JP2014005385A - Polyacetal resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyacetal resin composition that can suppress generation of formaldehyde and contamination of a mold at fabrication.SOLUTION: A polyacetal resin composition includes (B) 0.05-5 parts by mass of a compound shown by the following formula (1) based on (A) 100 mass of a polyacetal resin. In the formula (1), m denotes 0 or 1; n denotes a positive integer; Ris a (m+n)-valent group, and denotes a 1-40C aliphatic hydrocarbon group or the like; Ris a univalent group, and denotes a 1-40C aliphatic hydrocarbon group or the like; and Y denotes a hydrazide residue.

Description

  The present invention relates to a polyacetal resin composition.

  The engineering plastics polyacetal resin has excellent mechanical properties, sliding properties, friction and wear properties, heat resistance, moldability and the like. For this reason, the polyacetal resin composition containing polyacetal resin is widely used for various machine parts, electrical parts, etc., such as a motor vehicle and OA apparatus.

  However, since polyacetal resin uses formaldehyde as its main raw material, it causes a slight thermal decomposition reaction due to a thermal history during processing and the like, and generates a very small amount of formaldehyde. Here, since formaldehyde may cause sick house syndrome and the like, a polyacetal resin composition capable of sufficiently suppressing the generation of formaldehyde is demanded.

  As such a polyacetal resin composition, what is disclosed by the following patent document 1 is known. In the following Patent Document 1, it is proposed to suppress the amount of formaldehyde generated from a molded product by using a polyacetal resin composition in which a hydrazide compound and an isocyanate compound are blended with a polyacetal resin.

JP 2008-156489 A

  However, the polyacetal resin composition described in Patent Document 1 still has room for improvement in terms of suppressing the generation of formaldehyde.

  A mold is used when molding the polyacetal resin composition. At this time, the mold may be contaminated by adhesion of a compound generated by a thermal decomposition reaction during the molding process. When a molded product is repeatedly produced using this contaminated mold, the deposits attached to the mold are transferred as foreign matter to the molded product to be molded later, and in the worst case, it is necessary to discard the molded product. Become. Since the disposal of the molded product leads to a decrease in the yield of the molded product, it is desirable that the polyacetal resin composition can sufficiently suppress the contamination of the mold.

  For this reason, the polyacetal resin composition which can fully suppress generation | occurrence | production of formaldehyde and can fully suppress the contamination of the metal mold | die at the time of a shaping | molding process was desired.

  This invention is made | formed in view of the said situation, and it aims at providing the polyacetal resin composition which can fully suppress generation | occurrence | production of formaldehyde, and can fully suppress the contamination of the metal mold | die at the time of a shaping | molding process. .

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a specific ratio of a compound containing a group having a hydrazine moiety and an amide bond and having a terminal such as a hydrocarbon group with respect to the polyacetal resin. It was found that by mixing with the above, generation of formaldehyde and contamination of the mold during molding can be sufficiently suppressed, and the present invention has been completed.

（前記式（１）中、ｍは０又は１を表し、ｎは正の整数を表す。Ｒ^１は（ｍ＋ｎ）価の基であって、炭素数１〜４０の脂肪族炭化水素基、炭素数３〜４０の脂環式炭化水素基、炭素数６〜１０の芳香族炭化水素基、炭素数２〜５の複素環基、又は、−ＣＺ^１Ｚ^２−ＣＺ^３Ｚ^４−を構成単位として含むポリマーの主鎖を表す。ｍ＝１、ｎ＝１である場合、Ｒ^１は単結合であってもよい。ｍ＝０、ｎ＝１である場合、Ｒ^１は水素原子であってもよい。Ｚ^１〜Ｚ^４はそれぞれ独立に、単結合、水素原子又は炭素数１〜１０のアルキル基を表し、Ｚ^１〜Ｚ^４のうち少なくとも１つは単結合を表す。Ｒ^２は、一価の基であって、炭素数１〜４０の脂肪族炭化水素基、炭素数３〜４０の脂環式炭化水素基、炭素数６〜１０の芳香族炭化水素基、炭素数２〜５の複素環基又は下記式（１−Ａ）で表される基を表す。Ｙは、下記式（１−Ｂ）で表される基を表す。）

（前記式（１−Ａ）中、Ｒ^３は、二価の基であって、炭素数１〜４０の脂肪族炭化水素基、炭素数３〜１０の脂環式炭化水素基、炭素数６〜１０の芳香族炭化水素基、炭素数２〜５の複素環基を表す。またＲ^４は、一価の基であって、炭素数１〜４０の脂肪族炭化水素基、炭素数３〜４０の脂環式炭化水素基、炭素数６〜１０の芳香族炭化水素基、炭素数２〜５の複素環基を表す。）

That is, the present invention is a polyacetal resin composition in which 0.05 to 5 parts by mass of the compound represented by the following formula (1) is blended with respect to 100 parts by mass of (A) polyacetal resin.

(In the formula (1), m represents 0 or 1, n represents a positive integer. R ¹ is a (m + n) -valent group, an aliphatic hydrocarbon group having 1 to 40 carbon atoms, carbon A structural unit comprising an alicyclic hydrocarbon group having 3 to 40 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, a heterocyclic group having 2 to 5 carbon atoms, or —CZ ¹ Z ² —CZ ³ Z ⁴ — In the case where m = 1 and n = 1, R ¹ may be a single bond, and when m = 0 and n = 1, R ¹ is a hydrogen atom. respectively which may ^.Z 1 to Z ⁴ are independently a single bond, represents a hydrogen atom or an alkyl group having 1 to 10 carbon ^atoms, .R ² representative of at least one single bond of Z 1 to Z ⁴ are, A monovalent group, an aliphatic hydrocarbon group having 1 to 40 carbon atoms, an alicyclic hydrocarbon group having 3 to 40 carbon atoms, and an aromatic hydrocarbon group having 6 to 10 carbon atoms .Y represents a group represented by a heterocyclic group or the following formula 2 to 5 carbon atoms (1-A) represents a group represented by the following formula (1-B).)

In (Formula (1-A), ^{R 3} is a divalent group, aliphatic hydrocarbon group having 1 to 40 carbon atoms, alicyclic hydrocarbon group having 3 to 10 carbon atoms, 6 carbon atoms Represents an aromatic hydrocarbon group having 10 to 10 carbon atoms, a heterocyclic group having 2 to 5 carbon atoms, and R ⁴ is a monovalent group, an aliphatic hydrocarbon group having 1 to 40 carbon atoms, and 3 to 3 carbon atoms. 40 represents an alicyclic hydrocarbon group, an aromatic hydrocarbon group having 6 to 10 carbon atoms, and a heterocyclic group having 2 to 5 carbon atoms.)

  According to the polyacetal resin composition of the present invention, generation of formaldehyde and contamination of the mold during molding can be sufficiently suppressed.

  Although the reason why the above effect is obtained is not clear, the present inventor presumes as follows.

When the polyacetal resin composition is heated and melted for molding, part of the polyacetal resin undergoes a thermal decomposition reaction to generate formaldehyde. The generated formaldehyde is consumed by reacting with the compound represented by the above formula (1) in the polyacetal resin composition. At this time, since R ² is not a hydrogen atom but a hydrocarbon group or the like, the reactivity between formaldehyde and the compound (B) as compared with the case where the hydrazide compound and the isocyanate compound are separately added to the polyacetal resin. As a result, generation of formaldehyde from the polyacetal resin composition is sufficiently suppressed. Further, the product obtained by the reaction of the compound represented by the above formula (1) and formaldehyde hardly bleeds out from the polyacetal resin composition at the time of molding, or hardly adheres to the mold even if bleeded out.

