JPH06345938A - Polyoxymethylene resin composition and its production - Google Patents

Abstract

PURPOSE:To obtain the subject composition excellent in mold release, color tone and heat stability and also in hydrolysis resistance. CONSTITUTION:This resin composition comprises 100 pts. wt. polyoxymethylene resin, 0.001-20 pts. wt. full or partial ester of an organic acid with dipentaerythritol and/or tripentaerythritol, and 0.01-10 pts. wt. hindered phenolic compound of a molecular weight of 300 or above.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyoxymethylene resin composition having excellent releasability, color tone, heat stability and hydrolysis resistance, and a method for producing the same.

[0002]

2. Description of the Related Art Polyoxymethylene resins are known as engineering plastics having a good balance of mechanical strength and impact resistance, and are used in a wide range of fields as electronic equipment supplies and automobile parts. In recent years, polyoxymethylene resins are often used for parts used under severe conditions such as outdoors or under high temperature, and color tone stability at high temperatures and hydrolysis resistance are required. In addition, high mold releasability is required to improve mass productivity.

Since polyoxymethylene resin has poor thermal stability in structure, an antioxidant such as hindered phenol for imparting thermal stability and a formaldehyde scavenger for capturing formaldehyde generated by decomposition are indeed used. Formulations of various stabilizers have been devised.

For example, a resin composition prepared by blending a polyoxymethylene resin with an alkaline earth metal salt of a polyhydric alcohol monofatty acid ester and an ester of a tribasic inorganic acid, polyamides, and the like (Japanese Patent Laid-Open No. HEI-1) -204949) or a fatty acid ester of a polyhydric alcohol having an OH group such as stearic acid monoglyceride and polyethylene glycol (Japanese Patent Publication No. 56-52).
No. 940), or a resin composition further containing an organic acid metal salt (Japanese Patent Publication No. 62-14164), a resin obtained by mixing an ester of a polyhydric alcohol and a higher fatty acid, and a linear higher fatty acid amide. Composition (JP-A-63-2
No. 95661), and a resin composition (Japanese Patent Publication No. 28240/1990) in which a specific hindered phenol compound and pentaerythritol are mixed.

[0005]

However, the above-mentioned JP-A-1-204949 and JP-B-56-52940.
JP-B, JP-B-62-14164, JP-A-63-
The fatty acid esters of polyhydric alcohols and the like proposed in Japanese Patent No. 295661 are not sufficient for imparting thermal stability, releasability and hydrolysis resistance. Further, if a large amount of additive is added to impart sufficient characteristics, not only the color tone is impaired, but also problems such as bleed out of the additive and deterioration of mechanical strength occur. In addition, Japanese Patent Publication 2-28
The pentaerythritol disclosed in JP-A-240240 has a problem that it has a large sublimation property and a small effect on hydrolysis resistance. Therefore, an object of the present invention is to obtain a polyoxymethylene resin composition which is excellent in mold release property, color tone, thermal stability, and hydrolysis resistance.

[0006]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that a polyoxymethylene resin can be obtained by fully or partially esterifying an organic acid with dipentaerythritol and / or tripentaerythritol. It was found that a polyoxymethylene resin composition containing a hindered amine compound having a molecular weight of 300 or more has excellent releasability, color tone, thermal stability, and hydrolysis resistance. Arrived

That is, in the present invention, 0.001 to 20 parts by weight of a total or partial esterified product of (B) an organic acid and dipentaerythritol and / or tripentaerythritol is added to 100 parts by weight of (A) polyoxymethylene resin. And (C) 0.01 to 10 parts by weight of a hindered amine compound having a molecular weight of 300 or more, and a method for producing the same.

The polyoxymethylene resin (A) used in the present invention includes oxymethylene homopolymer, and
An oxymethylene copolymer mainly composed of oxymethylene units and containing at least one oxyalkylene unit having 2 to 8 carbon atoms in the polymer main chain can be mentioned.

As the oxymethylene homopolymer, a stable oxymethylene homopolymer obtained by substituting an unstable hydroxyl group at the terminal with an ester group or an ether group can be used. For example, substantially anhydrous formaldehyde is introduced into an organic solvent containing a basic polymerization catalyst such as an organic amine, an organic or inorganic tin compound, and a metal hydroxide to polymerize, and the polymer is filtered off. , In acetic anhydride,
Examples include those produced by heating in the presence of sodium acetate to acetylate the ends.

