JPH02240125A - Polymer polyol composition and production of foam - Google Patents

Abstract

PURPOSE:To obtain a polymer polyol excellent in dispersibility and cable of markedly shortening the mold release time of a polyurethane foam prepared therefrom by polymerizing an ethylenically unsaturated monomer in a polyol comprising a high-molecular polyol and a low-molecular polyol. CONSTITUTION:A polymer polyol composition prepared by polymerizing an ethylenically unsaturated monomer in a polyol comprising a high-molecular polyol (A) of a hydroxyl value of 20-70 and a low-molecular polyol (B) of a hydroxyl value of 100-1000 and having an average hydroxyl value of 250-400. The high-molecular polyol (A) is one which can be usually used for a polyurethane, and examples thereof include polyether polyols and caster oil. The low- molecular polyol (B) includes a compound of a structure formed by the addition reaction of an active hydrogen compound with an alkylene oxide.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to process X for polymer polyol compositions and rigid polyurethane foams.

[Prior art] A method of manufacturing rigid polyurethane foam by reaction injection molding using polyol for rigid foam is known.

However, with this method, if the molding time of the molded product is shortened, the molded product will swell and cannot be molded. This is because the pressure inside the foam is high due to the low continuity of the foam and the high exothermic temperature. There are ways to increase the continuity of the foam, such as adding more foam stabilizers or using foam stabilizers with weak foam regulating power, but these can make the cell size of the foam uneven and cause molding defects such as voids. bring.

[Problems to be Solved by the Invention] Generally, in flexible polyurethane foams, it is known that a polymer polyol obtained by polymerizing an ethylenically unsaturated monomer in a polyol has a foam communication effect. If a polymer polyol is used as the polyol for use, the dispersibility of the polymer polyol is poor and a large number of particulates are generated, resulting in poor practicality. Furthermore, when a normal polymer polyol and a polyol for rigid polyurethane foam are used together, the polyol becomes unstable and separates or thickens. The present invention has been arrived at as a result of extensive research into polymer polyols that have good polyol stability even when used in combination with polyols for rigid polyurethane foams, and methods for producing rigid polyurethane foams using the polymer polyols.

That is, the present invention comprises a high molecular weight polyol (1) having a hydroxyl value of 20 to 70 and a low molecular weight polyol (2) having a hydroxyl value of 100 to 1000, and has an average hydroxyl value of 250.
A polymer polyol composition for rigid polyurethane obtained by polymerizing an ethylenically unsaturated monomer in a polyol of ~450, and an organic polyisocyanate and a polyol as a blowing agent,
In a method for producing polyurethane foam by reacting in the presence of a foam stabilizer, a catalyst, and if necessary a crosslinking agent and an auxiliary agent, the polymer polyol composition according to claim 1 is used as a polyol to produce a rigid polyurethane foam by a reaction injection molding method. This is a method for producing polyurethane foam, which is characterized by producing foam.

As the polymer polyol (1) used in the production of the polymer polyol in the present invention, those commonly used for polyurethane are used. Examples include polyether polyol, polyester polyol, and castor oil.

Examples of polyether polyols include elliptical compounds in which alkylene oxide is added to active hydrogen atom-containing compounds such as polyhydric alcohols, polyhydric phenols, amines, and polycarboxylic acids.

The polyhydric alcohols include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6
Examples include dihydric alcohols such as hexanediol, diethylene glycol, and neopentyl glycol, trihydric alcohols such as glycerin and trimethylolpropane, and polyhydric alcohols of tetrahydric or higher hydric content such as pentaerythritol, sorbitol, and sucrose.

Polyhydric phenols include polyhydric phenols such as pyrogallol and hydroquinone, as well as bisphenols such as bisphenol A; condensates of phenol and formaldehyde (novolak), for example, US Pat. No. 326,564
Examples include polyphenols described in Specification No. 1.

Examples of amines include ammonia; mono-, di-, and alkanolamines such as triethanolamine, isopropanolamine, and aminoethylethanolamine; C1 to C2. Alkylamines; C2-C6 alkylene diamines such as ethylene diamine, propylene diamine, hexamethylene diamine, polyalkylene polyamines; aliphatic amines such as diethylene triamine, triethylene tetramine; aniline, phenylene diamine, diaminotoluene, xylylene diamine, methylene dianiline , diphenyl ether diamine and other aromatic amines; alicyclic amines such as isophorone diamine and cyclohexylene diamine; aminoethylpiperazine and other heterocyclic amines described in Japanese Patent Publication No. 55-21044.

Examples of polycarboxylic acids include aliphatic polycarboxylic acids such as succinic acid, adipic acid, sebacic acid, maleic acid, and dimer acid, and aromatic polycarboxylic acids such as phthalic acid, terephthalic acid, and trimellitic acid.

