JPS5933604B2 - Method for manufacturing flame-retardant polyurethane foam - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing flame retardant polyurethane foam.

Flame-retardant polyurethane foam is used in cushioning materials for automobiles, beds, sofas, etc., and in many other fields.

Conventionally, it has been known to use a combination of zinc oxide, antimony oxide, and finely crushed rogen-containing polymers (e.g., polyvinyl chloride) as a manufacturing method for this type of foam (Japanese Patent Publication No. 1977- 21591). However, such additive-based foams mainly containing halogens not only have difficulty achieving optimal flame resistance when made flexible or semi-flexible at low density, but also have various physical properties. The disadvantage was that it decreased. The present invention
This was developed to eliminate the drawbacks of the conventional methods as described above, and it uses a blowing agent containing a polyether polyol having 2 to 4 hydroxyl groups and a molecular weight of 1000 to 10000, an organic polyisocyanate, and water. is mixed with a surfactant, an organometallic salt catalyst, and a tertiary amine catalyst and reacted by a one-stage method or a prepolymer method to produce a flexible or semi-flexible low-density polyurethane foam, The compound contains 3 to 20 parts by weight of a complex salt of silica zirconate and antimony oxide per 100 parts by weight of the polyether polyol, or further contains 1 to 20 parts by weight of halogen per 100 parts by weight of the polyether polyol. This is a method for producing flame-retardant polyurethane foam, which is characterized by blending a vinyl resin.

The flame-retardant polyurethane foam according to the present invention has a compounding agent of 3 to 100 parts by weight per 100 parts by weight of polyether polyol.
20 parts by weight, preferably 6 to 15 parts by weight of a complex salt of silica zirconate and antimony oxide are used.

Examples of silica zirconate include calcium silica zirconate, magnesium silica zirconate, strontium silica zirconate,
Examples include barium silica zirconate and potassium silica zirconate, and salts of Group Ia compounds of the periodic table are preferred. These complex salts with antimony oxide are obtained by heating and firing a mixture of silica zirconate and antimony trioxide at 650 to 11,000C. The polyol used to produce the polyurethane of the present invention is a primary and secondary hydroxy monoterminated polyoxyalkylene ether having 2 to 4 hydroxyl groups and having a molecular weight of 1,000 to 10,000.

These are liquids or are liquefied or melted during operation in polyurethane foaming equipment or machines. Examples of polyoxyalkylene polyols include linear and branched polyethers that have multiple ether bonds and at least two hydroxyl groups, and are substantially free of functional groups other than hydroxyl groups. included.

Among the polyoxyalkylene polyols useful in the process of this invention are polyethylene glycol, polypropylene glycol and polybutylene glycol. Polymers and copolymers of polyoxyalkylene polyols and block copolymers of ethylene oxide and propylene oxide can also be used. Particularly preferred polyoxyalkylene polyol copolymers include:
Ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, 2-ethylhexanediol-1,3, glycerin, 1,2,6-hexanetriol, trimethylolpropane, trimethylolethane, tris(hydroxyphenyl) ) propane, triethanolamine,
Mention may be made of adducts of triisopropanolamine, ethylenediamine and ethanolamine with ethylene oxide, propylene oxide and butylene oxide. Linear and branched copolymerized ethers of ethylene oxide and propylene oxide are useful in making the foamed products of this invention. At that time, since the terminal is blocked with ethylene oxide, it has a primary hydroxyl group at the terminal in the polymer, and has a molecular weight of about 2,000 to 5,000.
Preference is given to foamed products having a molecular weight of . A more useful type of polyether polyol is a block copolymer obtained from propylene oxide and ethylene oxide.

These polyethers have the following general formulas (A and (B
). [However, during the prison ceremony x + y + z - 20~
Polyethers having a branched chain structure (a+b-20 to 100 in formula 701(B)) are also useful, and such branched chain polyethers are formed by combining the alkylene oxide with a compound having two or more functionalities. obtained from.

Branched polyethers are advantageous for creating cross-linkages between urea or urethane groups and isocyanate groups without interaction. This has the advantage that most of the isocyanate used is available for the release of carbon dioxide and for the reduction of the total amount of isocyanate required to make the foamed polymer. It is also possible to use mixtures of polyether polyols. Similarly, it can also be used as a graft polyol of an ethylenically unsaturated monomer such as acrylonitrile, methacrylonitrile, vinyl acetate, methyl acrylate, etc. and a polyol.