  As a result, the present inventors speculate that according to the polyacetal resin composition of the present invention, the generation of formaldehyde and the contamination of the mold during the molding process can be sufficiently suppressed.

  In the polyacetal resin composition, the compound represented by the formula (1) is preferably an adduct of a hydrazide compound and an isocyanate compound.

  In this case, it can be more easily produced as compared with the case where the compound represented by the formula (1) is other than the above adduct.

（前記式（２）〜（４）中、Ｒ^２及びＲ^１２は、式（１）におけるＲ^２と同義であり、前記式（４）においては互いに同一でも異なっていてもよい。Ｒ^１１は、一価の基であって、水素原子、炭素数１〜４０の脂肪族炭化水素基、炭素数３〜４０の脂環式炭化水素基、炭素数６〜１０の芳香族炭化水素基又は炭素数２〜５の複素環基を表す。Ｒ^２１は、二価の基であって、単結合、炭素数１〜４０の脂肪族炭化水素基、炭素数３〜１０の脂環式炭化水素基、炭素数６〜１０の芳香族炭化水素基又は炭素数２〜５の複素環基を表す。） In the polyacetal resin composition, the compound represented by the formula (1) is at least one compound selected from the group consisting of compounds represented by the following general formulas (2) to (4). Is preferred.

(Wherein (2) ~ (4), ^{R 2} and ^{R 12} has the same meaning as ^{R 2} in the formula (1), the formula (4) may ^{.R 11} be the same as or different from each other in A monovalent group, a hydrogen atom, an aliphatic hydrocarbon group having 1 to 40 carbon atoms, an alicyclic hydrocarbon group having 3 to 40 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, or carbon Represents a heterocyclic group having 2 to 5. R ²¹ is a divalent group, a single bond, an aliphatic hydrocarbon group having 1 to 40 carbon atoms, an alicyclic hydrocarbon group having 3 to 10 carbon atoms. Represents an aromatic hydrocarbon group having 6 to 10 carbon atoms or a heterocyclic group having 2 to 5 carbon atoms.)

  In this case, generation | occurrence | production of formaldehyde and the contamination of the metal mold | die at the time of shaping | molding process can be suppressed more effectively.

In the formula (2) to (4), it is preferred that ^{R 2} and ^{R 12} are each aliphatic hydrocarbon group having 1 to 40 carbon atoms.

In the formula (2) to (4), when ^{R 2} and ^{R 12} is an aliphatic hydrocarbon group of 1 to 40 carbon atoms, ^{R 2} and ^{R 12} is other than an aliphatic hydrocarbon group of 1 to 40 carbon atoms Since the steric hindrance due to R ² and R ¹² is smaller than in the case of the group, the compounds represented by the formulas (2) to (4) are more reactive with formaldehyde, further reducing the generation of formaldehyde. It can be effectively suppressed.

  In the said polyacetal resin composition, it is preferable that 0.01-3 mass parts of heat stabilizers (C) are mix | blended with respect to 100 mass parts of said polyacetal resins.

  In this case, compared with the case where the amount of the heat stabilizer (C) is less than 0.01 parts by mass, the thermal decomposition of the polyacetal resin is more effectively suppressed, and the generation of formaldehyde is more effectively suppressed. . Moreover, compared with the case where the compounding quantity of a heat stabilizer (C) exceeds 3 mass parts, the mechanical characteristic of a polyacetal resin composition can be improved more.

  The heat stabilizer (C) is preferably at least one heat stabilizer selected from the group consisting of hindered phenol compounds and triazine compounds.

  In this case, deterioration of the polyacetal resin composition is effectively suppressed.

  In the said polyacetal resin composition, it is preferable that 0.01-3 mass parts of mold release agents (D) are mix | blended with respect to 100 mass parts of said polyacetal resins.

  In this case, contamination of the mold during the molding process is more effectively suppressed as compared with the case where the amount of the release agent (D) is less than 0.01 parts by mass. Moreover, compared with the case where the compounding quantity of a mold release agent (D) exceeds 3 mass parts, the mechanical characteristic of a polyacetal resin composition can be improved more.

  The release agent (D) is preferably at least one release agent selected from the group consisting of polyethylene, silicone oil, fatty acid, fatty acid ester, and fatty acid metal salt.

  In this case, contamination of the mold during the molding process is further effectively suppressed.

  In the said polyacetal resin composition, it is preferable that 0.01-3 mass parts of anti-stabilizers (E) are mix | blended with respect to 100 mass parts of polyacetal resins.

  In this case, the deterioration of the polyacetal resin composition is sufficiently suppressed as compared with the case where the blending amount of the anti-glare stabilizer (E) is less than 0.01 parts by mass. Moreover, compared with the case where the compounding quantity of a weather-resistant stabilizer (E) exceeds 3 mass parts, the mechanical characteristic of a polyacetal resin composition can be improved more.

（前記式（５）中、Ｒ^６は窒素原子との結合部が炭素原子である有機基、Ｘは酸素原子若しくは窒素原子を介してピペリジル基の４−位と結合する有機基又は水素原子を表す。） In the polyacetal resin composition, the hindered amine light stabilizer is preferably a hindered amine light stabilizer represented by the following general formula (5).

(In the formula (5), R ⁶ represents an organic group in which the bonding portion to the nitrogen atom is a carbon atom, X represents an organic group or hydrogen atom bonded to the 4-position of the piperidyl group via an oxygen atom or a nitrogen atom. Represents.)

  In this case, deterioration of the polyacetal resin composition is further effectively suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, the polyacetal resin composition which can fully suppress generation | occurrence | production of formaldehyde and can fully suppress the contamination of the metal mold | die at the time of a shaping | molding process can be provided.

It is a graph showing ¹ H-NMR spectrum of B-3. It is a graph showing ¹ H-NMR spectrum of B-4.

  Hereinafter, the present invention will be described in detail.

The present invention is a polyacetal resin composition in which 0.05 to 5 parts by mass of (B) a compound represented by the following formula (1) is blended with respect to 100 parts by mass of (A) polyacetal resin.

In the above formula (1), m represents 0 or 1, and n represents a positive integer. R ¹ is an (m + n) -valent group, an aliphatic hydrocarbon group having 1 to 40 carbon atoms, an alicyclic hydrocarbon group having 3 to 40 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, heterocyclic group having 2 to 5 carbon atoms, ^{or, -CZ 1 Z 2 -CZ 3 Z} 4 - represents the backbone of a polymer containing, as a structural unit. When m = 1 and n = 1, R ¹ may be a single bond. When m = 0 and n = 1, R ¹ may be a hydrogen atom. Z ^{1 to} Z ⁴ each independently represents a single bond, a hydrogen atom or an alkyl group of 1 to 10, and at least one of Z ^{1 to} Z ⁴ represents a single bond. R ² is a monovalent group, an aliphatic hydrocarbon group having 1 to 40 carbon atoms, an alicyclic hydrocarbon group having 3 to 10 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, carbon It represents a group represented by a heterocyclic group of formula 2-5 or the following formula (1-A). Y represents a group represented by the following formula (1-B).

