JP3476001B2 - Flame retardant polyurethane resin composition - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a flame-retardant polyurethane resin composition, and more specifically, it is formed from a polyol having a low oxygen content and has heat resistance and moisture resistance having an isocyanurate ring in the molecule. The invention relates to a flame-retardant polyurethane resin composition having excellent properties.

[0002]

2. Description of the Related Art Conventionally, a polymer containing an atom such as phosphorus or halogen has been required since an LSI sealant, a circuit board housing case, a circuit board material, etc. are required to have flame resistance, heat resistance and moisture resistance. Is used. However, polymers containing phosphorus or halogen have a problem that harmful substances such as dioxins are generated when they are incinerated at the time of disposal, and therefore alternative materials have been demanded.

[0003]

In order to solve this problem, it can be considered to use a polyurethane resin composition having an isocyanurate ring, for example. Since the polyurethane resin composition having an isocyanurate ring has a network having a cyclic two-dimensional structure, it can be expected that flame retardancy and heat resistance are improved. Also, it can be incinerated or crushed for reuse when discarded,
It is also preferable in terms of environmental protection.

However, in the case of a polyurethane having an isocyanurate ring, isocyanate and polyol are usually polymerized under the condition that the NCO group is excessive. However, since this polyol has a hydrophilic hydroxyl group, the obtained polyurethane resin composition is obtained. The product has poor moisture resistance. In addition, an isocyanurate-forming catalyst is usually used in the preparation of polyurethane, but this isocyanurate-forming catalyst that remains in the polymer may also act as a decomposition catalyst during actual use at high temperatures. Depending on the isocyanurate-forming catalyst, the desired flame retardancy and heat resistance may not be obtained.

The present invention solves such a problem, and the object of the present invention is to use a polyurethane resin which does not contain atoms such as phosphorus and halogen and has an isocyanurate ring. A flame-retardant polyurethane resin composition having high moisture resistance.

[0006]

The flame-retardant polyurethane resin composition of the present invention has an average oxygen atom content of 20% by weight.
A polyol consisting of one or more of the following components,
NCO / O calculated from the ratio of the number of isocyanate groups and the number of hydroxyl groups of the polyol to the polyol
The polyisocyanate in a weight such that the H index is in the range of 200 or more and 2,000 or less is prepared by
It is characterized by containing polyurethane obtained by reacting with a metal-based isocyanurate-forming catalyst in a ratio of 0.5 parts by weight or more and 20 parts by weight or less with respect to 00 parts by weight. Here, the NCO / OH index refers to a value obtained by multiplying the value obtained by dividing the number of isocyanate groups in polyisocyanate by the number of hydroxyl groups in polyol by 100, and thus the NCO / OH index. = 100 indicates that the number of isocyanate groups and the number of hydroxyl groups are 1: 1.

In the flame-retardant polyurethane resin composition of the present invention, a polyol composed of one or more components having an average oxygen atom content of 20% by weight or less is used. The hydrophilicity of the product is reduced and the moisture resistance is improved.

The flame-retardant polyurethane resin composition of the present invention has an NCO / OH index of 200 or more 2.
It is in the range of 000 or less, and therefore the number of isocyanate groups is present in excess of the number of hydroxyl groups, so that isocyanurate rings are sufficiently formed. The presence of this isocyanurate ring improves the flame retardancy and heat resistance of the resulting polyurethane resin composition.

Furthermore, since the flame-retardant polyurethane resin composition of the present invention is prepared by using a metal-based isocyanurate-forming catalyst, it can be treated at a high temperature as in the case of using an amine-based isocyanurate-forming catalyst. No decomposition of the polyurethane occurs during use.

The flame-retardant polyurethane resin composition of the present invention has the above-mentioned constitution and has a relative humidity of 95 at 120 ° C. with respect to the initial hardness of the flame-retardant polyurethane resin composition.
%, The rate of change in hardness after standing for 100 hours in an atmosphere of 10% or less, and the volume resistivity of 10 ¹¹ Ω · cm or more. High humidity resistance can be secured by setting the rate of change in hardness and the volume resistivity under such conditions as described above.

