mol% of thiodiethanol component units, m) 0 to 50 mol% of diol component units ranging from 2 to 20 carbon atoms, fc ) 1 to 20 moles of unsaturated diol component units consisting of unsaturated aliphatic or alicyclic diol component units having a carbon number in the range of 4 to 20 and in which the alpha position of the carbon-carbon unsaturated bond is a methylene group; %, and fd) consisting of xylylene glycol component units in the range of 0.1 to 5 mol%, and whose Mooney viscosity [jViL
;C+2] is in the range of 10 to 60, the structure is (
A low molecular weight polythioether polyol elastomer with a Mooney viscosity (1vIL', ♀!) of 5 or less consisting of a random arrangement of component units of a), (b) and fcl is a polythioether polyol elastomer whose chain is extended by the component units of (d). The gist is a chelated polyol-based elastomer.

[Means and effects for solving the problems] The composition of the polythioether polyol elastomer of the present invention is such that the thiogetanol component unit (a) is 50 to 95 mol%.
, 0 to 50 mol% of diol component units (b) having 2 to 20 carbon atoms, 4 to 20 carbon atoms, and the α-position of the carbon-carbon unsaturated bond is a methylene group. 1 to 20 mol% of unsaturated diol component units (C) consisting of certain unsaturated aliphatic or alicyclic diol component units and xylylene glycol component units (d)
is in the range of 0.1 to 5 mol%, and furthermore, the thioditanol component unit (a) is 50 to 90 mol%, the diol component unit (b) is 5 to 45 mol%, The unsaturated diol component unit (e) is 2 to 15 mol% and the xylylene glycol component unit (d
) is preferably in the range of 0.2 to 4 mol %. The content of the thiodiethanol component units fa) constituting the polythioether polyol elastomer is 95%.
If it is larger than 50 mol%, or if the content of the diol component unit (1) is larger than 50 mol%, the rubber-like properties of the polythioether polyol elastomer decrease. However, if the content of the unsaturated diol component unit (C1) exceeds 20 mol%, the heat aging resistance, weather resistance, etc. of the polythioether polyol elastomer will decrease. When this happens, the vulcanization rate and strength during vulcanization of the polythioether polyol elastomer become low.Furthermore, when the content of the xylylene glycol component unit (d) becomes greater than 5 mol%, the polythioether polyol The rubbery properties of the polythioether polyol elastomer begin to deteriorate, and when the amount is less than 0.1 mol%, the Mooney viscosity of the polythioether polyol elastomer increases and becomes brittle.

The Mooney viscosity (IViL: Y condyle of the polythioether polyol elastomer of the present invention is required to be in the range of 10 to 60, and more preferably in the range of 12 to 50. The polythioether polyol elastomer Vulcanization becomes difficult even if the Mooney viscosity of the polythioether polyol elastomer is greater than 60 or less than 10. The molded product is characterized by being insoluble in solvents such as petroleum ether, toluene, ethyl alcohol, and ASTM No. 3 oil, and having low swelling properties.Furthermore, the molded product obtained by sulfur vulcanization crosslinking of the polythioether polyol elastomer has the following characteristics: Point strength is usually 5
The range is 0/- or more, preferably 60/d or more.

The structure of the polythioether polyol elastomer of the present invention includes the thioglycol component unit (a), the diol component unit fbl, and the unsaturated diol component unit (C).
A polythioether polyol with a low molecular weight and a Mooney viscosity (yl'L:::) of 5 or less, preferably in the range of 0.1 to 5, which is obtained by polycondensation of each component unit arranged randomly. It is a polythioether polyol-based didistomer having a structure in which the elastomer is chain-elongated by being connected by the xylylene glycol component units (dl) and has an increased molecular weight.

In the molecular chain of the polythioether polyol elastomer, the thiogetanol component unit (a) forms a structural unit represented by the general formula [I] (OCH2CH2SCH2CH2-') [l], and the diol component The unit (b) has the general formula [■] moO-R''+[ll] [wherein R1 is a group consisting of two aliphatic diols, alicyclic diols, or aromatic diols having 2 to 20 carbon atoms. [indicates a residue excluding a hydroxyl group]], and the unsaturated diol component unit (C)
is the general formula [111]% formula %) [wherein R2 represents a residue obtained by removing two hydroxyl groups from an unsaturated aliphatic diol or unsaturated alicyclic diol having 4 to 20 carbon atoms] The xylylene glycol component unit (the mountain forms a structural unit represented by the general formula [IV] (-H2Cbe→-CH2+ [■]).

