WO2019093729A2 - Method for preparing polyamide by anion ring-opening polymerization and polyamide prepared thereby - Google Patents

Abstract

The present invention relates to a method for preparing a polyamide by anion ring-opening polymerization and a polyamide prepared thereby and, more specifically, to a method for preparing a polyamide by anion ring-opening polymerization and a polyamide prepared thereby, wherein the method is an eco-friendly processing method not using a solvent as a catalyst and enables polymerization to a uniform molecular weight with a high conversion rate in a short polymerization reaction time at a low temperature, compared with an existing polymerization method. The method for preparing a polyamide by anion ring-opening polymerization according to the present invention to attain such a purpose is a method for preparing a polyamide by an anion polymerization reaction, wherein lactam, and relative to 100 parts by weight of the entire lactam, 0.01-20 parts by weight of an alkali metal as an initiator, 0.3-10 parts by weight of a molecular weight adjuster, and 0.002-1.0 parts by weight of carbon dioxide as an activator may be included. As described above, the present invention is directed to an eco-friendly processing method not using a solvent as a catalyst and has an effect of enabling polymerization to a uniform molecular weight with a high conversion rate in a short polymerization reaction time at a low temperature, compared with an existing polymerization method.

Description

A process for producing a polyamide by anion ring-opening polymerization and a polyamide produced by the process

The present invention relates to a process for producing polyamides by anion ring-opening polymerization and a polyamide produced by the process, and more particularly to a process for producing a polyamide by an anion ring- The present invention relates to a process for producing a polyamide by anion ring-opening polymerization which enables a high-molecular-weight polymerization with a high conversion ratio within a short period of time, and a polyamide produced thereby.

The polyamide resin is a linear polymer bonded by an amide (-NHCO-) bond and is strong and has excellent properties such as abrasion resistance, abrasion resistance, oil resistance and solvent resistance, and is easily melt-molded. , Engineering plastics, and the like. Polyamides can be classified into aliphatic polyamides, aromatic polyamides and aliphatic cyclic polyamides depending on the molecular structure. Nylon is referred to as an aliphatic polyamide, and aramid as an aromatic polyamide. do.

Such polyamides are prepared by various polymerization methods, such as by ring-opening polymerization of lactams such as nylon 6, by polycondensation of diamines and dibasic acids such as nylon 6,6, nylon 6,10 and nylon 4,6, Such as nylon 11 and nylon 12, by the polycondensation of aminocarboxylic acid. So-called hybridized nylon such as a condensation product of caprolactam and 6,10-nylon salt (hexamethylenediamine and sebacate) is industrially produced. In addition, functional groups such as a side chain and a hydroxyl group, And various types of polyamides including heterocyclic rings have been studied.

The lactam, such as caprolactam, may be anionic polymerized. This method generally uses a catalyst, and also an initiator (also referred to as an activator) (activated anion polymerization). Until now, frequently used initiators or activators have included diisocyanates or derivatives thereof.

US 4,754,000 (Bayer AG) describes the activated anion polymerization of lactams to prepare polyamides using a polyisocyanate containing a biuret group and derived from a non-aromatic diisocyanate as an activator.

EP 1091991 (BASF AG) discloses compositions comprising as component A polyisocyanurate having an average of more than 3.5 NCO functional groups, and also a method of making a surface coating composition using the compositions described.

US 3423372 uses a non-capped polyisocyanate (thus significantly reducing reactivity) and the concentration of activator in that example is very low (1/200 to 1/50 moles). Polymerization takes more than three minutes for the concentration used in this US patent.

EP 0156129 uses rubber (i.e., an elastomer) as a precursor of a multifunctional activator, and thus the resulting PA is not as hard as a maximum of 1.12 GPa. The active agent has a high Mw, wherein a large amount of activator is required (20% or more). A mixture of a bifunctional activator and a multifunctional activator is used; Thus, the resulting polyamide is not a crosslinked material.

U.S. Patent No. 4,067,861 (1978) discloses an anionic polymerization technique of lactam through an extruder in which a metering pump is provided between an extruder body and an extruder die to obtain a constant output, uniform viscosity, (metering pump) was installed to solve the viscosity non-uniformity mechanically, but it is not a fundamental solution.