Further, the flame-retardant polyurethane resin composition of the present invention has the above-mentioned constitution, and is left for 100 hours in an atmosphere of 150 ° C. with respect to the initial hardness of the flame-retardant polyurethane resin composition. The hardness change rate is 10% or less, and the volume resistivity is 10 ¹¹ Ω · cm or more. By setting the rate of change in hardness and the volume resistivity under these conditions as described above, high flame retardancy and heat resistance can be ensured.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. The flame-retardant polyurethane resin composition of the present invention is prepared using a polyol composed of one or more components having an average oxygen atom content of 20% by weight or less. When the average content of this oxygen atom is more than 20% by weight, the obtained flame-retardant polyurethane resin becomes hydrophilic,
It is not preferable because the moisture resistance is reduced.

Examples of preferable polyols include ester reaction products of long-chain fatty acids having a hydroxyl group and polyfunctional polyols. Examples of the long-chain hydroxy fatty acid include ricinoleic acid, oxycaproic acid, oxycapric acid, oxyundecanoic acid, oxylinoleic acid, oxystearic acid, and oxyhexadecenoic acid. Of these, ricinoleic acid and oxystearic acid are It is preferably used. Further, as the polyfunctional polyol, ethylene glycol, propylene glycol, butylene glycol, hexamethylene glycol, difunctional glycol such as diethylene glycol, dipropylene glycol, trifunctional compound such as trimethylolpropane, triethanolamine, diglycerin,
Examples thereof include tetrafunctional compounds such as pentaerythritol, 6 functional compounds such as sorbitol, 8 functional compounds such as sugar, and mixtures thereof.

Examples of the polyisocyanate used in the urethane reaction together with the above polyol include, for example, diphenylmethane diisocyanate (MDI), polymethylene polyphenylene polyisocyanate (crude MDI), polytolylene polyisocyanate (crude TDI) and tolylene diisocyanate (TDI). , Xylylene diisocyanate (XDI), naphthalene diisocyanate (NDI)
Aromatic polyisocyanates such as, hexamethylene diisocyanate (HDI) and other aliphatic polyisocyanates,
Examples thereof include alicyclic polyisocyanates such as isophorone diisocyanate (IPDI), carbodiimide-modified polyisocyanates of the above polyisocyanates, and isocyanurate-modified polyisocyanates.
Further, a reaction product obtained by reacting an excess polyisocyanate with a polyol, which is a so-called urethane prepolymer having an isocyanate group at the molecular end, can be applied, and a mixture thereof can also be used.

In the present invention, the above polyisocyanate is
The amount of polyisocyanate used is determined so that the NCO / OH index is in the range of 200 or more and 2,000 or less. If this NCO / OH index is less than 200, fewer isocyanurate rings will be formed,
It is not preferable because it has poor flame retardancy and heat resistance. Also, NC
When the O / OH index is larger than 2,000, the number of isocyanurate rings substantially formed reaches the upper limit, and the effect of increasing the number of NCO groups cannot be obtained.

In the present invention, the reaction between the above-mentioned polyol and polyisocyanate is carried out using a metal-based isocyanurate-forming catalyst. The metal-based isocyanurate-forming catalyst is used in the range of 0.5 parts by weight or more and 20 parts by weight or less with respect to 100 parts by weight of the polyol. When the amount of the metal-based isocyanurate-forming catalyst is less than 0.5 part by weight, sufficient isocyanurate formation does not occur, which is not preferable. Further, even if the amount of the metal-based isocyanurate-forming catalyst is more than 20 parts by weight with respect to 100 parts by weight of the polyol, the effect corresponding to the added amount cannot be obtained.

As the metal-based isocyanurate-forming catalyst,
For example, a fatty acid metal salt may be mentioned, and specifically, potassium ricinoleate, sodium ricinoleate,
Mention may be made of potassium stearate, sodium stearate, potassium oleate, sodium oleate, potassium acetate, sodium acetate, potassium naphthenate, sodium naphthenate, potassium octylate, sodium octylate, and mixtures thereof.

The flame-retardant polyurethane resin composition of the present invention has a rate of change of hardness of 10% or less with respect to an initial value when left in an atmosphere of 120 ° C. and a relative humidity of 95% for 100 hours, and has a specific volume resistivity. Is 10 ¹¹ Ω · cm or more. Moisture resistance is maintained by such setting values, and
It is sufficiently durable to be used as a sealant, a circuit board storage case, a circuit board material, and the like.

Further, the flame-retardant polyurethane resin composition of the present invention has a rate of change of hardness of 10% or less with respect to an initial value when left in an atmosphere of 150 ° C. for 100 hours, and a volume resistivity of 10 ¹¹ Ω · cm or more. With such set values, flame retardancy and heat resistance are maintained, and it becomes sufficiently durable to be used as an LSI sealant, a circuit board housing case, a circuit board material, and the like.

