JPH0334766B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a polyol composition, particularly a polyol composition used for producing a cured polyurethane product. Among hydrocarbon compounds, those having hydroxyl groups can be used as materials for two-component polyurethane systems. Among them, hydrocarbon polyols with large hydroxyl equivalents are widely used because they have excellent properties such as elasticity, rubber adhesion, oil spreadability, waterproofness, and electrical insulation properties.In particular, polybutadiene polyols Paint pitting-resistant primer (Japanese Patent Application Laid-Open No. 1983
68176 Publication) Used for various purposes in a wide range of fields, including adhesive rubber (Japanese Patent Application Laid-Open No. 56-72066) Resin for sealing electronic components (Electronic Technology Research Institute Waraho 44 (3) p. 209) This is being considered. On the other hand, however, hydrocarbon polyols with a large hydroxyl equivalent have a high viscosity, and therefore have a serious drawback of extremely poor workability when handling them. In order to lower the viscosity, efforts have been made to use a considerable amount of solvent, or to use plasticizers and process oil in combination.
In the former case, there are problems such as deterioration of the working environment, danger of fire, and increase in cost, and in the case of the latter, there is a problem in that the physical properties of the cured product deteriorate. Therefore, a low viscosity hydroxyl group-containing compound is added to the above-mentioned high viscosity hydrocarbon polyol with a large hydroxyl equivalent.
For example, it is possible to mix polyether polyols and polyester polyols as reactive diluents, but hydrocarbon polyols with large hydroxyl equivalents have poor compatibility with general polyether polyols and polyester polyols, making it difficult to achieve the intended purpose. Unreachable. It has also been proposed to blend castor oil into a high viscosity hydrocarbon polyol (Japanese Patent Laid-Open No. 58-93717), but this also has limited solubility (depending on the type of hydrocarbon polymer). The viscosity of castor oil itself is about 10%, or at most 25% even if it dissolves at room temperature, although it varies depending on the
Partly because it is relatively high at 700 cps at 25°C, sufficient dilution and viscosity reduction effects cannot be obtained. Further, when a high viscosity hydrocarbon polyol is used alone as a urethane polyol, the mechanical properties (especially elongation) of the cured product are not sufficient.
Therefore, proposals have been made to improve elongation by blending polytetramethylene glycol with polybutadiene polyol (Japanese Unexamined Patent Application Publication No. 1985-1999).
No. 98220), in this case no viscosity reducing effect can be expected. From the above-mentioned background, it is well compatible with high viscosity hydrocarbon polyols with a large hydroxyl equivalent, lowers the viscosity, improves the elongation of the cured product, and does not impair other physical properties of the cured product. There is a strong desire to find substance. The present invention meets these demands. The polyol composition of the present invention comprises a high viscosity hydrocarbon polyol (A) and partially dehydrated or acylated castor oil (B). Partially dehydrated or acylated castor oil (B) is
It is extremely compatible with high-viscosity hydrocarbon polyol (A) and can greatly reduce its viscosity, which not only significantly improves workability when handling, but also greatly reduces the elongation of cured urethane products. can be improved. Particularly when using partially dehydrated castor oil, in addition to reducing viscosity and improving elongation,
Various physical properties such as tensile strength and tear strength of the cured product can also be improved. High viscosity hydrocarbon polyol (A) in the present invention
Examples include hydrocarbon polyols with a large hydroxyl equivalent (particularly hydrocarbon polyols with a hydroxyl value of 70 or less). Commercially available products include "PB R-45HT" manufactured by Idemitsu Petrochemical Co., Ltd., which is a polybutadiene-based polyol, "G-1000" manufactured by Nippon Soda Co., Ltd., which is a polybutadiene-based polyol,
An example is "Polytail HA" manufactured by Mitsubishi Chemical Industries, Ltd., which is a polyolefin polyol. Partially dehydrated or acylated castor oil (B) to be blended with such high viscosity hydrocarbon polyol (A)
Examples include the following: Partially dehydrated castor oil is first prepared by heating castor oil in the presence of an acidic catalyst such as sulfuric acid, phosphoric acid, p-toluenesulfonic acid, or acidic sulfate, similar to the production of conventional dehydrated castor oil. It can be obtained by If the degree of dehydration is too small, there is not much difference from castor oil itself, so the compatibility improvement effect and viscosity reduction effect will be poor. On the other hand, if the degree of dehydration is too large, the hydroxyl value will be too small, weakening the physical properties of the cured product. It is unsuitable as a urethane material. Therefore, in order to achieve the object of the present invention, it is desirable to control the degree of dehydration so that the hydroxyl value is within the range of 150 to 20, more preferably 140 to 35. That is, castor oil has a hydroxyl value of 160 and a viscosity of about 700 cps (25°C), but as the dehydration reaction progresses, the hydroxyl value and viscosity decrease as the reaction progresses. If the amount of catalyst is small, as the reaction is allowed to proceed, thermal polymerization will begin while the hydroxyl value remains above 20, and the viscosity will increase. On the other hand, when the amount of catalyst is large, the hydroxyl value increases to 75 to 5 and the viscosity decreases as the reaction progresses.
