JPH0873554A - Polyol composition for rigid polyurethane foam and its use - Google Patents

Abstract

PURPOSE: To obtain a polyol composition which can give a rigid fine-cell polyurethane foam excellent in thermal conductivity and foam flowability when the foaming is performed by using a hydrocarbon blowing agent having no risk of depleting the ozonosphere by using specified polyol components. CONSTITUTION: This composition contains a mixture of a polyol mixture comprising a polyether polyol obtained by the addition reaction of sucrose with propylene oxide(PO), a polyether polyl obtained by the addition reaction of propylene glycol with PO and a polyamine polyol obtained by the addition reaction of a polyamine with ethylene oxide(EO) and/or PO with an additive which is at least one member selected from between formic acid and an emulsifier of a hydroxyl value of 20-120mgKOH/g obtained by the addition reaction of propylene glycol and/or glycerol with EO and/or PO.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to polyol compositions for use in making rigid polyurethane foams using water and hydrocarbons as blowing agents and their uses.

[0002]

2. Description of the Related Art Conventionally, a rigid polyurethane foam has used a chlorofluorocarbon type foaming agent such as CFC-11, which has excellent thermal conductivity, as a foaming agent. However, this chlorofluorocarbon-based foaming agent has been pointed out as a substance that may destroy the ozone layer in the atmosphere, and has become difficult to use. Against this background, there is a need for rigid polyurethane foams made with hydrocarbons that are not chlorofluorocarbons as blowing agents.

[0003]

So far, rigid polyurethane foams produced using hydrocarbon as a blowing agent have remarkably coarse cells and thermal conductivity as compared with rigid polyurethane foams using a low boiling point chlorofluorocarbon type blowing agent. And the fluidity of the foam tended to deteriorate.

[0004]

An object of the present invention is to produce a rigid polyurethane foam without the above-mentioned problems. The present invention comprises a1) a polyether polyol obtained by adding propylene oxide to sucrose, a2) a polyether polyol obtained by adding propylene oxide to propylene glycol, and a3) ethylene oxide and / or propylene oxide to a polyamine. A polyol mixture a) comprising a polyamine polyol obtained by addition, b1) formic acid, and b2) a hydroxyl value of 20 to 120 mg KOH / obtained by adding ethylene oxide and / or propylene oxide to propylene glycol and / or glycerin.
at least one additive b) selected from g.
And a polyol composition for rigid polyurethane foam comprising a mixture of Further, the present invention is a curable composition for a rigid polyurethane foam, which comprises a polyol component, a polyisocyanate component, a catalyst, a foam stabilizer, and a foaming agent, wherein the foaming agent is water and hydrocarbon, The polyol component is a1) a polyether polyol obtained by adding propylene oxide to sucrose, a2) a polyether polyol obtained by adding propylene oxide to propylene glycol, and a3) ethylene oxide and / or propylene oxide to a polyamine. A polyol mixture a) comprising a polyamine polyol obtained by addition, b1) formic acid, and b2) a hydroxyl value 20 obtained by adding ethylene oxide and / or propylene oxide to propylene glycol and / or glycerin. 120mgKOH /
at least one additive b) selected from g.
It relates to a curable composition for rigid polyurethane foam which is a mixture with. In addition, the present invention is a method for producing a rigid polyurethane foam obtained by reacting a polyol component and a polyisocyanate component in the presence of a catalyst, a foam stabilizer, and a foaming agent, while using water and hydrocarbon as the foaming agent. As the polyol component, a1) sucrose and propylene oxide (hereinafter,
It is called PO. A) a polyether polyol obtained by adding PO to a propylene glycol, and a3) a polyether polyol obtained by adding ethylene oxide (hereinafter referred to as EO) and / or PO to a polyamine. A) a polyol mixture consisting of a polyamine polyol, and b1) formic acid, and b2) at least an emulsifier having a hydroxyl value of 20 to 120 mgKOH / g obtained by adding EO and / or PO to propylene glycol and / or glycerin. It relates to a process for producing rigid polyurethane foams which comprises using a mixture with one additive b). Furthermore, the present invention also relates to a rigid polyurethane foam obtained by curing the curable composition.

In the present invention, the polyol component comprises a polyol mixture a) and an additive b). The polyol mixture a) includes a1) a polyether polyol obtained by adding PO to sucrose, a2) a polyether polyol obtained by adding PO to propylene glycol, and a3) EO and / or PO added to a polyamine. It consists of a polyamine polyol obtained by

The polyether polyol a1) is obtained by adding PO to sucrose. The hydroxyl value of the polyether polyol a1) is usually 250 to 550 mgK.
OH / g, preferably 350-500 mg KOH / g. The amount of polyether polyol a1) is usually 10-90 parts by weight, preferably 40-70 parts by weight, per 100 parts by weight of polyol mixture a).

