KR20120060672A - TDI-based Non-yellowish urethane foam and manufacturng method thereof - Google Patents

Abstract

PURPOSE: A manufacturing method of a toluene diisocyanate based non-yellowing urethane foam Is provided to manufacture a non-yellowing urethane foam which is stable against UV discoloration even by using a small amount of UV stabilizer in prescription which uses aromatic isocyanate as a raw material. CONSTITUTION: A manufacturing method of a toluene diisocyanate based non-yellowing urethane foam comprises a step of manufacturing polyurethane foam by mix-blowing a resin premix containing polyether polyol, surfactant and catalyst, and aromatic isocyanate. The OH functional group of the polyether polyol is 3-6, and the molecular weight is 3,000-6,000. The catalyst is organic metal catalyst. The resin premix comprises a phenolic antioxidant and a UV block. The comprised amount of the phenolic antioxidant is 0.5-5 parts by weight, based on 100.0 parts by weight of polyol.

Description

TDI-based non-yellowish urethane foam and manufacturng method

The present invention relates to a TDI-based egg yolk urethane foam and a method for manufacturing the same, and more particularly, to a yolk urethane foam for slabs and a method for producing the same.

Urethane foam using an aromatic isocyanate has a low price and excellent physical properties, and is used in various applications such as expensive garment bra pads, shoe pads, and other exterior materials. However, aromatic urethane foams using toluene diisocyanate or diphenylmethane diisocyanate have a monoquinone imide and diquinone imide structure in which the urethane foam is chromophore by ultraviolet light (10% or less) of 290 to 400 nanometer wavelength. By changing, there is a problem of discoloration and deterioration of physical properties and deterioration of appearance quality due to yellowing.

In order to solve this yellowing phenomenon, a method of using aliphatic isocyanate has been proposed. However, the aliphatic isocyanate has a very good yellowing stability due to ultraviolet rays, but has a problem in that its use is limited due to high raw material prices.

 In addition, as a way to solve the yellowing phenomenon has been developed to introduce ultraviolet stabilizers used to prevent yellowing of other polymer systems.

 U.S. Patent No. 6,767,940 discloses stability against UV discoloration through the use of nitroxy compounds, such as derivatives of 2,2,6,6-tetramethylpiperidyloxy, as a Hals-based UV stabilizer to ensure stable free radicals of elastomeric products containing polybutadiene. The prescription is disclosed.

U. S. Patent No. 6,194, 509 describes the development of a formulation that is stable to UV discoloration through the use of stable free radicals such as derivatives of 2,2,6,6-tetramethylpiperidyloxy to remove radicals from vulcanized elastomeric products.

In U.S. Patent No. 3,554,962, a polyether-based prepolymer synthesized with an aromatic isocyanate has a very stable result against UV rays, especially a product that is cured rapidly under crosslinking or chain extender prescription conditions, and especially an amine curing agent that can affect color. The result which was stable to discoloration even under conditions was described.

U.S. Patent 5,785,916 discloses Hals-based UV stabilizers and benzotriazole-based UV absorbers to improve the UV and UV stability of urethane products.

Japanese Patent 2004-51954 describes the UV discoloration stability, the discoloration stability for nitrate gas, and the water resistance according to the composition change (EO content) of polyol, and the lower the EO content, the UV discoloration stability and discoloration stability for nitrate gas, Excellent water resistance and above 10% of EO content described the experimental results of yellowing resistance, discoloration stability for nitrate gas and poor water resistance.

However, the conventional methods use a large amount of ultraviolet stabilizer or ultraviolet absorber to prevent the discoloration, causing a rise in manufacturing cost. Nevertheless, yellowing is still severe due to prolonged exposure, and there is a continuing demand for reduction thereof.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing egg yolk foam which is stable to UV discoloration even when a small amount of UV stabilizer is used in a formulation based on aromatic isocyanate.

