JP5207303B2 - Polyol composition for rigid polyurethane foam and method for producing rigid polyurethane foam - Google Patents

Description

  The present invention relates to a polyol composition for rigid polyurethane foam having high flame retardancy and a method for producing a rigid polyurethane foam using the polyol composition.

  Rigid polyurethane foam is a well-known material as a heat insulating material, a lightweight structural material, and the like. Such a rigid polyurethane foam is formed by mixing a polyol composition containing a polyol compound and a foaming agent as essential components and a polyisocyanate component, and foaming and curing. Rigid polyurethane foam used as a building material is required to have flame retardancy, and the use of aromatic polyester polyols is advantageous in improving flame retardancy as a method for enhancing flame retardancy by the molecular structure of polyurethane foam. This has been known (Patent Document 1).

  However, when the ratio of the aromatic polyester polyol in the polyurethane constituting the foam is increased, the fluidity of the polyol composition is lowered and the moldability of the foam is lowered, and the formed foam becomes brittle and the physical properties are lowered. Therefore, it is indispensable to use a polyether polyol of at least about 10%, usually about 20%, as employed in the examples of Patent Document 1. Then, as a result of using the polyether polyol, the flame retardancy and heat resistance of the foam are lowered, and the use of a flame retardant is indispensable for improving the flame retardancy. Further, when the ratio of the aromatic polyester polyol in the polyurethane constituting the foam is increased, the compatibility of the HFC compound in the polyol composition is low when the HFC compound having a small ozone layer destructive coefficient is used as the blowing agent component. Therefore, the problem that the uniformity of the cell (bubble) which comprises a foam falls arises. In order to prevent such a problem, it was indispensable to use a polyether polyol having good compatibility with the HFC compound.

  In addition, as a technique for improving the heat resistance of foam, a method of introducing an isocyanurate bond into a rigid polyurethane foam-constituting polyurethane is well known. In a system using pentane as a foaming agent, the NCO / OH equivalent ratio is about 3.5. Such foams containing a large amount of isocyanurate groups are known (Patent Documents 2, 3, etc.).

  However, even in such a technique, the use of polyether polyol is indispensable for improving the strength of the foam and the adhesion to the face material, and the addition of a flame retardant was indispensable as described above.

JP 2006-335810 A JP 2008-88355 A JP 2008-88356 A

  In view of the above-mentioned problems of the known technology, the present invention does not use polyether polyols or aliphatic polyester polyols, or uses less than 5 parts by weight of polyether polyols or aliphatic polyester polyols. A polyol composition for rigid polyurethane foam that satisfies the standards of quasi-incombustibility without using any flame retardant, or the use of the polyol composition. An object of the present invention is to provide a method for producing a rigid polyurethane foam.

The polyol composition for rigid polyurethane foam of the present invention comprises a polyol compound, a foaming agent and a catalyst, and is a polyol composition which is mixed and reacted with a polyisocyanate component to form a rigid polyurethane foam,
When the total amount of the polyol compound is 100 parts by weight, the aromatic polyester polyol is 95 parts by weight or more,
A high-boiling hydrophilic organic solvent having no active hydrogen group is contained in an amount of 2 to 25 parts by weight based on 100 parts by weight of the polyol compound.

  The rigid polyurethane foam produced using the polyol composition having such a structure has a smaller amount of addition of a flame retardant containing phosphorus and halogen, or meets the standards of semi-incombustibility without using these flame retardants. Suitable rigid polyurethane foam.

  Conventionally, when a rigid polyurethane foam is produced using only an aromatic polyester polyol, the resulting foam has high heat resistance, but the moldability is satisfactory because the flowability of the polyol composition is not good. In addition, physical properties such as low resin strength were insufficient, and the adhesive strength between the foam and the face material to be laminated was not sufficient. For this reason, it was indispensable to add at least 10% polyether polyol to the aromatic polyester polyol. However, the addition of the polyether polyol has a problem that the flame retardancy is lowered, and the addition of the flame retardant is indispensable. Therefore, the environmental demand for reducing the use of phosphorus and halogens could not be met.