U.S. Pat. No. 3,878,173 (1975) points out the problem of unstable viscosity due to pyrolysis and the formation of a structurally disorderly branching structure, but in order to prevent the decomposition of the synthesized polymer, a more acidic additive There is no mention of uneven branching structure solving. For reference, the branching side reactions that occur during polyamide anionic polymerization are described in MP Stevens, 'Polymer Chemistry', 2nd ed., Oxford University Press, p 429 (1990) and G. Odian, 'Principles of Polymerization', 2nd Ed., John Wiley & Sons, p541 (1981).

In particular, U.S. Patent 5,747,634 (1998) introduces a solution liquid system that simultaneously contains a catalyst and an initiator (reaction promoter) to obtain a more uniform product. Here, a solution system is introduced to obtain a uniform product having a uniform quality and a reproducible result is described. However, there is a problem in that it is not efficient due to a solvent removal problem in applying to the reaction extrusion method.

[Prior Art Literature]

[Patent Literature]

(Patent Document 1) US 2016-0102175

(Patent Document 2) US 5,519,097

(Patent Document 3) US 3,883,608

(Patent Document 4) US 7,135,428

(Patent Document 5) US 5,362,448

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art and the technical problems required from the past.

It is an object of the present invention to provide an eco-friendly process which does not use a solvent as a catalyst and which is capable of polymerizing at a low molecular weight with a high conversion ratio at a low temperature within a short polymerization time, And a polyamide produced by the method.

In order to accomplish the above object, the present invention provides a process for producing polyamide by anion polymerization, which process comprises reacting 100 parts by weight of lactam and the lactam in an amount of 0.01 to 20 parts by weight of an alkali metal as an initiator, 0.3 to 10 parts by weight of a molecular weight modifier, and 0.002 to 1.0 part by weight of carbon dioxide as an activator.

In one preferred embodiment of the present invention, the lactam is at least one selected from the group consisting of caprolactam, laurolactam, pyrrolidone and piperidinone. And a manufacturing method thereof.

More specifically, in one preferred embodiment of the present invention, the lactam is composed of two kinds, and at least one lactam is contained in an amount of not less than 50 parts by weight based on 100 parts by weight of the total lactam. A process for preparing polyamide by polymerization is provided.

According to the present invention, by using carbon dioxide as an activator without using a solvent as a catalyst, it is possible to produce a polyamide having a polydispersity index (PDI) having a narrow molecular weight distribution through an appropriate amount of a molecular weight modifier during polymerization.

In one preferred embodiment of the present invention, the alkali metal may include at least one selected from the group consisting of a metal hydride, a metal hydroxide, and a metal alkoxide, , But is not limited thereto.

In one preferred embodiment of the present invention, the molecular weight modifier is selected from the group consisting of ethylene-bis-stearamide (EBS), amine compounds, urea compounds and di- And at least one compound selected from the group consisting of compounds.

In one preferred example according to the present invention, the polymerization reaction may be carried out at a temperature range of 180 to 250 ° C for 0.5 to 120 minutes based on the laboratory reactor. Here, the polymerization reaction time is not particularly limited and may be appropriately adjusted depending on the weight of the compound to be charged or the size and type of the reactor.

In one preferred example according to the present invention, the lactam in the polymerization reaction may have a conversion of at least 95% to polyamide.

On the other hand, the present invention provides a polyamide produced by the above polyamide production method.

In one preferred example according to the present invention, the polyamide may have a molecular weight distribution value of 3.0 or less.

In one preferred embodiment of the present invention, the weight average molecular weight (Mw) of the polyamide may range from 40,000 to less than 80,000.

In one preferred example according to the invention, the polyamide may be a linear, branched, polybranched having a hyperbranched or dendritic structure.

On the other hand, the present invention relates to a polyamide resin composition for a vehicle, a material for an electronic device, an industrial pipe material, an architectural civil engineering material, a 3D printer material, a fiber material, a cladding material, It provides parts materials selected from the group consisting of materials for aviation, materials for solar cells, materials for batteries, materials for sports, materials for home appliances, household materials and cosmetics.

