JP3319695B2 - Polyurethane diel-like composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyurethane gel composition useful as a sealing material for use in a clean room and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, a silicon-based air seal material has been used as an air seal material in a clean room. However, as the demand for cleanliness in a clean room increases, siloxane, which is a decomposition product, has become a problem as a pollutant. .

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an air seal material which does not generate contaminants such as siloxane which lowers the cleanliness in a clean room. In order to do so, it is required that the raw material has characteristics such as low vapor pressure, high boiling point, difficulty in decomposing, and no gas generation even when decomposed. It is a condition that no component that generates is included. Further, it is required to have properties such as gas barrier properties, adhesive properties, appropriate hardness, and flame retardancy. As a result of diligent research for a material satisfying these requirements, the following results were obtained.
Is reacted in at least one ester compound selected from phthalic esters, trimellitic esters and pyromellitic esters having a molecular weight in the range of 390 to 710, and has an average molecular weight of 35.
15 to 50% by weight of a polybutadiene urethane prepolymer having an OH group at a terminal within a range of from 00 to 7000
(B) a purified MDI obtained by dissolving the purified MDI in at least one ester compound selected from phthalic esters, trimellitic esters and pyromellitic esters having a molecular weight of 390 to 710; From 1.2 to 1.8
(C) a polyurethane gel-like composition obtained by mixing and reacting with the ester compound solution in the presence of a catalyst for accelerating the urethane reaction. It has been found that the above other required properties of the material are also satisfied.

Thus, the present invention provides the above-mentioned polyurethane gel composition.

The solution (A) used in the production of the composition of the present invention comprises a polybutadiene urethane prepolymer obtained by reacting a polybutadiene having an OH group at a terminal with purified MDI in an ester compound as a solvent. It is an ester compound solution containing at a concentration of 15 to 50% by weight, preferably 20 to 40% by weight. The polybutadiene having an OH group at the terminal used for preparing the prepolymer has a number average molecular weight of 1,000 to 3,000,
Preferably, those in the range of 1200 to 2800 are used. Such OH-terminated polybutadienes are known per se and are described, for example, in the Journal of Polymer Sci.
ence: Polymer Chemistry Edition ,. Vol. 21, 38
5-395 (1983).

[0006] The ester compound used as a solvent is selected from phthalic acid esters, trimellitic acid esters and pyromellitic acid esters having a molecular weight in the range of 390 to 710. Di-n-octyl, di-i-octyl phthalate, di-2-ethylhexyl phthalate, di-2-ethylhexyl phthalate, di-n-nonyl phthalate, di-i-nonyl phthalate, di-nonyl phthalate di-C _8-13 alkyl phthalates such as n-decyl, di-i-decyl phthalate, ditridecyl phthalate; tri-n-octyl trimellitate, tri-2-ethylhexyl trimellitate, tri-trimellitate
tri-C _8-10 alkyl trimellitate such as i-nonyl and tri-i-decyl trimellitate; tetra-C pyromellitic acid such as tetra-n-octyl pyromellitic acid and tetra-2-ethylhexyl pyromellitic acid _8- alkyl and the like. Each of these ester compounds can be used alone, or two or more thereof can be used in combination.

The reaction between OH-terminated polybutadiene and purified MDI in such an ester compound can be usually carried out at a temperature of about 20 to about 80 ° C. in an inert atmosphere. Fine MD for OH-terminated polybutadiene at that time
The proportion of I used can generally be in the range of 1 / 0.01 to 1 / 0.25 by weight of OH-terminated polybutadiene / purified MDI.

[0008] The polybutadiene urethane prepolymer obtained by this reaction can have a number average molecular weight in the range of 3500-7000, preferably 4000-6000.

On the other hand, the solution (B) to be reacted with the solution (A) according to the present invention is a solution of purified MDI dissolved in the ester compound as described above.
To 1.8% by weight, preferably 1.3 to 1.6% by weight.

The reaction between the polybutadiene urethane prepolymer in the solution (A) and the purified MDI in the solution (B) can be carried out in the presence of a catalyst that promotes the urethane reaction. The urethanization catalyst used includes, for example, tertiary amines and organotin compounds usually used for urethane reaction, and more specifically, tertiary amines such as triethylenediamine, bis (dimethylaminoethyl) ether, Tris (dimethylaminopropyl) -hexahydro-S-triazine, 1,8-diazabicyclo- [5.4.0] undecene-7 salt, 1-isobutyl-2-methylimidazole, trimethylaminoethylpiperazine, etc .; organotin compounds Dibutyltin dilaurate, dibutyltin bisbutylmalate, dibutyltin bislauryl Kapuchido, dibutyltin bis isooctyl maleate, etc. dibutyltin bis isooctyl mercaptoacetate and the like.

In the above reaction, the solution (A) and the solution (B) are mixed, and the polybutadiene urethane prepolymer is brought into contact with purified MDI at a temperature of about 0 to about 80 ° C. in the presence of the catalyst to obtain 0.5. The reaction can be performed for about 24 hours. At this time, the solution (A) and the solution (B) generally have a ratio of the number of moles of OH derived from the polybutadiene urethane prepolymer in the solution (A) to the number of moles of NCO derived from the purified MDI in the solution (B). An isocyanate index represented by NCO / OH of 0.8 to 1.5, preferably 0.8 to 1.5;
It is mixed so as to be within the range of 1.3. At that time, if necessary, a dye is added to the solution (A) and / or the solution (B).
An additive such as a pigment may be added.

