KR20090039473A - Polyesterpolyol and flame-retradant polyurethane using thereof - Google Patents

Abstract

Flame-retardant polyurethane is provided to show excellent flame-retardant characteristic in no need of a flame retardant and maximize cohesive force to metallic panels even through the quantity of flame-retardant materials used is markedly reduced. Flame-retardant polyurethane comprises polyester polyol having a structure unit represented by the formula I. In the formula I, R1 and R2 are identical or different low alkyl groups; and R3 is low alkyl group, low alcohol, epoxy, isocyanate, acid, amine, aziridine, carbamate, melamine, aryl group or acetoacetate group. The polyurethane indicates flame-retardant polyurethane. A flame-retardant polyurethane foam is produced by reacting polymeric MDI to resin premix containing 100.0 parts of polyol, 1.0-3.0 parts of reaction catalyst, 0.5-3.0 parts of trimerization catalyst, 0.5-2.0 parts of silicone surfactant, 0-20 parts of phosphor-based flame retardant and 0-5 parts of water by weight. The polyol is synthesized by using 30-100wt% of polyester and 0-70wt% of polyether polyol.

Description

Polyester polyol and flame retardant polyurethane using the same {POLYESTERPOLYOL AND FLAME-RETRADANT POLYURETHANE USING THEREOF}

The present invention relates to a novel polyester polyol and a flame retardant polyurethane using the same, and more particularly, to a polyester polyol including an isocyanurate group and a flame retardant polyurethane using the same.

In Korea and Japan, the proportion of casualties caused by harmful gases in fires is over 70%. Therefore, when considering that there are many casualties caused by harmful gases generated when a fire occurs inside a building, etc. It is very important to reduce the amount of gas produced.

Accordingly, flame retardancy is required in accordance with environmental regulations for polyurethane rigid foams used in continuous polyurethane panels mainly used for building exterior walls of factories, warehouses, houses and the like.

Conventionally, aromatic polyester polyols are used abundantly in the polyurethane rigid foam for panels. The reason is that the price is low and it shows very good physical properties in the production of rigid foams. Aromatic polyester polyol production is typically made by condensation polymerization of aromatic acids and polyhydric alcohols.

Typically, polyurethane is a polyol solution and an isocyanate solution are prepared separately so that the two-component and isocyanate and polyol solutions in which the polyurethane foam producer mixes each product to produce a polyurethane foam are mixed in one container, and the temperature is There is a one-part product that allows both solutions to react by increasing. Two-component type is used for building construction or sandwich panel manufacturing due to the convenience of work.

Urethane panels used at the beginning are not flame retardant and are vulnerable in case of fire and emit toxic gases. Therefore, due to environmental problems, the regulation of flame retardancy has recently been tightened, and urethane panels also require flame retardancy.

In order to increase the flame retardancy than the existing PUR products, a method of forming isocyanurate groups through the reaction of isocyanates with an excess of isocyanates was studied. Isocyanurate is a structure that thermally decomposes at a high temperature of 280 ° C. or more in a very stable state. Thus, flame retardant polyurethane foams can be produced by producing isocyanurate groups resulting from the use of aromatic polyester polyols having thermally stable aromatic groups and excess isocyanates. However, during the production of urethane, the amount of isocyanurate generated from the excess isocyanate is substantially very small, and the remainder is present as unreacted isocyanate or produces uretidinone structure, resulting in almost no flame retardant effect. .

Therefore, in order to impart flame retardancy of urethane panels, methods for forming a urethane panel by forming isocyanurate using an excess of isocyanate and applying a polyol, a flame retardant, and other organic and inorganic additives have been developed. .

US Pat. No. 4,194,068 describes a process for preparing polyurethane foams using organophosphorus compounds as flame retardants. US Pat. No. 4,025,470 describes a process for preparing polyurethane foams using esters and acids comprising phosphorus compounds. In addition, the technique has been developed to improve the flame retardancy by introducing a halogen-based flame retardant to the polyol to the polyurethane, but it is expensive and lacks the flame retardant effect, it is not widely used due to the large amount of toxic gas in the fire.

