JPS5938965B2 - Flame retardant isocyanate foam - Google Patents

Description

[Detailed description of the invention] This invention relates to flame retardant isocyanate foams.

More specifically, it relates to a flame-retardant foam obtained by applying the reactivity of isocyanates. Conventional foams obtained by applying the reactivity of isocyanate include polyurethane foam obtained in the process of polyurethane bond formation through the reaction of polyisocyanate and polyol, and polyurethane foam obtained in the process of polyurethane bond formation and isocyanate trimerization reaction. In addition to the polyurethane-modified isocyanurate foam obtained by this method and the polyisocyanurate foam obtained only by the trimerization reaction of isocyanate, polyimide, polyamide, polycarbodiimide, polyurea, and polyoxazolidone bonds are added to these foams to form foams. A variety of foams are known that are introduced prior to reaction or foam formation.

Typically, the production of these foams involves the presence of an isocyanate and a blowing agent, optionally one or more compounds capable of reacting with the isocyanate, such as polyols, epoxy compounds, polycarboxylic acids, acid anhydrides, etc. In addition, catalysts, surfactants, flame retardants, and other additives are used as necessary.

All of these various foams can be made flame retardant to a certain extent depending on the type of material used. In particular, isocyanurate foams obtained by trimerization of isocyanates have good flame retardancy. The present inventors continued their research with the aim of further improving the flame retardance of various foams obtained by utilizing the reactivity of isocyanates. It has been found that by adding an organic amine metal complex selected from the following, the flame retardancy of the resulting foam, particularly the surface flame retardance and flame resistance, can be significantly improved.

It is therefore an object of the present invention to provide isocyanate-based foams with improved flame retardancy, in particular with improved surface flame retardancy and flame resistance; In some cases, at least one type of polyol, epoxy compound, polycarboxylic acid, acid anhydride, and other compound capable of reacting with isocyanate is present, and if necessary, a catalyst, a foam stabilizer, and other auxiliary agents are present. When producing foam by applying the reactivity of isocyanate, adding a soluble organic amine metal complex selected from copper, nickel, lead, cobalt, manganese, zinc and chromium to the foam production stock solution. achieved by.

Next, the present invention will be explained in detail.

The particular organic amine metal complex used in this invention must be soluble in the foam making stock solution.

Specifically, for example, when adding an organic amine metal complex during foaming, if the complex is a powder, foaming stock solutions other than polyisocyanate, such as polyols, catalysts, surfactants, and in some cases flame retardants, may be added. It is best to dissolve it before use. In addition, if it is not soluble in these single components, it may be soluble in a mixture of these components, so in such cases it is preferable to dissolve it in the mixture. When the above complex is in liquid form, it may be added directly. The point is that after foaming, most of the added organic amine metal complex should be uniformly dispersed in the foam at the molecular level or react uniformly with the isocyanate.

For foams using polyols, in some cases an organic amine metal complex may be synthesized in the polyol as a foam raw material, and as long as it is dissolved in the polyol, it may be used as it is as a foam raw material.

Next, the organic amine compound and metal that form the organic amino metal complex used in the present invention will be explained.

The organic amine that forms the organic amine metal complex of the present invention must form a complex with a specific metal compound, and the complex must be soluble in the foam production stock solution.

Specifically, alkyl monoamines (a) such as methylamine, ethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, t-butylamine and hexylamine, N-methylethylenediamine, N,N- dimethylethylenediamine, N,N
, N', N'-tetramethylethylenediamine, etc.
Alkyl-substituted alkylene diamines (b), 1,3-propanediamine, 1,2-propanediamine, 1,4-
Alkylene diamines such as butanediamine, 1,5-pentanediamine, 1,6 hexanediamine, C3 or higher alkylene polyamines such as diethylenetriamine and triethylenetetramine c), monoethanolamine, diethanolamine, triethanolamine, 1-amino Examples include alkanolamines (6) such as propan-2-ol, N-hydroxyethylethylenediamine and N-hydroxypropylethylenediamine, and aromatic monoamines (e) such as aniline, methylaniline and aminophenol. On the other hand, metals that form complexes with these organic amines and contribute to flame retardation include copper, nickel, lead, cobalt, manganese, zinc, and chromium, with copper, nickel, lead, and cobalt being particularly preferred.

The method for producing the organic amine metal complex used in the present invention is not particularly limited, and can be synthesized according to conventional methods.
．． For example, when synthesizing triethylenetetramine copper acetate, copper acetate is dispersed in methanol, triethylenetetramine is added thereto, and the mixture is stirred. The copper acetate gradually disappears and a deep blue solution is obtained. The coordination state of the organic amine in the complex can be easily estimated by taking a visible or ultraviolet spectrum, which gives a spectrum with a peak at an absorption wavelength of 615 mμ. Representative examples of organic amine metal complexes include the following. Those obtained from alkyl monoamines and metal salts include methylamine copper acetate, ethylamine copper acetate, n-probylamine copper acetate, n-propylamine copper benzoate, n-propylamine nickel acetate, and n-butylamine copper acetate. acetate, n-butylamine cobalt acetate, isobutylamine copper acetate, hexylamine copper acetate, and the like.