When the hydroxyl value decreases to about 110 to 140 cps (at 25°C) and heating is continued, the hydroxyl value does not decrease much after that, thermal polymerization begins, and the viscosity begins to increase. Therefore, the dehydration reaction can be controlled by a combination of the amount of catalyst, heating temperature and reaction time, and the conditions should be set so that the hydroxyl value of the reactant falls within the above range. Even if initial polymerization has begun, those having a sufficiently lower viscosity than castor oil and having a hydroxyl value within the above-mentioned range can be used for the purpose of the present invention. Partially acylated castor oil is produced by conventional acylation procedures. Among the acylations, acetylation is the most important, and the industrial limit is actually limited to this acetylation. As the acetylation method, a method of reacting with ketene or a method of reacting with glacial acetic acid can be adopted, but acetylation with acetic anhydride is industrially most advantageous. As in the case of dehydrated castor oil, if the degree of acylation is too small, the effect of improving compatibility and reducing the viscosity will be poor; on the other hand, if the degree of acylation is too large, the hydroxyl value will be too small, resulting in a cured product. It is desirable to control the degree of acylation so that the hydroxyl value of the acylated reaction product is within the range of 150 to 20, more preferably 140 to 35, since this may lead to a decrease in physical properties. The blending ratio of the above-mentioned high viscosity hydrocarbon polyol (A) and partially dehydrated or acylated castor oil (B) can be selected arbitrarily, but (A) 90 to 20% by weight, (B) 10% by weight, ~
It is desirable to choose from a range of 80% by weight. Particularly preferred ranges are (A) 85-35% by weight, (B) 15-65% by weight
It is. A polyol composition consisting of the above-mentioned high viscosity hydrocarbon polyol (A) and partially dehydrated or acylated castor oil (B) (in addition, this composition may contain other hydroxyl group-containing compounds (for example, castor oil) and plasticizers). ) is useful as a urethane polyol. That is, by reacting this polyol composition with a polyisocyanate, a cured product having excellent physical properties can be obtained. Such polyisocyanates include tolylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, xylylene diisocyanate, diphenylsulfone diisocyanate, triphenylmethane diisocyanate, hexamethylene diisocyanate, 3-
Methyl isocyanate-3,5,5-trimethylcyclohexyl isocyanate, ethyl 3-isocyanate-3,5,5-trimethylcyclohexyl isocyanate, ethyl 3-isocyanate-3,5,5-triethylcyclohexyl isocyanate, diphenylpropane diisocyanate, phenylene Diisocyanate, cyclohexylylene diisocyanate, 3,3'-diisocyanate dipropyl ether, triphenylmethane triisocyanate, diphenyl ether-4,
Polyisocyanates such as 4'-diisocyanate or their isocyanates are combined with phenols, oximes, imides, mercaptans, alcohols, ε-caprolactam, ethyleneimine, α-
Examples include those blocked with pyrrolidone, diethyl malonate, sodium bisulfite, boric acid, etc. The blending ratio of the polyol composition and polyisocyanate is preferably such that the isocyanate groups in the polyisocyanate are 0.8 to 1.4 equivalents relative to the total amount of hydroxyl groups in the polyol composition, since sufficient curing can be achieved. . Curing may be carried out slowly at low temperatures or may be accelerated by heating. The above formulations include fillers or pigments including talc, clay, calcium carbonate, baryta powder, silica powder, alumina, carbon black, titanium oxide, iron oxide, phosphorus compounds, halogen compounds,
Various additives such as flame retardants such as antimony oxide, antioxidants, anti-aging agents, and ultraviolet absorbers may be added as necessary. The polyol composition of the present invention can be used in casting compositions, impregnating compositions, coating agents, adhesives, paints, caulking materials, potting materials, sealants, foams, encapsulants, etc. by blending polyisocyanates therewith. It is useful for applications such as syringing materials, lining materials, packing materials, industrial rubber materials, and rocket fuel binders. Next, the present invention will be further explained with reference to Examples. Synthesis example of partially dehydrated castor oil 1-4 Castor oil (hydroxyl value 160, viscosity 700cps/25℃)
300 g and 0.15 g of acidic sodium sulfate were placed in a three-necked flask equipped with a thermometer and a stirrer, and heated under reduced pressure. The dehydration reaction begins at 165-190℃,
After that, the temperature gradually increased. The reaction was completed in 1 hour at 190 to 250°C, and after cooling, acid clay was added at 150°C for filter purification. Due to this dehydration reaction, the hydroxyl value
118, partially dehydrated castor oil with a viscosity of 400 cps/25°C was obtained. Partially dehydrated castor oil was also obtained in the same manner by changing the reaction conditions as shown in the following table. The above dehydration reaction conditions and properties of the product are shown in Table 1.