Further, the polythioether polyol elastomer may have a linear or branched structure, or may have a partially crosslinked structure.

The saturated diol component unit (b) constituting the polythioether polyol didistomer of the present invention has 2 to 20 carbon atoms. Preferably, it is a saturated diol component unit comprising 2 to 18 aliphatic, alicyclic or aromatic diol component units, excluding the xylylene glycol component. in particular,
Ethylene glycol, but[nopane-1,2-diol,
Propane-1,3-diol, aliphatic diols such as neopentyl glycol, cyclohexane-1,2-dimetatool, fuclohexane-1,4-dimetatool, 7
Alicyclic diols such as clobutane-1,2-dimethatol, hydroquinone, resorcinol, catechol, 2,2-
Bis(4-hydroxyphenyl)propane, 1.1-bis(4-hydroxyphenyl)ethane, bis(4-hydroxyphenyl)methane, 4.4'-dihydroxybiphenyl, 4.4'-dihydroxydiphenyl ether, 4.4'-dihydroxydiphenyl sulfide, 4
．． Examples include aromatic diols such as 4'-dihydroxybenzophenone and 4,4'-dihydroxydiphenylsulfone, and these diol components may be a mixture of two or more types. Among these diol components, the diol component consists of an aliphatic diol component unit having 2 to 2 carbon atoms, or a mixed component of the aliphatic diol component unit and an aromatic diol component unit having 6 to 18 carbon atoms. It is preferable to use a diol component whose main component is an aliphatic diol component unit.

The unsaturated diol component unit (e) constituting the polythioether polyol elastomer of the present invention has at least 4 to 20 carbon atoms, preferably 4 to 16 carbon atoms, at the α-position of a carbon-carbon unsaturated bond. An unsaturated diol component unit consisting of an unsaturated aliphatic diol component unit or an unsaturated alicyclic diol component unit having one methylene group. Specifically, monoallyl ether of trimethylolpropane, monoallyl ether of glycerin, 6-cyclohexene-1,1-dimetatool, 5-norbornene-2,2-dimetatool, 2-butene-1,
Examples include 4-diol and norbornenediol.

Among these unsaturated diol component units, monoallyl ether of trimethylolpropane and monoallyl ether of glycerin are preferred.

Specific examples of the xylylene glycol component unit fd) constituting the polythioether polyol elastomer of the present invention include para-xylylene glycol, metaxylylene glycol, orthoxylylene glycol, and the like.

The polythioether polyol elastomer of the present invention can be compounded with conventionally known compounding agents by ordinary rubber compounding techniques, and can be vulcanized with conventionally known vulcanizing agents. Specifically, carbon black, various pigments, vulcanization accelerators, lubricants, mold release agents, antioxidants, plasticizers, etc. can be used as compounding agents. Examples of the vulcanizing agent include sulfur and various peroxides. The proportions of these compounding agents and vulcanizing agents are within appropriate ranges.

Next, a method for producing the polythioether polyol elastomer of the present invention will be explained. The polythioether polyol elastomer of the present invention is a low molecular weight polythioether polyol elastomer composed of the thiogetanol component unit (a), the saturated diol component unit (b), and the unsaturated diol component unit (C). It is formed by copolycondensation reaction with xylylene glycol under dehydration conditions in the presence of an acidic catalyst.

In the low molecular weight polythioether polyol elastomer, the content of each component unit of the thiogetanol component unit fal, the saturated diol component unit (b), and the unsaturated diol component unit (C) is in the above-mentioned ratio. It is a low molecular weight polythioether polyol elastomer having a Mooney viscosity [based on 1viL7] of 5 or less, preferably in the range of 0.1 to 5.

The proportion of xylylene glycol used in the low molecular weight polythioether polyol elastomer is usually 0.1 to 5% by weight, preferably 0.0 to 100 parts by weight of the low molecular weight polythioether polyol elastomer.
．． The amount is in the range of 2 to 4% by weight, and is such a proportion that the composition of the xylylene glycol component units in the polythioether polyol elastomer to be produced is in the above-mentioned proportion.