[0020]

EXAMPLES Hereinafter, the flame-retardant polyurethane resin composition of the present invention will be described in more detail with reference to examples.

Examples 1 to 6 In a 1,000 cc resin cup, 100 g of the polyol shown in Table 1, 1 g of the metal-based isocyanurate-forming catalyst, and a predetermined amount of the polyisocyanate shown in Table 1 were mixed, After deaeration, it was poured into an aluminum mold at 25 ° C. and cured in about 3 minutes. This cured product was cut into a 40 mm square to prepare a test piece. Using this test piece, the following heat resistance test, room temperature test, moisture resistance test and flame retardancy test were conducted. The results are also shown in Table 1.

Comparative Examples 1 to 4 Comparative Examples 1 to 4 were carried out with the compositions shown in Comparative Examples 1 to 4 of Table 1 in the same manner as in Examples 1 to 6.
~ 4 flame-retardant polyurethane resins were obtained, and using the same, test pieces were prepared in the same manner as in Examples 1-6. Using this test piece, the following heat resistance test, room temperature test, moisture resistance test and flame retardancy test were conducted. The results are also shown in Table 1.

[0023]

[Table 1]

(Flame Retardancy Test) US Flame Retardancy Test Method UL-9
A flame retardancy test was performed according to 4 (1/8 inch). Table 1
The evaluation criteria of "◎", "○", and "x" in the column of the flame retardancy test of are as follows.

[0025] ◎ ... V-0 ○ ... V-2 × ... HB.

(Heat Resistance Test) First, the initial hardness of the test piece was measured. Next, after leaving this test piece in an atmosphere of 150 ° C. for 100 hours, its hardness was measured. And
The rate of change of the hardness with respect to the initial hardness was obtained. The volume resistivity of the same test piece was measured. The evaluation criteria for “◯”, “Δ” and “x” in the heat resistance test column of Table 1 are as follows.

O: Hardness change is 10% or less, volume specific resistance is 10 ¹¹ Ω · cm or more Δ: Hardness change is 10% or less, volume specific resistance is 10 ¹¹ Ω
・ Small less than cm × ... Change in hardness is greater than 10%, volume resistivity is 10 ¹¹
Smaller than Ω · cm.

(Moisture resistance test) First, the initial hardness of the test piece was measured. Next, this test piece was heated at 120 ° C. and a relative humidity of 9
After being left in a 5% atmosphere for 100 hours, its hardness was measured. Then, the rate of change of the hardness with respect to the initial hardness was obtained. The volume resistivity of the same test piece was measured. The evaluation criteria of “◯”, “Δ” and “x” in the column of the moisture resistance test in Table 1 are as follows.

◯: Hardness change is 10% or less, volume specific resistance is 10 ¹¹ Ω · cm or more Δ: Hardness change is 10% or less, volume specific resistance is 10 ¹¹ Ω
・ Small less than cm × ... Change in hardness is greater than 10%, volume resistivity is 10 ¹¹
Smaller than Ω · cm.

(Room Temperature Curing Test) What was cured within 5 minutes after mixing the polyol, polyisocyanate and the metal-based isocyanurate-forming catalyst was marked with "○", and not cured even after 5 minutes. The thing was designated as "x".

(Test Results) From the results of the tests shown in Table 1, the flame-retardant polyurethane resins of Examples 1 to 6 were all evaluated as “◯” in any test, and the flame retardancy and heat resistance It was proved that it was excellent in resistance and moisture resistance. On the other hand, the flame-retardant polyurethane resins of Comparative Examples 1 to 4 were evaluated as Δ or × in any test, and particularly in the moisture resistance test, satisfactory results were obtained in all comparative examples. I couldn't get it.

(Examples 7 to 12) Next, the influence of the difference in the type and amount of isocyanurate-forming catalyst on polyisocyanate was examined. The composition shown in Table 2 is used in Examples 1 to
By the same operation as in 6, the flame-retardant polyurethane resins of Examples 7 to 12 were obtained and each test piece was prepared. The same tests as in Table 1 were performed on the test pieces of Examples 7 to 12, and the results are also shown in Table 2.

(Comparative Examples 5-9) Next, with the composition shown in Table 2, the flame-retardant polyurethane resins of Comparative Examples 5-9 were obtained by the same operation as in Examples 1-6, and each test piece was prepared. did. The same tests as in Table 1 were performed on the test pieces of Comparative Examples 5 to 9, and the results are also shown in Table 2.