In said formula (1-A), R < ³ > is bivalent group | bases, Comprising: A C1-C40 aliphatic hydrocarbon group, C3-C40 alicyclic hydrocarbon group, C6-C6 Represents an aromatic hydrocarbon group having 10 carbon atoms or a heterocyclic group having 2 to 5 carbon atoms. R ⁴ is a monovalent group and is an aliphatic hydrocarbon group having 1 to 40 carbon atoms, an alicyclic hydrocarbon group having 3 to 40 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, or Represents a heterocyclic group having 2 to 5 carbon atoms.

  According to this polyacetal resin composition, generation of formaldehyde and contamination of the mold during molding can be sufficiently suppressed.

  Next, the polyacetal resin (A) and the compound (B) used in the polyacetal resin composition of the present invention will be described in detail.

(A) Polyacetal resin The polyacetal resin used in the polyacetal resin composition of the present invention is not particularly limited, and even if it is a homopolymer containing only a divalent oxymethylene group as a constituent unit, a divalent oxymethylene The copolymer which contains a group and a C2-C6 bivalent oxyalkylene group as a structural unit may be sufficient.

  Examples of the oxyalkylene group having 2 to 6 carbon atoms include an oxyethylene group, an oxypropylene group, and an oxybutylene group.

  In the polyacetal resin, the ratio of the oxyalkylene group having 2 to 6 carbon atoms in the total number of moles of the oxymethylene group and the oxyalkylene group having 2 to 6 carbon atoms is not particularly limited. What is necessary is just mol%.

  In order to produce the polyacetal resin, trioxane is usually used as a main raw material. In order to introduce an oxyalkylene group having 2 to 6 carbon atoms into the polyacetal resin, for example, cyclic formal or cyclic ether can be used. Specific examples of cyclic formal include 1,3-dioxolane, 1,3-dioxane, 1,3-dioxepane, 1,3-dioxocane, 1,3,5-trioxepane, 1,3,6-trioxocane and the like. Specific examples of the cyclic ether include ethylene oxide, propylene oxide and butylene oxide. In order to introduce an oxyethylene group into the polyacetal resin (A), for example, 1,3-dioxolane may be used, and in order to introduce an oxypropylene group, 1,3-dioxane may be used. For introduction, 1,3-dioxepane may be introduced.

(B) Compound The compound (B) blended in the polyacetal resin composition of the present invention is a compound represented by the above formula (1).
In the above formula (1), n may be a positive integer, but when R ¹ represents an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group or a heterocyclic group. , N is usually an integer of 1-4. When R ¹ represents a main chain of a polymer containing —CZ ¹ Z ² —CZ ³ Z ⁴ — as a structural unit, n is usually —CZ ¹ Z ² —CZ ³ Z contained in the main chain of the polymer. It is the same as the total number of single bonds in the total number of ^4- structural units.

In the above formula (1), the aliphatic hydrocarbon group represented by R ¹ may be saturated or unsaturated, and may be linear or branched.

  For example, when m + n is 1, the aliphatic hydrocarbon group is a monovalent aliphatic hydrocarbon group, and when m + n is 2, the aliphatic hydrocarbon group is a divalent aliphatic hydrocarbon group.

  Specific examples of the monovalent aliphatic hydrocarbon group include, for example, methyl group, ethyl group, n-propyl group, n-butyl group, n-hexyl group, n-octyl group, n-decyl group, undecyl group, n Linear alkyl groups such as -dodecyl group, n-hexadecyl group, n-eicosyl group, n-triacontyl group, n-tetracontyl group, branched alkyl groups such as i-propyl group, i-butyl group, t-butyl group Alkenyl groups such as 1-propenyl group and 1-butenyl group, alkynyl groups such as ethynyl group and 2-propynyl group.

  Specific examples of the divalent aliphatic hydrocarbon group include alkylene groups such as a methylene group, an ethylene group, a propylene group, a butylene group, a hexylene group, and a decylene group.

In the above formula (1), the alicyclic hydrocarbon group represented by R ¹ may be saturated or unsaturated. For example, when m + n is 1, the alicyclic hydrocarbon group is a monovalent alicyclic hydrocarbon group, and when m + n is 2, the alicyclic hydrocarbon group is a divalent alicyclic hydrocarbon group.

  Examples of the monovalent alicyclic hydrocarbon group include a cycloalkyl group having 3 to 40 carbon atoms and a cycloalkenyl group. Examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclodecyl group, a cyclododecyl group, a cyclohexadecyl group, a cycloeicosyl group, and a cyclotriacontyl group. , Cyclotetracontyl group, norbornyl group, adamantyl group and the like. Examples of the cycloalkenyl group include a 1-cyclohexenyl group.

  Examples of the divalent alicyclic hydrocarbon group include a cycloalkylene group having 3 to 18 carbon atoms.

In the above formula (1), the aromatic hydrocarbon group represented by R ¹ is a monovalent aromatic hydrocarbon group when m + n is 1, and the divalent aromatic carbon group when m + n is 2. It becomes a hydrogen group.

  Specific examples of the monovalent aromatic hydrocarbon group include aryl groups such as a phenyl group and a naphthyl group.

  Examples of the divalent aromatic hydrocarbon group include arylene groups such as a phenylene group and a naphthylene group.

  A substituent may be bonded to at least a part of the carbon atoms of the aromatic hydrocarbon group. Examples of the substituent include a halogen group, a nitro group, and an alkyl group having 1 to 40 carbon atoms.

In the above formula (1), the heterocyclic group represented by R ¹ is a (m + n) -valent group containing at least one atom selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom, This is formed by removing (m + n) hydrogen atoms from any carbon atom of the heterocyclic compound. Examples of such heterocyclic compounds include heterocyclic compounds containing nitrogen atoms such as piperidine, piperazine, pyridine, triazine, imidazole, pyrrole, carbazole, pyrrolidine, luminol, uracil, creatine, urea ring, lactam, isoniazid, and furan. , Heterocyclic compounds containing only oxygen atoms as heteroatoms such as tetrahydrofuran and dioxane, and heterocyclic compounds containing sulfur atoms such as thiophene. Among these, a heterocyclic group containing a nitrogen atom is particularly preferable. In this case, the reactivity between the compound (B) and formaldehyde becomes higher, and the generation of formaldehyde can be more effectively suppressed.

In the above formula (1), the main chain of the polymer represented by R ¹ may be a main chain containing —CZ ¹ Z ² —CZ ³ Z ⁴ — as a structural unit. Here, Z ^{1 to} Z ⁴ each independently represent a single bond, a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and at least one of Z ^{1 to} Z ⁴ represents a single bond. -C (O) NHCONHR ² and Y of the general formula (1) are bonded to this single bond. Specific examples of the hydrazide compound containing the main chain of such a polymer as R ¹ include, for example, poly (methacrylic acid-2-methylhydrazide), poly (acrylic acid-2-methylhydrazide), and poly (ethyleneethylacrylic acid hydrazide). ) And the like.

In the above formula (1-A), the aliphatic hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group represented by R ³ are the divalent groups represented by R ¹ in formula (1). This is the same as the aliphatic hydrocarbon group, divalent alicyclic hydrocarbon group, divalent aromatic hydrocarbon group, and divalent heterocyclic group. In the above formula (1-A), the aliphatic hydrocarbon group, alicyclic hydrocarbon group, and aromatic hydrocarbon group represented by R ⁴ are monovalent represented by R ¹ in formula (1). And the same as the aliphatic hydrocarbon group, monovalent alicyclic hydrocarbon group, monovalent aromatic hydrocarbon group, and monovalent heterocyclic group.