As the acidic catalyst to be present during the polycondensation reaction, an acid having a pK of usually 8 or less, preferably 6 or less is used. Specific examples of the acidic catalyst include hydrochloric acid, sulfuric acid, p-toluenesulfonic acid, sulfamino acid, hyphric acid, fluorocarboxylic acid, phosphoric acid, and trialkyl phosphite. Among these acidic catalysts, sulfuric acid,
Preferred are p-toluenesulfonic acid, phosphorous acid, and the like.

The proportion of the acidic catalyst used is usually 0.001 to 2% by weight, preferably 0.005 to 1% by weight, based on the weight of the low molecular weight thioether polyol. If the acidic catalyst used in the production of the elastomer is present in the elastomer, it is not necessarily necessary to add it again.The temperature during the polycondensation reaction is usually 160 to 220°C,
Preferably, the temperature is in the range of 170 to 210° C., and the pressure is usually normal pressure and 5 to 760 μRH (y), preferably under normal pressure and reduced pressure of 10 to 300 μRH. By removing the water from the system, the polycondensation reaction proceeds. As the polycondensation reaction progresses, the polythioether polyol elastomer changes from a low molecular weight slimy state to a rubbery state with a high Mooney viscosity.

The polycondensation reaction is therefore carried out in a polymerization reactor equipped with a suitable high-shear stirrer.

Here, the low molecular weight polythioether polyol elastomer, which is a raw material for production, is copolymerized by dehydrating a mixture of monomers corresponding to the components (a) to C) in the presence of an acidic catalyst. Obtained by carrying out a condensation reaction. As the acidic catalyst, an acid having a pK of usually 7 or less, preferably 6 or less is used. Specific examples of the acidic catalyst include hydrochloric acid, sulfuric acid, p-)luenesulfonic acid, sulfamino acid, picric acid, fluoroacid, phosphoric acid, and trialkyl phosphite. Among these acidic catalysts, sulfuric acid, p-)luenesulfonic acid, phosphoric acid, and the like are preferred. The proportion of acidic catalyst used is usually 0.001 to 2% by weight based on the total amount of monomers.
Preferably it is in the range of 0.005 to 1% by weight.

The temperature during the polycondensation reaction is usually 160 to 220°C,
The temperature range is preferably from 170fK to 210°C, and the pressure is usually from 5 to 76 QimHp, preferably from 10 to 76011H,! ? The polycondensation reaction proceeds by removing the water produced by the reaction from the system. As the polycondensation reaction progresses, by interrupting the polycondensation reaction when the Mooney viscosity reaches the above range,
The low molecular weight polyether polyol elastomer is produced.

Next, the present invention will be specifically explained using examples.

〔Example〕

Example 1 (2) Production of polythioether polyol In a suitable glass container, a mixture of 4 ooy of thiogetanol, 75 g of diethylene glycol, 25 g of limethylolpropane monoallyl ether, and 0.2.9 g of sulfuric acid was heated at 195°C under a nitrogen atmosphere. Heat for about 8 hours. Next, the internal pressure was gradually reduced from 7601n+II'Hg to 2
The temperature was lowered to 00 tnmH9i, and the reaction was carried out for about 2 hours. Return the container to normal pressure and collect the polythioether polyol produced. The product has a Mooney value of 4 and is a very soft gum that can only be processed in a rubber mill. The composition of the produced polythioether polyol, determined from the analysis of the distillate of the reaction, is 73.6 mol% of thiogetanol component units, 22.2 mol% of diethyl glycol component units, and 4.4 mol% of trimethylolpropane monoallyl ether component units. %Met.

◎ 10 g of baraxylylene glycol was added to the product of polythioether polyol chain extension^, and the mixture was further heated at 195° C. under normal pressure for about 2 hours to extend the copolymer chain. The polythioether polyol elastomer thus obtained had a Mooney value of 28, and was a cam that could be milled. The composition of this gum was 22.5 mole % thiodiethanol component, 4.5 mole % trimethylolpropane monoallyl ether component units, and 2.2 mole % paraquinrylene glycol component units.