The polyether polyol a2) is obtained by adding PO to propylene glycol. The hydroxyl value of the polyether polyol a2) is usually 150 to 650.
mgKOH / g, preferably 200-600 mgKOH
/ G. The amount of polyether polyol a2) is usually 5-40 per 100 parts by weight of polyol mixture a).
Parts by weight, preferably 10 to 20 parts by weight.

The polyamine polyol a3) can be obtained by adding EO and / or PO to a polyamine (divalent or higher valent amine). The polyamine may be an aromatic polyamine, an aliphatic polyamine and the like. The polyamine is preferably a diamine. Examples of polyamines are tolylenediamine, ethylenediamine, triethanolamine. The hydroxyl value of the polyamine polyol a3) is usually 200 to 850 mgKOH / g, preferably 350 to 800 mgKOH / g. The amount of polyamine polyol a3) is based on the polyol mixture a) 100.
It is usually 5 to 90 parts by weight, preferably 10 to 50 parts by weight per part by weight.

The average hydroxyl value of the polyether mixture a) is usually 250 to 650 mgKOH / g, preferably 3
It is 00-600 mgKOH / g.

The additive b) is at least one selected from b1) formic acid, and b2) an emulsifier having a hydroxyl value of 20 to 120 mgKOH / g obtained by adding EO and / or PO to propylene glycol and / or glycerin. Is a compound of. The hydroxyl value of the emulsifier b2) is 20 to 120 mgKOH / g, preferably 25 to 1
It is 00 mgKOH / g. The amount of additive b) is usually 0.5 to 20 per 100 parts by weight of polyol mixture a).
Parts by weight, preferably 1 to 10 parts by weight.

As the polyisocyanate component, aromatic polyisocyanate, aliphatic polyisocyanate, alicyclic polyisocyanate and modified products thereof such as diphenylmethane diisocyanate, polymethylene polyphenyl isocyanate, tolylene diisocyanate, crude tolylene diisocyanate, xylyl are used. Diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate, modified (carbodiimide modified etc.) diphenylmethane diisocyanate, etc., or by reacting an excess amount of these polyisocyanates with a polyol (for example, a low molecular weight polyol or polymer polyol) N at the end obtained
Urethane prepolymer having a CO group (for example, NCO
Content rate: 5 to 35%) and the like. These polyisocyanates can be used alone or in combination of two or more. The polyisocyanate component is preferably composed of at least one of diphenylmethane diisocyanate, polymethylene polyphenyl isocyanate, tolylene diisocyanate and modified products thereof. The use ratio of the polyisocyanate component and the polyol component is such that the equivalent ratio of the NCO group of the polyisocyanate component and the OH group of the polyol component is NCO group: OH group = 1.
A range of up to 1.5: 1 is preferred.

As the catalyst, for example, triethylamine,
Tripropylamine, triisopropanolamine, tributylamine, trioctylamine, hexadecyldimethylamine, N-methylmorpholine, N-ethylmorpholine, N-octadecylmorpholine, N, N, N ', N'.
-Tetramethylethylenediamine, N, N, N ', N'-tetramethylpropylenediamine, N, N, N', N'-tetramethylbutanediamine, N, N, N ', N'-tetramethyl-1, 3-butanediamine, N, N, N ', N'-tetramethylhexamethylenediamine, bis [2- (N, N-dimethylamino) ethyl] ether, N, N-dimethylcyclohexylamine, N, N, N ', N ", N" -Pentamethyldiethylenetriamine, triethylenediamine, organic acid salts of triethylenediamine, alkylene oxide adducts of amino groups of primary amines and secondary amines, and N, N-dialkylpiperazines Examples thereof include cyclic compounds and organometallic catalysts. The amount of the catalyst added is usually 0.01 to 10 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the polyol component.

Blowing agents are water and hydrocarbons. The hydrocarbon may have an oxygen atom but does not contain a halogen atom. Examples of hydrocarbons are propane, butane, pentane, isopentane, cyclopentane, cyclohexane, dimethyl ether, diethyl ether. The blending ratio of the foaming agent is 100 parts by weight of the polyol component,
Water is usually 0.5 to 10 parts by weight, preferably 1 to 3 parts by weight, and hydrocarbon is usually 1 to 40 parts by weight, preferably 2 to 20 parts by weight. If the amount of water is less than 0.5 parts by weight, the foam density will be high, and if it exceeds 10 parts by weight, the cells will become coarser and foam shrinkage will tend to occur.
If the amount of hydrocarbons is less than 1 part by weight, the cells will be non-uniform and the foam density will be high, and if it exceeds 40 parts by weight, the cells will be coarse and the cells will tend to be non-uniform.