  The compound (B) is preferably an adduct of a hydrazide compound and an isocyanate compound. In this case, it becomes possible to produce the compound (B) more easily than when the compound (B) is other than the above adduct.

ここで、式（２）で表される化合物は、式（１）においてｍ＝０、ｎ＝１、Ｒ^１をＲ^１１とした化合物であり、式（３）で表される化合物は、式（１）においてｍ＝１、ｎ＝１、Ｒ^１をＲ^２１とした化合物であり、式（４）で表される化合物は、式（１）においてｍ＝０、ｎ＝２、Ｒ^１をＲ^２１とした化合物である。 It is preferable that the said compound is a compound shown by following formula (2)-(4).

Here, the compound represented by the formula (2) is a compound in which m = 0, n = 1, and R ¹ is R ¹¹ in the formula (1), and the compound represented by the formula (3) is represented by the formula In (1), m = 1, n = 1, and R ¹ is R ^{21. The} compound represented by formula (4) is m = 0, n = 2, R ¹ in formula (1). R ²¹ is the compound.

In the above formulas (2) to (4), R ² and R ¹² have the same meaning as R ² in the formula (1), and may be the same as or different from each other in the above formula (4). R ¹¹ is a monovalent group and is a hydrogen atom, an aliphatic hydrocarbon group having 1 to 40 carbon atoms, an alicyclic hydrocarbon group having 3 to 40 carbon atoms, or an aromatic hydrocarbon having 6 to 10 carbon atoms. Represents a group or a heterocyclic group having 2 to 5 carbon atoms. R ²¹ is a divalent group, and is a single bond, an aliphatic hydrocarbon group having 1 to 40 carbon atoms, an alicyclic hydrocarbon group having 3 to 40 carbon atoms, or an aromatic hydrocarbon having 6 to 10 carbon atoms. Represents a group or a heterocyclic group having 2 to 5 carbon atoms.

In this case, generation | occurrence | production of formaldehyde and the contamination of the metal mold | die at the time of shaping | molding process can be suppressed more effectively.
In the formulas (2) to (4), the aliphatic hydrocarbon group represented by R ¹¹ or R ²¹ preferably has 5 to 20 carbon atoms, and more preferably 6 to 15 carbon atoms.
In the formulas (2) to (4), the alicyclic hydrocarbon group represented by R ¹¹ or R ²¹ preferably has 3 to 20 carbon atoms, and more preferably 6 to 10 carbon atoms.

In the formula (2) to (4), it is preferred that ^{R 2} and ^{R 12} is an aliphatic hydrocarbon group of 1 to 40 carbon atoms.

In the formula (2) to (4), when ^{R 2} and ^{R 12} is an aliphatic hydrocarbon group of 1 to 40 carbon atoms, ^{R 2} and ^{R 12} is other than an aliphatic hydrocarbon group of 1 to 40 carbon atoms Since the steric hindrance due to R ² and R ¹² is smaller than in the case of the group, the reactivity of the above compound to formaldehyde is further increased, and generation of formaldehyde can be further effectively suppressed.

  Here, the aliphatic hydrocarbon group is preferably a linear alkyl group.

  In this case, the reactivity between the compounds represented by the above formulas (2) to (4) and formaldehyde becomes higher, and the generation of formaldehyde is more effectively suppressed.

  Moreover, when an aliphatic hydrocarbon group is a linear alkyl group, carbon number of an aliphatic hydrocarbon group becomes like this. More preferably, it is 1-20, More preferably, it is 1-15.

  The compounds represented by the above formulas (2) to (4) may be blended alone or in combination of two or more.

  Of the compounds represented by the above (2) to (4), the compound represented by the above formula (3) is preferable.

  In this case, compared with the case where the compound represented by the formula (2) or (4) is used, the reactivity between the compound represented by the compound (3) and formaldehyde can be further increased, and generation of formaldehyde can be reduced. It can be suppressed more sufficiently.

  The compounding quantity of a compound (B) is 0.05-5 mass parts with respect to 100 mass parts of polyacetal resins. When the compounding quantity of a compound (B) is less than 0.05 mass part, generation | occurrence | production of formaldehyde cannot fully be suppressed. Moreover, when the compounding quantity of a compound (B) is 5 mass parts or more, a bleed out generate | occur | produces at the time of a shaping | molding process, and a metal mold | die is contaminated.

  The compounding amount of the compound (B) is preferably 0.07 to 4 parts by mass, and more preferably 0.1 to 3 parts by mass.

  Next, a method for producing the compound represented by the above formula (1) will be described.

The compound represented by the formula (1) can be synthesized, for example, by adding a hydrazide compound and an isocyanate compound. Details will be described below.
The isocyanate compound is not particularly limited, but monovalent or divalent linear saturated isocyanate is preferably used.

  Specific examples of the isocyanate compound include methyl isocyanate, ethyl isocyanate, propyl isocyanate, butyl isocyanate, hexyl isocyanate, octyl isocyanate, decyl isocyanate, dodecyl isocyanate, hexadecyl isocyanate, octadecyl isocyanate, Monovalent isocyanate compounds such as eicosyl isocyanate, 2-isocyanate ethyl methacrylate, phenyl isocyanate, methylene diisocyanate, ethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate, decamethylene diisocyanate, dodecamethylene diisocyanate , Hexadecamethylene diisocyanate, eicoshark Divalent isocyanates such as diisocyanate, methylenebis (4,1-cyclohexanediyl) diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,5-naphthalenediyl diisocyanate, 3,3'-dimethylbiphenyl-4,4'-diyl diisocyanate Compound etc. are mentioned.

  The usage-amount of the said diisocyanate compound is adjusted as follows by the kind of compound to obtain.

  When obtaining one molecule of a monovalent hydrazide compound and a condensed compound of one molecule of a monovalent isocyanate compound, the amount of the isocyanate compound used may be 1 mol with respect to 1 mol of hydrazide.

  When obtaining an addition compound of two monovalent hydrazide compounds and one molecule of a divalent isocyanate compound, the amount of the isocyanate compound used may be 0.5 mol with respect to 1 mol of hydrazide.

  In the case of obtaining an addition compound of one molecule of a divalent hydrazide compound and one molecule of a monovalent isocyanate compound, the amount of the isocyanate compound used may be 1 mol with respect to 1 mol of hydrazide.

  When obtaining an addition compound of one molecule of a divalent hydrazide compound and two molecules of a monovalent isocyanate compound, the amount of the isocyanate compound used may be 2 mol per mol of hydrazide.

  Examples of the solvent used for the addition reaction between the hydrazide compound and the isocyanate compound include N, N-dimethylacetamide and N, N-dimethylformamide. Of these, N, N-dimethylacetamide is preferably used.

  In the addition reaction between the hydrazide compound and the isocyanate compound, both components of the hydrazide compound and the isocyanate compound may be charged in a reaction vessel in advance to obtain a reaction solution. Alternatively, the reaction solution containing one component may be added to the reaction solution. The reaction may be carried out while dropping one of the components, but it is preferred to obtain a reaction solution by reacting the reaction solution charged with the hydrazide compound while dropping the isocyanate compound. When the isocyanate compound is a solid, a solution dissolved in the solvent may be added dropwise. The reaction may be performed in an air atmosphere or an inert gas atmosphere such as nitrogen or argon. The reaction may be performed at normal pressure, under reduced pressure, or under pressure. The reaction temperature is preferably 20 to 80 ° C. When one reaction component or a solution thereof is dropped onto the other reaction component, the dropping rate of the reaction component or the solution is usually 0.1 mol / hour to 1 mol / hour per mole of the hydrazide compound.