Examples of the oxymethylene copolymer include substantially anhydrous trioxane or a cyclic oligomer of formaldehyde such as tetraoxane and at least one cyclic ether or cyclic formal as a copolymerization component such as cyclohexane or benzene. After being dissolved or suspended in a simple organic solvent, the polymerization catalyst,
For example, at least one compound selected from the group consisting of boron trifluoride, boron trifluoride hydrate and a coordination compound of boron trifluoride and an organic compound containing an oxygen atom or a sulfur atom is added and polymerized. Those produced by decomposing and removing unstable ends can be used. Alternatively, bulk polymerization can be carried out by introducing the premixture of trioxane and the copolymerization component / catalyst into a self-cleaning stirrer without using any solvent. If desired, the polymer can be produced by washing the polymer to remove the catalyst, or deactivating the catalyst with a deactivator and then decomposing and removing the unstable terminal.

It is particularly preferred that trioxane and a cyclic ether or cyclic formal are bulk polymerized in the presence of a polymerization catalyst such as boron trifluoride / diethyl etherate, and then a hindered amine compound is added to carry out the polymerization reaction. Is a polyoxymethylene resin obtained by decomposing and removing unstable terminals.

The organic acid (B) used in the present invention and all or partial esterification products of dipentaerythritol and / or tripentaerythritol are acetic acid, butyric acid, caproic acid, caprylic acid, capric acid, lauric acid, myristic acid. , Palmitic acid, stearic acid, arachidic acid, 12
-Hydroxystearic acid, behenic acid, lignoceric acid, serotic acid, montanic acid, melissic acid, oleic acid, linoleic acid, ricinoleic acid, adipic acid, glutamic acid, sebacic acid, naphthenic acid, and dipentaerythritol and / or It is a total or partial esterification product of tripentaerythritol. Dipentaerythritol has a chemical formula of (HOCH ₂ ) ₃ CCH ₂ OCH ₂ C (C
H ₂ OH) ₃ . Further, tripentaerythritol has a chemical formula of (HOCH ₂ ) ₃ CCH ₂ OCH ₂ C (CH
₂ OH) ₂ CH ₂ OCH ₂ C (CH ₂ OH) ₃ .
As the organic acid, lauric acid, palmitic acid, stearic acid, 12-hydroxystearic acid, behenic acid, adipic acid and sebacic acid are preferable. The esterified product may be a total esterified product in which all hydroxyl groups are esterified, but a partially esterified product having at least one or more hydroxyl groups is preferable. Of these, a partially esterified product of adipic acid and dipentaerythritol, which has good compatibility with the polyoxymethylene resin, is preferable.

(B) The total or partial esterification product of organic acid and dipentaerythritol and / or tripentaerythritol is 100% by weight of polyoxymethylene resin 100.
0.001 to 20 parts by weight is necessary with respect to parts by weight, and preferably 0.01 to 5 parts by weight. If it is less than 0.001 part by weight, sufficient properties cannot be obtained, and if it is more than 20 parts by weight, the mechanical strength is deteriorated, which is not preferable.

The hindered phenolic compound (C) used in the present invention may have a molecular weight of 300 or more.
Specifically, 2,2'-methylene-bis (4-methyl-
6-t-butylphenol), triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3,5- Di-t-butyl-4-
Hydroxyphenyl) propionate], pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-
4-Hydroxyphenyl) propionate], N, N '
-Hexamethylenebis (3,5-di-t-butyl-4-
Hydroxyhydrocinnamamide), 2-t-butyl-6
-(3'-t-butyl-5'-methyl-2'-hydroxybenzyl) -4-methylphenyl acrylate, 3,
9-bis [2- {3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,
Examples thereof include 1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane. Among them, triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate], pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] are particularly preferred. Molecular weight is 30
When it is less than 0, the bleeding phenomenon is remarkable, the appearance of the polyoxymethylene resin composition is impaired, and the thermal stability is lowered, so that it cannot be used.

The addition amount is polyoxymethylene resin 1
0.01 to 10 parts by weight is necessary with respect to 00 parts by weight, and preferably 0.05 to 3.0 parts by weight.

