JPS60127318A - Reactive antioxidant composition - Google Patents

Abstract

PURPOSE:To provide titled composition capable of increasing resistance to oxidative deterioration by its bonding to polymer sensitive to such deterioration, consisting mainly of a compound of specific formula obtained by the reaction between isophorone diisocyanate and phenolic compound of specified formula. CONSTITUTION:The objective composition consisting mainly of a compound of formula II (A is isophorone diisocyanate residue; B is phenolic compound residue; n is 0-3), which can be obtained by dissolving in a solvent (e.g. N,N- dimethyl acetamide). (A) isophorone diisocyanate and (B) a phenolic compound of formula I (R1 is t-butyl, sec-butyl or neopentyl) [e.g., 1,3,5-tris(4-t-butyl-3-hydroxy- 2,6-dimethylbenzyl)isocyanuric acid] followed by reaction.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to antioxidant compositions having active groups that can be attached to polymers. More specifically, the present invention relates to an antioxidant composition that can be bonded to polyurethane, which is subject to severe oxidative deterioration due to sunlight, heat, etc., and can prevent the oxidative deterioration thereof.

Polyurethane obtained from polyin 7anate, a relatively low molecular weight polymer diol, and a low molecular weight polyfunctional active hydrogen compound has excellent mechanical properties and is easy to process, so it can be used in foams, elastomers, paints, synthetic leather, fibers, etc. However, the use of antioxidants is essential to prevent deterioration during processing and to impart durability. Generally, phenolic antioxidants are used as antioxidants for polyurethane due to their excellent effects. Antioxidants are used, especially phenolic compounds represented by the following general formula (wherein Ro represents a group selected from t-butyl, 1lee-butyl, and neopentyl), which are used to protect against combustion gas, chlorine, It is a preferable antioxidant because it does not cause side effects such as discoloration due to sunlight. However, when this phenolic compound is blended into polyurethane for textiles, tapes, and artificial leather for clothing, it can be used during processing steps such as scouring, bleaching, dyeing, and heat treatment leading to the final product, as well as during home washing and dry cleaning during the use stage. There is a problem that antioxidants leak out from the product and lose their antioxidant effect.

One possible way to eliminate the leakage of antioxidants from products is to bond them to polymer chains. For example, in the general method of synthesizing polyurethane by obtaining a prepolymer with an NGO group at the end from diisocyanate and diol, and then chain-extending this prepolymer solution with a chain extender, After polymer synthesis or during chain extension, a phenolic compound as an antioxidant is allowed to coexist to reduce NCO at one end of the prepolymer.
A method of bonding the stabilizer to the polymer by reacting the 0H group of the phenolic compound with the group may be considered. However, in the case of the phenolic compound represented by the general formula, which has excellent antioxidant effects and has no side effects, crosslinking reactions are difficult to avoid because it has three OH groups that can react with NGO groups, as is clear from the molecular structure. If the reaction is carried out in a solution, the polymer solution (dope) will gel, making it impossible to obtain a dope that can be used for molding.

The present inventors have discovered that it can be bonded to polyurethane without gelation, has excellent antioxidant effects,
As a result of extensive research on antioxidants that do not cause side effects, we have found that a reaction composition of a specific diisocyanate and a specific trifunctional phenol compound has an excellent antioxidant effect and can be easily treated without causing gelation. It has been discovered that it is possible to bind polyurethane molecule #I to polyurethane molecule #I, leading to the completion of the present invention.

That is, the present invention provides a composition containing as a main component a compound represented by the general formula ■ obtained from inphorone diisocyanate and a phenolic compound represented by the following general formula (I) (wherein R□ is t).
-A-NHCO40-B-00CH (representing a group selected from -butyl group, Bee-butyl group and neopentyl group)
N-A-NHCO 0-B @ (wherein, A represents the residue of inphorone diincyanate, and B represents the residue of the phenolic compound of general formula (1). n is in the range of 0 to 3. ) The reactive antioxidant composition of the present invention is obtained by reacting inphorone diisocyanate with a phenolic compound (hereinafter abbreviated as phenolic compound) represented by the general formula (I>). Examples of the phenolic compounds represented include 1,3,5-)lis(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanur 112.1,3,5-tris(4- 5ee
-butyl-3-hydroxy-2,6-dimethylpenzyl)incyanuric acid, 1,3.5-)LX (4-neopentyl-3-hydroxy-2,6-dimethylbenzyl)
Examples include incyanuric acid. Particularly preferred from the viewpoint of production and effectiveness is 1,3.5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)incyanuric acid.