Those obtained from N-alkyl-substituted alkylene diamines or C3 or higher alkylene polyamines and metal salts include N,N,N/,N'-tetramethylethylenediamine copper acetate, N,N-dimethylethylenediamine copper acetate, 1,3-propanediamine copper acetate, 1,2-propanediamine copper acetate, 1,6-hexanediamine lead acetate, diethylenetriamine copper acetate, diethylenetriamine manganese acetate, diethylenetriamine cobalt acetate, triethylenetetramine copper acetate, triethylenetetramine Examples include zinc acetate. Examples of products obtained from alkanolamines and metal salts include monoethanolamine copper acetate, monoethanolamine cobalt benzoate, diethanolamine copper acetate, 1-aminopropan-2-ol copper acetate, and N-hydroxyethylethylenediamine lead acetate. Can be mentioned. Examples of those obtained from aromatic amines and metal salts include aniline copper acetate, methylaniline copper acetate, and aminophenol copper acetate.

Next, regarding the amount of the organic amine metal complex added, if it is added in too large a quantity, the foaming speed may become too high or the formed foam may become brittle.

Furthermore, if the amount is too small, the flame retardant effect will be small. Therefore, the practically effective range of the amount of the organic amine metal complex added is 0.5 based on the total amount of the metal complex and the isocyanate or polyol reactive with it, specifically, the foam production stock solution. ~30% (the same applies below the weight ratio), preferably 1 to 1
0%, more preferably in the range of 2 to 8. As mentioned above, the organic amine metal complex needs to be soluble in the foam stock solution, and the organic amine metal complex must be soluble in the foam production stock solution at a concentration of 0.5 (
f) It is desirable that all of the above, preferably all added, dissolve.

Addition of an insoluble organic amine metal complex to the foam stock solution, such as ethylenediamine copper dichloride, ethylenediamine copper sulfate, ethylenediamine iron chloride, or ethylenediamine iron acetate, hardly improves the flame retardance.

Isocyanates that can be used in the present invention include diphenylmethane diisocyanate (MDl), polyphenylene polymethylene polyisocyanate (crude MDI), 2,4
-tolylene diisocyanate (2,4-TDI), 2,
Aromatic polyisocyanates such as 6-tolylene diisocyanate (2,6-TD) and xylylene diisocyanate (XDI), aliphatic polyisocyanates such as hexamethylene diisocyanate, and alicyclic polyisocyanates such as isoborone diisocyanate. Organic polyisocyanates used in ordinary urethanization reactions can be used alone or in combination of two or more.

Polyurethane foam with addition of organic amine metal complex,
Polyols that can be used in urethane-modified isocyanurate foams, urethane-modified carbodiimide foams, etc. may have any range of hydroxyl value as long as they are normally used in the production of polyurethane, but the organic amine metal complexes used in the present invention are Particularly preferred is hydroxyl value 100, which is used in the manufacture of general rigid polyurethane foams, since it is particularly effective in making rigid foams flame retardant.
It is preferred to use polyether polyols, polyester polyols, or mixtures thereof within the range of .about.800.

Typical examples of polyether polyols include polypropylene ether glycol, polyethylene polypropylene ether glycol, polytetramethylene ether glycol, polypentamethylene ether glycol, polyhexamethylene ether glycol, polyoctamethylene ether glycol, bisphenol A and propylene oxide or ethylene oxide. Polyether glycols such as glycols having an aromatic ring obtained by adding
and glycol, alkylene oxide, substituted derivatives thereof, or mixtures thereof, sucrose, sorbitol, styrene-vinyl alcohol copolymer, hexanetriol, pentaerythritol, glycerin, trimethylolphenol, trimethylolpropane, 1, 4
- Branched polyether polyols obtained by reacting materials such as butanediol, ethylenediamine or similar compounds thereof in the presence of suitable catalysts. Also,
Typical examples of polyester polyols are those made from dibasic carboxylic acids and polyhydric alcohols.

Dibasic carboxylic acids useful for making this polyester are those that do not have any active hydrogen-containing functional groups other than their carboxyl groups; specific examples include phthalic acid, terephthalic acid, isophthalic acid, succinic acid, and glutaric acid. Acids such as , adipic acid, pimelic acid are suitable. These acid anhydrides can also be used. Among the forms to which an organic amine metal complex is added, the compound having a carboxyl group used in the production of an amide-modified or amide-urethane-modified isocyanurate foam is a compound having a carboxyl group and a combination of the dibasic acid and the dibasic acid with a polyhydric alcohol. These include polyesters having carboxyl groups at the ends, which are obtained by reaction.