When the (D) formaldehyde scavenger is used in the present invention, a polyamide compound, a urethane compound, a pyridine derivative, a pyrrolidone derivative, a urea derivative,
Triazine derivatives, hydrazine derivatives, amidine compounds, and polyacrylamide compounds can be used. Specifically, polyamide 6, polyamide 66, polyamide 6/6
6 binary copolymer, polyamide 6/66/610/12 quaternary copolymer, melamine, benzoguanamine, acetoguanamine, N-methylolmelamine, N, N'-dimethylolmelamine, N, N ', N'' -Trimethylol melamine, cyanoguanidine, polyacrylamide and the like are preferred. Among these, polyamide 6/66/610/12 quaternary copolymer, melamine, and benzoguanamine are particularly preferable. Polyamide 6/66/61 used in the present invention
The 0/12 quaternary copolymer is a copolymer obtained by copolymerizing a salt of a dicarboxylic acid and a diamine, an ω-aminocarboxylic acid or a lactam, and includes polyamide 6, polyamide 66, polyamide 610 and polyamide 12 A copolyamide having a structural unit consisting of The composition of this copolyamide can be various proportions, and in the present invention, it may be any proportion, but from the viewpoint of compatibility and dispersibility with the polyoxymethylene resin, this copolyamide usually has a melting point, The composition is in the range of 50 to 200 ° C, particularly preferably 80 to 170 ° C. The amount of these formaldehyde scavengers added is preferably 0.01 to 10 parts by weight, more preferably 0.01 to 3.0 parts by weight, based on 100 parts by weight of the polyoxymethylene resin.

When the (E) hindered amine compound is used in the present invention, a compound having a molecular weight of 300 or more can be used. Specifically, it is bis (2,2,6,6-tetramethyl-4-piperidyl). Sebacate, screw (1, 2, 2,
6,6-pentamethyl-4-piperidyl) sebacate,
Dimethyl succinate 1- (2-hydroxyethyl) -4
-Hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, N, N'-bis (3-aminopropyl) ethylenediamine-2,4-bis [N-butyl-N-
(1,2,2,6,6-pentamethyl-4-piperidyl) amino] -6-chloro-1,3,5-triazine condensate, poly [{6- (1,1,3,3-tetramethyl Butyl) amino-1,3,5-triazine-2,4-diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetra Methyl-4-piperidyl) imino}] and the like. Among these, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, dimethyl succinate.
-(2-hydroxyethyl) -4-hydroxy-2,
2,6,6-tetramethylpiperidine polycondensate, N,
N'-bis (3-aminopropyl) ethylenediamine
2,4-bis [N-butyl-N- (1,2,2,6,6
-Pentamethyl-4-piperidyl) amino] -6-chloro-1,3,5-triazine condensate, poly [{6-
(1,1,3,3-tetramethylbutyl) amino-1,
3,5-triazine-2,4-diyl} {(2,2,
6,6-Tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}] is particularly preferred. Molecular weight is 300
If it is smaller, the bleeding phenomenon is remarkable, the appearance of the polyoxymethylene resin composition is impaired, and the thermal stability is lowered, so that it cannot be used.

The addition amount is polyoxymethylene resin 1
0.01 to 10 parts by weight is preferable with respect to 00 parts by weight,
More preferably, it is 0.01 to 3.0 parts by weight.

When the alkaline earth metal salt of (F) fatty acid is used in the present invention, butyric acid, caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behen. Acids, lignoceric acid, cerotic acid, montanic acid, melissic acid, oleic acid, linoleic acid, ricinoleic acid, calcium salts such as 12-hydroxystearic acid, magnesium salts, strontium salts and barium salts can be used. Among these, calcium stearate, magnesium stearate, calcium behenate, magnesium behenate, 12-hydroxy calcium stearate and 12-hydroxy magnesium stearate are preferable. The amount added is preferably 0.01 to 10 parts by weight, more preferably 0.01 to 3.0 parts by weight, based on 100 parts by weight of the polyoxymethylene resin.

