WO1990009271A1

WO1990009271A1 - Production of flame-retardant rebonded foam

Info

Publication number: WO1990009271A1
Application number: PCT/JP1990/000186
Authority: WO
Inventors: Hiroaki Katano; Shigeru Yamaguchi
Original assignee: Dow Mitsubishi Kasei Limited
Priority date: 1989-02-16
Filing date: 1990-02-16
Publication date: 1990-08-23
Also published as: KR910700139A; AU5081990A; JPH02215518A

Abstract

The present invention is directed to a method of producing flame-retardant rebonded foam by bonding the chips of polyurethane foam with one another using a urethane adhesive, characterized by adding 15 to 40 parts by weight of thermally expansible graphite as the flame retarder to 100 parts by weight of the chips. The obtained rebonded foam has a remarkably excellent flame retardancy.

Description

Akira fine. Manual flame retardant Ribonde' Waldorf Wow-time method of production. Technical content field _t

The present invention relates to a method for producing a flame-retardant ribbon dead foam, and more particularly to a method for industrially advantageously producing a ribbon deodorant having extremely excellent twist resistance. Background technology

In the process of manufacturing and forming polyurethane foam, scrap forms including trim, cutting loss, and irreparable products are generated, so effective treatment has been an issue in the past. Conventionally, scraps of soft or semi-rigid polyurethane foam are cut into powder fi or by cutting into chips, and processed into molded products or sheets with urethane-based adhesives, and then bonded. It is used for the same purpose as the Polyurethane Form. Specifically, it is used for carpet underlays, automobile seat cushions, cushioning materials for beds, soundproofing materials, and the like.

On the other hand, a bonded form made of hard polyurethane is manufactured in the same manner as the soft ribbon form, and is used after being processed into a board of a heat insulating material or a molded product.

However, as with soft fi, semi-rigid and hard urethane, the bonded foams made by reusing them also meet various standards when used for applications such as β dynamics and building materials. M Flammability is が Is required.

In order to obtain the desired flame retardancy in ribbon ribbons, the raw materials such as polyurethane foam chips, adhesives, etc. must be selected during the selection of the original foam or the forming process. It is necessary to add a material that can provide flame retardancy. The selection of the original form as a raw material is an important factor in ensuring flame retardancy, but the addition of a flame retardant during molding is a technique that is often used.

Conventionally, the flame retardant added during the molding of ribbon deadforms is tris (2-chloroethyl) phosphate, an additive-type flame retardant that has been widely used in the production of polyurethane foams. And phosphoric acid esters such as tris (2-chloro propyl) phosphate; metal hydroxides such as phosphorylated luminium; antimony trioxide; and inorganic materials such as metal oxides. Flame retardants are widely known.

Among the conventional flame retardant, c ¹ [rho Gen potash phosphate ester is dispersible good for Po Li c Etat Nfu O Muchippu, disadvantageously easily volatilized from manufactured Ribonde' Zadoff O over arm ing. In addition, inorganic flame retardants such as metal hydroxides and metal oxides have a drawback that they are difficult to disperse in polyurethane foam chips. Disclosure of the invention

The present invention solves the above-mentioned conventional problems, and uses a non-volatile flame retardant that is excellent in the effect of improving the flame retardancy and has excellent foam dispersibility. An object of the present invention is to provide a method for industrially producing a bonded form having excellent flame retardancy and other excellent physical properties.

According to the present invention, when a polyurethane foam chip is bonded and processed with a urethane-based adhesive to produce a ribbon deadform, a heat-expandable graphite is used as a flame retardant. The present invention provides a method for producing a flame-retardant ribbon deadform characterized by adding 15 to 40 parts by weight to 100 parts by weight of a chip. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail.

The particle size of the polyurethane foam chip used in the present invention can be variously changed in accordance with the characteristics of the ribbon deadform to be manufactured, but generally, the polyurethane foam having a particle size of about 1 to 1.5 cm is used. A foam tip is used. In the present invention, a cloth such as a wire cloth, a urethane elastomer chip, and other inorganic substances are added to such a polyurethane foam chip in accordance with the characteristics of the target bonded form. Can be added.

On the other hand, as the polyurethane adhesive used in the present invention, a one-component or two-component adhesive can be used. Further, depending on the characteristics of the target bonded foam, a 'foaming type two-pack adhesive' can be used.