  After completion of the reaction, the reaction solution is cooled to room temperature or lower, and if necessary, a poor solvent is added to precipitate compound crystals, which are filtered, washed with a solvent, and if necessary, further extracted, concentrated, recrystallized, column chromatography, etc. The compound can be obtained by purification by a known purification method.

  The polyacetal resin composition of this invention may contain at least 1 sort (s) of a heat stabilizer (C), a mold release agent (D), and a weathering stabilizer (E) as needed. Hereinafter, the heat stabilizer (C), the release agent (D) and the weathering stabilizer (E) will be described in detail.

(C) Heat stabilizer Although a heat stabilizer is not specifically limited, As a heat stabilizer, a hindered phenol compound or a triazine compound is used preferably. These may be blended singly or in combination of two or more. In this case, the generation of formaldehyde is further effectively suppressed.

The hindered phenol (sterically hindered phenol) compound is a compound having at least one structure in the molecule having a substituent at the ortho position with respect to the phenolic hydroxyl group represented by the following general formula (6).

In the above formula (6), R ⁷ and R ⁸ each independently represents a substituted or unsubstituted alkyl group.

Examples of the alkyl group represented by R ⁷ and R ⁸ include those having 1 to 6 carbon atoms such as a methyl group, an ethyl group, a propyl group, a butyl group, and an amyl group. Among them, a bulky branched alkyl group such as a t-butyl group is preferable, and at least one of R ⁷ and R ⁸ is preferably such a branched alkyl group. As the substituted alkyl group, a group in which a hydrogen atom of an unsubstituted alkyl group is substituted with a halogen atom such as chlorine can be used.

  Examples of the hindered phenol compound used in the present invention include 2,2′-methylene-bis (4-methyl-6-tert-butylphenol) and 4,4′-methylene-bis (2,6-di-tert-butylphenol). ), 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, 3,5-di-tert-butyl-4-hydroxybenzyldimethyl Amines, distearyl-3,5-di-t-butyl-4-hydroxybenzylphosphonate, diethyl-3,5-di-t-butyl-4-hydroxybenzylphosphonate, 2,6,7-trioxa-1-phospha -Bicyclo [2,2,2] -oct-4-yl-methyl-3,5-di-t-butyl-4-hydroxyhydrocinnamate, 3,5-di-t-butyl-4- Roxyphenyl-3,5-distearyl-thiotriazylamine, 2- (2-hydroxy-3,5-di-t-butylphenyl) -5-chlorobenzotriazole, 2,6-di-t-butyl- 4-hydroxymethylphenol, 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -1,3,5-triazine, N, N′-hexa Methylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamamide), octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,6-hexane Diol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], pentaerythritol-tetrakis [3- (3,5-di-t-butyl-4- Droxyphenyl) propionate], triethylene glycol-bis [3- (3,5-dimethyl-4-hydroxyphenyl) propionate], triethylene glycol-bis [3- (3-t-butyl-5-methyl-4 -Hydroxyphenyl) propionate], triethylene glycol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2'-thiodiethyl-bis [3- (3,5- Di-t-butyl-4-hydroxyphenyl) propionate] and the like.

Among these, a structure represented by the following general formula (7) such as N, N-hexamethylenebis (3,5-di-t-butyl-4-hydroxy-hydrocinnamamide) is preferable. It is a compound that has.

In the general formula (7), ^{R 7} and ^{R 8} each have the same meanings as ^{R 7} and ^{R 8} in the general formula (6).

  Also, 1,6-hexanediol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], pentaerythritol-tetrakis [3- (3,5-di-t-butyl- 4-hydroxyphenyl) propionate], triethylene glycol-bis [3- (3,5-dimethyl-4-hydroxyphenyl) propionate], triethylene glycol-bis [3- (3-t-butyl-5-methyl- 4-hydroxyphenyl) propionate], triethylene glycol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2′-thiodiethyl-bis [3- (3,5 3,5-dialkyl-4-hydride in the 3-position, such as -di-t-butyl-4-hydroxyphenyl) propionate] Also preferred are esters of propionic acid and polyhydric alcohols having a roxyphenyl group.

The triazine compound is basically a substituted triazine having a structure represented by the following general formula (8), or an initial polycondensate of the substituted triazine and formaldehyde.

In the general formula (8), R ⁹ , R ¹⁰ and R ¹¹ are each independently a hydrogen atom, halogen atom, hydroxyl group, mercapto group, alkyl group, aralkyl group, aryl group, cycloalkyl group, amino group or substituted. Represents an amino group, at least one of which represents an amino group or a substituted amino group.

  Specific examples of the amino-substituted triazine compound or the initial polycondensate of the amino-substituted triazine compound and formaldehyde include, for example, guanamine, melamine, N-butylmelamine, N-phenylmelamine, N, N-diphenylmelamine, N, N -Diallylmelamine, N, N ', N "-triphenylmelamine, N, N', N" -trimethylolmelamine, benzoguanamine, 2,4-diamino-6-methyl-sym-triazine, 2,4-diamino- 6-butyl-sym-triazine, 2,4-diamino-6-benzyloxy-sym-triazine, 2,4-diamino-6-butoxy-sym-triazine, 2,4-diamino-6-cyclohexyl-sym-triazine 2,4-diamino-6-chloro-sym-triazine, 2,4-diamidine 6-mercapto -sym- triazine, ammeline (N, N, N ', N'- tetra-cyanoethyl benzoguanamine), or the initial weight condensate thereof with formaldehyde. Among these, melamine, methylol melamine, benzoguanamine, and a water-soluble melamine-formaldehyde resin are particularly preferable.

  The blending amount of the heat stabilizer (C) is preferably 0.01 to 3 parts by weight, more preferably 0.05 to 2 parts by weight, and 0.1 to 1 part per 100 parts by weight of the polyacetal resin. More preferably, it is part by mass. When the blending amount of the heat stabilizer (C) is 0.01 to 3 parts by mass, the thermal decomposition of the polyacetal resin is less than when the blending amount of the heat stabilizer (C) is less than 0.01 parts by mass. It is more effectively suppressed and the generation of formaldehyde is more effectively suppressed. Moreover, compared with the case where the compounding quantity of a heat stabilizer (C) exceeds 3 mass parts, the mechanical characteristic of a polyacetal resin composition can be improved more.

(D) Release agent The release agent (D) is not particularly limited, but polyethylene, silicone oil, fatty acid, fatty acid ester, or fatty acid metal salt is preferably used as the release agent (D). These may be blended singly or in combination of two or more. In this case, contamination of the mold during the molding process is further effectively suppressed.

  Examples of the polyethylene include low molecular weight polyethylene, low molecular weight polyethylene copolymer, and modified polyethylene wax in which a polar group is introduced by oxidative modification or acid modification thereof. The number average molecular weight of polyethylene is preferably 500 to 15000, more preferably 1000 to 10,000.

  Polyethylene wax such as low molecular weight polyethylene and low molecular weight polyethylene copolymer is a method of directly polymerizing ethylene or ethylene and α-olefin using a Ziegler catalyst, a method of obtaining high molecular weight polyethylene or a by-product during the production of the copolymer Further, it can be produced by a method of thermally decomposing a high molecular weight polyethylene or copolymer. Such polyethylene wax is preferably a copolymer type polyethylene wax of 50 to 99 mol% of ethylene and 1 to 50 mol% of an α-olefin, and a particularly preferable polyethylene wax is a polyethylene wax in which the α-olefin is polypropylene.