As a technique for improving this problem, there is a technique using an organophosphorus flame retardant. The technique of improving the flame retardancy of the polyurethane foam by using an organophosphorus flame retardant has solved the above problems to some extent, but the organophosphorus flame retardant used has a disadvantage in that flame retardancy is deteriorated with time, and thus is not widely used. In addition, if the excessive amount is not used, the effect of improving the flame retardancy is insufficient, and it may be pointed out as a problem that can greatly reduce the physical properties of the polyurethane foam when using the excess.

In U.S. Patent No. 4,407,981, a reactive phosphorus polyol and phosphorus isocyanate, in which a flame retardant is not chemically mixed with polyurethane but chemically bonded, is used. As described above, flame-retardant polyurethanes typified by reactive phosphorus polyols and phosphorus isocyanates are known to have a low flame retardant effect even after a relatively long period of time, and other physical properties are also retained. Flame retardant components used in this prior art are triphenyl phosphine, triphenylphosphate, triarylphosphate esters. Problems of this prior art include that the polyol used must be at least triol, the manufacturing process is too complicated and the cost of the product is too high.

As the technology of the other series and the above-mentioned technology may be a technique disclosed in Korean Patent Publication No. 1980-0000949. This technique aims to improve flame retardancy by applying inorganic polymers such as boric acid compound and perlite as flame retardant to polyurethane. However, this technique is not practical because it not only lacks the effect of improving the flame retardancy of polyurethane, but also has the disadvantage that the physical properties of polyurethane such as adhesion, reactivity, impact resistance, and abrasion resistance cannot be maintained. In addition, this technique is pointed out as a big problem that the flame retardant used is in the form of particles, which greatly reduces the workability by blocking the nozzle for spraying the resin.

In addition, BASF in Germany tried to obtain polyurethane flame retardant by adding calcium carbonate powder to polyol and reacting with MDI. However, the flame retardant effect was not improved. It is not possible.

Accordingly, it is possible not only to manufacture a polyurethane foam having excellent flame retardancy without using a flame retardant, but also to manufacture a product having excellent flame retardancy even when a small amount of flame retardant is used, thereby reducing the amount of harmful gas generated accordingly. The demand for it continues.

It is an object of the present invention to provide new polyester polyols for use in the production of flame retardant polyurethanes.

It is another object of the present invention to provide a process for producing new polyester polyols used in the production of flame retardant polyurethanes.

Another object of the present invention is to provide a novel flame retardant polyurethane.

It is another object of the present invention to provide a novel flame retardant polyurethane production method.

Still another object of the present invention is to provide a manufacturing method which can maximize the physical properties of the polyurethane foam and the adhesion to the metal panel, as well as excellent flame retardancy even without using a flame retardant.

In order to achieve the object of the invention as described above, the polyurethane of the present invention

Formula (I)

(I)

(I)

Wherein R 1 and R 2 are the same or different lower alkyl;

R 3 represents a polyurethane comprising a polyester polyol having a structural unit represented by H, lower alkyl, lower alcohol, epoxy, isocyanate, acid, amine, aziridine, carbamate, melamine, allyl, or acetoacetate group. to provide.

In the present invention, lower alkyl of the formula (I) is straight or branched alkyl having 1-8 carbon atoms, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert -Butyl, pentyl, isoamyl, neopentyl, 2-pentyl, 3-pentyl, hexyl, heptyl and octyl. In addition, the lower alcohol of the formula (I) is a straight or branched alcohol having 1-8 carbon atoms, for example, methyl alcohol, ethyl alcohol, isopropyl alcohol, butyl alcohol, hexyl alcohol.

Although not limited in theory, the polyurethane according to the present invention has a ring-shaped isocyanurate group formed in the urethane foam, and thus becomes very thermally stable, thereby exhibiting excellent flame retardancy of the final urethane foam. Accordingly, it is possible to greatly improve the problems caused by dissipation, deterioration of physical properties, productivity, workability, etc. due to excessive flame retardant.

In the present invention, the polyester polyol is the following formula (I)

(I)

(I)

Wherein R 1 and R 2 are the same or different lower alkyl; R 3 has a structural unit represented by H, lower alkyl, lower alcohol, epoxy, isocyanate, acid, amine, aziridine, carbamate, melamine, allyl, or acetoacetate group.

In the present invention, the polyester polyol preferably has a number average molecular weight of 500 to 4000. If the molecular weight is too small, the molecular weight is too small to cause the collapse of the polyurethane foam occurs, if the molecular weight exceeds the above range it is difficult to apply to the polyurethane foam production due to the sharp rise in viscosity.