The reaction is preferably carried out in a solvent that is inert to inphorone diisocyanate and the phenolic compound and that dissolves the reaction composition. Preferred solvents include N,N-dimethylacetamide, N,N-diethylacetamide,
Examples include amide polar organic solvents such as N-methyl-2-pyrrolidone. In order to avoid a heterogeneous reaction, the phenolic compound is first dissolved in a solvent, and then inphorone diisocyanate is added thereto at once and reacted with stirring. If the temperature during the reaction is too low, the reaction will take too long, and if it is too high, all three OH groups of the phenolic compound will have reacted, and therefore compounds with no antioxidant effect will be likely to be produced. The temperature range is preferably from 30°C to 90°C, more preferably from 30°C to 70'C.

The reaction ratio line of isophorone diisocyanate and hexaphenolic compound shows that as the ratio of inphorone diisocyanate increases, unreacted inphorone diisocyanate tends to remain, and compounds in which 2 or more OH groups of phenolic compounds have reacted are generated. This is undesirable since it increases the viscosity of the dope upon bonding to poly-V-, and the antioxidant effect is also poor.

Conversely, when the proportion of phenolic compounds increases, the production of compounds with an antioxidant effect that have NCO groups at their ends and can be bonded to polymers decreases, and unreacted 3
This is not preferable because the phenolic compound having an OH group tends to remain undesirably and therefore causes gelation when bonded to the polymer.

Usually the molar ratio (number of moles of phenolic compound/mole a of inphorone diisocyanate) is 1. It is preferable to carry out the reaction at a temperature of 0 to 2.0 degrees, preferably 1.0 to 1.5 degrees.

The antioxidant composition of the present invention can be bonded to a polymer, and is characterized in that it has an NCO group as a reactive group to be bonded.

Total NC of inphorone diisocyanate containing NCO group
Reactants remaining in an amount of 50 equivalents or more relative to the O group equivalent contain a large amount of unreacted inphorone diisocyanate, and therefore significantly increase the viscosity of the dope upon bonding to the polymer, and may also cause the target compound to The amount of isophorone diincyanate produced is low, and a large amount is required to bind it to the polymer and exhibit its antioxidant effect, which is undesirable.On the other hand, if the amount of residual NCO groups is small, there is almost no unreacted isophorone diincyanate. Although it can be bonded to a polymer without causing thickening or the like, it is not preferable because the amount of the target component that can be bonded to the polymer is small. The optimum amount varies depending on the charging ratio and reaction temperature, but 10 equivalents to 50 equivalents, more preferably 15 equivalents to 45 equivalents of NCO groups remain based on the total NCO group equivalents of the charged inholo/diisocyanate. A reaction composition.

In order to obtain a reaction composition with a desired amount of residual NCO groups, the concentration of residual NCO groups in the reaction system is analyzed by a known method, and the remaining NG
When the amount of O groups reaches the desired amount of NCO groups, heating is stopped to stop the progress of the reaction. In order to prevent the reaction from progressing during storage, it is preferable to keep the reaction composition as low as possible, usually below aO 0 C, preferably below 15°C when stored for a long period of time.

It is preferable to avoid introducing moisture into the reaction system as much as possible, to sufficiently dry and dehydrate the raw materials in advance, and to carry out the reaction under a nitrogen blanket. It is also preferable to keep it sealed with nitrogen during storage.

The reactive antioxidant composition of the present invention is A-NHCO+ 0-B -00CHN-A-NHCO
The main component is a compound represented by the general formula 0-B. In the formula, A is a residue of inholo/diisocyanate, B is a residue of a phenolic compound represented by the general formula (D), and n
is in the range of O#3.

(In the formula, R11t represents a group selected from t-butyl group, 5ee-butyl group, and neopentyl group) Generally, when a bifunctional compound (denoted as X) and a trifunctional compound (denoted as Y) are reacted , the one-to-one reaction product of X and Y, that is, X-Y, and the reacted X-Y-X-Y, X-Y-X-
Although it is almost impossible to efficiently synthesize Y-X-Y etc.4, surprisingly, in the case of the reaction between the specific diisocyanate of the present invention and the above-mentioned specific phenol compound,
Despite the reaction between bifunctional and trifunctional compounds,
A one-to-one reactant xy (corresponding to n=0 in the compound represented by the general formula (1) of the present invention) is produced extremely efficiently. The reaction further progresses to produce compounds X-Y -X-Y (corresponding to n=1) and X-Y -X-Y -X-Y (corresponding to n-2), but these compounds are not bonded to the polymer. It also has an 0H group directly connected to the benzene nucleus, which is necessary for exhibiting the antioxidant effect, so it maintains the antioxidant effect and can achieve the purpose of the present invention. It is a compound. The reactive antioxidant of the present invention is A-NHCO (-0-B-00CHN-A-NH
It is represented by the general formula CO 0-B, where n is a compound in the range of 0 to 3. A compound with a large n, that is, a high molecular weight, is not preferable because, when bonded to a polymer, the mechanical properties and heat resistance of the polymer deteriorate. Compounds with a low n value are preferred because they have less adverse effect on other properties. Particularly preferred is a reaction composition in which the compound represented by the general formula in which n is 0 accounts for 50% by weight or more of the total weight.

In order to obtain a reaction composition containing a large amount of compounds with low n, the reaction temperature should be lowered and a mild reaction method should be used without using a tin-based or tertiary amine-based catalyst used for the reaction between NCO groups and O■I groups. Preferably, the reaction is carried out under conditions.

The remaining unreacted phenolic compound and isophorone diisocyanate must be kept to a minimum, as the former causes the dope to gel, and the latter causes the dope to thicken. A dope suitable for molding can be obtained if it is less than or equal to . Confirmation of whether the target compound is produced can be performed by a known method such as GPC or liquid chromatography.

Since the reactive antioxidant composition of the present invention obtained in this way has a reactive NCO group at the end, it can be bonded to any polymer having active hydrogen, but it is particularly susceptible to oxidative degradation. It is useful for bonding to polyurethanes with strong oxidative properties and imparting resistance to oxidative degradation to polyurethanes.

Various bonding methods can be considered depending on the polymer and whether it is carried out during polymer production or after molding. Examples of polyurethane are shown below, but this does not limit the usefulness of the reactive antioxidant composition of the present invention. Generally, polyurethane used for dry molding and wet molding is produced by reacting excess diisocyanate and diol to synthesize a prepolymer with NGO groups at the end, and then dissolving this prepolymer in a solvent. It is synthesized by chain-extending the prepolymer by adding an amine solution consisting of a monoamine as a modifier, but when bonding during polyurethane synthesis, the second method is to add an amine solution consisting of a monoamine as a modifier to the diamine in advance. Adding the inventive NC0 group-terminated reaction composition to prepare a diamine solution containing the monoamine to which the reaction composition is attached, and if necessary adding another monoamine such as diethylamine as a molecular weight modifier, The prepolymer is chain-extended with this amine solution, and the antioxidant composition of the present invention is bonded to the polymer terminals. Another method is to synthesize an NH, group-terminated polymer by carrying out chain extension with an excess equivalent of amine based on the NCO groups possessed by the prepolymer;
The NCO group-terminated reaction composition of the present invention is added to this polymer solution to bind the antioxidant composition of the present invention to the polymer terminals. If done after molding, use fibers or sheets.

After molding into a film or the like, the molded product is treated with the antioxidant composition solution of the present invention to bond to the terminal NH, group, -NHCOO- bond, -NHCONH- bond, etc. of the polyurethane on the surface of the molded product, 1 If necessary, known stabilizers, pigments, dyes, extenders, etc. may be added to the polymer bound with the reactive antioxidant composition of the present invention.

The reactive antioxidant composition of the present invention has an excellent antioxidant effect without side effects such as yellowing, and furthermore, since it has a reactive group, it can be bonded to a polymer, so it can be bonded to a polymer using conventional methods. Since there is no leakage of the antioxidant during the processing process or during the use of the product, unlike in the case of simple compounding, its excellent antioxidant effect remains unchanged even when subjected to various treatments. In addition, since the antioxidant does not leak out, a sufficient effect can be achieved by adding a small amount. Therefore, since antioxidants are generally expensive, it is economically advantageous to be able to reduce the amount of antioxidant used. be. Furthermore, the antioxidant composition of the present invention having excellent antioxidant effects has the characteristic that it can be synthesized extremely efficiently.

Since the reactive antioxidant composition of the present invention has a reactive NCO group, it can be bonded to a polymer having active hydrogen to maintain a certain level of oxidative deterioration resistance over a long period of time even after treatment. It is useful to have the It is particularly used in a wide range of applications, and is useful for imparting durability against oxidative deterioration by bonding to polyurethane, which is susceptible to oxidative deterioration.

EXAMPLES The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to the scope of these Examples.

#, The measurement of the characteristic values in the examples is as follows: Light embrittlement resistance test Each sample (fiber-like or film-like) was irradiated with ultraviolet rays using a fade meter (manufactured by Suga Test Instruments Co., Ltd.), and then the breaking strength was measured using a Tensilon tester. The strength retention rate ((breaking strength of sample after irradiation/breaking strength of sample before irradiation))
10G).

Heat resistance test Cylindrical metal surface VC100qIl with surface temperature of 180℃
Each stretched sample was brought into contact and the time until the sample was cut was measured.

Gas discoloration test Propane combustion gas was introduced into a chamber with a volume of about 0.03-cm, and each sample was exposed for a certain period of time while maintaining the room temperature at 60° C., and the degree of discoloration was visually judged according to the following criteria.

○: No difference from unexposed sample Δ: Difference in discoloration compared to unexposed sample ×: Large degree of discoloration Analysis of reaction composition (1) Measurement of remaining NGO group amount A fixed amount of the reaction solution was added to n-butylamine chloride. It was added to the benzene solution, and the remaining amine was neutralized and titrated with a normal hydrochloric acid solution.

(2) Composition analysis high performance liquid chromatograph (manufactured by Waters, U6Kf
In i), the reaction composition was analyzed using chlorotetraform as a solvent. The molecular weight of Tao 1 is the molecular weight in terms of polystyrene.

Example 1 Thoroughly dehydrated N,N-dimethylacetamide 1000f
and dried powdered 1.3.5-)lis(4-t-butyl-3-hydroxy-2,6-dimethylbe/dirunisocyanuric acid asof (o, s mol)) were charged into a reaction vessel. After the dissolution is complete, add isophorone diincyanate 891 (0,4 mol) in one portion and add 5 ml under stirring.
The reaction was started at 0°C. After 40 hours, the mixture was cooled to stop the reaction. Residual NCO group equivalent of the obtained reaction product ((Remaining NCO group equivalent/NCO group equivalent at the time of preparation) x l
oo) was 41.3%. Additionally, as a result of GPC analysis, the reaction product contained approximately 75% by weight of 1:1 reaction products, and several weight% of unreacted phenolic compounds remained, but unreacted inphorone diisocyanate Most were not included. The high molecular weight substance having a molecular weight of around 3700 was slightly depressed.

Example 2 An example of bonding the reaction composition obtained in Example 1 to polyurethane is shown.

Litetramethylene/ether glycol 200f with a molecular weight of 200A and 4,4'-diphenylmethane diisocyanate
) 50f was reacted at 70° C. for 1.5 hours to obtain a prepolymer having incyanate groups at both ends.

To this, 500 f of N,N-dimethylacetamide was added and dissolved to make a homogeneous solution.

On the other hand, a solution of 6f of ethylenediamine and 40t of N,N-dimethylacetamide was cooled to 5°C, and 30f of the reaction composition bath solution obtained in Example 1 was slowly added with vigorous stirring.
An amine solution containing the reaction composition and a monoamine bound to ethylenediamine was prepared.

The amine solution was added all at once to the prepolymer solution cooled to 5° C. with vigorous stirring to carry out a chain extension reaction, thereby obtaining a polyurethane solution in which the antioxidant of the present invention was bonded to the molecular ends. This polyurethane solution does not gel,
The viscosity at 30°C was 2500 voids, which was suitable for molding.

The polyurethane solution thus obtained was cast onto a glass plate and dried at 70° C. for 3 hours to obtain a film with a thickness of about 70 μm. Some films are placed in perchloren at 50℃ for 2 hours.
The samples were immersed for a period of time and then immersed in boiling water for 4 hours.