As a method for producing the polyoxymethylene resin composition of the present invention, a generally known method can be adopted. For example, a method of adding the stabilizer used in the present invention in the polymerization or stabilization step of the polyoxymethylene resin, the polyoxymethylene resin and the stabilizer used in the present invention in pellet form,
It may be mixed in powder or granular form and melt-processed as it is, but a method of melt-mixing with a Banbury mixer, a roll, an extruder or the like can also be adopted. Further, a method of melt-kneading the stabilizer used in the present invention with a generally commercially available polyoxymethylene resin in the same manner as described above can also be adopted. In particular, using a single-screw or twin-screw extruder,
A method of melt mixing at a temperature of ˜250 ° C. is preferable.

The whole or partial esterified product of the organic acid (B) and dipentaerythritol and / or tripentaerythritol of the present invention is deactivated by polymerizing a mixture of trioxane and a cyclic ether in the presence of a polymerization catalyst. If it is added later when heating to remove unstable ends, the stabilization time can be shortened. The heating temperature for removing the unstable terminal is preferably 100 to 270 ° C. Further, at this time, it is preferable to add (C) a hindered phenol compound having a molecular weight of 300 or more.

Particularly preferably, a mixture of trioxane and a cyclic ether is selected from the group consisting of boron trifluoride, boron trifluoride hydrate, and a coordination compound of boron trifluoride and an organic compound containing an oxygen atom or a sulfur atom. In the presence of at least one polymerization catalyst selected from the following, bulk polymerization is carried out to produce an oxymethylene copolymer containing an oxymethylene unit and another oxyalkylene unit, and after the completion of the polymerization, (D) a hindered amine compound having a molecular weight of 300 or more is added. To deactivate the boron trifluoride-based catalyst,
(B) a total or partial esterification product of an organic acid and dipentaerythritol and / or tripentaerythritol,
(C) A hindered phenolic compound having a molecular weight of 300 or more and (E) a formaldehyde scavenger of 0.01 to 10 parts by weight are added and heated at a temperature range of 100 to 270 ° C. to remove unstable terminals. To be

In the resin composition of the present invention, calcium carbonate, barium sulfate,
Clay, titanium oxide, silicon oxide, mica powder, filler such as glass beads, carbon fiber, glass fiber, ceramic fiber, aramid fiber, reinforcing agent such as potassium titanate fiber, colorant (pigment, dye), nucleus Agents, plasticizers, release agents such as ethylene bisstearamide, polyethylene wax, conductive agents such as carbon black, thioether compounds, antioxidants such as phosphite compounds, benzophenone compounds, benzotriazole compounds Additives such as light stabilizers such as compounds, adhesives, polyhydric alcohols, fatty acid esters, lubricants such as metal soaps, hydrolysis resistance improvers, adhesion aids, etc. can be optionally contained.

The polyoxymethylene resin obtained by the present invention is used for sensors, LED lamps, connectors, sockets, resistors, relay cases, switches, coil hobbins,
Condenser, Varicon case, Optical pickup, Transmitter, Various terminal boards, Transformer, Plug, Print board, Tuner, Speaker, Microphone, Headphone,
Small motor, magnetic head base, power module,
It is preferably used for electric / electronic parts such as semiconductors, liquid crystals, FDD carriages, FDD chassis, magnetic tape cassette reels, motor brush holders, parabolic antennas, computer-related parts, etc., but other uses such as VTR parts, VTRs. Camera parts, TV parts, irons, hair dryers, shavers, fans, juicers, rice cooker parts, microwave oven parts, headphone stereos, radio-cassettes, audio / laser disks, compact disks, and other audio equipment parts, lighting parts, refrigerator parts, air conditioners. Parts, typewriter parts,
Household such as calculators and word processor parts, office electrical product parts, office computer related parts, telephone related parts, facsimile related parts, copier related parts, cleaning jigs, motor parts, lighters, typewriters, etc. Mechanical parts, microscope, binoculars,
Optical equipment typified by cameras and watches, precision machinery-related parts, alternator terminals, alternator connectors, IC regulators, potentiometer bases for light deer, various valves such as exhaust gas valves, various fuel-related, exhaust systems, intake systems Pipe, air intake nozzle snorkel, intake manifold, fuel pump, engine cooling water joint, carburetor main body, carburetor spacer, exhaust gas sensor,
Cooling water sensor, hot water sensor, brake pad wear sensor, throttle position sensor, crankshaft position sensor, air flow meter, brake pad wear sensor, air conditioner thermostat base, heating hot air flow control valve, radiator motor brush holder, water Pump impeller, turbine vane, wiper motor related parts, detributor, starter switch, starter relay, transmission wiring harness, air conditioner panel switch board, fuel related electromagnetic valve coil, fuse connector, horn terminal, electrical component insulating plate, Step motor rotor, lamp socket, lamp reflector, lamp housing, brake piston, soleno Dohobin, engine oil filter, radiator drain cock, in-tank fuel pump, diaphragm valve, auto antenna gear case, door lock, turn signal switch, wiper gear,
Wiper pivot bearing, speedometer gear,
Parts, housing, window glass bottom channel, seat belt housing, seat belt retractor parts, heater control lever, inside door handle, regulator handle, outer door handle, sun visor bracket, collapsible room mirror stay, seat hook, fender mirror case , Fuel caps, window washer nozzles, automobile / vehicle related parts such as ignition devices, bicycles, lawn mowers, partition corner pieces, curtain liners, blind gears, door wheels, office furniture parts, various fasteners, piping systems, hose joints, valves, Bindings, adjustments, various fasteners, meters, shoe parts, toys, music boxes, beauty parts such as combs, caster brackets, rollers , Cap ,, major parts,
It can also be used for lighters, aerosol bottles, sports equipment, and other various general equipment parts.