Comparative Example 1 A polythioether polyol produced in the same manner as in Example 1 (5) was allowed to react for 6 hours at 195 DEG C. and 150 to 100 Hg without adding paraxylylene glycol. The resulting cam Mooney value is 1.7
Met.

Example 2 Preparation of Polythioether Polyol In a conical mixer reactor, 30 g of Thiogetanol 6009.3-cyclohexane-1,1-dimetatool and 1.0 g of phosphorous acid were prepared.
Heat 75 g of the mixture at 195° C. under nitrogen atmosphere for about 5 hours. Next, the internal pressure is gradually reduced to 760℃ by evacuating it.
From 11111 Hg to about 380 XIHg, then more slowly to about 50 H9, and the temperature of the oil bath to 190°C. The heater was returned to normal pressure for about 2 hours, 70.9 of 4,4'-isoglopylidene bisphenol and 0.14.9 of sulfuric acid were added to the reaction mixture, and the reaction mixture was further heated at 190°C for about 1 hour. do.

The container is returned to normal pressure and the produced polythioether polyol is collected. The Mooney value of the product is 4.3, and it is a very soft gum that cannot be processed in a rubber mill. (b) Chain extension of polythioether polyol (5) There is no variation in the product. 12 g of silylene glycol was added, and the mixture was further reacted at 195°C under normal pressure for about 1 hour, and then further reacted for about 1 hour under reduced pressure of about 50111H&, to elongate the copolymer silver.

The extended chain polythioether polyol elastomer resulted in a millable gum with a Mooney value of 23. The composition of this gum is 86.1 mol% of thiogetanol component units, 0 mol% of 4.4'-isopropylide/bisphenol component units, and 6-cyclohexane-
It contained 4.9 mol % of 1,1-dimethatol component units and 2.0 mol % of paraxylylene glycol component units.

Comparative Example 2 A polythioether polyol was produced in the same manner as in Example 2 (c), and the reaction was continued at 190° C. for about 50 minutes without adding it para-xylylene glycol. As a result, a large amount of oily liquid was distilled out, and the product after 5 hours of reaction showed properties that were more similar to resin-like products than gum-like products.

Example 6 (5) Production of polythioether polyol Example 1 except that 25 g of glycerin monoallyl ether was used as a base for trimethylolpropane monoallyl ether.
A polythioether polyol was produced according to the procedure of 6). The product had a Mooney value of 4.5 and was a very soft rubber that could not be processed in a rubber mill.

(B) Chain extension of polythioether polyol (8)
To the product was added 8.1 g of baraxylylene glycol, and the mixture was reacted at 195° C. under normal pressure for about 30 minutes, and then further reacted for about 1 hour under reduced pressure for about 50 minutes to extend the copolymer silver. The polythioether polyol with extended chain had a Mooney value of 24.

The composition of this polythioether polyol is 71.6 mol% of thiogetanol component units, 21.1 mol% of diethyl glycol component units, 5.4 mol% of glycerol monoallyl ether component units, and 2.2 mol% of baraxylylene glycol component units. Met.

〔Effect of the invention〕

The polythioether polyol elastomer of the present invention is a high Mooney viscosity elastomer with excellent vulcanization and crosslinking properties, excellent oil resistance and weather resistance.

Applicant: Mitsui Oil Industry Co., Ltd. Agent Kazu Yamaguchi

Claims (1)

[Claims] (1) (a) 50 to 95 mol% of thiodiethanol component units, (b) O to 50 mol% of diol component units having 2 to 20 carbon atoms, (C) 4 carbon atoms. 1 to 20 mol% of unsaturated diol component units consisting of unsaturated aliphatic or alicyclic diol component units having a methylene group at the alpha position of the carbon-carbon unsaturated bond, and (d) It is composed of xylylene glycol component units in the range of 0.1 to 5 mol%, and its Mooney viscosity (ML::
A polythioether polyol-based elastomer in which : ] is 10y and L60, and the structure is (a)
, Φ) and (C), a low molecular weight polythioether polyol elastomer with a Mooney viscosity [ML, +4] or less than 5, consisting of a random arrangement of component units, is chain-extended by component units (d). Series elastomer 0