To produce an amide-modified foam, these dibasic carboxylic acids are reacted with isocyanate, which is the main raw material used, to synthesize an amide prepolymer having isocyanate groups at the terminals. A method for preparing a foam in the presence of an organic amine metal complex, a trimerization catalyst, a blowing agent, a surfactant, and in some cases a polyol, namely, a prepolymer method, and a dibasic carboxylic acid as a dibasic carboxylic acid component. There is a method in which it is added directly to the stock solution for foam production, ie, a one-step method.

When using the one-stage method, if the dibasic carboxylic acid used is a solid, it is preferably used after being dissolved in a polyol or the like. The process included in the present invention, i.e. the production of polyimide-modified or polyimide-urethane modified isocyanurate foams with the addition of organic amine metal complexes, involves the reaction of isocyanates with acid anhydrides; Typical examples include trimellitic anhydride, biromellitic anhydride, benzophenonetetracarboxylic anhydride, and the like. To produce an imide-modified foam using these, these acid anhydrides are reacted with isocyanate in advance to synthesize a prepolymer containing an imide bond and having an isocyanate group at the end. As a component, it can be produced in the same manner as the above-mentioned amide-modified or amide-urethane-modified isocyanurate. Among these various foams, foams using polyols have the greatest flame retardant effect when the NCO/OH equivalent ratio is 1 to 3, and are superior to conventionally used halogen-phosphorus flame retardants. have

For those with NCO/0H greater than 3, that is, the urethane-modified isocyanurate foam, the flame retardant effect is not as remarkable as when added to urethane foam, but conventional halogen-phosphorus flame retardants There is no decrease in heat resistance, especially high-temperature dimensional stability, as is the case with the addition of Inorganic cobalt ammine complex CcO (RSJI-[3)5 as a flame retardant for foams used in combination with polyols
CUCI2 is JournalOfCellularpl
astics? July/Aug-Ust, l97l2
As reported on page O3, this product does not dissolve in the foam production stock solution, and its flame retardant effect is extremely small compared to organic amine complexes.

Regarding the catalyst used in making the foam according to the present invention, in the case of urethane foam, the organic amine metal complex acts as a urethanization catalyst to obtain the foam without using a conventional urethanization catalyst. However, if a urethanization catalyst is added, the reaction will proceed more smoothly.
Examples of the urethane-7-forming catalyst include organic tin compounds, phosphine, and tertiary amines. Specific examples of the above tertiary amines include triethylamine, triethylenediamine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N/-tetraethylethylenediamine, N-methylmorpholine, 1,1 , 3,3-tetramethylguanidine, N,N,N',N'-tetramethyl-1
, 3-butanediamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, and the like.

In addition, as a catalyst for producing various modified isocyanurate foams including isocyanate trimerization reaction or pure isocyanurate foam as a method for producing foams, alkaline alcohols such as polypropylene glycol sodium salt derived from polypropylene glycol are used. lard, potassium benzoate, sodium acetate, potassium oleate, alkali metal salts such as potassium salts of polymerized linseed oil fatty acids and N,N',N'L tris(dialkylaminoalkyl)-Sym-hexahydrotriazine, 2, 4,6-tris(dimethylaminoalkyl)
All known trimerization catalysts are effective, such as phenol, tertiary amines such as triethylene diamine, etc., and these may be used alone or in mixtures. Furthermore, it is even more effective to use an epoxy compound in combination with these trimerization catalysts.
Epoxy compounds used in this case include substituted monooxides such as shrimp chlorohydrin, allyl glycidyl ether, phenyl glycidyl ether, glycidyl methacrylate, styrene oxide, propylene oxide, butadiene monoxide, diglycidyl ether, and bisphenol A. Examples include glycidyl ethers such as diglycidyl ether. In the present invention, during foam production, a surfactant may be added to help homogenize the components of the reaction mixture and adjust the cell structure of the resulting foam.

Suitable surfactants include silicon-containing compounds such as polysiloxane-polyoxyalkylene copolymers and other organopolysiloxanes. Also effective as surfactants are oxyethylated alkylphenols, oxyethylated aliphatic alcohols, and block copolymers of ethylene and propylene oxide. The blowing agents used in carrying out the present invention include:
Also included are gaseous substances such as CO2 produced by adding water to the reactant mixture or externally added CO2, N2, and mixtures thereof.