Examples will be described below, but the present invention is not limited thereto.

[0026]

The present invention will be described below with reference to examples. All percentages and parts in the examples are by weight.

Further, the mechanical properties, color tone, thermal stability of polymer, releasability and hydrolysis resistance of the molded products shown in Examples and Comparative Examples were measured as follows.

Molding: Using an injection molding machine having a mold clamping pressure of 60 t, a cylinder temperature of 190 ° C., a mold temperature of 80 ° C. and a molding cycle of 20 seconds were set, and an ASTM No. 1 dumbbell test piece was injection molded.

Color tone: ASTM obtained by the above injection molding
No. 1 dumbbell test piece YI (yellow index)
The value was measured by the SM color computer (Suga Tester).

Mechanical properties: AS obtained by the above injection molding
Using the TM1 dumbbell test piece, ASTM D-638
The tensile strength was measured according to the method.

Thermal stability of polymer: 10.0 g pellets
Put it in a container made of aluminum foil and put it in an oven at 240 ° C for 1
It was melted and retained for an hour. After the test, the weight and color tone (YI value) of the sample solidified at room temperature were measured.

Releasability: An injection molding machine having a mold clamping pressure of 60 t was used to set a cylinder temperature of 190 ° C. and a mold temperature of 30 ° C. to injection-mold a small box for mold releasability test. The releasing force was measured to judge the releasability.

Hydrolysis resistance: ASTM No. 1 dumbbell test pieces obtained by the above injection molding were enclosed in a pressure-resistant cylinder together with pure water and kept at 120 ° C. After 15 days, the test piece was taken out, and the tensile strength was measured according to the ASTM D-638 method.

Example 1 A twin-screw extruder type polymerization machine (100 mmφ, cylinder length (L) / cylinder diameter (D) = 10.2) was added to trioxane (30 kg / h) and 1,3-dioxolane (1150).
g / h), and as a catalyst for trioxane 12
0 ppm of boron trifluoride / diethyl etherate (2.5% benzene solution), 733 as molecular weight regulator
Each of ppm methylal was supplied to carry out continuous polymerization. Polymerization controls the outer jacket to 58 ℃,
The rotation speed was 40 rpm. Methylal was dissolved in trioxane. Further, a premixing zone was provided so that 1,3-dioxolane and the catalyst solution were premixed immediately before being supplied to the polymerization machine. The polymer was 28. as a fine white powder.
Obtained at 3 kg / h.

To 5 kg of the fine powder thus obtained, 9.0 ml of "Sanol" LS765 [Sankyo, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate] was added in an amount of 50 ml. The solution dissolved in benzene was added and stirred in a Henschel mixer for 3 minutes to deactivate the catalyst.