In the present invention, the polyester polyol is represented by the formula (II)

Wherein, where R 1 and R 2 are the same or different lower alcohols, R 3 is H, lower alkyl, lower alcohol, epoxy, isocyanate, acid, amine, aziridine, carbamate, melamine, allyl, or acetoacetate The polyol including the isocyanurate, which is a group, may be prepared by dehydration condensation reaction with dicarboxylic acid.

In the practice of the present invention, as the dicarboxylic acid component, for example, phthalic acid, naphthalene carboxylic acid, sodium dicarboxylic benzene sulfonic acid, adipic acid, suberic acid, sebacic acid, aliphatic cyclo 11 carboxyl Acids, or mixtures thereof may be used.

In the present invention, the polyol component is ethylene glycol, 1,2-propylene glycol, triethylene glycol, butanediol, neopentylene glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimentanol, diethylene Diols such as glycol, 1,5-pentanediol and polyethylene glycol can be used.

As used herein, the term “isocyanurate” means a compound having a cyclic structure formed by three isocyanate groups, —NCO.

Specific non-limiting examples of suitable isocyanurates are tris (hydroxyethyl) isocyanurate (THEIC), triglycidyl isocyanurate (TGIC). The isocyanurate is commercially available and available.

In a preferred embodiment of the present invention, the polyfunctional isocyanurate is composed of two or more functional groups alcohol functional group, a kind of polyol, is condensation reaction with the dicarboxylic acid component isocyanurate group in the polyester polyol backbone Will be inserted.

In the practice of the present invention, when the polyester polyol is used for the production of polyurethane foam, 5 to 50% by weight of isocyanurate represented by the formula (II) is present in the polyol used in the production of the polyester polyol. It is preferable to be included in the range of. When the amount of the polyfunctional isocyanurate increases, the viscosity of the polyester increases rapidly, and the polyfunctionality causes a problem that the moldability and physical properties of the polyurethane foam, such as the crushing of the urethane foam, are intensified. If less, the foam will not provide enough flame retardancy.

In this invention, the said polyol and dicarboxylic acid can use the conditions at the time of well-known esterification reaction and polycondensation reaction. For example, when phthalic anhydride is used as the dicarboxylic acid component and triglycidyl isocyanurate is reacted with diethylene glycol, the ester reaction is known alkali metal, alkaline earth metal or zinc, manganese, cobalt, titanium. By using a metal compound such as a catalyst and reacting at a pressure of 1.5 to 6kg / cm ² at a temperature of 180 ~ 240 ℃, the acid value is synthesized to 1 or less to obtain a flame-retardant polyester polyol according to the present invention .

In the present invention, it can be made through a known urethane reaction of the reaction of the polyester polyol and polyisocyanate.

In one embodiment of the present invention, the polyurethane foam can be obtained by flame-retardant by curing the polyester polyol according to the present invention by uniformly mixing a polyisocyanate, a blowing agent, a catalyst and other oil emulsifiers in a short time by foam molding. In one embodiment of the present invention, a flame retardant may be further added during the production of flame retardant polyurethane foam.

In the practice of the present invention, the flame retardant polyurethane foam can be used in combination with other polyols, in order to control the flame retardancy and the physical properties of the final product, preferably polyester polyols free of conventional isocyanurates and / or Or mixed with a polyether polyol. It is also possible to pre-react each of these before mixing some or all of the polyether polyols or polyester polyols with polyisocyanates with other components in the reaction.

As described above, the polyether polyol used in the present invention may use a conventional polyether polyol prepared by addition polymerization of an alkylene oxide and an organic compound having two or more active structures. Examples of the initial material having active hydrogen atoms include propylene glycol, glycerin, pentaerythritol, ethylenediamine and sorbitol. Examples of alkylene oxides include ethylene oxide, propylene oxide, styrene oxide, butylene oxide, and the like. Epichlorohydrin and the like.

In addition, the polyester polyol is obtained by a polycondensation reaction between an initial substance having two or more active hydrogen groups and glycols and polybasic acids, wherein the initial substance having two or more active hydrogen groups is the same as the polyether polyol and polybasic acid. As the example, adipic acid, cipic acid or diglycolic acid can be used. In particular, as the reactive flame retardant, tetrachloro phthalic anhydride or tetrabromer phthalic anhydride can be used. Examples of the glycols include diethylene glycol, ethylene glycol, 1,4-butanediol, neopentyl glycol, trimethylol propane, glycerin, propylene glycol, dipropylene glycol, triethylene glycol, 1,3-butylene glycol, and the like. .