Other preferred blowing agents include low boiling liquids that evaporate due to the heat of reaction generated during foam formation. Boiling point -
Fluorinated and/or chlorinated hydrocarbons with temperatures between 50°C and +110°C are well-compatible blowing agents; representative examples of such are trichloromonofluoromethane, dichlorodifluoromethane, and dichloromonofluoromethane. , monochlorodifluoromethane, dichlorotetrafluoroethane, 1,1,2-trichloro-1,2,2-trifluoroethane, dibromofluoromethane, monobromotrifluoroethane, and the like. In addition, benzene, toluene, methylene chloride, hexane, etc. are also used.
These blowing agents can be used alone or in combination. In the present invention, a flame retardant may be added depending on the case.

As such flame retardants, those used in ordinary polyurethane foams, urethane-modified isocyanurate foams, etc. are effective. Typical examples include halogenated organic phosphorus compounds such as tris(chloroethyl)phosphate, tris(dichloropropino(ha)phosphate), and tris(dibromoprobil)phosphate, and inorganic flame retardants such as antimony oxide. Next, examples of the present invention and production examples of raw materials thereof will be described, but the present invention is not restricted by these examples unless it deviates from the gist thereof.

Production example of organic amine metal complex Production example After adding the metal salt shown in Table 1 to 200 ml of methanol and stirring, add the organic amine shown in Table 1 and stirring again, and when no precipitate is observed. The resulting solution was filtered, and the slurry was concentrated using an evaporator to obtain an organic amine metal complex.

Table 1 shows the types and amounts of metal salts and organic amines and the method for confirming complex formation. Example 1 PAPl35 (polymethylene-polyphenylene-polyisocyanate, NCO equivalent: 1) as polyisocyanate
35, manufactured by U.S.A.), Sc as a polyol
-1000 (sucrose type 3 polyether polyol, 0H value 449, manufactured by Asahi Denka Co., Ltd.), N, N' as a catalyst
, N〃Tris(dimethylaminopropino(c)-Sy
m-hexahydrotriazine (hereinafter abbreviated as HHT)
, SH-193 (silicon-based surfactant,
(manufactured by Toray Industries, Inc. 1), using trichloromonofluoromethane (hereinafter abbreviated as R-11) as a blowing agent, and adding the organic amine metal complexes synthesized in Production Examples 1 to 13 above to form a foam with an equivalent ratio of 2 as described below. They were made using the blending ratios shown in Table 2, and the amount added and surface flammability were investigated.

The first result is shown in Table 3. The surface flammability test in Table 3 was conducted by the Journal of Cellular Plastics (JOU).
rnalOfCellularPlastics)19
The test was carried out using the Butlar Chimney test described on page 497 of the November 1967 issue. 11 as liquid A, the other components as liquid B, A
, B are sufficiently mixed in advance, and when foaming, these two
The liquids were combined and rapidly stirred with an electric drill to foam.

Example 2 The complex of basic copper acetate and monoethanolamine obtained in Production Example 11 was added to the formulation of Example 1, and as a comparative example, an inorganic complex insoluble in the foam production stock solution and a halogen-phosphorus complex were added. A foam containing trischloroethyl phosphate (CLP) as a retardant was prepared, and a surface flammability test and a flame penetration test were conducted.

The results are shown in Table 4.

The flame penetration time, which indicates flame resistance, is determined by the Bereau of Mines Flame Ventration Test described in the Journal of Cellular Plastics, March 1968 issue.
Penetration test).

Claims (1)

[Scope of Claims] 1. Polyisocyanate and a blowing agent, optionally at least one of polyols, epoxy compounds, polycarboxylic acids, acid anhydrides, and other compounds capable of reacting with the isocyanate, and optionally a catalyst, An isocyanate foam obtained by reacting a foam production stock solution consisting of a foam stabilizer and other auxiliary agents, which contains copper soluble in the stock solution,
The following organic amine groups (a) to (e) of metals selected from nickel, lead, cobalt, manganese, zinc and chromium
A flame-retardant isocyanate foam made by adding an amine selected from the following and a metal complex to the stock solution. Organic amine group (a) Alkyl monoamines (b) N-alkyl substituted alkylene diamines (c) C
_3 or more alkylene polyamines (d) Alkanolamines (e) Aromatic monoamines 2 In the flame-retardant isocyanate foam according to claim 1, copper, nickel, and lead are soluble in the foam manufacturing stock solution. 1. A flame-retardant isocyanate foam obtained by adding 0.5 to 30% by weight of an organic amine metal complex selected from , cobalt, manganese, zinc, and chromium to a foam manufacturing stock solution. 3. In the flame-retardant isocyanate foam according to claim 1, an organic amine metal complex selected from copper, nickel, lead, cobalt, manganese, zinc, and chromium, which is soluble in the foam production solution, is added to the foam production solution. flame retardant isocyanate foam.