A method for producing such a graft polyol is described in U.S. Pat. No. 330
No. 4273 and No. 3383351.

2-8 in the form composition to increase the cross-linking density.
A cross-linking material having 2 hydroxyl groups can be included.

These have a molecular weight of 60-600. These substances are usually required only in small amounts (approximately 0.3 to 10 moles per 100 moles of polyol). Examples of such cross-linking include ethylene glycol, diethylene glycol, propylene glycol, butanediol-1 and 4, dipropylene glycol, glycerin, trimethylolpropane, butanetriol, hexanetriol, trimethylolphenol, and tris-(hydroxyphenyl)propane. , tris-(hydroxyxylyl)propane, various tetrols such as erythritol and pentaerythritol, pentols, hexols such as dipentaerythritol and sonolevit, and alkyl glycosides, carbohydrates, polyhydroxy fatty acid esters such as castor oil, and Polyoxyalkylated derivatives of polyfunctional compounds with 3 or more reactive hydrogen atoms, such as trimethylolpropane, glycerin, 1,2,6-hexanetriol, Solpit and other polyols, as well as ethylene oxide, propylene oxides or other alkylene oxides or their copolymers, such as the reaction products of ethylene and propylene oxide. Grafted crosslinkers can be prepared, for example, by the method of the aforementioned US patent. The organic polyisocyanates used in the method of the present invention include alkylene diisocyanates such as ethylene diisocyanate, trimethylene diisocyanate, hexamethylene diisocyanate, butylene-1,2-diisocyanate, and cyclopentylene-1,3-diisocyanate.
- diisocyanate, cycloalkylene diisocyanate such as cyclohexylene-1,3-diisocyanate,
m-phenylene diisocyanate, p-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2
・6-Tolylene diisocyanate, naphthalene-1/4
- aromatic diisocyanates such as diisocyanate, aliphatic monoaromatic diisocyanates such as xylylene-1,4-diisocyanate, and bis(4-isocyanate phenyl)methane.

The amount of polyisocyanate used is determined by the total number of moles of active hydrogen in the polyol, crosslinker, water, halogen compounds, and other active hydrogen-containing materials in the polyurethane foam composition.
It ranges from about 0.70 to 1.35 moles.

Water is used as a blowing agent and is about 1.5 to 5 parts by weight per 100 parts by weight of polyol.

If a low density, flexible foam is desired, up to about 25 parts by weight of a fluorocarbon blowing agent per 100 parts by weight of said polyol, such as trichloromonofluoromethane, dichlorodifluoromethane, bromotrifluoromethane,
1,1-difluoro-1,2,2-trichloroethane,
1-chloro-1-fluoroethane, 1,1,1-trichloro-2,2,2-trifluoroethane, etc. can be added. As the polyether polyol-polyisocyanate reaction catalyst, catalysts conventionally used in this field, in particular metal-containing catalysts, are used.

Examples of such catalysts include (1) tertiary phosphines such as trialkylphosphine and dialkylbenzylphosphine, (2) strong bases such as alkali metals and alkali metal hydroxides, and (3) secondary chloride. Acidic metal salts of strong acids such as iron, stannic chloride, stannous chloride, antimony trichloride, bismuth nitrate, (4) acetylacetone, ethyl acetoacetate, etc., and various metals (for example, Be.Hg, Zn.Cd.. Pb,
．． Ti,. Zr. ．． Sn,. Bi,. Cr, M.O. Mn
．． Fe. C.O. metal chelates obtained from (Ni, etc.),
(5) Ti(0R)4, Sn(0R)4, Sn(0R)
2. Alcolades or phenolades such as Al(0R)3 [where R is alkyl or aryl], (6) sodium acetate, potassium laurate, stannous acetate, lead octoate, manganese naphthenate, cobalt naphthenate, etc. Alkali metals, alkaline earth metals, Al. Sn. Pb
．． Mn. CO, Ni. Organic acid salts of metals such as Cu, (7)
Organometallic derivatives of tetravalent tin, trivalent and pentavalent As and Sb, (8) dialkyltin salts of carboxylic acids such as dibutyltin diacetate, dibutyltin dilaurate, dibutyltin-4-methylaminobenzoate, and trimethyl hydroxide. tin,
trialkyltin hydroxides such as cyoctyltin oxide, dibutyltin-bis(isopropoxide), and dibutyltin dichloride;
Examples include dialkyltin oxide, dialkyltin dialkoxide, dialkyltin dichloride, and the like. Preferably 2 or more carbon atoms
It is a divalent tin salt of 18 carboxylic acids. These catalysts are
Approximately 0.1 to 0 per 100 parts by weight of polyether polyol
．． 9 parts by weight are used. A surfactant is required to provide the desired cell formation and growth, and polysiloxane-polyoxyalkylene block copolymers are preferred.