  On the other hand, in the present invention, by adding a high-boiling hydrophilic organic solvent that is flammable per se, flame retardancy can be achieved without using a flame retardant such as a halogen-containing compound or a phosphorus-containing compound. The result was improved. Further, when the above composition was used, a rigid polyurethane foam having good physical properties such as resin strength and good adhesive strength between the foam and the face material to be laminated could be formed.

  When the amount of the high-boiling hydrophilic organic solvent added is less than 2 parts by weight based on 100 parts by weight of the polyol compound, the effect is not exhibited, and when it exceeds 25 parts by weight, the flame retardancy of the resulting foam is lowered. The amount of the high-boiling hydrophilic organic solvent added is more preferably 3 to 22 parts by weight with respect to 100 parts by weight of the polyol compound.

The method for producing a rigid polyurethane foam of the present invention is a method of mixing and reacting a polyol composition containing a polyol compound, a foaming agent and a catalyst with a polyisocyanate component to obtain a rigid polyurethane foam,
When the total amount of the polyol compound is 100 parts by weight, the aromatic polyester polyol is 95 parts by weight or more,
The polyol composition includes 2 to 25 parts by weight of a high-boiling hydrophilic organic solvent having no active hydrogen group with respect to 100 parts by weight of the polyol compound.

  According to the manufacturing method of such a configuration, it is possible to manufacture a rigid polyurethane foam that conforms to a semi-incombustible standard in which the amount of a flame retardant containing a halogen is less than conventional or does not contain a flame retardant containing a halogen. it can. Further, a rigid polyurethane foam having good formability and physical properties of the foam and good adhesion strength to the face material can be produced.

  In the method for producing a rigid polyurethane foam, the equivalent ratio (NCO / OH ratio) of active hydrogen groups to isocyanate groups in the mixing of the polyol composition and the polyisocyanate component is 2.5 to 4.5. preferable. The NCO / OH ratio is more preferably 2.5 to 4.0.

  With such a configuration, it is possible to produce a rigid polyurethane foam particularly excellent in flame retardancy.

The density of the rigid polyurethane foam of the present invention is preferably 25 to 60 kg / m ³ . The polyurethane constituting the rigid polyurethane foam of the present invention has a urethane bond and an isocyanurate bond, and also has a urea bond when water is used as a blowing agent component.

  The aromatic polyester polyol used in the polyol composition for rigid polyurethane foam and the method for producing the rigid polyurethane foam of the present invention is a condensate of an aromatic dicarboxylic acid such as phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid and glycol. Yes, it is a polyol compound having an average functional group number of 1.8 to 2.5, more preferably 1.9 to 2.3, and a hydroxyl value of 100 to 400 mgKOH / g. Although it does not specifically limit as glycol which comprises aromatic polyester polyol, It is preferable to use well-known low molecular weight aliphatic glycol as structural components of polyester polyol, such as ethylene glycol, propylene glycol, and diethylene glycol. In the case of a condensate of aromatic dicarboxylic acid and glycol, the number of functional groups is approximately 2, but the number of functional groups can be increased to 2 or more by substituting a part of glycol with a polyfunctional alcohol such as trimethylolpropane. The physical properties of the resulting foam can be adjusted by such a configuration.

  Among the above, as the aromatic polyester polyol, it is preferable to use a polyester polyol having terephthalic acid as a main component, 90 mol% or more of the component constituting the aromatic polyester polyol, more preferably 95 mol% or more, and still more preferably. Preference is given to using aromatic polyester polyols which are all terephthalic acid. The hydroxyl value of the aromatic polyester polyol is more preferably 150 to 300 mgKOH / g, and further preferably 200 to 300 mgKOH / g.