Another object of the present invention is to provide a urethane foam production method that is stable to discoloration under indoor lighting conditions.

It is another object of the present invention to provide a urethane foam production method that is stable to discoloration under solar conditions.

It is another object of the present invention to provide a urethane foam manufacturing method that is stable to discoloration even after prolonged exposure to ultraviolet rays.

Still another object of the present invention is to provide a polyurethane foam having no fogging problem and odor problem, strong discoloration resistance, and improved elasticity and other mechanical properties.

In order to solve the above problems, the polyurethane foam manufacturing method according to the present invention is prepared by mixing and foaming a resin premix containing a polyether polyol and a foam stabilizer and a catalyst and an aromatic isocyanate, wherein the polyether The polyol has an OH functional group of 3 to 6, a molecular weight of 3,000 to 6,000, the catalyst is an organic metal catalyst, and the resin premix is an ultraviolet light composed of a group consisting of a phenolic antioxidant, an ultraviolet absorber, an ultraviolet stabilizer, and a mixture thereof. It is characterized by including an inhibitor.

In the present invention, the phenolic antioxidant is preferably included 0.1-5 parts by weight, more preferably 0.5-3 parts by weight based on 100 parts by weight of the polyol in the premix.

In the present invention, the phenolic antioxidant is preferably a 2 equivalent phenolic antioxidant in which two phenolic groups are formed in one molecule. The phenolic antioxidants are benzene propanoic acid, 3,5-bis (1,1-dimethylethyl) -4-hydroxy-, C7-9-branched alkyl ester, octadecyl-3- (3,5 -Di-t-butyl-4-hydroxyphenyl) propionate, triethylene recall-bis-3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionate and the like can be used, Commercially available for purchase. In a preferred embodiment of the invention, the phenolic antioxidant is S-1135, S-1076, S-2450 and the like of Songwon Industrial.

In the present invention, the anti-UV agent means any one of ultraviolet absorbers, ultraviolet stabilizers, or mixtures thereof.

In the present invention, the ultraviolet absorber is a compound that absorbs light of 200-400 nm. In the present invention, the ultraviolet absorber is preferably included in the resin premix in the range of 0.1-1 part by weight based on 100 parts by weight of the polyol. When the content of the ultraviolet absorbent is increased, it is stable in the initial QUV, but may change color due to by-products such as Knox and Nax over time, resulting in unstable long-term discoloration and excessively low content of the ultraviolet absorbent. In this case, the degree of discoloration due to ultraviolet rays is greatly increased.

In a preferred embodiment of the present invention, the ultraviolet absorber is preferably a benzotriazole ultraviolet absorber, for example, 2- (2'hydroxy-3 ', 5'-di-t-butylphenyl) benzo Triazole, 2- (2'-hydroxy-3 ', 5'-di-t-butylamyl) benzotriazole can be used. It is also possible to purchase and use commercially, for example, S-3200 and S-3280 of Songwon Industries.

In the present invention, the UV stabilizer can be used a Halz-based stabilizer that is a radical scavenger to remove the radicals generated by ultraviolet light to prevent the onset of yellowing. Halus-based UV stabilizers include Songwon Industries S-1190, S-2920, S-6220, S-7700, S-7830, S-7910, and S-9440.

In the present invention, the ultraviolet stabilizer is preferably used in the range of 0.1-2 parts by weight based on 100 parts by weight of the polyol. If the content of the UV stabilizer is out of range, it is difficult to expect the role of the radical scavenger or cause secondary discoloration.

In this invention, the said ultraviolet inhibitor can be used individually or in mixture of the said ultraviolet stabilizer and an ultraviolet absorber.

In the present invention, the polyurethane foam preferably comprises an index of the resin premix and aromatic isocyanate compound containing a polyol in the range of 85-120, more preferably 85-95, most preferably the index is 90 It is good. When the index value is high, the degree of discoloration becomes severe, and when the index value is low, a problem of deterioration in strength or stability of the foam occurs.