[Table] Synthesis example of partially acetylated castor oil 5-7 Castor oil (hydroxyl value 160, viscosity 700cps/25℃)
310 g and 11 g of acetic anhydride were placed in a flask equipped with a thermometer, stirrer, and reflux condenser.
Heating was continued to 120-150°C for approximately 2 hours. Then, the reflux condenser was replaced with a distillation condenser, and the temperature was gradually raised to recover by-product acetic acid and unreacted acetic anhydride by distillation. During this time, the degree of decompression was gradually increased using an aspirator. The temperature of the system is 200 after about 1 hour.
℃ was reached, this temperature was continued for 15 minutes and then cooled. This acetylation reaction results in a hydroxyl value of 140,
Partially acetylated castor oil with a viscosity of 550 cps/25°C and an acid value of 0.3 was obtained. Also, partially acetylated castor oil was obtained in the same manner by changing the amount of acetic anhydride as shown in the following table. Table 2 shows the above preparation conditions and product characteristics.

【table】

[Table] Compatibility test examples 1 to 5 with high viscosity hydrocarbon polyols, comparative example 1 "PBR-45HT" (A) manufactured by Idemitsu Petrochemical Co., Ltd., which is one of the high viscosity hydrocarbon polyols, 25℃
Or, after mixing the partially dehydrated or acetylated castor oil (B) obtained in Synthesis Examples 1, 2, 5, 6, or 7 above at 0°C in various ratios, leave it at the same temperature overnight. The compatibility was investigated. Here "PBR-45HT"
is a polybutadiene polyol having a number average molecular weight of 2800, a functional group number of 2.2 to 2.4, a hydroxyl value of 46, and an iodine value of 398. The results are shown in Table 3. In addition, Examples 1, 2,
3, 4, 5 are synthesis examples 1, 2, 5, 6, 7 in this order
When the partially dehydrated or acetylated castor oil obtained in 1 was mixed, Control Example 1 was a case where castor oil was mixed.