[0034]

[Table 2]

(Test Results) From the results of each test in Table 2, the flame-retardant polyurethane resins of Examples 7 to 9 using potassium ricinoleate, which is a metal-based isocyanurate-forming catalyst, were
In all of the tests, the evaluation was "O", and it was found that the flame retardancy, heat resistance and moisture resistance were excellent. On the other hand, the flame-retardant polyurethane resins of Comparative Examples 5 to 9 were evaluated as Δ or × in any test, and particularly in the heat resistance test and the moisture resistance test, in all the comparative examples. I could not get a satisfactory result. Further, Comparative Example 6 is a case where the metal-based isocyanurate-forming catalyst and the amine-based isocyanurate-forming catalyst are used in combination, but the metal-based isocyanurate-forming catalyst is 0.5 parts by weight or more and 20 parts by weight or more per 100 parts by weight of the polyol. It can be seen that the flame retardancy, the heat resistance and the moisture resistance are reduced in the presence of the amine-based isocyanurate-forming catalyst even when used in a ratio of not more than 1 part.

In addition, the flame-retardant polyurethane resin compositions of all the above examples are cured within 5 minutes after mixing the polyol, polyisocyanate, and metal-based isocyanurate-forming catalyst, so that no curing furnace is required. Therefore, there is an advantage that productivity is increased and cost can be reduced.

[0037]

The flame-retardant polyurethane resin composition of the present invention has a high content since it is prepared by using a polyol composed of one or more components having an average oxygen atom content of 20% by weight or less. Has moisture resistance. Also, NCO / OH
Since it is obtained by reacting a polyol and a polyisocyanate having an index in the range of 200 or more and 2,000 or less, the isocyanurate ring is sufficiently formed, and the obtained polyurethane resin composition has high flame retardancy and heat resistance. is doing. Furthermore, the flame-retardant polyurethane resin composition of the present invention has an amount of 0.
Since it is obtained by reacting with a metal-based isocyanurate-forming catalyst in a ratio of 5 parts by weight or more and 20 parts by weight or less, decomposition of polyurethane does not occur even when used at high temperature.

The flame-retardant polyurethane resin composition of the present invention is 100% in an atmosphere of 120 ° C. and 95% relative humidity.
The rate of change in hardness when left for 10 hours or less,
Since the volume resistivity is 10 ¹¹ Ω · cm or more, high moisture resistance can be secured.

The flame-retardant polyurethane resin composition of the present invention has a rate of change in hardness of 10% or less when left in an atmosphere of 150 ° C. for 100 hours, and a volume resistivity of 10 ¹¹ Ω · cm. Because of the above, high flame retardancy and heat resistance can be secured.

Claims (3)

(57) [Claims] 1. A mixture of ricinoleic acid and a polyfunctional polyol.
Consists of stell reaction products and has an average oxygen content of 2
0% by weight or less of a polyol composed of one or more components, and NCO / O calculated from the ratio of the number of isocyanate groups and the number of hydroxyl groups of the polyol with respect to the polyol.
A polyisocyanate having a weight ratio of H to 200 or more and 2,000 or less is used, and a metal-based isocyanurate-forming catalyst is used in a ratio of 0.5 to 20 parts by weight with respect to 100 parts by weight of the polyol. A flame-retardant polyurethane resin composition, characterized by containing a polyurethane obtained by reacting the same. 2. The polyfunctional polyol is ethylene glycol.
Cole, propylene glycol, butylene glycol,
Hexamethylene glycol, diethylene glycol, di
Propylene glycol, trimethylolpropane, tri
Ethanolamine, diglycerin, pentaerythritol
Tomato, sorbitol, octafunctional sugar and mixtures thereof
The flame-retardant polymer according to claim 1, which is selected from
Retan resin composition. 3. The polyisocyanate is diphenyl
Methane diisocyanate, polymethylene polyphenylene
Polyisocyanate, polytolylene polyisocyanate
Tolylene diisocyanate, xylylene diisocyanate
Nate, naphthalene diisocyanate, hexamethylene
Diisocyanate, isophorone diisocyanate, this
Carbodiimide-modified polyiso of these polyisocyanates
Cyanate and isocyanurate modified polyisocyanate
And urethane having an isocyanate group at the molecular end
Selected from prepolymers and mixtures thereof
A flame-retardant polyurethane resin according to claim 1 or 2.
Fat composition.