In one aspect of the present invention, the polyurethane foam is composed of a polyether polyol having an OH functional group of 3 to 6 and a molecular weight of 3,000 to 6,000 and an aromatic isocyanate, and includes a phenolic antioxidant and a sunscreen, and a yellowed polyurethane foam. Characterized in forming. In the present invention, the ultraviolet absorber is a combination of a benzotriazole ultraviolet absorber and a HALS ultraviolet stabilizer, and the polyol and the isocyanate preferably have an index of about 90.

In a preferred embodiment of the present invention, the method for producing a yolk yellow foam according to the present invention is a polyether polyol having a OH functional group of 3 to 6 and a molecular weight of 3,000 to 7,000, a crosslinking agent, a foam stabilizer, a UV absorber, a phenolic antioxidant and an organic tin. The resin premix containing the catalyst is mixed and foamed with an aromatic isocyanate.

In the present invention, the polyether polyol is not limited in theory, but it is preferable to use a high molecular weight polyol for improving mechanical properties through reaction with an aromatic isocyanate. In the present invention, the high molecular weight polyether polyol preferably has an OH functional group of 3 to 6, more preferably 3 to 5, even more preferably 3.5 to 4.5, and a molecular weight of 3,000 to 7,000 is preferable. When the OH group of the polyether polyol is 3 or less, elasticity, permanent compressive strain reduction and hardness reduction may occur during foam molding, and in the case of 6 or more, problems such as foam shrinkage and hardness increase. In addition, when the molecular weight is less than 3,000, there is a problem that the foam hardness rises and the molding width of the foam is narrowed, and when the molecular weight is 7,000 or more, problems such as flowability and moldability due to viscosity decrease during hardness reduction and urethane reaction may occur.

In the practice of the present invention, the polyether polyol is a polyhydric alcohol such as pentaerythritol, sorbitol, sorbitol diether, mannitol, mannitol diether, arabitol, arabitol diether, sucrose, sucrose and glycerin mixture High functional polyols having at least trivalent hydroxyl groups can be prepared by reacting ethylene oxide and / or propylene oxide with an initiator and can be prepared by known methods.

In a preferred embodiment of the present invention, the content of ethylene oxide in the polyether polyol is preferably used in 5 to 15% by weight, and when the content is 5% by weight or less, the increase in the amount of catalyst used and the foam according to the reaction rate and curability deterioration problem It may affect the molding stability during processing, and when the ethylene oxide content is 10 parts by weight or more, there is no effect on reactivity, curability, and the like.

In the present invention, the foam stabilizer is used to control the cell uniformity and the size of the foam, it is preferable to use a silicone foam stabilizer. In the practice of the present invention, the silicone foam stabilizer is preferably used in an amount of 0.1 to 3 parts by weight based on 100 parts by weight of the polyol, and may cause foam shrinkage when the amount is excessively used. In the practice of the present invention, the foam stabilizer can be purchased commercially and used, for example, B8002, B4900, B8128, B8462, B8123 from Degussa or DABCO DC 193, DC 5043, DC 5388, DC 5169 from Air Products. Alternatively, Momentive's L580, L5740M, L6900, L2100, L3002 and the like can be used.

In the case of using the polyether polyol according to the present invention, in the case of a polyol having a low EO content, foam openness may increase while foam openness may increase, thereby increasing the openness of the cell, and thus preventing the shrinkage of the slab foam. It is preferable to use strong foam stabilizers, and foam stabilizers such as L580K, B4900 and B8002 can be used.

In the present invention, the ultraviolet absorber may be used alone or in combination with the ultraviolet stabilizer, and the ultraviolet stabilizer may use a Halz-based stabilizer which is a radical scavenger. Halus-based UV stabilizers include S-1190, S-2920, S-6220, S-7700, S-7830, S-7910, and S-9440.