  Oxidation-modified polyethylene wax is obtained by treating polyethylene wax with peroxide or oxygen to introduce polar groups such as carboxyl groups and hydroxyl groups. Acid-modified polyethylene wax is introduced with polar groups such as carboxyl groups and sulfonic acid groups by treatment with inorganic acids, organic acids or unsaturated carboxylic acids in the presence of peroxide or oxygen if necessary. It is. These polyethylene waxes are commercially available under the names of general type high density polyethylene wax, general type low density polyethylene wax, low oxidation type polyethylene wax, high oxidation type polyethylene wax, acid-modified type polyethylene wax or special monomer modified type. And can be easily obtained.

  Examples of silicone oil include silicone oil made of polydimethylsiloxane, silicone oil in which a part of methyl group of polydimethylsiloxane is substituted with phenyl group, part of methyl group of polydimethylsiloxane is hydrogen or 2 or more carbon atoms Silicone oil substituted with alkyl group, silicone oil with polydimethylsiloxane partially substituted with halogenated phenyl group, silicone oil with polydimethylsiloxane partially substituted with fluoroester group , Epoxy-modified silicone oils such as polydimethylsiloxane having epoxy groups, amino-modified silicone oils such as polydimethylsiloxane having amino groups, and alkylaralkylsilyls such as dimethylsiloxane and phenylmethylsiloxane Oil, polyether-modified silicone oil such as polydimethylsiloxane having a structure in which a part of methyl group of dimethylsiloxane unit is substituted with polyether, dimethyl in which part of methyl group of dimethylsiloxane unit is substituted with polyether Examples thereof include alkylaralkyl polyether-modified silicone oils such as a polymer of siloxane and phenylmethylsiloxane.

  Examples of the fatty acid include saturated or unsaturated fatty acids having 12 or more carbon atoms. Examples of fatty acids are lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, heptacosanoic acid, montanic acid, melicic acid , Laccelic acid, oleic acid, elaidic acid, linoleic acid, linolenic acid, arachidonic acid, cetreic acid, erucic acid and the like. The fatty acid is preferably a saturated fatty acid having 12 to 22 carbon atoms.

  Examples of the fatty acid ester include fatty acid esters of a fatty acid having 5 to 32 carbon atoms and a monovalent or polyhydric alcohol having 2 to 30 carbon atoms. As fatty acids, caproic acid, caprylic acid, undecylic acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, behenic acid, lignoceric acid, serotic acid, montanic acid, melicic acid and other saturated fatty acids, or oleic acid And unsaturated fatty acids such as elaidic acid, linoleic acid, linolenic acid, arachidonic acid, pladicic acid, erucic acid, ricinoleic acid and the like. Alcohols include monohydric alcohols such as propyl alcohol, isopropyl alcohol, butyl alcohol, octyl alcohol, capryl alcohol, lauryl alcohol, myristyl alcohol, stearyl alcohol, and behenyl alcohol, ethylene glycol, propylene glycol, butanediol, glycerin, pentaerythritol, sorbitan And other polyhydric alcohols. The fatty acid ester is preferably a fatty acid ester of a fatty acid having 12 to 22 carbon atoms and a monovalent or polyhydric alcohol having 2 to 22 carbon atoms.

  The fatty acid metal salt is a salt of a higher fatty acid and a metal, and examples of the higher fatty acid include stearic acid, oleic acid, octanoic acid, lauric acid, behenic acid, and ricinoleic acid. Examples of the metal include zinc, calcium, magnesium, nickel, copper and the like.

  The compounding amount of the release agent (D) is preferably 0.01 to 3 parts by mass, more preferably 0.05 to 2.5 parts by mass with respect to 100 parts by mass of the polyacetal resin. More preferably, it is ˜2 parts by mass. When the compounding amount of the release agent (D) is 0.01 to 3 parts by mass with respect to 100 parts by mass of the polyacetal resin, compared to when the compounding amount of the mold release agent (D) is less than 0.01 parts by mass. Thus, contamination of the mold during the molding process is more effectively suppressed. Moreover, compared with the case where the compounding quantity of a mold release agent (D) exceeds 3 mass parts, the mechanical characteristic of a polyacetal resin composition can be improved more.

(E) Anti-smudge stabilizer It is preferable that an anti-smudge stabilizer is further blended in the polyacetal resin composition of the present invention. In this case, generation of formaldehyde can be more effectively suppressed. As the anti-mold stabilizer, a light stabilizer or an ultraviolet absorber is preferably used. As the light stabilizer, hindered amine light stabilizers are preferably used, and those represented by the following general formula (5) are particularly preferably used.

In the above formula (5), R ⁶ is an organic group whose bond to the nitrogen atom is a carbon atom, X is an organic group bonded to the 4-position of the piperidyl group via an oxygen atom or nitrogen atom, or a hydrogen atom Represents.

Examples of R ⁶ include a linear or branched alkyl group having 1 to 10 carbon atoms. Examples of such an alkyl group include a methyl group, an ethyl group, a propyl group, a t-butyl group, a hexyl group, an octyl group, and a decyl group. Of these, a methyl group is preferred.

  Specific examples of preferred hindered amine light stabilizers include, for example, bis (1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, 1- [2- {3- (3,5-di-t- Butyl-4-hydroxyphenyl) propionyloxy} ethyl] -4- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] -2,2,6,6-tetramethylpiperidine, Tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate, 1,2,2,6,6-pentamethyl-4-piperidyl and tridecyl- 1,2,3,4-butanetetracarboxylate (part of four ester parts of butanetetracarboxylate is 1,2,2,6,6-pentamethyl-4-piperidyl A mixture of compounds in which the other is a tridecyl group), 1,2,3,4-butanetetracarboxylic acid, 1,2,2,6,6-pentamethyl-4-piperidinol and β, β, β, β-tetra Methyl-3,9 (2,4,8,10-tetraoxaspiro [5,5] udencan) -condensate with diethanol, dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl- 1-piperidineethanol condensate, 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate, N, N ′, N ″, N ″ ″-tetrakis- (4,6-bis- (butyl -(N-methyl-2,2,6,6-tetramethylpiperidin-4-yl) amino) -triazin-2-yl) -4,7-diazadecane-1,10-diamine, bis (1,2, 2,6,6-pentamethyl-4-pi Peridyl) [[3,5-bis (1,1 dimethylethyl) -4-hydroxyphenyl] methyl] butyl malonate.

  The said anti-stabilizer (E) may be blended singly or in combination of two or more. It is preferable that the compounding quantity of a weather-resistant stabilizer (E) is 0.01-3 mass parts with respect to 100 mass parts of polyacetal resin, It is more preferable that it is 0.03-2 mass parts, 0.05-1 More preferably, it is part by mass. In this case, the deterioration of the polyacetal resin composition is sufficiently suppressed as compared with the case where the blending amount of the anti-glare stabilizer (E) is less than 0.01 parts by mass. Moreover, compared with the case where the compounding quantity of a weather-resistant stabilizer (E) exceeds 3 mass parts, the mechanical characteristic of a polyacetal resin composition can be improved more.

  In addition to the above components (A) to (E), the polyacetal resin composition includes an antistatic agent such as an antioxidant, a coloring agent, a nucleating agent, a plasticizer, a fluorescent brightening agent, a sliding agent, polyethylene glycol, and glycerin. An additive such as an agent and a higher fatty acid salt may be further blended.