Two or more kinds of the above-mentioned active hydrogen atom-containing compounds can also be used. Among these, preferred are polyhydric alcohols and polyhydric phenols having a valence of two or more.

The alkylene oxide added to the above active hydrogen atom-containing compound includes propylene oxide (abbreviated as PO),
Examples include ethylene oxide (abbreviated as EO), butylene oxide, and tetrahydrofuran.

The alkylene oxides may be used alone or in combination of two or more, and in the latter case, block addition or random addition may be used. Among these alkylene oxides, preferred are PO and/or EO.

Examples of polyester polyols include condensed polyester polyols obtained by reacting low-molecular-weight polyols (such as the aforementioned dihydric alcohols, trimethylolpropane, and glycerin) with dicarboxylic acids (such as the aforementioned polycarboxylic acids), and lactones (such as E-cabrolactone). Among the polymer polyols (1), which include polyester polyols obtained by ring-opening polymerization of (1), polyether polyols are preferred.

The hydroxyl value of the polymer polyol (1) is usually 20-70, preferably 20-50. Outside this range, the dispersibility of the polymer deteriorates.

The content of (1) in the total active hydrogen-containing compounds is 5-30% by weight, preferably 7-30% by weight.

Outside this range, the foam becomes soft and the dispersibility of the polymer becomes poor.

Examples of the low-molecular polyol (2) used in the production of the polymer polyol in the present invention include compounds having a structure in which an alkylene oxide is added to the above active hydrogen atom-containing compound.

The hydroxyl value of the low molecular weight polyol (2) is usually 100 to 10.
00 preferably 150-950.

Good rigid foam cannot be obtained outside this range.The content of (2) in the total active hydrogen-containing compounds is 70 to 95% by weight;
Preferably it is 70 to 93% by weight. Outside these ranges, the polymer polyol separates.

The average hydroxyl value of the polyol consisting of the high molecular polyol (1) and the low molecular polyol (2) is 250 to 450, preferably 300 to 450. If it is lower than this range, a good rigid foam cannot be obtained, and if it is higher than this range, the amount of heat generated during foaming increases, so that there is no noticeable effect in shortening the molding time.

In the present invention, if necessary, other active hydrogen-containing compounds may be used in combination in the production of the polymer polyol, and active hydrogen-containing compounds that can be used in combination include C1-C20 alkylamines; C2-C6 alkylene diamines, such as ethylene diamine, propylene diamine, Aliphatic amines such as hexamethylene diamine, polyalkylene polyamines such as diethylene triamine and triethylene tetramine;
Aniline, phenylene diamine, diaminotoluene, xylylene diamine, methylene dianiline, diphenyl ether diamine and other aromatic amines; alicyclic amines such as isophorone diamine and cyclohexylene diamine; Examples include heterocyclic amines described in Japanese Patent Publication No.-21044. The content of these active hydrogen-containing compounds in the total active hydrogen-containing compounds is usually 5% by weight or less, preferably 2% by weight or less, and outside these ranges, the reactivity of the polymer polyol becomes high and foam molding becomes difficult. will occur.

In the present invention, the ethylenically unsaturated monomers include ethylenically unsaturated nitrile [(meth)acrylonitrile, etc.], ethylenically unsaturated carboxylic acid and its derivatives [(meth)acrylic acid, (meth)acrylate, etc.] , aliphatic hydrocarbon monomer [ethylene, propylene, carbon number 4~
20 α-olefins, etc.], aromatic hydrocarbon monomers [
styrene, methylstyrene, etc.], and other vinyl monomers (nitrostyrene, vinyl acetate, etc.).

Preferred is ethylenically unsaturated nitrile alone or a mixture thereof with an aromatic hydrocarbon monomer, and more preferred is (meth)acrylonitrile alone or a mixture thereof with (methyl)styrene.

Radical initiators are usually not used in the production of polymer polyols. Examples of the radical initiator include 2,2'-azobisisobutyronitrile (AIBN), azo compounds such as azodiester polyols, t-butylperoxy-2-ethylhexanoate, t-butylperviparate, etc. peroxides other than those described in Japanese Patent Application No. 59-199160, persulfates, perboronic acids, persuccinates, etc. can be used. Among these, AIBN is preferred.

A chain transfer agent can be used if necessary in the production of the polymer polyol. Examples of chain transfer agents include anolekyl mer-butanes (dodecyl-mer-butane, mercaptoethanol, etc.), alcohols (methanol, 2-
butanol, etc.), halogenated hydrocarbons (carbon tetrachloride, carbon tetrabromide, chloroform, etc.), JP-A-55-31
Enol ethers described in Japanese Patent No. 880 and mixtures of two or more thereof can be used. Among these, preferred are alkyl mer butanes and alcohols.