The polyurethane diel-like composition of the present invention thus obtained has excellent flame retardancy and does not require the addition of a flame retardant. Phosphorus compounds such as phosphoric acid esters and halogen compounds represented by chlorinated paraffins are usually used as flame retardants for polyurethanes. These compounds often corrode metals, and are intended to be used as air seal materials in clean rooms. It is a great advantage that the use of such corrosion-causing flame retardants in the compositions of the invention can be avoided.

In the composition of the present invention, the viscosity of the mixture before curing is low, and the mixed air bubbles are naturally removed before curing. Therefore, a defoaming agent, for example, a silane-based defoaming agent which causes siloxane generation. There is an advantage that it is not necessary to use a foaming agent.

[0014]

The present invention will be described more specifically with reference to the following examples. The abbreviations used in the examples have the following meanings.

ISONATE 125M Pure MDI (Mitsubishi Chemical Dow) R-15HT Liquid polybutadiene (Idemitsu Petrochemical) R-45HT Liquid polybutadiene (Idemitsu Petrochemical) DBTDL Dibutyltin laurate diester (Katsuda Chemical) T-52NJ Organic Tin compound (manufactured by Air Products) DABCO 120 Organic tin compound (manufactured by Air Products) DABCO 125 Organic tin compound (manufactured by Air Products) DABCO 131 Organic tin compound (manufactured by Air Products) DABCO crystal Triethylenediamine (manufactured by Air Products) DnOP diphthalic acid Normal octyl DiOP Diisooctyl phthalate DOP Di-2-ethylhexyl phthalate DnNP Dinormalonyl phthalate DiNP Diisononyl phthalate DnDP Dinormal decyl phthalate DiDP Diisodecyl phthalate DTDP Ditridecyl phthalate TnOTM Trinormal octyl trimellitate TiOTM Isooctyl TOTM trimellitic acid Tri-2-ethylhexyl TiNTM Triisononyl trimellitate TiDTM Triisodecyl trimellitate TnOPM Tetra normal octyl pyromellitate TOPM Tetra-2-ethylhexyl pyromellitate PP Polybutadiene urethane prepolymer Example 1 Nitrogen stream in a 300 ml flask equipped with a stirrer After 68 g of DnOP and 28.5 g of R-45HT were added and mixed, the temperature was raised to 70 ° C., and 1.5 g of purified MDI was added. After stirring and reacting at 70 ° C. for 24 hours, the temperature was returned to room temperature, 2.0 g of DBTDL was added, and the number average molecular weight was 51%.
30% by weight of a prepolymer having an OH group at the terminal at 00
A liquid component A was obtained at a concentration of

In a 300 ml flask equipped with a stirrer, 98.5 g of DnOP was added, and the temperature was raised to 70 ° C.
I1.5 g was added to obtain a liquid component B having an NCO% of 0.5%.

The liquid component A (50 g) and the liquid component B50
g were mixed in a 300 ml beaker, stirred for 1 minute with a glass rod, and then left at room temperature for 12 hours to obtain a polyurethane gel composition.

Examples 2 to 35 and Comparative Examples 1 to 18 Using the components shown in Table 1 or Table 2, a polyurethane (die) composition was produced in the same manner as in Example 1. The properties of the resulting liquid A, liquid B, and final composition (cured product) are shown in Table 1 or Table 2.

[0019]

[Table 1]

[0020]

[Table 2]

[0021]

[Table 3]

[0022]

[Table 4]

[0023]

[Table 5]

[0024]

[Table 6]

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) C08G 18/00-18/87

Claims (3)

(57) [Claims] (A) an average molecular weight of 1000 to 30
Polybutadiene having an OH group at the terminal and purified diphenylmethane diisocyanate (MDI)
Is reacted in at least one ester compound selected from phthalic esters, trimellitic esters and pyromellitic esters having a molecular weight in the range of 390 to 710, and has an average molecular weight of 35.
15 to 50% by weight of a polybutadiene urethane prepolymer having an OH group at the terminal in a range of from 00 to 7000
(B) purified diphenylmethane diisocyanate (MD
The purified MDI obtained by dissolving I) in at least one ester compound selected from phthalic acid esters, trimellitic acid esters and pyromellitic acid esters having a molecular weight in the range of 390 to 710 is 1.2. ~
(C) A polyurethane gel composition obtained by mixing and reacting the ester compound solution containing 1.8% by weight with (C) a catalyst for promoting a urethane reaction. 2. The method according to claim 1, wherein the ester compound is di-n-octyl phthalate, di-i-octyl phthalate or di-2-phthalic acid.
Ethylhexyl, di-n-nonyl phthalate, di-i-nonyl phthalate, di-n-decyl phthalate, di-phthalate
i-decyl, ditridecyl phthalate, tri-n-octyl trimellitate, tri-2-ethylhexyl trimellitate, tri-i-nonyl trimellitate, tri-i-decyl trimellitate, tetra-n pyromellitic acid The composition according to claim 1, wherein the composition is selected from -octyl and tetra-2-ethylhexyl pyromellitic acid. 3. The solution (A) according to claim 1 and the solution (B) according to claim 1 are combined with the number of moles of OH contained in the solution (A) and the number of moles of NCO contained in the solution (B). Ratio NCO / O
The composition according to claim 1, which is obtained by mixing and reacting so that the isocyanate index represented by H is 0.8 to 1.5.