The foam stabilizer may be, for example, any of nonionic, cationic and anionic surfactants, with organic silicone surfactants being preferred. The amount of the foam stabilizer added is usually 0.1 to 100 parts by weight of the polyol.
It is 10 parts by weight, preferably 0.1 to 3 parts by weight. In the present invention, various additives that have been conventionally added to rigid polyurethane foams such as flame retardants, carbon black, and colorants can be added. The amount of flame retardant added is preferably 0 to 30 parts by weight per 100 parts by weight of the polyol component.

To obtain a rigid polyurethane foam, for example, a polyurethane foaming machine is used, and a polyol component, a catalyst, a foam stabilizer, a foaming agent, a flame retardant, a polyisocyanate component, etc. are continuously or discontinuously mixed in a fixed ratio. do it. In the rigid polyurethane foam, the cell size is usually 50 to 400 μm. The rigid polyurethane foam of the present invention can be used as a heat insulating material and a structural material.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below with reference to Examples and Comparative Examples.

Examples 1 to 7 and Comparative Examples 1 to 6 Using a high-pressure foaming machine equipped with a mixing head, the polyol mixture, the additive, the foam stabilizer, the foaming agent and the catalyst shown in Tables 1 and 2 were mixed by stirring. Then, the polyisocyanate component was added thereto and mixed with stirring. Immediately after mixing, the mixture was poured into a mold and allowed to freely foam to obtain a rigid polyurethane foam.
The physical properties of the obtained foam are shown in Tables 1 and 2. The polyol mixture used, additives (formic acid or emulsifier),
The catalyst, foam stabilizer and polyisocyanate component are as follows.

Polyol mixture: 1) Hydroxyl number 400 mg KOH / obtained by adding PO to sucrose
g of polyether polyol, 2) hydroxyl value 500 mg KOH obtained by adding PO to propylene glycol
/ G of polyether polyol, and 3) hydroxyl value of 4 obtained by adding EO and PO to tolylenediamine
A mixture of 10 mg KOH / g of polyamine polyol and an average hydroxyl value of 415 mg KOH / g. Emulsifier (1): Polyether polyol having a hydroxyl value of 56 mgKOH / g, which is PO added to propylene glycol Emulsifier (2): Polyether polyol having a hydroxyl value of 28 mgKOH / g, which is obtained by adding EO and PO to glycerin Foam stabilizer: Nippon Unicar L5420 catalyst: POLYCAT 8 polyisocyanate (A) manufactured by San-Apro Co .: polymethylene polyphenyl isocyanate + tolylene diisocyanate modified product,
NCO content 31.1% Polyisocyanate (B): Polymethylene polyphenyl isocyanate + diphenylmethane diisocyanate modified product, NCO content 30.9% Polyisocyanate (C): Polymethylene polyphenyl isocyanate + polymethylene polyphenyl isocyanate modified product , NCO content 30.3% Polyisocyanate (D): Polymethylene polyphenyl isocyanate, NCO content 31.5%

The physical properties of the foam were examined as follows. Free blow density: Inner dimension 150 mm x 300 mm x
Foam density when free-foaming in a 150 mm veneer box. Thermal conductivity: 200 mm x 200 m obtained by free foaming
Anac made by Anacon mx 25 mm (thickness) foam
Measured using CON model 88 at an average temperature of 23.7 ° C. Foam fluidity: Foam reach when foaming is performed at a mold temperature of 40 ° C. in a cylindrical mold having a diameter of 100 mm.

[0020]

Table 1 Example Example Example Example Example Comparative Example Comparative Example Comparative Example Comparative Example 1 2 3 4 1 2 3 4 Polyol Mixture 100 100 100 100 100 100 100 100 Formic Acid 0.5 0.5 0.5 0.5 --- Catalyst 2.8 2.8 2.6 2.6 2.8 2.6 2.8 2.6 Foam stabilizer 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 Water 2.0 2.0 2.0 2.0 2.0 2.0 2.0 2.0 Cyclopentane 9 9 9 9 10 10 10 10 Polyisocyanate (A) − − − 132 − − − 132 ( B) − − 132 − − 132 − − (C) − 135 − − − − 135 − (D) 131 − − − 130 − − − Reactive cream time (sec) 11 10 10 9 10 10 10 10 Gel time (sec) ) 51 49 50 49 49 48 49 50 Physical properties Free blow density 27.5 27.9 28.2 28.4 27.8 28.4 27.9 28.1 (kg / m ³ ) Thermal conductivity 152 153 152 152 169 168 168 168 (× 10 ^-4 kcal / m ・ hr ・ ° C) ) Foam fluidity 73.5 73.8 73.1 72.9 70.1 69.7 70.0 70.2 (cm) Average cell diameter (μm) 150 100 100 100 400 400 400 300 Note) Composition unit is parts by weight