In a specific example, the product comprising the component material is selected from the group consisting of automotive air ducts, plastic / rubber compounds, adhesives, lights, polymer optical fibers, fuel filter caps, line systems, cables of electronics, reflectors, Wire protection tube, control unit, light tube, pipe tube, liner, pipe coating agent, oilfield hose, 3D printer, multifilament, spray hose, valve, duct, pulp, gear, medical catheter, aircraft fire retardant, , High hardness film, ski boots, headset, eyeglass frame, toothbrush, water bottle or outsole.

As described above, the present invention is an eco-friendly process which does not use a solvent as a catalyst, and has a high conversion ratio at a low temperature in a short polymerization time and can produce a polymer having a uniform molecular weight.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a graph showing the results of GPC analysis of polymerized samples prepared according to the present invention;

2 is a graph showing the results of DSC analysis of the polymerization samples prepared according to the present invention;

3 is a graph showing the results of TGA analysis of the polymerization samples prepared according to the present invention.

The following description of the invention refers to specific embodiments in which the invention may be practiced by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that the various embodiments of the present invention are different, but need not be mutually exclusive. For example, certain features, structures, and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the invention in connection with one embodiment.

The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is to be limited only by the appended claims, along with the full scope of equivalents to which such claims are entitled, if properly explained.

Further, unless otherwise specified, "substituted" to "substituted" means that at least one hydrogen atom of the functional group of the present invention is substituted with a halogen atom (-F, -Cl, -Br or -I) A nitro group, a cyano group, an amino group, an amidino group, a hydrazine group, a hydrazone group, a carboxyl group, an ester group, a ketone group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alicyclic hydrocarbon group, , A substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted heteroaryl group, and a substituted or unsubstituted heterocyclic group, , The substituents may be connected to each other to form a ring.

In the present invention, the term "substituted" as used herein means an aryl group substituted with a substituent such as a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, .

The above-mentioned "hydrocarbon group" means a linear, branched or cyclic saturated or unsaturated hydrocarbon group unless otherwise specified, and the alkyl group, alkenyl group, alkynyl group and the like may be linear, branched or cyclic.

Further, unless otherwise specified in the present specification, "alkyl group" means C1 to C30 alkyl group, and "aryl group" means C6 to C30 aryl group. In the present specification, the "heterocyclic group" refers to a group containing 1 to 3 hetero atoms selected from the group consisting of O, S, N, P, Si and combinations thereof in one ring. Examples thereof include pyridine, Thiophene, pyrazine, and the like, but is not limited thereto.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings in order to facilitate a person skilled in the art to which the present invention pertains.

As described above, in the conventional method of polymerizing polyamide, the ratio of process steps due to problems caused by hydrolytic polymerization, catalytic ring opening polymerization, and anionic ring opening polymerization There is a limitation in limiting the increase in viscosity due to the efficiency and the side reaction in the high-temperature polymerization.

In the present invention, by using carbon dioxide (CO ₂ ) without using a solvent as a catalyst, an eco-friendly process enables high-molecular polymerization with a high molecular weight to have a high conversion ratio within a short polymerization time Thereby solving the above-mentioned problem.

According to the present invention, there is provided a process for producing polyamide by anionic polymerization comprising reacting 0.01 to 20 parts by weight of an alkali metal as an initiator, 0.3 to 10 parts by weight of a molecular weight adjuster, 0.002 To 1.0 part by weight of anionic ring-opening polymerization.

Specifically, the compositions included in the polyamide production by anion ring-opening polymerization according to the present invention will be described below.

First, the lactam according to the present invention can be preferably used as a monomer for producing a polyamide. However, the lactam according to the present invention is not limited thereto, and includes 4 to 12 carbon atoms in the ring. Examples thereof include caprolactam, Propiolactam, 2-pyrrolidone, valerolactam, caprolactam, caprolactam, caprolactam, caprolactam, caprolactam, caprolactam, May include caprolactam, heptanolactam, octanolactam, nonanolactam, decanolactam, undecanolactam, and dodecanolactam. have.