To 100 g of this deactivated polymer,
Irganox "245 [Ciba Geigy, triethylene glycol-bis {3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate}] 0.5
g, "Plenizer" ST-210 [Ajinomoto, partial esterification product of adipic acid and dipentaerythritol]
After adding 0.3 g and mixing, it is put into a 100 cc mixer (Labo Plastomill manufactured by Toyo Seiki) at 210 ° C., and 50
Kneading was carried out for 20 minutes at rpm. Unstable ends are decomposed and HC
After the HO gas is generated and violently foams, the torque becomes stable,
It became a transparent molten state.

Comparative Example 1 The procedure of Example 1 was repeated without adding "Plenizer" ST-210. Foaming did not stop even after kneading for 20 minutes, the torque was greatly reduced, and a strong HCHO odor was produced.

Example 2 In Example 1, the polymerization catalyst which had been subjected to catalyst deactivation was added to "Irganox" 1010 [Ciba Geigy, pentaerythrityl-tetrakis {3- (3,5-di-t-butyl-4-]].
Hydroxyphenyl) propionate}] 0.5 g, "
Plane riser "ST-2100.3g, polyamide 6
/ 66/610/12 quaternary copolymer (copolymerization composition 6/6
6/610/12 = 22/16/12/50 (wt
%)) 0.1 g was added and mixed, and then 100 ° C. at 210 ° C.
The mixture was put into a cc mixer (Labo Plastomill manufactured by Toyo Seiki) and kneaded at 50 rpm for 15 minutes. The unstable terminal was decomposed, HCHO gas was generated, and after vigorous foaming, the torque was stable and a transparent molten state was obtained.

Comparative Example 2 The procedure of Example 2 was repeated without adding "Plenizer" ST-210. Foaming did not stop even after kneading for 20 minutes, the torque was greatly reduced, and a strong HCHO odor was produced.

Examples 3 to 11 and Comparative Examples 3 to 7 To 5 kg of the fine powder of Example 1, the benzene solution of the (E) hindered amine compound shown in Table 1 was added to deactivate the catalyst. (E) After adding the stabilizers shown in Table 1 excluding hindered amine compounds, with a vent 40 m
Polymer was obtained by heating and melting at 230 ° C./10 mmtorr using an mφ twin-screw extruder. The resulting polymer was extruded as strands and pelletized by a cutter. The pellets were dried in a hot air circulation oven at 80 ° C. for 3 hours, then molded, and subjected to measurement of mechanical properties and hydrolysis resistance test. In addition, molding was performed separately, and the releasability was evaluated.

Further, the dried pellets were used to evaluate the thermal stability of the polymer. The results are summarized in Table 2.

Example 12 Commercially available oxymethylene copolymer (polyplastics ")
0.1 parts by weight of "Plenizer" ST-210 and 0.1 parts by weight of "Irganox" 1010 were added to 100 parts by weight of DURACON "M90), and a twin-screw 45 mmφ extruder with a vent made by Ikegai Iron Works was used. 210 ° C / 10
Melt extrusion kneading was performed at mm torr. It evaluated similarly to Examples 3-11. The results are shown in Table 3.

Comparative Example 8 In Example 12, "Plenizer" ST-210,
And "Irganox" 1010 was not added. The results are shown in Table 3.

(B) All or partial esterification products of organic acid and dipentaerythritol used in Examples and Comparative Examples,
The whole or partial esterification product of tripentaerythritol, (C) hindered phenol compound, (D) formaldehyde scavenger, (E) hindered amine compound, and (F) fatty acid alkaline earth metal salt are as follows.