Suitable usage amounts for the production of polymer polyols are described.

The content of ethylenically unsaturated monomer in the polymer polyol is usually 1 to 50% based on the weight of the polymer polyol,
Preferably it is 5 to 40%. Outside this range, demoldability is poor and the viscosity increases.

When using ethylenically unsaturated nitrile and aromatic hydrocarbon monomer, the mixing weight ratio is usually 95:5 to 50:
50, preferably 90:10 to 60:40. Outside this range, the viscosity increases.

The amount of the radical initiator used is not particularly limited, but is usually 0.5 to 5 parts per 100 parts of the ethylenically unsaturated monomer. If the radical initiator is less than 0.5 part, the polymerization rate will be low5.
Beyond the department. In this case, there is no significant effect on the properties of the polymer polyol.

The amount of chain transfer agent used is ethylenically unsaturated monomer 100%
The amount is usually 1 to 10 parts, preferably 5 to 10 parts. Outside this range, no significant effect is produced.

The method for producing the polymer polyol may be any known method,
For example, a method of polymerizing an ethylenic monomer in the presence of a radical initiator (US Pat. No. 3,383,351, Japanese Patent Publication No. 3
No. 9-24737, Japanese Patent Publication No. 47-47999, Japanese Patent Publication No. 15894-1987, etc.). Polymerization temperature is usually 50
-170°C, preferably 90-150°C.

The polymer polyols of the present invention are used in the production of rigid polyurethane foams.

The organic polyisocyanate used in the production of rigid polyurethane foam in the present invention is one that can be commonly used in the production of polyurethane. For example, aromatic polyisocyanates having 6 to 20 carbon atoms (excluding the carbon in the NGO group) [2,4- and/or 2,6-tolylene diisocyanate (TDI), crude TDI, 2,4
'- and/or 4,4'-diphenylmethane diisocyanate (MDI), crude MDI [crude diaminophenylmethane {condensation product of formaldehyde with an aromatic amine (aniline) or a mixture thereof: diaminodiphenylmethane and a small amount (e.g. 20% by weight) of a mixture with a trifunctional or higher functional polyamine} phosgenated product: polyaryl polyisocyanate (PAPI)], etc.): aliphatic polyisocyanate having 2 to 18 carbon atoms [hexamethylene diisocyanate, lysine diisocyanate, etc.]
: Alicyclic polyisocyanates having 4 to 15 carbon atoms (isophorone diisocyanate, dicyclohexyl diisocyanate, etc.) : Aroliphatic polyisocyanates having 8 to 15 carbon atoms [such as xylylene diisocyanate] : and modified products of these polyisocyanates ( modified products containing urethane group, carbodiimide group, allophanate group, urea group, buret group, uretdione group, urethane group, isocyanurate group, oxazolidone group, etc.):
and polyisocyanates other than the above described in Japanese Patent Application No. 59-199160: and mixtures of two or more of these. Among these, the preferred ones are 2,
4- and 2,6-TDI and mixtures of these isomers, 2,4'- and 4,4'-MDI and mixtures of these isomers, and urethane groups derived from these polyisocyanates, It is a modified polyisocyanate group containing a carbodiimide group, an allophanate group, a urea group, a biuret group, a ure1-dione group, a uretonimine group, an isocyanurate group, and an oxazolidone group, and the NC% is usually 15 to 45%, preferably 20 to 35
%.

The foam stabilizer used in the present invention is usually one for rigid urethane foam. For example L-5420
(manufactured by Nippon Unicar Co., Ltd.), SH-193, SF-2
933 (manufactured by Toray Silicone Co., Ltd.).

As the blowing agent, those commonly used for polyurethane foam can be used. Examples include water, freon, and methylene chloride. Among these, water, freon, and a combination thereof are preferred.

The crosslinking agent used as necessary usually has a hydroxyl value of 3.
00 or more, preferably 400 or more, polyether polyols, aromatic or alicyclic diamines, and mixtures of two or more of these. Among these, aromatic diamines are preferred.

A filler, a coloring agent, etc. can be mentioned as an auxiliary agent that may be used as necessary. Examples of fillers include inorganic fillers such as calcium carbonate.

Regarding the method of tearing rigid polyurethane foam, the range of suitable amounts of each component to be used will be described.

The amount of foam stabilizer is usually 0.1 per 100 parts of the total amount of polyol.
~5 parts, preferably 0.5 to 3 parts. If it is less than 0.1 part, the foam regulating property will be insufficient, and if it is 5 tar, no remarkable effect on the foam regulating property will be observed.