The raw materials for urethane-based adhesives include polyisocenes such as aliphatic, alicyclic, aromatic, and complex 3 ^ -type polyisocyanates, and their oligomers and polymers. Ruposi Mido Metamorphosis, Ureta , Denatured phanate modified, isocyanurate modified, or the like can be used alone or in combination of two or more.

Specific examples include fatty acids such as ethylenic isocyanate, 1,4-tetramethylenedicarbonate, 1,6 ^ xamethylenedienediocyanate, and 1,12-dodecanediated sociated acid. Tribe polyisocyanate, cyclobutane 1, 3 — diiso cyanate, cyclohexane 1 1, 3 — and 1 1, 4 — diiso cyanate, isophorone diisocyanate, etc. Cycloaliphatic polysocyanate, m-phenylene ssociate, 2,4-trisylene succinate, 2, 6—trisylene succinate, 2,4 ' —And 4,4 ′ —Aromatic polysocyanates such as diphenylmethandiisocyanate, and mixtures of these oligomers and oligomers, carbodiimides, urethanes, arophanates, Burettes and Lee Seo Shianu rate modified products thereof. In the present invention, 2,4′- and 4,4′-diphenylmethanediisocynates, and mixtures of these oligomers, 2,4— and 2,6—triranges are preferred. An isocyanate and a mixture of these oligomers, and carbodiimide, urethane, arophanate, or a modified isocyanurate of the polyisocyanate are used. Among the polyols that are the raw materials for urethane-based adhesives, polyether polyols include water, ethylene glycol, and water. Ripylene glycol, glycerin, Trimethylo J ref. σ Active hydrogen atoms such as pan, bisphenol A, pentaerythritol J, methyl glycoside, sorbitol, and shucrose Or two or more alkanolamines such as jetanoylamine, triethanolamine, ammonia, ethylamine, ethyleneamine, etc. It has two or more active hydrogen atoms such as diethylenetriamine, tolylenediamine, xylenediamine, diaminodidiphenylmethane, 3,5—getyltridiamine. Amine compounds and Z or their phenolic compounds, such as propylene oxide (hereinafter abbreviated as “P〇”) and ethylenoxide (hereinafter abbreviated as “E〇”). Polyol obtained by subjecting polyalkylene oxide to open JE polymerization, polytetramethylene glycol, and the like can be mentioned.

On the other hand, polyester polyols usually include polycarboxylic acids such as adipic acid, phthalic acid, and trimellitic acid, and ethylene glycols and polyethylene glycols. Examples thereof include those obtained by reacting with polyvalent alcohol such as propylene glycol, butanediol, trimethylolpronodone, and glycerin.

As the polyol, one of these can be used alone or a mixture of two or more can be used.

Among the urethane-based adhesives used in the present invention, as a one-part adhesive, an NC0-terminal polyol-modified isocyanate is widely used. That is, the above-mentioned polyol, preferably a polyhydroxy compound, or a polyether polyol obtained by adding a polyalkylene oxide thereto, or the above-mentioned polyester polyol to the above-mentioned isocyanate. The KC0 content of 5 to 30% by weight obtained by the reaction is used. In this case, if necessary, xylene, toluene, hexane, It can also be used by diluting with an organic solvent such as oral methane or trichloroethylene, or adding an additive such as a coloring agent, a surfactant, an organometallic catalyst, or a plasticizer.

The two-part adhesive is used in a combination of the above-mentioned polyisolate or polyol-modified isocyanate and the above-mentioned polyol. If necessary, the above-mentioned organic solvent, additive, and triethylenediamine, Mineral compounds such as methyl dimethyl, N-methyl remolefin, tetramethylethylene diamine, tetramethyl hexylene dimethylamine, stanaoctate, stanalate, dibutyltin dilaurate It is used by adding a catalyst such as organic gold tin, mercury, and lead compounds.

Such a urethane-based adhesive is used in an amount of 5 to 30 parts by weight based on 100 parts by weight of the polyurethane foam chip. If the amount of the urethane-based adhesive used is less than 5 parts by weight based on 100 parts by weight of the polyurethane foam chip, sufficient bonding cannot be performed. The properties of the resulting bonded foam may be reduced.

The heat-expandable graphite used in the present invention includes, in a broad sense, various compositions produced by various methods. In the present invention, natural graphite, pyrolytic graphite, and kiss graphite are used. It is preferable to use a heat-expandable graphite obtained by treating graphite with a mixture of concentrated sulfuric acid and a strong oxidizing agent, followed by washing with water and drying. The ability to expand several tens to several hundreds times in the C-axis direction due to rapid heating Things. In particular, the heat-expandable graphite used in the present invention desirably has an expansion degree of 50 to 250 cc Zg when rapidly heated at 100 for 10 seconds as a characteristic. For example, in a mixture of 93-99% by weight, especially 98% by weight of concentrated sulfuric acid and 30-60% by weight, especially 60% by weight of hydrogen peroxide, about 20 ~: L00 mesh It is manufactured by contacting crushed graphite with for 10 to 30 minutes with, washing with water and drying.

In the present invention, particularly preferred thermally expandable graphite further includes an alkaline metal such as Na or K or a lithium earth metal such as Ca or M, and the like. The heat-expandable graphite is subjected to acid treatment with the above mixed solution of concentrated sulfuric acid and hydrogen peroxide, washed with water, or in the water washing step, and then subjected to hydroxylation of alkaline metal or alkaline earth metal. By contacting with an aqueous solution of the substance, followed by separation and drying. The aluminum or alkaline earth metal of the heat-expandable graphite Φ obtained in this way is a sulfate, and the PH of the aqueous dispersion having a concentration of 1% by weight of the heat-expandable graphite is 4.5. It is preferable that it is above.

The particle size of such heat-expandable graphite is preferably 30 to 100 mesh from the viewpoints of flame retardant effect and dispersibility in foam. That is, when the particle size of the heat-expandable graphite is smaller than about 80 mesh, the heat-expandability tends to be small, and when the particle size is smaller than 150 mesh, the heat-expandability is extremely reduced. As a result, the flame retardant effect of the foam is reduced. On the other hand, when the degree of S is large, for example, about 20 to 30 mesh, the thermal expansion is sufficiently high, but uniform dispersion in the bonded form is difficult, At the same time, the desired flame retardancy cannot be obtained and at the same time, the work efficiency is reduced due to poor dispersibility in the foam material. Therefore, the particle size of the heat-expandable graphite used in the present invention is preferably 30 to: L00 mesh, and more preferably 40 to 80 mesh.

The particle size of the heat-expandable graphite usually depends on the particle size of the raw graphite used to produce it. Therefore, the adjustment of the particle size can be easily performed by a method such as crushing the raw graphite or the obtained thermally expandable graphite.

In the present invention, 15 to 40 parts by weight of such a thermally expandable graphite is blended with respect to 100 parts by weight of a polyurethane foam chip. ^ If the compounding amount of the expandable graphite is less than 15 parts by weight per 100 parts by weight of the polyurethane foam chip, a sufficient effect of improving the flame retardancy cannot be obtained, and if the compounding amount exceeds 40 parts by weight, the bonded form is exfoliated. The adhesiveness and moldability of the system are impaired.

In carrying out the method for producing a flame-retardant bonded foam of the present invention, first, a predetermined amount of a polyurethane foam chip is uniformly dispersed with heat-expandable graphite, and an adhesive is sprayed on. The resulting mixture is uniformly separated and mixed, and the obtained mixture is filled into a molding die or a press after adjusting to a desired molded article density. Then, heat or heated steam is added to the mold or press for 0.5 to more than 10 minutes to perform the adhesive molding. When using heated steam, or when using an organic solvent or the like, it may be necessary to dry the molded product taken out of the molding die or press. -Degree and strength by blending the prescribed M of thermal expansion lead The flame retardancy of the bonded form is greatly improved without causing the deterioration of the physical properties such as. In particular, as a thermally expandable graphite, it contains sulfates of gold and zinc or alkaline earth metal, and has a pll of 4.5% in a 1% by weight aqueous dispersion. When some are used, the effect of improving flame retardancy is remarkably large. Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples as long as the gist of the present invention is not exceeded. The details of the raw materials used in Examples and Comparative Examples are as follows.