The lactam according to the present invention may comprise at least one or more selected from the group consisting of caprolactam, laurolactam, pyrrolidone and piperidone. For example, a mixture of caprolactam and laurolactam can be used, but is not limited thereto.

The lactam is composed of two kinds, and at least one lactam may include at least 50 parts by weight based on 100 parts by weight of the total lactam.

For example, the lactam may be of two kinds, and the two lactams may be caprolactam and laurolactam. Any one of them may contain 50 parts by weight or more of lactam, for example, 90 parts by weight and 10 parts by weight of caprolactam and laurolactam. However, the present invention is not limited thereto.

The alkali metal catalyst according to the present invention is an initiator for producing a polyamide and is a compound which permits the formation of the lactam anion, and is a metal hydride, a metal hydroxide and a metal alkoxide And at least one selected from the group consisting of

In a specific example, the metal hydride may comprise sodium hydride and potassium hydride, wherein the metal hydroxide is selected from the group consisting of sodium hydroxide and potassium hydroxide < RTI ID = 0.0 > ), And the metal alkoxide may include, but is not limited to, potassium tert-butoxide and aluminum isopropoxide.

Such as sodium caprolactamate or potassium caprolactamate, alkaline earth metal caprolactamates such as magnesium bromide caprolactamate, magnesium chloride caprolactamate, or magnesium biscaprolactamate, alkali metals such as sodium or potassium, alkali metal bases, For example sodium hydride, sodium hydride, sodium hydroxide, sodium methanolate, sodium ethanolate, sodium propanolate or sodium butanolate or potassium base such as potassium hydride, potassium, potassium hydroxide, potassium methanolate, Potassium ethanolate, potassium propanolate, potassium butanolate, or a mixture thereof, preferably sodium caprolactamate, potassium caprolactamate, magnesium bromide caprolactamate, magnesium Sodium hydroxide, sodium hydroxide, sodium methanolate, sodium propanolate, sodium butanolate, potassium hydroxide, potassium hydroxide, potassium methanolate, potassium ethanolate, potassium carbonate, , Potassium propanolate, potassium butanolate, or a mixture thereof. Also, it may include at least one selected from the group consisting of sodium hydride, sodium, and sodium caprolactamate, and mixtures thereof.

Such metal catalysts can be used in solid form or as a solution, and it is preferable to use the catalyst in the form of a solid. The catalyst is preferably added to the laurolactam melt, in which the catalyst can be dissolved. These catalysts result in particularly fast reactions, thereby increasing the efficiency of the manufacturing process for the polyamides according to the invention.

According to the present invention, the alkali metal catalyst may be contained in an amount of 0.01 to 20 parts by weight based on 100 parts by weight of the total lactam. Preferably 0.03 to 10 parts by weight, and more preferably 0.05 to 5.0 parts by weight.

If the alkali metal catalyst is added in an amount of less than 0.01 part by weight, there may be a problem of unreacted or reduced reaction rate. If the alkali metal catalyst is more than 20 parts by weight, there may be a problem of generating a low molecular weight polymer The above range is good.

Next, the molecular weight modifier according to the present invention may be ethylene-bis-stearamide (EBS), but is not limited thereto, and may be an amine compound, a urea compound And a di-urea compound.

According to the present invention, the molecular weight modifier may be contained in an amount of 0.3 to 10 parts by weight based on 100 parts by weight of the total lactam. Preferably 0.4 to 7.0 parts by weight, and more preferably 0.5 to 3.0 parts by weight.

When the molecular weight modifier is added in an amount of less than 0.3 part by weight, there may be a problem of a high molecular weight polymer or gelation. If the molecular weight adjuster is more than 10 parts by weight, there may be a problem of low molecular weight polymer formation or non- The above range is good.

Finally, according to the present invention, the activator may be preferably carbon dioxide (CO2), but is not limited thereto. For example, benzoyl chloride, N-acetyl caprolactam ), N-acetyl laurolactam, octadecyl isocyanate (SIC), toluene diisocyanate (TDI), and hexamethylene diisocyanate (HDI). At least one kind selected from the group consisting of

According to the present invention, the carbon dioxide may be contained in an amount of 0.002 to 1.0 part by weight based on 100 parts by weight of the total lactam. Preferably 0.005 to 5 parts by weight, and more preferably 0.01 to 0.1 part by weight.