(B) Full or partial esterification product of organic acid and dipentaerythritol, full or partial esterification product of tripentaerythritol. B-1: Partial esterification product of adipic acid and dipentaerythritol (Ajinomoto "Plenizer" ST). -21
0) -B-2: Monoesterification product of stearic acid and dipentaerythritol-B-3: Diesterification product of stearic acid and dipentaerythritol-B-4: 12-hydroxystearic acid monoesterification product of tripentaerythritol- B-5: Monoesterified product of stearic acid and pentaerythritol. B-6: Monoesterified product of stearic acid and glycerin (C) Hindered phenol compound. C-1: Triethylene glycol-bis [3- (3-
t-butyl-5-methyl-4-hydroxyphenyl) propionate] (Ciba Geigy “Irganox” 24
5) C-2: 1,6-hexanediol-bis [3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate] (Ciba Geigy "Irganox" 2
59) C-3: pentaerythrityl-tetrakis [3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate] (Ciba Geigy "Irganox" 1
010) (D) Formaldehyde scavenger D-1: Polyamide 6/66/610/12 quaternary copolymer (copolymerization composition 6/66/610/12 = 22/16
TH / 12: Polyamide 6/66/610/12 quaternary copolymer (copolymerization composition 6/66/610/12 = 33/1)
7/33/17 (wt%))-D-3: melamine-D-4: benzoguanamine (E) hindered amine compound-E-1: bis (1,2,2,6,6-pentamethyl-
4-piperidyl) sebacate (Sankyo "Sanol" LS7
65) E-2: dimethyl succinate. 1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate (Ciba Geigy "Tinuvin" 62
2LD) -E-3: N, N'-bis (3-aminopropyl) ethylenediamine-2,4-bis [N-butyl-N- (1,
2,2,6,6-Pentamethyl-4-piperidyl) amino] -6-chloro-1,3,5-triazine condensate (Ciba Geigy “Cimasorb” 119FL) E-4: poly [{6- (1, 1,3,3-Tetramethylbutyl) amino-1,3,5-triazine-2,4-
Diyl} {2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino)}] (Ciba Geigy "Kimasorb" 944FL) (F) Alkaline earth metal salt of fatty acid-F-1: 12-hydroxy calcium stearate-F-2: calcium stearate-F-3: magnesium behenate

[Table 1]

[0046]

[Table 2]

[0047]

[Table 3]

(A) Polyoxymethylene resin (B) Organic acid and dipentaerythritol and / or tripentaerythritol in total or partial esterified form, and
(C) a hindered phenol compound having a molecular weight of 300 or more, or (D) a formaldehyde scavenger,
(E) a hindered amine compound having a molecular weight of 300 or more,
(F) The one to which the alkaline earth metal salt of fatty acid is added,
Excellent initial color tone and 24
The weight loss and color change at 0 ° C for 1 hour are small, the releasing force is also small, and the strength retention rate in the hydrolysis resistance test after 120 ° C for 15 days is excellent.

From these results, it is clear that the polyoxymethylene resin composition of the present invention has excellent releasability, color tone, thermal stability and hydrolysis resistance.

[0050]

The polyoxymethylene resin composition of the present invention is excellent in releasability, color tone, thermal stability, and hydrolysis resistance. Therefore, in addition to excellent color tone, thermal stability, and hydrolysis resistance, it also has excellent releasability, which makes molding extremely easy, and is widely used as a mechanical mechanism component in the electrical / electronic field, automobile field, etc. Can be used for

Claims (13)