In addition, phenolic antioxidants may be used alone or in combination with secondary antioxidants, that is, phosphorus antioxidants or styrene ester antioxidants, and secondary antioxidants are S-1680, S-6180, which are phosphorus antioxidants. S-6260, S-6280, TPP, TDP, DPDP, EHDPP, DHOP, etc. Thioester-based antioxidants include S-4120, DSTDP, DLTDP, DTDTP.

The method for producing a yolk yellow foam according to the present invention is a foamed mixture of an aromatic pre-mixed resin containing a polyether polyol having an OH functional group of 3 to 6 and a molecular weight of 3,000 to 6,000, an amine catalyst and 0.01 to 5.0 parts by weight of a metal catalyst with an aromatic isocyanate. The aromatic isocyanate may be used toluene diisocyanate or the like, and preferably, TDI-80 having 80% of 2,4 isomer content having excellent molding stability and reactivity may be used. In a preferred embodiment of the present invention, the yolk yellow foam has an index index of isocyanate of 85 to 120 is preferred, and most preferably the index index of 90 showed the best results.

In the present invention, foaming agents used in the production of foams include water, hydrochlorinated fluorocarbons (hereinafter referred to as HCFC), cyclopentane, methylene chloride, etc. The blowing agents may be used alone or in a mixture of two or more. The amount used as the blowing agent is preferably 0.1 to 5 parts by weight with respect to 100 parts by weight of polyol in the case of water, and other blowing agents are used in an amount of about 1 to 20 parts by weight.

In the practice of the present invention, in order to prevent discoloration of the foam, the antioxidant is preferably used in the range of 1 to 10 parts by weight together with the sunscreen, and a common antioxidant can be purchased commercially. For example, PUR68, I1135, I5057 series of Ciba Special, and S-1135, S-1076, S-2450, and S-4150 series of Songwon Industries can be used.

In an aspect, the present invention provides a polyether polyol having an OH functional group having a OH functional group of 3 to 6 and a molecular weight of 3,000 to 6,000; Ultraviolet stabilizers; Foam stabilizers; And a resin premix including the catalyst system is mixed and foamed with the aromatic isocyanate.

The present invention, in one aspect, 100 parts by weight of a polyether polyol having a OH functional group of 3 to 6 OH functional group, molecular weight of 3,000 to 6,000, UV stabilizer 0.3 to 3 parts by weight, phenolic antioxidant 0.1 to 1 in one aspect 5 parts by weight, 0.1 to 10 parts by weight of foam stabilizer, and 0.01 to 5.0 parts by weight of an organic tin catalyst.

Hereinafter, the present invention will be described in detail through examples. The following examples are used to illustrate the invention, and those skilled in the art should recognize that they should not be construed as limiting the invention in any case.

The yolk-urethane polyurethane product prepared by the present invention was provided as a product having excellent molding stability and foam openness by using a high molecular weight polyol, an excellent UV stabilizer, an phenolic antioxidant, and a foam stabilizer. In addition, yellowing does not occur even when exposed to light for a long time and has excellent properties of change in foam properties at light and high temperature.

In the present invention, the description of the compound, symbol and concept used in the egg yolk system is as follows.

Polyol A: A polyol obtained by reacting a glycerine initiator with 85:15 wt% of propylene oxide and ethylene oxide. OH number: 34, average molecular weight: 4,950, viscosity: 750 cps / 25 ° C

Polyol B: A polyol obtained by reacting a glycerol initiator with 100: 0 wt% of propylene oxide and ethylene oxide. OH.value: 56, molecular weight: 3,000, viscosity: 450 cps / 25 ° C

Polyol C: A polyol obtained by reacting a glycerine initiator with propylene oxide and 93: 7 wt%. OH.value: 30, molecular weight: 5,600, viscosity: 5,000 cps / 25 ° C