If the carbon dioxide is added in an amount of less than 0.002 parts by weight, there may be a problem of unreacted or slowed reaction rate. If the amount of carbon dioxide exceeds 1.0 part by weight, gelation may occur.

Hereinafter, exemplary embodiments of the present invention will be described in order to facilitate understanding of the present invention. However, the following examples are intended to aid understanding of the present invention, and the present invention is not limited by the following experimental examples.

[Example]

≪ Example 1 >

Preparation of Polymerization Samples Using Carbon Dioxide (CO ₂ ) as Activator

After removing the vacuum in a flask maintained at 60 ° C in a vacuum to remove moisture in the flask, 20 g of laurolactam, 0.15 g of EBS and 0.02 g of NaH were added and the temperature was raised to 160 ° C under vacuum. Next, the reaction temperature was set to 230 ° C, nitrogen gas was added, and the hydrogen gas generated by melting the materials was removed. Then, 1.7 ml of carbon dioxide was injected and reacted for 30 minutes. After 30 minutes, the reaction was completed by adding an aqueous formic acid solution (formic acid: distilled water = 1: 1) to the flask, and a sample having the content shown in Table 1 was recovered. The polydispersity index (PDI) was confirmed using the molecular weight and molecular weight distribution, and the results are shown in Table 2 below.

	Lactam (g)	Alkali metal (g)	Molecular weight regulator (g)	CO 2 content (ml)
Example 1	Laurolactam 20	0.02	0.15	1.7
Example 2	Laurolactam 20	0.04	0.30	3.4
Example 3	Laurolactam 20	0.002	0.15	1.7
Example 4	Laurolactam 20	0.05	0.15	1.7
Example 5	Laurolactam 20	0.09	0.15	1.7
Example 6	Laurolactam 20	0.02	0.05	1.7
Example 7	Laurolactam 20	0.02	0.6	1.7
Example 8	Laurolactam 20	0.02	0.9	1.7
Example 9	Laurolactam 20	0.02	0.15	0.2
Example 10	Laurolactam 20	0.02	0.15	6
Example 11	Laurolactam 20	0.02	0.15	100
Example 12	Laurolactam 2 Caprolactam 18	0.04	0.30	3.4
Comparative Example 1	20	0.02	-	1.7
Comparative Example 2	20	0.02	0.15	-
Comparative Example 3	20	-	0.15	1.7

≪ Example 2 >

Preparation of Polymerization Samples Using Carbon Dioxide (CO ₂ ) as Activator

A polymerization sample was prepared in the same manner as in Example 1 except that 0.30 g of EBS and 0.04 g of NaH were added.

≪ Examples 3 to 11 >

A polymerized sample was prepared in the same manner as in Example 1 except that the content ratio of the composition was changed as shown in Table 1.

≪ Example 12 >

A polymerization sample was prepared in the same manner as in Example 2, except that 2 g and 18 g of laurolactam and caprolactam, respectively, were added as monomers.

[Comparative Example]

≪ Comparative Example 1 &

A polymerization sample was prepared in the same manner as in Example 1, except that EBS was not used.

≪ Comparative Example 2 &

A polymerized sample was prepared in the same manner as in Example 1, except that the reaction was carried out for 30 minutes without carbon dioxide injection.

≪ Comparative Example 3 &

A polymerization sample was prepared in the same manner as in Example 1 except that NaH was added.

	Molecular weight (g / mol)	Molecular weight distribution (PDI)	polymerization
Example 1	73,500	2.5	polymerization
Example 2	53,900	2.5	polymerization
Example 3	-	-	Uncopolymerization
Example 4	43,000	-	polymerization
Example 5	20,000	-	polymerization
Example 6	> 160,000	-	Gelling
Example 7	18,000	-	polymerization
Example 8	12,000	-	polymerization
Example 9	-	-	Uncopolymerization
Example 10	85,000	2.5	polymerization
Example 11	> 160,000	-	Gelling
Example 12	48,000	2.5	polymerization
Comparative Example 1	> 160,000	6.5	Gelling
Comparative Example 2	-	-	Uncopolymerization
Comparative Example 3	-	-	Uncopolymerization

As shown in Table 2, Example 5 containing NaH as 0.09 as the Laurolactam was found to have a somewhat lower molecular weight as compared to Examples 1 to 4. In addition, with respect to the laurolactam, Example 8 containing 0.9 of EBS showed a lower molecular weight as compared to Examples 6 to 7, and with respect to the laurolactam, carbon dioxide (CO ₂ ) in 12 ml was shown to have a higher molecular weight as compared to Examples 9 to 10.