The amount of catalyst is usually 0.01 parts per 100 parts of the total amount of polyol.
-3 parts, preferably 0.05-2 parts. Outside this range, adequate reactivity is not exhibited.

The amount of blowing agent is usually 1 to 2 parts per 100 parts of the total amount of polyol.
0 parts, preferably 1 to 15 parts. Outside this range, the foam density will not be adequate.

The amount of crosslinking agent is usually 10 parts or less, preferably 7 parts or less, based on 100 parts of the total amount of polyol. Outside this range, the typology is poor.

The amount of the auxiliary agent is usually 20 parts or less, preferably 10 parts or less, based on 100 parts of the total amount of polyol.

The NC○ index of the polyurethane foam in the present invention is usually 80 to 130, preferably 90 to 120. A preferred foam cannot be obtained outside this range.

The manufacturing method for rigid polyurethane foam is the same as conventional methods, and either the one-shot method or the prepolymer method (quasi-prepolymer method) can be applied.

An example of the reaction injection molding method is the RIM method, which is known as a method for producing polyurethane resins.

A polyurethane molded article can be produced by a conventional method.

For example, a foam stabilizer, a catalyst, a blowing agent, a crosslinking agent, and an auxiliary agent are added to a polyol and mixed uniformly to form a liquid A, and as a liquid B, an organic isocyanate is prepared in advance. Fill the tank. The injection nozzle of the high-pressure foaming machine is connected to the injection port of the mold in advance, and liquids A and B are mixed with a mixing head and injected into a sealed mold, followed by molding after curing.

[Examples] Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples. Note that parts indicate parts by weight.

The composition of the raw materials used in Examples and Comparative Examples will be explained.

Polyol 1: Polyol added to glycerin and has a hydroxyl value of 673.

Polyol 2: P○ is added to pentaerythritol and the hydroxyl value is 405.

Polyol 3: Polyol added to glycerin and has a hydroxyl value of 280.

Polyol 4: Glycerin with PO added and a hydroxyl value of 170.

Polyol 5: Glycerin with PO and EO added and has a hydroxyl value of 28. (EO is 10% TDA (Diaminoto J Reene (manufactured by Nippon Polyurethane Industry Co., Ltd.)) Amine catalyst: DABCO33LV (33% dipropylene glycol solution of triethylenediamine) Silicone foam stabilizer: SF-2933 (Toray Silicone ( (manufactured by Daikin Industries, Ltd.) Foaming agent: Freon-11 (manufactured by Daikin Industries, Ltd.) Organic polyisocyanate: Millionate MR-100
Performance evaluation of polyurethane foam (manufactured by Nippon Polyurethane Industry Co., Ltd.) is as follows.

Possible demolding time: The shortest demolding time to prevent cracks from forming inside the foam when casting the raw material into a 20 x 10 x 3 cm3 mold.

Density: JIS K6301, compressive strength, curling modulus, curling strength... JIS K7203, heat distortion temperature...
JIS K7207 (4.6 kg load Examples 1 to 3) Table 1 shows the manufacturing method and results of the polymer polyol according to the present invention.
Describe it in It can be seen that the dispersibility is superior to Comparative Examples 1 and 2 of the conventional method.

Examples 4-6 Table 2 shows the manufacturing method and results of polyurethane foams using the polymer polyols prepared in Examples 1-3. Compared to Comparative Examples 3 to 7 using the conventional method, the demolding time was significantly shortened, and other physical properties were also the same or improved.

Comparative Examples 1 and 2 A polymer polyol was prepared in a polyol having a hydroxyl value of 20 to 70 and not containing a polymer polyol. Table 1 shows the results.
Describe it in

Comparative examples 3 to 7 Polyurethane foam was prepared using conventional methods.

The results are listed in Table 3.

Table 1 Table 2 [Effects of the Invention] According to the present invention, a polymer polyol with excellent dispersibility can be obtained, and polyurethane foam using a spoon can be demolded in a significantly shortened time, so it can be used for automobile parts, housings, etc. It exhibits excellent effects.

Claims (1)

[Claims] 1. A high molecular polyol (1) with a hydroxyl value of 20 to 70 and a low molecular polyol (1) with a hydroxyl value of 100 to 1000.
2) A polymer polyol composition for rigid polyurethane obtained by polymerizing an ethylenically unsaturated monomer in a polyol having an average hydroxyl value of 250 to 450. 2. In a method for producing polyurethane foam by reacting an organic polyisocyanate and a polyol in the presence of a foam stabilizer, a catalyst, a blowing agent, and if necessary a crosslinking agent and an auxiliary agent, the polymer polyol composition according to claim 1 is used as the polyol. 1. A method for producing polyurethane foam, which is characterized by producing rigid polyurethane foam using a reaction injection molding method.