Polyisocyanates are also represented by the general formula of R (NCO) m, where m is an average value between 1.5 and 3, where R is alkyl or aryl or a substituent thereof, for example toluene diisocyanate and diphenyl methyl diisocyanate polyethylene. Polyphenylene diisocyanate, and mixtures thereof.

As the catalyst used in the present invention, an organometallic or amine-based material may be used. As the organometallic-based material, stanus octoate, stanus oleate, and lead octalate may be used. Triethylamine, diethylenetriami, dimethylethanolamine and the like can be mainly used.

In addition, water or a volatile solvent foaming agent may be used as the blowing agent used in the present invention. Examples of such a material include fluorotrichloromethane or methylene chloride, and the silicone oil emulsifier may be selected by selecting a suitable material depending on the purpose of the polyurethane foam.

In one preferred embodiment of the present invention, the flame-retardant polyurethane foam is 100 to 100 parts by weight of a polyol consisting of 30 to 100% by weight of polyester polyols, 0 to 70% by weight of polyether polyols according to the present invention, 1.0-3.0 by weight of a reaction catalyst Parts, 0.5-3.0 parts by weight of trimerization catalyst, 0.5-2.0 parts by weight of silicon foam stabilizer, and 0-20 parts by weight of phosphorus flame retardant. In a resin premix consisting of 0-5 parts by weight of water, a two-component polyol composition for producing a flame-retardant polyurethane foam composed of polymeric MDI is provided.

According to the present invention, a novel polyester polyol capable of improving the flame retardancy of polyurethane and a method for producing the same have been provided.

The polyester polyol according to the present invention contains isocyanurate in the polyol structure, so that it is not necessary to use excess polyisocyanate in order to introduce isocyanurate into the polyurethane. Therefore, it becomes possible to manufacture a flame-retardant polyurethane foam without the foam property deterioration due to the use of an excess of polyisocyanate, that is, a phenomenon that the foam collapse and the adhesive force is not reduced.

Hereinafter, the present invention will be described in detail through examples.

Example

Preparation of Polyester Polyols

Example 1 Polyester Polyol (A)

782 g of phthalic anhydride as acid, 884 g of terephthalic acid, and 195 g of triglycidyl isocyanurate as alcohol, 2031 g of diethylene glycol and 1 g of tetrabutyl titanate as catalyst were added to the reaction flask, and then the reaction temperature was reached at 200-230 ° C. Was reacted through condensation polymerization.

The synthesized polyol has a hydroxyl value of 290, an acid value of 0.5, a viscosity of 17,500 cps / 25 ° C, and a light yellow transparent liquid.

Example 2 Polyester Polyol (B)

782 g of phthalic anhydride as acid, 884 g of terephthalic acid and 370 g of triglycidyl isocyanurate were added to the reaction flask with 1952 g of diethylene glycol and 1 g of tetrabutyl titanate as a catalyst. Was reacted through condensation polymerization.

The synthesized polyol has a hydroxyl value of 285, an acid value of 0.4, a viscosity of 24,000 cps / 25 ° C, and a light yellow transparent liquid.

Example 3: Polyester Polyols (C)

782 g of phthalic anhydride as acid, 884 g of terephthalic acid and 555 g of triglycidyl isocyanurate as alcohol, 1870 g of diethylene glycol and 1 g of tetrabutyl titanate as catalyst were added to the reaction flask, and then the reaction temperature was 200-230 ° C. Was reacted through condensation polymerization.

The synthesized polyol has a hydroxyl value of 285, an acid value of 0.7, a viscosity of 30,500 cps / 25 ° C, and a light yellow transparent liquid.

Example 4: Polyester Polyols (D)

782 g of phthalic anhydride as acid, 884 g of terephthalic acid and 730 g of triglycidyl isocyanurate as alcohol, 1791 g of diethylene glycol, and 1 g of tetrabutyl titanate were added to the reaction flask, and the reaction temperature was 200-230 ° C. Was reacted through condensation polymerization.