  In the polyacetal resin composition of the present invention, for example, the generation of formaldehyde is sufficiently suppressed. Therefore, as a countermeasure against so-called sick house syndrome, automobile interior parts, interior parts such as houses (hot water mixing plugs, etc.), clothing parts (fasteners) , Belt buckles, etc.), building material applications (piping, pump parts, etc.), machine parts (gears, etc.), fertilizers, resin compositions that require capture of carboxylic acid, and the like.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated more concretely, this invention is not limited to the following Example.

  The materials used in Examples and Comparative Examples are as follows.

(A) Polyacetal resin (POM)
An acetal copolymer obtained by copolymerizing trioxane and 1,3-dioxolane so that the content of 1,3-dioxolane in POM is 4.2% by mass, and having a melt index (ASTM-D1238) Standard: 190 ° C., 2.16 kg) is 10.5 g / 10 min. Acetal copolymer

Ｂ−２：下記式で表されるステアリン酸ヒドラジド２分子とヘキサメチレンジイソシアネート１分子の付加物

Ｂ−３：下記式で表されるラウリン酸ヒドラジド２分子とヘキサメチレンジイソシアネート１分子の付加物

Ｂ−４：下記式で表されるドデカン二酸ジヒドラジド１分子とイソシアン酸オクタデシル１分子の付加物

Ｂ−５：下記式で表されるアジピン酸ジヒドラジド１分子とイソシアン酸オクタデシル１分子の付加物

Ｂ−６：下記式で表されるイソフタル酸ジヒドラジド１分子とイソシアン酸オクタデシル１分子の付加物

Ｂ−７：下記式で表されるドデカン二酸ジヒドラジド１分子とイソシアン酸オクタデシル２分子の付加物

（Ｃ）熱安定剤
Ｃ−１（ヒンダードフェノール化合物）：商品名「イルガノックス２４５」、トリエチレングリコール−ビス［３−（３−ｔ−ブチル−５−メチル−４−ヒドロキシフェニル）プロピオネート］、ＢＡＳＦ社製
Ｃ−２（トリアジン化合物）：メラミン、三井化学社製 (B) Compound B-1: Adduct of stearic acid hydrazide and octadecyl isocyanate represented by the following formula

B-2: Adduct of 2 molecules of stearic acid hydrazide and 1 molecule of hexamethylene diisocyanate represented by the following formula

B-3: Adduct of two molecules of lauric hydrazide and one molecule of hexamethylene diisocyanate represented by the following formula

B-4: Adduct of one molecule of dodecanedioic acid dihydrazide and one molecule of octadecyl isocyanate represented by the following formula

B-5: Adduct of one molecule of adipic acid dihydrazide and one molecule of octadecyl isocyanate represented by the following formula

B-6: Adduct of one molecule of isophthalic acid dihydrazide and one molecule of octadecyl isocyanate represented by the following formula

B-7: Adduct of one molecule of dodecanedioic acid dihydrazide and two molecules of octadecyl isocyanate represented by the following formula

(C) Heat stabilizer C-1 (hindered phenol compound): trade name “Irganox 245”, triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate] , BASF C-2 (triazine compound): Melamine, Mitsui Chemicals

(D) Release agent Trade name "Kao wax EB-P", ethylenebisstearylamide, manufactured by Kao Corporation

(E) Anti-stabilizer Product name “Tinuvin 622”, 1- [2- (4-hydroxy-2,2,6,6-tetramethylpyridino) ethyl] butanedioic acid, manufactured by BASF

[Production of Compound (B)]
Each of the above compounds B-1 to 7 was produced as follows.
B-1
0.1 mol of stearic acid hydrazide and 400 g of N, N-dimethylacetamide were charged into a glass reactor, and the solution in the glass reactor was heated to 60 ° C. Next, 0.1 mol of octadecyl isocyanate was slowly dropped into the solution in the glass reactor to react stearic acid hydrazide with octadecyl isocyanate to obtain a reaction solution. Then, the reaction solution was cooled to precipitate crystals, and the precipitated crystals were filtered off, washed with methanol, and dried to obtain Compound B-1.
B-2
As the isocyanate compound, instead of octadecyl isocyanate, hexamethylene diisocyanate was used, and the compound was prepared in the same manner as compound B-1, except that 0.05 mol of hexamethylene diisocyanate was added dropwise to 0.1 mol of stearic acid hydrazide. B-2 was obtained.
B-3
Compound B-3 was obtained in the same manner as Compound B-2 except that lauric hydrazide was used instead of stearic acid hydrazide as a starting material.
B-4
Compound B-4 was obtained in the same manner as Compound B-1, except that dodecanedioic acid dihydrazide was used instead of stearic acid hydrazide as a starting material.
B-5
Compound B-5 was obtained in the same manner as Compound B-1, except that adipic acid dihydrazide was used instead of stearic acid hydrazide as a starting material.
B-6
Compound B-6 was obtained in the same manner as Compound B-1, except that isophthalic acid hydrazide was used instead of stearic acid hydrazide as a starting material.
B-7
Compound B-7 was obtained in the same manner as B-1, except that 0.2 mol of octadecyl isocyanate was added dropwise to 0.1 mol of dodecanedioic acid dihydrazide using dodecanedioic acid dihydrazide.
Of the above compounds B-1 to 7, for example, the B-3 and B-4 shows the measurement results of ¹ H-NMR spectrum in FIGS. Here, the ¹ H-NMR spectrum was performed using an NMR measuring apparatus (product name: AVANCE III, manufactured by Bruker BioSpin), and the measurement conditions were as follows.
Solvent used: trifluoroacetic acid Frequency: 500 MHz
Measurement temperature: room temperature, frequency was 500 MHz

[Production of polyacetal resin composition]
(Examples 1-14 and Comparative Examples 1-8)
Using a super mixer manufactured by Kawada Seisakusho Co., Ltd., with a blending ratio shown in Tables 1 to 3 of polyacetal resin (A), compound (B), heat stabilizer (C), mold release agent (D), and anti-mold stabilizer (E) And then uniformly kneading using a twin screw extruder (PCM-30 manufactured by Ikekai Tekko Co., Ltd., screw diameter 30 mm) according to a conventional method, after melt-kneading under the conditions of a screw rotation speed of 120 rpm and a cylinder set temperature of 190 ° C. The pellet of the polyacetal resin composition was manufactured by extruding to a strand and cutting with a pelletizer. In Tables 1 to 3, the unit of the blending amount is part by mass.

(Comparative Example 9)
The same as Example 1 except that 0.5 parts by mass of stearic acid hydrazide and hexamethylene diisocyanate were each compounded instead of 0.05 parts by mass of compound (B) per 100 parts by mass of polyacetal resin (A). The pellet of the polyacetal resin composition was manufactured by the method.

[Characteristic evaluation]
(1) Inhibitory effect of formaldehyde generation The inhibitory effect of formaldehyde generation was measured based on the amount of formaldehyde generated and measured.

The amount of formaldehyde generated was determined as follows.
<Fabrication of flat specimen>
First, pellets of the polyacetal resin compositions obtained in Examples 1 to 14 and Comparative Examples 1 to 9 were used at a cylinder temperature of 215 ° C. and a mold temperature of 80 ° C. using an injection molding machine PS-40 manufactured by Nissei Plastic Industry Co., Ltd. Injection molding was performed to prepare a 100 mm × 40 mm × 2 mm flat plate test piece.