The copolymer is described in US Pat.
No. 917480. In addition, non-hydrolyzable polysiloxane-polyoxyalkylene block copolymers can also be used. This means that the polysiloxane moieties are directly carbon-carbon rather than via carbon-oxygen-silicon bonds.
It differs in that it is bonded to the polyoxyalkylene moiety via a silicon bond. These copolymers usually contain 9 to 95% by weight of polysiloxane polymer, preferably 15 to 50% by weight, and the remainder polyoxyalkylene polymer. The surfactant is used in an amount of about 0.3 to 2.5 parts by weight per 100 parts by weight of poietherpo-1-ol. At least one tertiary amine catalyst is included in the polyurethane compositions of the present invention, preferably along with a metal-containing co-catalyst. The amount of the amine is from 0.05 to 3.2 parts by weight per 100 parts by weight of polyether polyol. When a metal catalyst is used in the urethane foaming reaction, the amine is
．． Preferably, 9 parts by weight are used. On the other hand, tertiary amines cause foaming (H2O+NCO) and structure (-ROH+N
CO) reaction, the tertiary amine is present in an amount of about 0.1 to 2 tertiary amines per 100 parts by weight of polyether polyol.
．． Preferably, 0 part by weight is used. Examples of the tertiary amine used in the present invention include triethylenediamine, triphenylamine, triethylamine, N-
N-ma-mertetramethyl-1,3-butanediamine,
N-methylmorpholine, N-acetylmorpholine, N-
Octylmorpholine, N-phenylmorpholine, N-hydroxyethylmorpholine, trimethylaminoethylpiperazine, trimethylamine, triethanolamine,
Examples include 1,2,4-trimethylpiperazine, N-methyldicyclohexylamine, and mixtures thereof. Other known ingredients, such as barium and cadmium salts of carboxylic acids, clays, talc, TiO2, silicon oxides and hydrated silicon oxides, calcium carbonate, metal chromates, barite, phthalocyanine fringe or color pigments, oxidized hematite,
Conventional stabilizers, carbon black, dyes, toners, epoxidized soybean oil, epoxide (Kohon 828), tricresol phosphate, antioxidants, fungicides, etc. may also be added during polyurethane foam formation.

These components can be added in varying amounts to achieve desired properties in the resulting flexible, low density foam. The flame retardant polyurethane foam according to the invention can be used in many areas such as cushion mattresses, pillows, furniture, automotive cushion products, rugs, headrests, etc.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Note that "parts" in the following Examples and Comparative Examples are by weight unless otherwise specified. Example 1 100 parts of a polyether polyol having an average molecular weight of about 3000, T
-9 catalyst (stannate octoate) 0. }2 parts, 1.0 parts of silicone (polysiloxane-polyoxyethylene alkylene block copolymer) and a powdered complex salt of silicozirconate and antimony oxide8.
0 parts were mixed and stirred.

To this, 3.6 parts of water and 0.2 parts of an amine catalyst (triethylene diamine) were mixed, and 45 parts of tolylene diisocyanate and 4.0 parts of Freon 11 were added to the foaming stock solution while stirring simultaneously in a container. As soon as the reaction starts, it is poured into a foaming mold with a mold temperature of 40℃, and after closing the upper mold,
After foaming and curing at 50°C for 13 minutes, a polyurethane membrane with excellent flame retardancy as shown in Table 1 was obtained. As shown in the measurement results shown in Table 1, the present invention uses a completely new flame retardant, so compared to the conventional flame retardant polyurethane foam (curve B), as shown in the drawings ( Curve A) shows a large value of 25% compressive load (hardness) despite using the same amount of flame retardant.