[Claims] 1. 0.001 to 20 parts by weight of a total or partial esterified product of (B) an organic acid and dipentaerythritol and / or tripentaerythritol per 100 parts by weight of (A) polyoxymethylene resin, and (C ) Hindered phenolic compounds having a molecular weight of 300 or more 0.01
A polyoxymethylene resin composition containing 10 to 10 parts by weight. 2. 0.001 to 20 parts by weight of a total or partial esterified product of (B) an organic acid and dipentaerythritol and / or tripentaerythritol, relative to 100 parts by weight of (A) polyoxymethylene resin, (C). Molecular weight 30
0 or more hindered phenolic compounds 0.01 to 10
Parts by weight, and (D) formaldehyde scavenger 0.01
A polyoxymethylene resin composition containing 10 to 10 parts by weight. 3. The (B) organic acid and all or a partial esterification product of dipentaerythritol and / or tripentaerythritol is lauric acid, palmitic acid, stearic acid, 12-hydroxystearic acid, behenic acid, adipic acid, sebacic acid. The polyoxymethylene resin composition according to claim 1, which is a partial esterified product of one or more organic acids selected from dipentaerythritol and / or tripentaerythritol. 4. The polyoxymethylene resin composition according to claim 1, wherein the whole or partial esterification product of (B) an organic acid and dipentaerythritol and / or tripentaerythritol is a partial esterification product of adipic acid and dipentaerythritol. . 5. The (C) hindered phenol compound having a molecular weight of 300 or more is triethylene glycol-bis [3].
-(3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-
From bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] The polyoxymethylene resin composition according to claim 1, which is one or more selected compounds. 6. The polyoxymethylene resin composition according to claim 2, wherein the formaldehyde scavenger (D) is one or more compounds selected from polyamide, melamine, benzoguanamine, cyanoguanidine and polyacrylamide. 7. The polyoxymethylene resin composition according to claim 2, wherein the formaldehyde scavenger (D) is a polyamide 6/66/610/12 quaternary copolymer. 8. (A) 0.001 to 20 parts by weight of (B) an organic acid and dipentaerythritol and / or tripentaerythritol in total or partial esterified product relative to 100 parts by weight of (A) polyoxymethylene resin, (C) Molecular weight 30
0 or more hindered phenolic compounds 0.01 to 10
Parts by weight, (D) formaldehyde scavenger 0.01 to 10
A polyoxymethylene resin composition comprising (parts by weight) and (E) 0.01 to 10 parts by weight of a hindered amine compound having a molecular weight of 300 or more. 9. (E) The hindered amine compound having a molecular weight of 300 or more is bis (2,2,6,6-tetramethyl-
4-piperidyl) sebacate, bis (1, 2, 2, 6,
6-pentamethyl-4-piperidyl) sebacate, dimethyl succinate-1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, N, N'-bis (3 -Aminopropyl) ethylenediamine-2,4-bis [N-butyl-N- (1,
2,2,6,6-Pentamethyl-4-piperidyl) amino] -6-chloro-1,3,5-triazine condensate, poly [{6- (1,1,3,3-tetramethylbutyl) amino] -1,3,5-triazine-2,4-diyl}
{(2,2,6,6-tetramethyl-4-piperidyl)
The polyoxymethylene resin composition according to claim 8, which is one or more compounds selected from imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}]. 10. (A) Polyoxymethylene resin 100
0.001 to 20 parts by weight of a total or partial esterification product of (B) an organic acid and dipentaerythritol and / or tripentaerythritol, (C) a molecular weight of 4 with respect to parts by weight.
00 or more hindered phenolic compound 0.01 to 1
0 parts by weight, (D) 0.01 to 10 parts by weight of a hindered amine compound having a molecular weight of 400 or more, (E) 0.01 to 10 parts by weight of a formaldehyde scavenger, and (F) 0.01 of an alkaline earth metal salt of a fatty acid. A polyoxymethylene resin composition containing 10 to 10 parts by weight. 11. (F) The alkaline earth metal salt of a fatty acid is calcium stearate, magnesium stearate,
The polyoxymethylene resin composition according to claim 10, which is one or more compounds selected from calcium behenate, magnesium behenate, calcium 12-hydroxystearate and magnesium 12-hydroxystearate. 12. A mixture of (A) trioxane and a cyclic ether or cyclic formal is polymerized in the presence of a polymerization catalyst to deactivate the catalyst, and then (B) relative to 100 parts by weight of the obtained polyoxymethylene resin. 0.001 to 20 parts by weight of a total or partial esterification product of an organic acid and dipentaerythritol and / or tripentaerythritol, and (C) 0.01 to 10 parts by weight of a hindered phenol compound having a molecular weight of 300 or more are added, 100-270 ° C
A method for producing a polyoxymethylene resin composition, characterized in that the unstable terminal is removed by heating in the temperature range of 1. 13. A mixture of (A) trioxane and a cyclic ether or cyclic formal, with boron trifluoride, boron trifluoride hydrate, and coordination between boron trifluoride and an organic compound containing an oxygen atom or a sulfur atom. In the presence of at least one polymerization catalyst selected from the group consisting of compounds, in bulk polymerization to produce a polyoxymethylene resin containing oxymethylene units and other oxyalkylene units,
After completion of the polymerization, 0.01 to 10 parts by weight of (E) a hindered amine compound having a molecular weight of 300 or more is added to 100 parts by weight of the polyoxymethylene resin to deactivate the boron trifluoride-based catalyst, and the polyoxymethylene resin is further added. 0.001 to 20 parts by weight of a total or partial esterified product of (B) organic acid and dipentaerythritol and / or tripentaerythritol per 100 parts by weight, (C) molecular weight 300
0.01 to 10 parts by weight of the above hindered phenol compound, and (D) formaldehyde scavenger 0.01 to
A method for producing a polyoxymethylene resin composition, which comprises adding 10 parts by weight and heating the mixture in a temperature range of 100 to 270 ° C. to remove unstable terminals.