<Measurement of formaldehyde generation>
On the day after the production of the flat test piece, the flat test piece was subjected to the following procedure in accordance with the method described in German Automobile Manufacturers Association Standard VDA275 (automobile interior parts-determination of formaldehyde emission by the revised flask method). The amount of formaldehyde generated was measured by the method described above.
(I) First, 50 ml of distilled water was put in a polyethylene container, the lid was closed with the flat plate test piece suspended in the air, and the container was heated at 60 ° C. for 3 hours in a sealed state.
(Ii) Subsequently, after leaving it to stand at room temperature for 60 minutes, a flat plate test piece was taken out.
(Iii) The amount of formaldehyde absorbed in distilled water in a polyethylene container was measured by an acetylacetone colorimetric method with a UV spectrometer, and the value obtained by dividing the amount of formaldehyde by the mass of POM in the flat plate test piece was the amount of formaldehyde generated It was. The results are shown in Tables 1-3.

In Tables 1 to 3, the pass / fail criteria for the formaldehyde generation suppression effect were as follows.
Formaldehyde generation amount is less than 4 μg / g-POM: Acceptable formaldehyde generation amount is 4 μg / g-POM or more: Fail

(2) Mold contamination suppression effect The mold contamination suppression effect was evaluated as follows. First, pellets of the polyacetal resin compositions obtained in Examples 1 to 14 and Comparative Examples 1 to 9 were molded using a so-called drop mold using a mini mat M8 / 7A molding machine manufactured by Sumitomo Heavy Industries, Ltd. 3000 shots were continuously formed at a temperature of 230 ° C. and a mold temperature of 35 ° C. After the molding, the state of the inner wall surface of the mold was observed with the naked eye. Here, the acceptance criteria regarding the mold contamination suppression effect were as follows.

A: Almost no mold deposits and very good mold contamination suppression effect B: Although there are some mold deposits, the mold contamination suppression effect is good C: Many mold deposits prevent mold contamination suppression effect Is bad

Here, A and B were accepted, and C was rejected. The results are shown in Tables 1-3.

  As shown in Tables 1 to 3, it was found that Examples 1 to 14 all met the acceptance criteria in terms of formaldehyde generation suppression and mold contamination suppression. On the other hand, it was found that all of Comparative Examples 1 to 9 did not satisfy the acceptance criteria in terms of formaldehyde generation amount or mold contamination suppression.

  Therefore, according to the polyacetal resin composition of this invention, it was confirmed that generation | occurrence | production of formaldehyde and contamination of the metal mold | die at the time of a shaping | molding process can fully be suppressed.

Claims (11)

(A) A polyacetal resin composition in which 0.05 to 5 parts by mass of a compound represented by the following formula (1) is blended with 100 parts by mass of a polyacetal resin.

(In the formula (1), m represents 0 or 1, n represents a positive integer. R ¹ is a (m + n) -valent group, an aliphatic hydrocarbon group having 1 to 40 carbon atoms, carbon A structural unit comprising an alicyclic hydrocarbon group having 3 to 40 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, a heterocyclic group having 2 to 5 carbon atoms, or —CZ ¹ Z ² —CZ ³ Z ⁴ — In the case where m = 1 and n = 1, R ¹ may be a single bond, and when m = 0 and n = 1, R ¹ is a hydrogen atom. respectively which may ^.Z 1 to Z ⁴ are independently a single bond, represents a hydrogen atom or an alkyl group having 1 to 10 carbon ^atoms, .R ² representative of at least one single bond of Z 1 to Z ⁴ are, A monovalent group, an aliphatic hydrocarbon group having 1 to 40 carbon atoms, an alicyclic hydrocarbon group having 3 to 40 carbon atoms, and an aromatic hydrocarbon group having 6 to 10 carbon atoms .Y represents a group represented by a heterocyclic group or the following formula 2 to 5 carbon atoms (1-A) represents a group represented by the following formula (1-B).)

In (Formula (1-A), ^{R 3} is a divalent group, aliphatic hydrocarbon group having 1 to 40 carbon atoms, alicyclic hydrocarbon group having 3 to 10 carbon atoms, 6 carbon atoms Represents an aromatic hydrocarbon group having 10 to 10 carbon atoms or a heterocyclic group having 2 to 5 carbon atoms, and R ⁴ is a monovalent group, an aliphatic hydrocarbon group having 1 to 40 carbon atoms, and 3 to 3 carbon atoms. 40 represents an alicyclic hydrocarbon group, an aromatic hydrocarbon group having 6 to 10 carbon atoms, or a heterocyclic group having 2 to 5 carbon atoms.)

  The polyacetal resin composition according to claim 1, wherein the compound represented by the formula (1) is an adduct of a hydrazide compound and an isocyanate compound. The polyacetal resin composition according to claim 1 or 2, wherein the compound represented by the formula (1) is at least one compound selected from the group consisting of compounds represented by the following general formulas (2) to (4). object.

(Wherein (2) ~ (4), ^{R 2} and ^{R 12} has the same meaning as ^{R 2} in the formula (1), the formula (4) may ^{.R 11} be the same as or different from each other in A monovalent group, a hydrogen atom, an aliphatic hydrocarbon group having 1 to 40 carbon atoms, an alicyclic hydrocarbon group having 3 to 40 carbon atoms, an aromatic hydrocarbon group having 6 to 10 carbon atoms, or carbon Represents a heterocyclic group having 2 to 5. R ²¹ is a divalent group, a single bond, an aliphatic hydrocarbon group having 1 to 40 carbon atoms, an alicyclic hydrocarbon group having 3 to 40 carbon atoms. Represents an aromatic hydrocarbon group having 6 to 10 carbon atoms or a heterocyclic group having 2 to 5 carbon atoms.) 4. The polyacetal resin composition according to claim 3, wherein in the formulas (2) to (4), R ² and R ¹² are each an aliphatic hydrocarbon group having 1 to 40 carbon atoms.   The polyacetal resin composition according to any one of claims 1 to 4, wherein 0.01 to 3 parts by mass of a heat stabilizer (C) is blended with 100 parts by mass of the polyacetal resin.   The polyacetal resin composition according to claim 5, wherein the heat stabilizer (C) is at least one heat stabilizer selected from the group consisting of a hindered phenol compound and a triazine compound.   The polyacetal resin composition as described in any one of Claims 1-6 by which 0.01-3 mass parts of mold release agents (D) are mix | blended with respect to 100 mass parts of said polyacetal resins.   The polyacetal resin composition according to claim 7, wherein the release agent (D) is at least one release agent selected from the group consisting of polyethylene, silicone oil, fatty acid, fatty acid ester, and fatty acid metal salt.   The polyacetal resin composition according to any one of claims 1 to 8, wherein 0.01 to 3 parts by mass of the anti-stabilizer (E) is blended with respect to 100 parts by mass of the polyacetal resin.   The polyacetal resin composition according to claim 9, wherein the weathering stabilizer (E) is at least one weathering stabilizer selected from the group consisting of a hindered amine light stabilizer and an ultraviolet absorber. The polyacetal resin composition according to claim 10, wherein the hindered amine light stabilizer is a hindered amine light stabilizer represented by the following general formula (5).

(In the formula (5), R ⁶ represents an organic group in which the bond to the nitrogen atom is a carbon atom, X represents an organic group or hydrogen atom that is bonded to the 4-position of the piperidyl group via an oxygen atom or a nitrogen atom. Represents.)

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