Polyol D: A polyol obtained by reacting a glycerine initiator with 85:15 wt% of propylene oxide and ethylene oxide. OH.value: 26, molecular weight: 6,500, viscosity: 6,000 cps / 25 ° C

Catalyst 1: Stannous octoate (T-9)

Catalyst 2: Dibutyltin dilaulate (T-12)

Catalyst 3: 33% Triethylene diamine and dipropylene glycol

Catalyst 4: 70% Bis (N, N dimetylaminoethyl) ether and dipropylene glycol

Defoamer 1: B 4900 (GOLDSMITH)

Defoamer 2: B 8002 (GOLDSMITH)

Foam stabilizer 3: L 580 (MOMENTIVE)

Foam stabilizer 4: L560 (MOMENTIVE)

Foam Detergent 5: BYK 9001 (BYK)

Antioxidant 1 S-1135 (phenolic antioxidant)

Antioxidant 2 S-1076:

Antioxidant 3 S-2450

UV stabilizer ( HALS 1: 1: S-6220 ( SONGWON )

UV stabilizer ( HALS 2: S-7700 ( SONGWON )

UV absorber 1: S-3280 ( SONGWON )

UV absorber 2: S-3200 ( SONGWON )

(compare Example N0 . 1-8, Comparative example  A, B)

The prescription and foaming conditions for yolk bladder systems are foamed under NCO% 48 toluene diisocyane (T-80) and indexes 90-120, and the RPM agitation speed is increased from 4,000 to 5,000 during the LAB stage to control the size and uniformity of the foam cells. In the low pressure foaming facility, the desired foam cell size and uniformity were obtained by adjusting the nitrogen input amount of 100 ~ 500cc, the foaming head discharge pressure 0.5 ~ 3kg / m ³ , and the high pressure foaming machine by adjusting the foamer head size. Table 1 compares the reactivity and foam molding stability according to polyol system formulation change, cell uniformity and size, moldability and UV stability according to catalyst formulation and other additive changes.

In Nos. 1 to 8, the degree of yellowing of the foam according to the type of UV stabilizer and the change of the dosage was compared. In Comparative Example A, the foam of Company I, a competitor product, was compared under the same conditions. In Comparative Example B, the evaluation of yellowing under general foam conditions without addition of UV stabilizer was compared. The yellowing evaluation of the foam was evaluated for the stability of the foam to the ultraviolet using a QUV tester which is a rapid ultraviolet measuring device. The results of UV evaluation using QUV tester showed better discoloration stability of UV absorbers than HALS antioxidants, and the higher the dosage, the more stable the UV discoloration. In addition, compared to competitors' products, QUV-A showed better discoloration stability than UV evaluation.

( Comparative Example No . 9-16, Comparative example  A, B)

No. In 9-16, it is the experiment result which evaluated stability to the ultraviolet-ray in indoor long-term conditions more than 60 days under the same prescription conditions as Examples 1-8. In contrast to the results of the QUV test, UV discoloration of the prescription with a high dose of UV stabilizer occurred. These results indicate that the initial UV stability depends on the amount of UV stabilizer used, but as time passes, the discoloration by oxidation of UV stabilizer with amine component progresses, which may affect foam discoloration. Got. In the indoor long-term evaluation, the formulations using UV absorbers showed good discoloration stability against the UV rays compared to Hals based on the QUV test results. However, contrary to the QUV test results, indoor long-term evaluations showed less fading stability against UV rays than competing products (Comparative Example A).

( Comparative Example No .17-19, Example No . 20-23, Comparative example  A)

In Nos. 17 to 23, UV absorbers under indoor long-term evaluation conditions As a result of evaluation of stability against UV rays according to the input amount, the higher the UV absorber content, the faster yellowing occurred, and the UV absorber content showed good results under 1pt or less. In addition, the discoloration to ultraviolet light showed a tendency to decrease more when the added phenolic antioxidant was added.