Raw materials used

Tip Α: Flammable soft urethane foam tip

(1 to 1.5 cm) Tip B: Flame retardant 软 K urethane foam tip

:

(Diameter: 1 to 1.5 cm) ゥ Resin adhesive: One-part, moisture-curing, poly-modified polyisolate with the following composition

2.4% Tori Range Isolate 80%

~ 20.5 parts by volume 2, 6 — 20%

Number of functional groups: 3, molecular weight: 3,000, PO adduct —— 79.5 Back side dicyclo; remetane 67 parts by weight

C E F: Tris (2-chloroethyl) phosphite Thermal expansive graphite I: Sulfuric acid treated product

Thermal expansive graphite II: lithium-treated product

(Pil in 1% by weight aqueous dispersion is 7) Thermal expansion black, 111: Ammonia treated product The physical properties of the obtained flame-retardant ribbon deadform were measured by the following evaluation test methods.

Evaluation test

Hardness: JISK-6401 (kg / 200 cm)

Tensile strength: JISK-6402 (kg / crf)

Flammability Distance: MVSS-302 (Distance burned: Inch)

Time ! ]: — 302 (when burned! ¾]: minutes)

Examples 1 to 8, Comparative Examples 1 to 6

The heat-expandable graphite or CEF is evenly dispersed in a predetermined amount of a polyurethane foam chip shown in Tables 1 and 2, and the adhesive is uniformly dispersed and mixed by spraying. In the molding die, each was adjusted so as to have the molded article density shown in Table 1 and Table 2, and filled. Next, heated steam was added to the mold for about 5 minutes. Adhesive molding was performed, and the molded article was taken out of the mold and dried.

Tables 1 and 2 show the physical properties of the obtained flame-retardant ribbon dead foam.

Table 1 Example of implementation Comparative example Example

1 2 3 4 1 2 3 A 100 100 100 100 100 100

Step B 100

Adhesive 20 20 20 20 20 20 20

C E F 20

I 20

Π 20 40

black

Lead ffl 20

Form density 42 39 40 41 41 40 40

(kg / m ³ )

Hardness 7.8 7.5 7.6 7.1 7,5 8.0 7.0

(Ι < _ε / 200 οπι)

Tensile strength (kg / crf) 0.31 0.32: 0.31 0.27 0.33 0.31 0.1 Distance (inch) 0.5 0.4 0.4 0.3 13 1.5 1.8 Property hour (min) 0.1 0.1 0.1 0.1 1.2 0.7 0.5

Table 2

According to Tables 1 and 2, it is possible to obtain a ribbon dead foam with extremely excellent flame retardancy by using thermally expandable graphite without deteriorating physical properties such as hardness and tensile strength. It is clear that we can do that.

As described in detail above, according to the method for producing a flame-retardant ribbon deadform of the present invention, by blending a predetermined amount of thermally expandable graphite, the flame-retardant properties are remarkably excellent, and the hardness and mechanical properties are improved. Strength ^ Thus, it is possible to industrially advantageously produce a flame-retardant ribbon dead foam having extremely good physical properties.

In particular, thermal expansion which contains alkali gold and Z or sulfates of alkaline earth metals as thermally expandable graphite, and has a P 1 i of 4.5 or more in a 1 weight concentration water dispersion. In the case of using graphite, the flame retardancy is further improved. Industrial applicability

The method of the present invention can be advantageously used for the production of a lead foam excellent in flame retardancy.

Claims

The scope of the claims

1. When bonding a polyurethane foam chip with a urethane-based adhesive to produce a ribbon deadform, heat-expandable graphite is used as a flame retardant in 100 parts by weight of the polyurethane foam chip. A method for producing a flame-retardant bonded foam, comprising 15 to 40 parts by weight of the composition.

2. The method according to claim 1, wherein the urethane-based adhesive is used in an amount of 5 to 30 parts by weight based on 100 parts by weight of the polyurethane foam chip.

3. The method according to claim 1, wherein the heat-expandable graphite has a degree of expansion of 50 to 250 ccZg when rapidly heated at 100 t for 10 seconds.

4. The method according to claim 1, wherein the heat-expandable graphite contains Alkali metal or Al earth metal.

5. The heat-expandable graphite contains sulfate of alkaline metal or alkaline earth metal, and pli in 1% by weight aqueous dispersion

4. The method according to claim 4, which is not less than 5.

6. The method according to claim 1, wherein the particle size of the expandable graphite is 30 to 100 mesh.