Therefore, it has the great effect of being able to perform its functions with a foam that has a lower density than conventional flame-retardant polyurethane foams, even though it has the same hardness. Further, when six flame-retardant polyurethane foams were made using the above method and a combustion test was conducted based on MVSS3O2, all six were found to be non-flammable (NB) as shown in Table 2.

Comparative Example In the method of Example 1, tris(dichloropropyl) phosphate [Tris(DichlO
When the same method was carried out except that 8.0 parts of a compound containing mainly PhOsphate] was used, the results shown in Table 1 and the drawing (curve B) were obtained.

Example 2 In a method similar to Example 1, silicone was added to 1.1 parts, tolylene diisocyanate was added to 37.6 parts, and water was added to 2 parts.
．． A flame-retardant polyurethane foam was produced in the same manner except that the amount of the amine catalyst was changed to 9 parts and 0.17 parts, and then the same test as in Example 1 was conducted.
The results shown in Table 3 were obtained.

In this way, in the case of this example as well, the standards can be satisfied without deteriorating the physical properties. According to the present invention, a halogen-containing complex salt of silica zirconate and antimony oxide can also be used. Vinyl fluoride, vinylidene chloride and polymers of these monomers, other halogen-containing vinyl resins, such as copolymers of a large amount of vinyl halide and a small amount of vinyl acetate, are added in an amount of 1 to 100 parts by weight per 100 parts by weight of the polyether polyol.
It is also possible to use 20 parts by weight. Next, a blending example and combustion test results will be shown. Example 3 100 parts of a polyether polyol having an average molecular weight of about 3000, 0.0 parts of a resinization catalyst (stannate octoate).
12 parts, silicone 1.0 part, tolylene diisocyanate 45.0 parts, water 3.6 parts, foaming catalyst (triethylenediamine) 0.2 parts, Freon 11 4.0 parts, powdered silica zirconate A flame-retardant polyurethane foam was produced in the same manner as in Example 1 using 5.0 parts of a flame retardant consisting of a complex salt of and antimony oxide and 6.0 parts of powdered polyvinyl chloride. When similar tests were conducted, the results shown in Table 4 were obtained.

Table 4 As mentioned above, the method for producing flame-retardant polyurethane foam according to the present invention involves a blowing agent containing a polyether polyol having 2 to 4 hydroxyl groups and having the same molecular weight, an organic polyisocyanate, and water. is mixed with a surfactant and a tertiary amine catalyst and reacted by a one-step process or a prepolymer process to produce a flexible to semi-flexible low density polyurethane foam, wherein the 3 to 2 per 100 parts by weight of polyether polyol
Since it is a composite salt of 0 parts by weight of silica zirconate and antimony oxide, or is further blended with 1 to 20 parts by weight of a halogen-containing vinyl resin per 100 parts by weight of the polyol, the This is a chemical reaction type flame retardant method in which a chemical reaction occurs due to heat and exhibits excellent self-extinguishing properties, and can maintain stable flame retardancy over a long period of time.

Furthermore, when making polyurethane foam flame retardant,
Although it affects the physical properties to a greater or lesser extent, the flame-retardant foam obtained by the present invention has almost no adverse effects on the physical properties, and therefore it is possible to make low-density foams flame-retardant, which was previously considered difficult. Therefore, a polyurethane foam which is advantageous in terms of weight reduction and cost reduction can be obtained.

[Brief explanation of the drawing]

The drawing is a graph showing the relationship between the density and 25% compressive load of flame-retardant polyurethane foams obtained by the method of the present invention and the conventional method. A: Curve of the product of the present invention, B: Curve of the conventional product.

Claims (1)

[Claims] 1 A polyether polyol having 2 to 4 hydroxyl groups and a molecular weight of 1000 to 10000, an organic polyisocyanate, and a blowing agent containing water are combined with a surfactant, an organic metal salt catalyst, and a tertiary amine catalyst. Mix 1
A method for producing flexible or semi-flexible low-density polyurethane foam by reacting by a step method or a prepolymer method, wherein 3 to 20 parts by weight of silica zirconate per 100 parts by weight of the polyether polyol is added in the formulation. A method for producing a flame-retardant polyurethane foam, which comprises blending a composite salt of a salt and antimony oxide, or a halogen-containing vinyl resin in an amount of 1 to 20 parts by weight per 100 parts by weight of the polyether polyol.