In addition, in the case of Comparative Example 1, which does not contain EBS as a molecular weight modifier, the molecular weight distribution was extremely broad as compared with Examples 1 to 11. In Comparative Example 3 in which NaH, which is an alkali metal, was not included, In the case of Comparative Example 2, which was not included, the results showed that polymerization did not proceed.

Finally, in the case of Example 12, it was confirmed that even when a mixture of laurolactam and caprolactam was used as a monomer, the polymerization proceeded to a satisfactory level of molecular weight and PDI.

As shown in FIG. 1, the weight average molecular weight (Mw) was 73,500 and the polydispersity index (PDI) was 2.5 as determined by GPC analysis of the polymer samples prepared as described above.

Also, as shown in FIG. 2 to FIG. 3, DSC analysis of the polymer samples showed a Tm value of 179 ° C., and the remaining oligomer after polymerization was 5.1%, indicating a polymerization conversion of about 95%.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

Claims (14)

1. As a method for producing polyamide by anionic polymerization,

   A process for producing a polyamide by anion ring-opening polymerization comprising, as an initiator, 0.01 to 20 parts by weight of an alkali metal, 0.3 to 10 parts by weight of a molecular weight modifier, and 0.002 to 1.0 part by weight of carbon dioxide as an activator, based on 100 parts by weight of the lactam as a whole.
2. The method according to claim 1,

   Wherein the lactam comprises at least one member selected from the group consisting of caprolactam, laurolactam, pyrrolidone, and piperidone.
3. 3. The method of claim 2,

   Wherein the lactam is composed of two kinds, and at least one lactam is contained in an amount of not less than 50 parts by weight based on 100 parts by weight of the total lactam.
4. The method according to claim 1,

   The activator may be selected from the group consisting of benzoyl chloride, N-acetyl caprolactam, N-acetyl laurolactam, octadecyl isocyanate (SIC), toluene diisocyanate and at least one selected from the group consisting of toluene diisocyanate (TDI) and hexamethylene diisocyanate (HDI).
5. The method according to claim 1,

   Wherein the alkali metal comprises at least one member selected from the group consisting of a metal hydride, a metal hydroxide and a metal alkoxide. Way.
6. The method according to claim 1,

   The molecular weight modifier may be at least one selected from the group consisting of ethylene-bis-stearamide (EBS), amine compound, urea compound and di- Wherein the polyamide is produced by anionic ring-opening polymerization.
7. The method according to claim 1,

   Wherein the polymerization reaction is carried out within a range of 0.5 to 120 minutes.
8. The method according to claim 1,

   Wherein the lactam in the polymerization reaction has a conversion of at least 95% to polyamide.
9. The method according to claim 1,

   Wherein the polymerization temperature in the polymerization reaction is in the range of 180 to 300 占 폚.
10. A polyamide produced by the process for producing a polyamide according to any one of claims 1 to 9.
11. 11. The method of claim 10,

    Wherein the polyamide has a molecular weight distribution of 3.0 or less.
12. 11. The method of claim 10,

    Wherein the polyamide has a weight average molecular weight (Mw) in the range of 20,000 to 100,000 or less.
13. 11. The method of claim 10,

    Wherein the polyamide has a linear, branched, hyperbranched or dendritic structure.
14. A material for a vehicle, a material for an electronic device, an industrial pipe material, an architectural civil engineering material, a 3D printer material, a fiber material, a cladding material, a machine tool material, a medical material, Wherein the material is selected from the group consisting of solar cell material, solar cell material, battery material, sports material, household electrical material, household material, and cosmetic material.

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