[0021]

Table 2 Example 5 Example 6 Comparative Example 5 Comparative Example 6 Polyol Mixture 100 100 100 100 100 Emulsifier (1) -3-- Emulsifier (2) 3-- Foam stabilizer 2.0 2.0 2.0 2.0 Catalyst 2.8 2.8 2.8 2.6 Water 2.0 2.0 2.0 2.0 Cyclopentane 10 10 10 10 Polyisocyanate (D) 126 127 127 129 130 Reactive Cream Time (sec) ) 10 10 10 10 Gel time (sec) 50 50 50 49 50 Physical property-free Blow density (kg / m ³ ) 27.9 28.0 27.8 28.1 Thermal conductivity 162 160 169 168 (× 10 ^-4 kcal / m)・ Hr ・ ° C) Foam fluidity (cm) 72.8 73.3 70.1 70.2 Average cell diameter (μm) 220 200 400 430 Note) Composition unit is parts by weight

[0022]

The gas generated by the reaction between the formic acid and the isocyanate component added to the polyol mixture serves as the nucleus when the cells are formed during foaming, so that it is a fine cell hard material having excellent thermal conductivity and foam fluidity. A polyurethane foam is obtained. Since the gas is generated by the reaction between the formic acid and the isocyanate component, it is possible to reduce the water content. Addition of an emulsifier makes it possible to control the solubility of the hydrocarbon-based blowing agent in the polyol component. As a result, the foaming agent can be efficiently vaporized at the time of foaming, and the rigid polyurethane foam having excellent foam fluidity and low thermal conductivity can be obtained. According to the present invention, a fine cell rigid polyurethane foam excellent in thermal conductivity and foam fluidity can be obtained by using a hydrocarbon-based foaming agent that does not damage the ozone layer.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor, Koji Nakatani, 3-13-26, Kuguchi, Amagasaki City, Hyogo Prefecture Sumitomo Bayer Urethane Co., Ltd. (72) Inventor, Toshikazu Mukai, 3-13-26, Kuguchi, Amagasaki City Sumitomo Bayer Urethane Co., Ltd.

Claims (4)

[Claims] 1. A1) a polyether polyol obtained by adding propylene oxide to sucrose, a2) a polyether polyol obtained by adding propylene oxide to propylene glycol, and a3) ethylene oxide and / or propylene oxide to a polyamine. A) a polyol mixture consisting of a polyamine polyol obtained by adding a), b1) formic acid, and b2) a hydroxyl value obtained by adding ethylene oxide and / or propylene oxide to propylene glycol and / or glycerin, 20 to 120 mgKOH /
at least one additive b) selected from g.
A polyol composition for rigid polyurethane foam, which comprises a mixture with 2. A curable composition for a rigid polyurethane foam, comprising a polyol component, a polyisocyanate component, a catalyst, a foam stabilizer, and a foaming agent, wherein the foaming agent is water and a hydrocarbon. The components are a1) a polyether polyol obtained by adding propylene oxide to sucrose, a2) a polyether polyol obtained by adding propylene oxide to propylene glycol, and a3) addition of ethylene oxide and / or propylene oxide to a polyamine. And a hydroxyl mixture having a hydroxyl value of 20 to 20 which is obtained by adding ethylene oxide and / or propylene oxide to b1) formic acid, and b2) propylene glycol and / or glycerin. 20mgKOH /
at least one additive b) selected from g.
A curable composition for rigid polyurethane foam, which is a mixture with. 3. A method for producing a rigid polyurethane foam, which comprises reacting a polyol component and a polyisocyanate component in the presence of a catalyst, a foam stabilizer and a foaming agent, wherein water and a hydrocarbon are used as the foaming agent, and As a polyol component, a1) a polyether polyol obtained by adding propylene oxide to sucrose, a2) a polyether polyol obtained by adding propylene oxide to propylene glycol, and a3) ethylene oxide and / or propylene oxide to a polyamine. A polyol mixture a) comprising a polyamine polyol obtained by addition, b1) formic acid, and b2) propylene glycol and / or glycerin with ethylene oxide and / or propylene oxide Obtained Te hydroxyl value 20~120mgKOH /
at least one additive b) selected from g.
A method for producing a rigid polyurethane foam, which comprises using a mixture with 4. A rigid polyurethane foam obtained by curing the curable composition according to claim 2.