( Example No . 24-32, Comparative example  A)

In Examples 24 to 32, the evaluation of the stability against UV rays was carried out when the input amount of each phenolic antioxidant was changed under a long-term indoor evaluation condition. As a result of experiment, antioxidant 3 showed better yellowing stability than ultraviolet ray 1 and yellowing stability of ultraviolet ray was increased as phenolic antioxidant content was increased. In the long-term evaluation of the antioxidant content above 1pt, it showed stable results against UV rays, and the results showed less discoloration against UV rays as the antioxidant content increased.

( Example No . 33-40, Comparative example  A)

In Examples 33 to 40, the yellowing stability evaluation experiment according to INDEX change of polyol and TDI under long-term indoor evaluation conditions showed that yellowing stability against UV was higher as the INDEX was lower than the INDEX 90-120 condition.

( Example No . 41-49, Comparative example  A)

In Examples 41 to 49, the yellowing stability evaluation experiment according to the INDEX change of TDI under the solar condition showed less stability to ultraviolet rays than the indoor evaluation. These results are due to the difference in the wavelength range of sunlight irradiating ultraviolet rays in a wide wavelength range compared to an indoor lamp which irradiates ultraviolet rays in a specific wavelength range, and thus, in order to secure yellowing stability against sunlight irradiation, UV stabilizers having different wavelength absorption regions are used. The mixed use of is believed to be more advantageous for UV discoloration stability.

( Example No . 49-56, Comparative example  A)

In Examples 49 to 56, the yellowing stability against UV light was evaluated under the preconditioning condition of adding Hals-based UV stabilizer in INDEX 90 of TDI under sunlight conditions. Experimental results showed that yellowing stability against sunlight increased as the use of Hals-based UV stabilizer increased.

Although the above embodiments have been described in detail with respect to the invention, they are described for the purpose of illustrating the invention and should not be understood in any case for the purpose of limiting the invention.

Claims (9)

In the method of producing a polyurethane foam by mixing and foaming a resin premix containing a polyether polyol, a foam stabilizer and a catalyst and an aromatic isocyanate,
The polyether polyol has an OH functional group of 3 to 6, a molecular weight of 3,000 to 6,000, the catalyst is an organic metal catalyst, and the resin premix comprises a phenolic antioxidant and a sunscreen. The method of claim 1, wherein the phenolic antioxidant is contained in 0.5 to 5 parts by weight based on 100 parts by weight of the polyol. The method of claim 1 wherein the phenolic antioxidant is a 2 equivalent phenolic antioxidant. The phenolic antioxidant according to claim 3, wherein the phenolic antioxidant is benzenepropanoic acid, 3,5-bis (1,1-dimethylethyl) -4-hydroxy-, C7-9-branched alkyl ester, octadecyl- 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, triethylene glycol-bis-3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionate At least one selected. The method of claim 1 wherein the sunscreen is selected from a UV absorber, a UV stabilizer, and combinations thereof. The method of claim 1 wherein the index of polyurethane is 85-95. It is composed of a polyether polyol and an aromatic isocyanate having an OH functional group of 3 to 6 and a molecular weight of 3,000 to 6,000, 0.1-5 parts by weight of a phenolic antioxidant, 0.1-1 part by weight of an ultraviolet absorber, based on 100 parts by weight of the polyether polyol. Egg yolk polyurethane foam comprising 0.1-2 parts by weight of a UV stabilizer. 8. The yolk yellow polyurethane foam according to claim 7, wherein the polyurethane has an index of 90. 100 parts by weight of a polyether polyol having an OH functional group of 3 to 6 and a molecular weight of 3,000 to 6,000, 0.2 to 3 parts by weight of a sunscreen agent, 0.1 to 5 parts by weight of a phenolic antioxidant, 0.1 to 10 parts by weight of a foam stabilizer, and an organic tin catalyst A resin premix, comprising 0.01 to 5.0 parts by weight.