  In the present invention, the polyol compound constituting the polyol composition is preferably composed only of an aromatic polyester polyol, but 5 parts by weight or less of a polyether polyol compound or an aliphatic polyester polyol is contained in 100 parts by weight of the polyol compound. You may contain. As the polyether polyol compound, a ring-opening addition of a cyclic ether compound such as ethylene oxide, propylene oxide, butylene oxide, preferably propylene oxide, or propylene oxide and ethylene oxide to a polyfunctional alcohol compound such as sucrose or glycerin. Examples include aliphatic polyether polyols, aliphatic amine polyols obtained by ring-opening addition of cyclic ether compounds to alkylenediamines and alkanolamines, and aromatic amine polyols obtained by ring-opening addition of cyclic ether compounds to aromatic polyamines such as toluenediamine. it can.

  When a polyether polyol compound or an aliphatic polyester polyol is used as the polyol compound constituting the polyol composition in addition to the aromatic polyester polyol, the flame retardancy decreases, but the moldability and mechanical properties of the foam, adhesion to the face material Sex can be improved. In the present invention, the amount of the polyether polyol or aliphatic polyester polyol used is preferably less than 5 parts by weight, more preferably 4 parts by weight or less, in 100 parts by weight of the polyol compound. It is particularly preferred that

  Examples of the high-boiling hydrophilic organic solvent having no active hydrogen group include ether groups, ester groups, amide groups, etc., which have a boiling point of 100 ° C. or higher, preferably 110 ° C. or higher, more preferably 120 ° C. or higher, which are hydrophilic functional groups. The organic solvent which is a liquid at normal temperature and does not have a hydroxyl group that reacts with an isocyanate group or a primary or secondary amino group can be used without limitation. The hydrophilic organic solvent is more preferably water-soluble that dissolves in an arbitrary ratio with water. Specifically, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, dialkyl ether of polyethylene glycol having a molecular weight of 600 or less, and diethylene glycol diacetate. , Triethylene glycol diacetate, polyethylene glycol diacetate having a molecular weight of 600 or less, diethylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether acetate, polyethylene glycol monomethyl ether acetate having a molecular weight of 600 or less, diethylene glycol monoethyl ether acetate (EDGAC) , Triethylene glycol monoethyl ether acetate, molecular weight 600 or less Monomethyl ether acetate of the polyethylene glycol, .epsilon.-caprolactone, lactone compounds such as γ- butyrolactone, can be exemplified N- methylpyrrolidone.

  In the present invention, as the catalyst, a trimerization catalyst and a tertiary amine catalyst are used in combination and blended in the polyol composition. The catalyst preferably has a trimerization catalyst / tertiary amine catalyst weight ratio of 2/1 to 10/1. The weight ratio of trimerization catalyst / tertiary amine catalyst is preferably 2.5 / 1 or more, and more preferably 3/1 or more. The weight ratio of the trimerization catalyst / tertiary amine catalyst is preferably 8/1 or less, more preferably 7/1 or less.

  Examples of the isocyanurate group-forming catalyst include alkali metal salts of organic carboxylic acids having 1 to 20 carbon atoms such as potassium acetate, potassium propionate, potassium 2-ethylhexanoate (potassium octylate), and N- (2-hydroxypropyl). ) -N- (2-hydroxyethyl) -N, N-dimethylammonium octylate, N-hydroxyalkyl-N, N, N-trialkylammonium salt, etc., disclosed in JP-A-9-104734 Quaternary ammonium salt catalysts such as compounds are exemplified, and commercially available products can also be used, and at least one compound selected from these catalysts is used.

  As the trimerization catalyst (isocyanurate group-forming catalyst), use of an organic carboxylic acid alkali metal salt alone or a combined use of an organic carboxylic acid alkali metal salt catalyst and a quaternary ammonium salt catalyst is preferable. When the organic carboxylic acid alkali metal salt catalyst and the quaternary ammonium salt catalyst are used in combination, the ratio (weight ratio) of the organic carboxylic acid alkali metal salt catalyst / quaternary ammonium salt catalyst is 1/1 or more. It is preferable.

  As the tertiary amine catalyst, a known tertiary amine catalyst can be used without limitation. Specifically, N, N, N ′, N′-tetramethylethylenediamine or N, N, N ′, N N-alkyl polyalkylene polyamines such as' -tetramethylhexamethylenediamine (kaolyzer No. 1), N, N, N ', N', N "-pentamethyldiethylenetriamine (kaolyzer No. 3), diazabicyclone It is preferable to use tertiary amines such as decene (DBU), N, N-dimethylcyclohexylamine (Polycat-8), triethylenediamine, N-methylmorpholine.

  In the polyol composition for rigid polyurethane foam and the method for producing the rigid polyurethane foam of the present invention, the total amount of the trimerization catalyst and tertiary amine catalyst used is the gelation time in the reaction between the polyol composition and the polyisocyanate component. Although it is set as appropriate according to the above, it is preferably 1 to 4 parts by weight per 100 parts by weight of the polyol compound.

  As the foaming agent constituting the polyol composition of the present invention, the use of an HFC compound or the combined use of an HFC compound and water is preferable. Examples of HFC compounds include pentafluoropropane, pentafluorobutane, hexafluorobutane and the like, and in particular 1,1,1,3,3-pentafluoropropane (HFC-245fa), 1,1,1,3,3 Preference is given to using pentafluorobutane (HFC-365mfc), HFC-245fa / HFC-365mfc mixture. When the HFC compound and water are used in combination, the weight ratio of HFC / water is preferably 5 or less, and more preferably 3 or less. When the use ratio of water increases, the concentration of isocyanurate bonds in the polyurethane molecule decreases, and the flame retardancy may decrease.

  In the present invention, a flame retardant can also be added. Suitable flame retardants include metal compounds such as halogen-containing compounds, organophosphates, antimony trioxide, and aluminum hydroxide. Among these, organic phosphates are preferable, and halogenated alkyl ester, alkyl phosphate ester, aryl phosphate ester, phosphonate ester, and the like of phosphoric acid can be used. Specifically, tris (β-chloroethyl) phosphate ( CLP), tris (β-chloropropyl) phosphate (TMCPP), tributoxyethyl phosphate (TBXP), and the like, and one or more of these can be used. The organic phosphates do not need to be added, but when added, the addition amount is 5 parts by weight or less, preferably 4 parts by weight or less, with respect to 100 parts by weight of the total polyol compound. More preferably, it is no more than parts by weight.

  You may use a crosslinking agent as a component which comprises the polyol composition for rigid polyurethane foams of this invention. As the crosslinking agent, low molecular weight polyhydric alcohols used in the technical field of polyurethane can be used. Specifically, trimethylolpropane, glycerin, pentaerythritol, triethanolamine and the like are exemplified.

  The polyisocyanate compound that forms a rigid polyurethane foam by mixing and reacting with the polyol composition is easy to handle, fast in reaction, excellent in the physical properties of the resulting rigid polyurethane foam, and low in cost. For this reason, liquid MDI is used. As liquid MDI, Crude MDI (c-MDI) (Sumijoule 44V-10, Sumijoule 44V-20, etc. (manufactured by Sumika Bayer Urethane Co., Ltd.), Millionate MR-200 (Nippon Polyurethane Industry)), uretonimine-containing MDI (Millionate) MTL (manufactured by Nippon Polyurethane Industry) or the like is used. In addition to liquid MDI, a polyisocyanate compound known in the technical field of polyurethane may be used in combination.

  In producing the rigid polyurethane foam of the present invention, in addition to the above components, foam stabilizers, colorants, antioxidants and the like well known to those skilled in the art can be used.

(Polyol composition)
A polyol composition was prepared with the composition described in the upper part of Tables 1 and 2. In the raw materials used, components other than the components indicated by the compound names are as follows. As a foam stabilizer, in all examples, 5 parts by weight of SH-193 (Toray Dow Corning Silicon) was added to 100 parts by weight of the total polyol compound. The raw materials used are as follows.
a) Aromatic polyester polyol Substantially bifunctional polyol compound having a hydroxyl value of 245 mgKOH / g obtained by condensing terephthalic acid and diethylene glycol b) Polyether polyol Hydroxyl value of propylene oxide added with toluenediamine as an initiator 400 mgKOH / g substantially tetrafunctional polyol compound c) Catalyst quaternary ammonium salt catalyst: Kaulizer No. 410
KAO. No. 1: Kaorizer No. 1 (Kao-No. 1)
d) Foaming agent HFC compound: HFC245fa / HFC365mfc = 80/20 (weight ratio)
e) Polyisocyanate component Sumidur 44V-20 (Suika Bayer Urethane)

(Examples and comparative examples)
For Examples and Comparative Examples, a sandwich panel production line equipped with a foaming machine was used in a conventional manner with the formulations described in the upper part of Tables 1 and 2, and a steel sheet having a thickness of 0.3 mm was laminated as a double-sided face material. A sandwich panel having a foam layer thickness of 50 mm was prepared. The blending ratio was expressed in parts by weight except for the blending amount of the polyisocyanate component. In the catalyst column, T represents a trimerization catalyst, U represents a tertiary amine catalyst, T + U represents the total blending amount, and T / U represents a trimerization catalyst / tertiary amine catalyst weight ratio. The blending amount of the polyisocyanate component was indicated by an isocyanate index (NCO / OH equivalent ratio) in mixing with the polyol component. As the high-boiling hydrophilic organic solvent, water-soluble γ-butyrolactone was used alone, or γ-butyrolactone and diethylene glycol monoethyl ether acetate (EDGAC) were used in combination. As the blowing agent, HFC245fa / HFC365mfc = 80/20 (weight ratio) was used. The compounding amount of the polyisocyanate component is shown as an NCO / OH equivalent ratio. In the calculation of the NCO / OH equivalent ratio, NCO groups were calculated by excluding 2 equivalents of NCO groups consumed by 1 mol of water. The evaluation described below was performed, and the results are shown in the lower part of Tables 1 and 2, respectively.

(Evaluation)
<Cone calorie test>
A sample with a length and width of (99 ± 1) mm × (99 ± 1) mm is cut out from the obtained sandwich panel, and the maximum heat generation when heated at a radiant heat intensity of 50 kW / m ^{2 for} 5 minutes in accordance with ISO-5660. The speed (heat generation rate) and total heat generation were measured. This measurement method is a test method defined as corresponding to the standard according to the corn calorimeter method at the Building Comprehensive Testing Laboratory, which is a public institution prescribed in Article 108-2 of the Building Standard Law Enforcement Ordinance. The standards of quasi-incombustibility are as follows. Those satisfying this standard were determined to pass (go), and those not satisfied were determined to be (not).
B) The total calorific value for 10 minutes is 8.0 MJ / m ² or less.
B) The maximum heat generation rate for 10 minutes should not exceed 200 kW / m ² for 10 seconds or more.
C) There should be no through-holes (cracks, holes) penetrating to the back side, which is harmful to fire prevention, in 10 minutes

<Dimensional stability>
From the obtained sandwich panel, a measurement sample of (99 ± 1) mm × (99 ± 1) mm is cut out and left for 48 hours under high temperature and high humidity conditions (temperature 70 ° C., relative humidity 95%), and the foaming vertical direction The dimensional change rate was measured.

<Surface adhesive strength>("Adhesivestrength" in the table)
Cut out a sample of 100 mm x 100 mm in length and width from the sandwich panel obtained, fix the sample end to the fixed base as shown in Fig. 1, hook the spring balance hook into the hole formed in one upper end of the face material, A peel test was performed by slowly pulling the material in the downward direction at about 45 degrees to determine the adhesive strength (unit: N / 10 cm). The measurement was performed at a temperature of 23 ° C. and a humidity of 65% RH.

<Compressive strength>
The compressive strength was measured according to JIS K 7220. Measurement was performed on 5 samples, and an average value was obtained.

  From the above results, within the scope of the present invention, the obtained rigid polyurethane foam conforms to the quasi-incombustible standard in the corn calorie test, and has dimensional stability, adhesive strength to the face material, and foam. It showed good performance in the compression strength.

  On the other hand, the foam of Comparative Example 1 using 30 parts by weight of polyether polyol with respect to 70 parts by weight of aromatic polyester polyol as the polyol compound did not meet the quasi-incombustible standard by the cone calorie test. The foam using 10 parts by weight of the polyether polyol with respect to 90 parts by weight of the aromatic polyester polyol was also not compatible with the semi-incombustible standard. Further, the foam of Comparative Example 1 had good compressive strength and adhesiveness to the face material, but had poor dimensional stability.

  In Comparative Examples 2 and 3, the addition amount of the water-soluble organic solvent departs from the scope of the present invention. Comparative Example 2 is an example in which the addition amount of the water-soluble organic solvent is 2 parts by weight with respect to 100 parts by weight of the polyol compound, and Comparative Example 3 is an example of 25 parts by weight, both of which meet the quasi-incombustible standard. It was not a thing.

The perspective view which illustrated suitable embodiment of the multifunctional mattress of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Hard polyurethane foam sandwich panel 12 Hard polyurethane foam 14 Face material 16 Spring balance 18 Hole of face material 20 Fixed base

Claims (5)

A polyol composition comprising a polyol compound, a foaming agent and a catalyst, which is mixed and reacted with a polyisocyanate component to form a rigid polyurethane foam,
When the total amount of the polyol compound is 100 parts by weight, the aromatic polyester polyol is 95 parts by weight or more,
See contains 2 to 25 parts by weight based on the polyol compound 100 parts by weight of no high-boiling hydrophilic organic solvent an active hydrogen group,
The catalyst comprises a trimerization catalyst and a tertiary amine catalyst, and the weight ratio of the trimerization catalyst / tertiary amine catalyst is 2/1 to 10/1.
The polyol composition for rigid polyurethane foam , wherein the trimerization catalyst comprises an organic metal carboxylic acid alkali metal salt catalyst and a quaternary ammonium salt catalyst . 2. The polyol composition for rigid polyurethane foam according to claim 1, wherein the organic carboxylic acid alkali metal salt catalyst / quaternary ammonium salt catalyst weight ratio is 1/1 or more . A method for producing a rigid polyurethane foam comprising mixing and reacting a polyol composition containing a polyol compound, a foaming agent and a catalyst with a polyisocyanate component to form a rigid polyurethane foam,
When the total amount of the polyol compound is 100 parts by weight, the aromatic polyester polyol is 95 parts by weight or more,
It said polyol composition, see contains 2 to 25 parts by weight of no high-boiling hydrophilic organic solvent an active hydrogen group to the polyol compound 100 parts by weight,
The catalyst comprises a trimerization catalyst and a tertiary amine catalyst, and the weight ratio of the trimerization catalyst / tertiary amine catalyst is 2/1 to 10/1.
The method for producing a rigid polyurethane foam, characterized in that the trimerization catalyst comprises an organic metal carboxylic acid alkali metal salt catalyst and a quaternary ammonium salt catalyst . The method for producing a rigid polyurethane foam according to claim 3, wherein a weight ratio of the organic metal carboxylate / quaternary ammonium salt catalyst is 1/1 or more . The method for producing a rigid polyurethane foam according to claim 3 or 4, wherein an equivalent ratio of active hydrogen groups to isocyanate groups in the mixing of the polyol composition and the polyisocyanate component is 2.5 to 4.5. .

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