The synthesized polyol has a hydroxyl value of 290, an acid value of 0.7, a viscosity of 40,000 cps / 25 ° C, and a light yellow transparent liquid.

Comparative Example 1: Polyester Polyol (E)

782 g of phthalic anhydride with acid, 884 g of terephthalic acid, 1615 g of diethylene glycol with alcohol, and 1 g of tetrabutyl titanate with catalyst were placed in a reaction flask, and the reaction temperature was raised to 200-230 ° C. to react through condensation polymerization. .

The synthesized polyol has a hydroxyl value of 285, an acid value of 0.6, a viscosity of 70,000 cps / 25 ° C, and a light yellow transparent liquid.

Preparation of Polyurethane Foam

Example 5

Each of the polyester polyols, the catalyst, the flame retardant, the foam stabilizer, and the blowing agent were mixed in the compositions shown in Table 1 below to prepare a resin premix while varying the polyester polyols (A) to (F). Then, 200 g of resin premix adjusted to 20 ± 1 ° C. and polyisocyanate adjusted to 20 ± 1 ° C. were mixed to calculate the weight ratio to index 250 and added to 450 g, and vigorously stirred for 5-7 seconds, followed by 200 mm * 200 mm * 200mm aluminum mold is injected to check the reactivity and appearance and shape of the foam.The mixed solution is injected into an aluminum mold of 250mm * 300mm * 50mm to form a polyurethane foam and after one day, the strength, thermal conductivity and dimensional stability Was measured. The flame retardancy is made of 220mm * 220mm * 40mm aluminum mold size for the production of specimens of 220mm * 220mm * 40mm, the size prescribed by KSF 2271, and laid under 0.5mm thick iron plate and foamed with the raw material of foam. The cover was closed to completely seal the mold cover, and the flame retardant performance was evaluated after fabrication of the test piece. Compressive strength was performed by ASTM D-1621, dimensional stability was evaluated by ASTM D-2126, and flame retardancy was evaluated by KSF 2271 surface test and gas hazard test.

Claims (10)

Formula (I)

(I) Wherein R 1 and R 2 are the same or different lower alkyl; R 3 is a polyurethane comprising a polyester polyol having a structural unit represented by H, lower alkyl, lower alcohol, epoxy, isocyanate, acid, amine, aziridine, carbamate, melamine, allyl, or acetoacetate group. The polyurethane of claim 1, wherein the polyurethane is a flame retardant polyurethane. Formula (I)

(I) Wherein R 1 and R 2 are the same or different lower alkyl; R 3 is a polyester polyol having a structural unit represented by H, lower alkyl, lower alcohol, epoxy, isocyanate, acid, amine, aziridine, carbamate, melamine, allyl, or acetoacetate group. 4. The polyester polyol according to claim 3, wherein the polyester polyol has a number average molecular weight. 30 to 100% by weight of polyester polyol according to claim 3, 100 parts by weight of polyol consisting of 0 to 70% by weight of polyether polyol, 1.0 to 3.0 parts by weight of reaction catalyst, 0.5 to 3.0 parts by weight of trimerization catalyst, silicone foam stabilizer 0.5-2.0 parts by weight, phosphorus flame retardant 0-20 parts by weight. A flame retardant polyurethane foam prepared by reacting a resin premix consisting of 0-5 parts by weight of water with a polymeric MDI. It is represented by the following formula (II),

Wherein R 1 and R 2 are the same or different lower alcohols, The R3 is a dehydration condensation of a polyol containing isocyanurate which is H, lower alkyl, lower alcohol, epoxy, isocyanate, acid, amine, aziridine, carbamate, melamine, allyl, or acetoacetate group; Reacting to produce a polyester polyol. The method of claim 6, wherein the polyol comprises 5-50% by weight of isocyanurate. The method of claim 6, wherein the dicarboxylic acid is selected from the group consisting of succinic acid, adipic acid, fumaric acid, maleic acid, and azelaic acid to produce a polyester polyol. Formula (I)

(I) Wherein R 1 and R 2 are the same or different lower alkyl; R3 is a polyester polyol having a structural unit represented by H, lower alkyl, lower alcohol, epoxy, isocyanate, acid, amine, aziridine, carbamate, melamine, allyl, or acetoacetate group; Process for producing polyurethane. The process of claim 9, wherein the polyisocyanate is selected from the group consisting of aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates.