KR20120033237A - Polyurethane degraded product, polyurethane and method of forming a polyurethane - Google Patents

Abstract

PURPOSE: A polyurethane degraded product is provided to convert primary amine in the polyurethane degraded product to secondary amine, thereby improving the compressive strength of reshaped polyurethane. CONSTITUTION: Polyurethane comprises a structure in chemical formula 1, and glycol degraded product of the polyurethane comprises a compound in chemical formula 2. In chemical formula 1 and 2, R is a functional group in chemical formula 1-a, or a functional group in chemical formula 1-b, R' is a functional group in chemical formula 1-c, n is 0-6, and X and Y is O or COO, respectively. A manufacturing method of a polyurethane degraded product comprises a step of reacting toluene diamine, which is included in the glycol degraded product of polyurethane, and/or methylene dianiline with carboxyl acid anhydride in molecule, or a compound having a hydroxyl group and a carboxyl group.

Description

POLYURETHANE DEGRADED PRODUCT, POLYURETHANE AND METHOD OF FORMING A POLYURETHANE}

The present invention relates to a process for modifying amines contained in polyols that form polyurethane.

With the growing awareness of global environmental issues such as global warming and ozone depletion, the recent research and development of waste treatment technologies, especially waste plastic recycling technologies, is rapidly progressing. As a recycling technique of waste plastics, chemical recycling, which is recycled as a raw material by chemical treatment, is useful in view of the circulating use of resources.

The glycol decomposition method is known as one of the chemical recycling techniques of polyurethane (patent document 1). The glycol decomposition method is a method in which waste polyurethane is decomposed by heating and mixing in an excess of diol to produce and recover a polyol. In this glycol decomposition method, the compound which has a primary amine with polyol compound, for example, toluenediamine (TDA), methylenedianiline (MDA), etc. which are aromatic diamines are produced | generated.

When reforming a polyurethane as a part of a polyurethane raw material from the decomposition product (polyol) obtained by the glycol decomposition method, the quantity of the primary amines in a decomposition product becomes important. Since amines, such as TDA and MDA, affect the foaming and hardening rate at the time of forming a polyurethane, it is necessary to make the quantity in a urethane raw material constant. However, the amount of amine generated when the urethane is decomposed varies depending on the waste urethane to decompose, the decomposition conditions, and the drying conditions.

Therefore, as a method for converting toluenediamine (TDA) and methylenedianiline (MDA), which are aromatic diamines in a polyurethane decomposition product, to a polyol, a method of converting an amine into a polyol by reacting an alkylene oxide with an amine in Patent Documents 2 to 3 Is shown. TDA reacts with two isocyanate groups and is converted into a compound having two secondary amino groups. According to patent document 2, it is described by making the primary amine in the decomposition mixture obtained by the glycol decomposition method react with alkylene oxide, and converting it into a polyol. For example, when reacted with toluenediamine, the resulting alcohol has two secondary amino groups and two alcoholic hydroxyl groups in the molecule. The compound formed by reaction of this TDA with the alkylene oxide is reacted with two isocyanate groups and converted into a compound having two secondary amino groups. That is, since TDA and the compound obtained by reaction with alkylene oxide also react with the same amount of isocyanate group, reaction point does not increase.

On the other hand, the decomposition products obtained by the recovered polyurethane glycol decomposition method include various recovered polyurethanes, and can be formed by mixing with an unused polyol which is a raw material of polyurethane and reacting with isocyanate to form polyurethane. However, there exists a problem of the intensity | strength fall of the produced polyol generate | occur | producing, by mixing the decomposed | disassembled material obtained by collect | recovered polyurethane glycol decomposition method.

Japanese Patent Publication (Small) 53-029359 Japanese Patent Publication No. 7-309816 Japanese Patent Publication No. 7-224141

It is an object of the present invention to convert primary amines in polyurethane degradation products to secondary amines and to improve the compressive strength of reformed polyurethanes using polyurethane degradation products.

The polyurethane of the present invention is characterized by including a structure represented by the formula (1).

로 표시되는 어느 하나의 기를 나타내고, R'은

를 나타내고, 여기서 n은 0 내지 6을 나타내고, X는 O 또는 COO기를 나타냄)Where R is

Represents any group represented by R 'is

Wherein n represents 0 to 6 and X represents O or a COO group)

In addition, the polyurethane decomposition product of the present invention is characterized by reacting amines, such as toluenediamine and / or methylenedianiline, contained in the glycol decomposition products of the polyurethane with a compound having a carboxylic anhydride and a carboxyl or hydroxyl group in the molecule. do.

According to the present invention, the reforming polyurethane using the polyurethane decomposition product when converting the primary amine in the polyurethane decomposition product into the secondary amine and re-forming the polyurethane using the polyurethane decomposition product of the present invention. Can improve the compressive strength.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1: is a schematic diagram of the refrigerator box body which consists of an outer box iron plate and an inner box resin wall which fill a rigid polyurethane foam by 4-point injection, and the foam | collected form for characteristics evaluation.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

TECHNICAL FIELD This invention relates to the polyurethane which decomposes a polyurethane by glycol and forms again using the obtained decomposition liquid.

Various glycols can be used for a polyurethane decomposition agent. For example, diethylene glycol, ethylene glycol, propylene glycol, dipropylene glycol, trimethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, polyoxyethylene glycol, polyoxypropylene Dihydric alcohols such as glycol, trihydric alcohols such as 1,2,6-hexanetriol and glycerin, and polymers such as polyethylene glycol.

The amount of the disintegrating agent used for the decomposition of the polyurethane only needs to be able to liquefy the polyurethane, and 30 to 200% can be used with respect to the weight of the polyurethane. When there is much quantity of the disintegrating agent to be used, the quantity of the polyurethane decomposition product in the polyurethane to be reformed will become small. In addition, when the amount of the decomposing agent is small, the polyurethane cannot be sufficiently decomposed into the liquid.

At the time of glycol decomposition of a polyurethane, primary amines, such as toluenediamine (TDA) and methylenedianiline (MDA), are produced | generated by hydrolysis by water contained in the glycol of a polyurethane and a decomposition agent, or thermal decomposition. The polyurethane decomposition product of the present invention is characterized by reacting primary amines, such as TDA and / or MDA, contained in the glycol degradation product of polyurethane with a compound having a carboxyl group or hydroxyl group and carboxylic anhydride in the molecule. Amines such as TDA produce a compound represented by the formula (2) by reacting with a compound having a carboxyl group and a carboxylic anhydride in the molecule, for example trimellitic anhydride. The compound represented by the formula (2) has three carboxyl groups in the molecule, and there are more portions reacting with the isocyanate than TDA. Likewise, amines such as MDA produce a compound represented by the formula (2) by reacting with a compound having a carboxyl group and a carboxylic anhydride in the molecule, for example trimellitic anhydride.

로 표시되는 어느 하나의 기를 나타내고, R'은

를 나타내고, 여기서 n은 0 내지 6을 나타내고, X는 OH기 또는 COOH기를 나타냄)Where R is

Represents any group represented by R 'is

Wherein n represents 0 to 6 and X represents an OH group or a COOH group)

The compound represented by the formula (2) has three carboxyl groups in the molecule, and there are more portions reacting with the isocyanate than toluenediamine. By increasing the portion reacting with the isocyanate, it is possible to increase the compressive strength of the polyurethane formed.

The carboxylic anhydride having a carboxyl group to be reacted with the amines in the decomposition solution may be a compound having a carboxyl group and an acid anhydride in a molecule, and for example, trimellitic anhydride can be used. In the case of trimellitic anhydride, although the melting point is a solid having a melting point of 160 ° C. or higher, it is soluble in glycol which is a decomposition agent, for example, diethylene glycol, so that it can be dissolved in the decomposition solution and reacted with amines in the decomposition solution.

When reacting the compound which has a primary amine, a carboxyl group, or a hydroxyl group and a carboxylic anhydride in a decomposition liquid, 100 degreeC or less is preferable. If the reaction temperature is high, alcohol and acid anhydride, which are condensation of carboxyl group and amino group or decomposition agent of polyurethane, will react. Moreover, when reaction temperature is low, amines and acid anhydride will not fully react, and sufficient effect cannot be expected.

The amount of reacting the primary amines in the decomposition solution with the carboxylic anhydride having a carboxyl group or a hydroxyl group is preferably the same amount as the primary amino group contained in the polyurethane decomposition solution, but when an acid anhydride having a carboxyl group is added excessively, The reaction with the secondary amine or the amine catalyst used for reforming the polyurethane is predicted and is not preferable, but the carboxyl group is used even when an excessively carboxylic anhydride compound having a carboxyl group is added to the decomposition solution. And acid anhydrides readily react with isocyanates added during polyurethane reforming to form resins.

The amount of the primary amines in the decomposition solution can be controlled by the amount of the carboxylic anhydride having a carboxyl group or a hydroxyl group added to the decomposition solution, but the amount of the carboxylic anhydride having a carboxyl group or a hydroxyl group added to the decomposition solution is decomposed. Even in the case where the amount of the primary amine is excessively added, the temperature of the solution is raised after the reaction with the amine, and the acid anhydride is reacted with a secondary amine or a hydroxyl group to be consumed, followed by primary amines such as TDA and MDA. By adding, the amount of primary amine in the polyurethane raw material can be controlled.

When reforming a polyurethane using a decomposition solution, the decomposition solution obtained by reacting a primary amine such as TDA with a compound having a carboxyl group or a hydroxyl group and a carboxylic anhydride in the molecule, for example trimellitic anhydride, By reacting with an isocyanate, a polyurethane having a structure represented by the formula (1) can be formed.

<Formula 1>

로 표시되는 어느 하나의 기를 나타내고, R'은

를 나타내고, 여기서 n은 0 내지 6을 나타내고, X는 O 또는 COO기를 나타냄)Where R is

Represents any group represented by R 'is

Wherein n represents 0 to 6 and X represents O or a COO group)

At this time, the decomposition products may be mixed with polyols other than the decomposition products at any ratio to react with the isocyanate.

The polyols other than the decomposition products that can be used are not particularly limited as long as they are compounds having two or more hydroxyl groups in the molecule. For example, polyfunctional alcohols, such as ethylene glycol, diethylene glycol, triethylene glycol, trimethylene glycol, 1, 3- butylene glycol, tetramethylene glycol, glycerin, sorbitol, sucrose, bisphenol A, can be used.

Polyurethane reformed by using a decomposition solution obtained by reacting a primary amine in a decomposition solution with a carboxylic anhydride having a carboxyl group or a hydroxyl group has a compressive strength as compared with a polyurethane that is formed without removing the amines in the decomposition solution. Is high. This is an effect by which the crosslinking point increased by making acid anhydride which has a carboxyl group, and amine react.

The present invention is effective even when an amine is used for part or all of the polyurethane disintegrator. When an amine compound is included in a decomposition agent, the acid anhydride which has a carboxyl group may also react with the amine compound contained in a decomposition agent, and may increase the part which an amine compound reacts with an isocyanate.

[Example]

Hereinafter, embodiments of the present invention will be described.

Example 1

Hereinafter, about the sample 1, the manufacturing method and the measuring method of a physical property value are demonstrated.

30 g of diethylene glycol was added to 30 g of the polyurethane fractionated and collected from the waste refrigerator, and heated at 180 ° C. and stirred for 5 hours to obtain 60 g of a glycol decomposition solution of polyurethane. 1.5 wt% of 4,4-methylenedianiline was contained in the decomposition liquid obtained by analysis by GC. The obtained polyurethane decomposition solution was filtered, 1.2 g of trimellitic anhydride was added, and it stirred at 80 degreeC for 30 minutes. The obtained solution confirmed the production of the compound of formula 3 by liquid chromatography mass spectrometry (LC-MS).

로 표시되는 기를 나타냄)Where R is

Represents a group represented by)

Subsequently, 10 weight% of polyurethane decomposition solutions were added to the polyol which mixed an appropriate amount of tolylene diamine polyether polyol, triethanolamine polyether polyol, bisphenol A polyether, etc. to make 200 g, and it was cyclopentane as a foaming agent. And a silicone foam stabilizer and a catalyst were used as the polyol premixed liquid in which water was mixed with an auxiliary blowing agent in an appropriate amount. Polymethylene polyphenyl diisocyanate (MDI) type isocyanate was added to the polyol premix liquid, and it filled in the refrigerator box body which consists of an outer box iron plate and an inner box resin wall shown in FIG. 1 by the high pressure foaming machine, and obtained the heat insulation box body. At that time, 110% of the liquid mixture was heated and foamed at 40 degreeC with respect to the amount of polyurethane foam at the time of free foaming. The schematic diagram of the refrigerator box body which consists of an outer box iron plate and an inner box resin wall which filled a rigid polyurethane foam by four point injection in FIG. 1, and the foam sample collected for the characteristic evaluation are shown.

The compressive strength of the formed polyurethane was 10% deformation by loading a 50 mm × 50 mm × 35 (t) mm foam at a feed rate of 5 mm / min from the urethane-filled insulation part at least 500 mm away from the urethane inlet. It measured at the stress in time.

The production method of Samples 2 to 5 is as follows.

Sample 2: Using the amount of 1/2 the amount of trimellitic anhydride used in Sample 1, the polyurethane decomposition solution was treated in trimellitic anhydride in the same manner as in Sample 1, and the polyurethane was Was reformed to obtain Sample 2.

Sample 3: Using a double amount of trimellitic anhydride used in Sample 1, the polyurethane decomposition solution was treated in trimellitic anhydride in the same manner as in Sample 1, and the polyurethane was re-used by the same method as in Sample 1. It formed and the sample 3 was obtained.

Sample 4: After forming a polyurethane decomposition product by the same method as Sample 1, when trimellitic anhydride is added and heated to a polyurethane decomposition product, it heats at 120 degreeC, and reprocesses a polyurethane by the same method as Sample 1. It formed and the sample 4 was obtained.

Sample 5: A polyurethane decomposition product was formed in the same manner as in Sample 1, trimellitic anhydride was added to the polyurethane decomposition product, followed by heating, followed by tolylene diamine polyether polyol, triethanolamine polyether polyol, and bisphenol A system. 20 weight% of polyurethane decomposition solutions were added to the polyol which mixed a suitable amount of polyether, etc., and polyurethane was reformed by the method similar to the sample 1, and the sample 5 was obtained.

Comparative Example 1

Hereinafter, the manufacturing method and the measuring method of a physical property value about Samples 6 and 7 are demonstrated.

Sample 6: The polyurethane decomposition product was formed by the same method as in Example 1, and then polyurethane was reformed by the same method as in Example 1 without addition of trimellitic anhydride.

Sample 7: After forming a polyurethane decomposition product by the same method as Example 1, when trimellitic anhydride is added and heated to a polyurethane decomposition product, it heats at 180 degreeC, and is a polyurethane by the method similar to Example 1 Was reformed.

Comparing the compressive stress of the polyurethanes formed using Samples 1 to 7, in any of Samples 1 to 5 of Example 1, the treatment with trimellitic anhydride shown in Sample 6 of Comparative Example 1 was not performed. It was high compressive stress compared with the polyurethane formed using the decomposition liquid. In addition, in any of the samples of Example 1 formed by using a decomposition solution subjected to treatment with trimellitic anhydride at 120 ° C and 80 ° C, the trimellitic anhydride at 180 ° C shown in Sample 7 of Comparative Example 1 It was high compressive stress compared with the polyurethane formed using the decomposition liquid which processed.

The polyurethane of the present invention can be applied to, for example, a heat insulator for a refrigerator, and is suitable for recycling use of the polyurethane for a refrigerator.

1 urethane injection head
2 urethane inlets
3 thermal insulation box
4 outer box griddle
5 inner box resin wall
6 Characteristic evaluation sampling position

Claims (5)

Polyurethane comprising a structure represented by the formula (1).
<Formula 1>

Where R is

Represents any group represented by R 'is

Wherein n represents 0 to 6 and X represents O or a COO group) Glycolyte decomposition products of the polyurethane comprising the compound represented by Formula (2).
<Formula 2>

Where R is

Represents any group represented by R 'is

Wherein n represents 0 to 6 and X represents an OH group or a COOH group) A polyurethane degradation product characterized by reacting toluenediamine and / or methylenedianiline contained in a glycol decomposition product of polyurethane with a compound having a carboxylic anhydride or a hydroxyl group and a carboxyl group in a molecule. Polyurethane formed using the decomposition product obtained in claim 3. The polyurethane insulation of Claim 4 was used. The heat insulating material for refrigerators characterized by the above-mentioned.

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