[Table] Example of reaction between polyol composition and polyisocyanate 6 The weight of polybutadiene polyol "PBR-45HT" manufactured by Idemitsu Petrochemical Co., Ltd. (A) and partially dehydrated castor oil obtained in Synthesis Example 1 (B) The mixture was mixed at a ratio of 7:3, and then carbodiimide-modified 4,4'-diphenylmethane diisocyanate ("Millionate" manufactured by Nippon Polyurethane Industries, Ltd.) was added to the mixture.
MTL") was blended so that the NCO/OH equivalent ratio was 1.05, and after stirring for 2 minutes, it was immediately poured into a mold and cured at a temperature of 120°C for 1 hour to obtain a cured sheet with a thickness of 3 mm. Table 4 shows the viscosity of the mixture of (A) and (B) above and the physical properties of the cured sheet obtained above. Example 7 Polybutadiene polyol “PBR-45HT”
A cured sheet was obtained in the same manner as in Example 6, except that (A), the partially dehydrated castor oil obtained in Synthesis Example 2 (B), and castor oil were mixed in a weight ratio of 6:2:2. The results are shown in Table 4. Example 8 Polybutadiene polyol “PBR-45HT”
A cured sheet was obtained in the same manner as in Example 6, except that (A) and the partially dehydrated castor oil (B) obtained in Synthesis Example 3 were mixed at a weight ratio of 8:2. The results are shown in Table 4. Example 9 Polybutadiene polyol “PBR-45HT”
A cured sheet was obtained in the same manner as in Example 6, except that (A) and the partially dehydrated castor oil (B) obtained in Synthesis Example 4 were mixed at a weight ratio of 8:2. The results are shown in Table 4. Control example 2 Polybutadiene polyol “PBR-45HT”
Using (A) alone as the urethane polyol, "Millionate MTL" was blended, poured, and cured in the same manner as in Example 6 to obtain a cured sheet. The results are shown in Table 4.

[Table] Example 10 Polybutadiene polyol “PBR-45HT”
A cured sheet was obtained in the same manner as in Example 6, except that (A) and the partially acetylated castor oil (B) obtained in Synthesis Example 5 were mixed at a weight ratio of 7:3. Example 11 Polybutadiene polyol “PBR-45HT”
A cured sheet was obtained in the same manner as in Example 6, except that (A) and the partially acetylated castor oil (B) obtained in Synthesis Example 5 were mixed at a weight ratio of 5:5. Example 12 Polybutadiene polyol “PBR-45HT”
A cured sheet was obtained in the same manner as in Example 6, except that (A) and the partially acetylated castor oil (B) obtained in Synthesis Example 6 were mixed at a weight ratio of 7:3. The results of Examples 10 to 12 are shown in Table 6. Furthermore, the results of Comparative Example 2 mentioned above are also shown in this Table 6.

[Table] In the above table, Examples 10 to 12 in which partially acetylated castor oil was mixed with polybutadiene polyol
Although the hardness and tensile strength of polybutadiene-based polyol are slightly lower than when polybutadiene-based polyol is used alone, the combined use of partially acetylated castor oil has a large effect of reducing viscosity and improving the elongation of the cured product, so the hardness and tensile strength of This more than makes up for the disadvantage in tensile strength.

Claims (1)

[Claims] 1. A polyol composition comprising a high viscosity hydrocarbon polyol (A) and partially dehydrated or acylated castor oil (B). 2 The blending ratio of high viscosity hydrocarbon polyol (A) and partially dehydrated or acylated castor oil (B) is
The composition according to claim 1, wherein (A) is 90 to 20% by weight and (B) is 10 to 80% by weight. 3. Claim 1, wherein the partially dehydrated or acylated castor oil (B) has a hydroxyl value of 150 to 20.
Compositions as described in Section.