The untreated and treated films were cut into 1-inch widths and irradiated with a fade meter for 20 hours to perform a needle base embrittlement test.

The results are shown in Table 1.

Comparative Example 1 A prepolymer solution prepared under the same conditions as Example 1 was chain-extended using an amine solution consisting of 5.7 f of ethylenediamine, 0.73 f of diethylamine as a molecular weight regulator, and 60 f of N,N-dimethylacetamide. A polyurethane solution was obtained. The viscosity of this polyurethane solution is 235
It was O poise. This solution was divided into two parts, and one solution contained the LL5- AI) Incyanuric acid was blended with polymer 1002/D1.5. No antioxidant was added to the other solutions. Films were prepared from these two types of polyurethane solutions, treated in the same manner as in Example 1, and tested for needle base embrittlement. The results are shown in Table 1.

As is clear from Table 1 below, the film obtained from the polymer solution in which the antioxidant composition of the present invention is bonded to the polymer edge has excellent light embrittlement resistance, and is more easily treated than the comparative example containing a simple antioxidant. It was found that excellent light embrittlement resistance was maintained even after exposure to irradiation.

Example 3 and Comparative Examples 2-4 Isophorone diincyanate and 1.3.5-)lith(4
-1-Butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanuric acid by changing the synthesis conditions to obtain a reaction product within the scope of the present invention (Example 3), a compound represented by the general formula <IO of the present invention Reaction composition containing a large amount of high molecular weight substance (comparative example 2) with low content and advanced reaction (comparative example 2) 1 General formula (IQ
A reaction composition (Comparative Example 31 Comparative Example 4) containing a small amount of the compound represented by and a large amount of unreacted substances was obtained. Table 2 shows the synthesis conditions and the properties of the reaction composition obtained. Each reaction composition obtained was first added to an ethylenediamine solution in the same manner as in Example 1, and then a prepolymer solution prepared under the same conditions was chain-extended with the obtained amine solution. Polymer solutions that do not gel and have a viscosity suitable for molding are then formed into films.

Its light embrittlement and heat resistance were measured. These results are shown in Table 3.

As shown in Table 3 below, the polymer film (Example 3) bonded with the reaction composition of the present invention has excellent light embrittlement resistance and good heat resistance. In the case of a reaction composition containing a small amount of compounds and a large amount of high molecular weight substances (Comparative Example 2).

The amount of bonding to the polymer is small, so the light embrittlement after perchloren treatment decreases, and if the amount used is increased to increase the amount of bonding to the polymer, the light embrittlement is good even after percuren treatment, but the heat resistance decreases. In the case of reaction compositions with a large decrease in , or containing a large amount of unreacted substances (Comparative Examples 3 and 4)
It was found that gelation occurred during bonding to the polymer, making it impossible to obtain a polymer solution suitable for molding.

Example 4 and Comparative Examples 5 to 5 A polymer solution in which the antioxidant composition of the present invention obtained in Example λ was combined, and a polymer solution in which various antioxidants were blended with the polymer solution of Comparative Example 1 (comparative Examples 5-7) 4
From the hole orifice.

It was discharged into an atmosphere at 220°C, spun, dried, temporarily twisted, oiled, and wound at 300 m/min to form a 4O denier fiber.

A gas color change test was conducted on this fiber.

These results are shown in Table 4.

Table 4 From Table 4, it can be seen that the antioxidant composition of the present invention does not turn yellow even when exposed to gas.

Claims (1)

[Scope of Claims] L A composition containing as a main component a compound represented by the general formula (6) obtained from isophorone diisocyanate and a phenol compound represented by the following general formula (I) (wherein RX is a t-butyl group). , 5ee-butyl group and neopentyl group)A-N)ICO(-0-B-00CHN
-A-NHCO-)HO-B (It) (wherein A represents the residue of inholo/diisocyanate, B represents the remainder of the phenolic compound of the general formula (p), and n ranges from θ to 3. .)2 The compound represented by general formula (II) where n is 00 is 50
The composition according to claim 1 and unreacted isophorone diisocyanate and the general formula (
The composition according to claim 1, wherein the phenolic compound represented by I) is 10% by weight or less.