JPH08325430A - Polyacetal resin composition - Google Patents

Abstract

PURPOSE: To obtain a polyacetal resin composition which can give a molded article having an excellent balance between impact resistance and rigidity by incorporating a phenoxy resin into a blend of a polyacetal resin and a polyetheresteramide CONSTITUTION: This resin composition comprises 100 pts.wt. blend of (A) 60-95 wt.% polyacetal resin and (B) 40-5wt.% polyetheresteramide and (C) 1-30 pts.wt. phenoxy resin. The polyetheresteramide (B) is a copolymer derived from (a) a 20-48C polymerizable fatty acid, (b) azelaic acid and/or sebacic acid, (c) a 2-20C diamine, (d) a polyoxyalkylene glycol having a number - average mol.wt. of 200-3,000, and (e) a 6-20C dicarboxylic acid, and has an (a)/(b) ratio (by weight) of 0.3-5.0 and an (a+b+c)/(d+e) ratio (by weight) of 95/5 to 10/90. The composition can give a molded article having an excellent balance between impact resistance and rigidity, and is hence utilizable as a material in the fields of electronics, automobiles, OA apparatus, etc.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel polyacetal resin composition having improved impact resistance. More specifically, for example, electronics, automobiles,
The present invention relates to a polyacetal resin composition having excellent mechanical properties, particularly impact resistance, which is suitable as a material in the fields of OA equipment and home appliances.

[0002]

BACKGROUND OF THE INVENTION Polyacetal resins are used in many fields as engineering resins having excellent chemical properties such as mechanical properties, electrical properties and chemical resistance. However, its impact resistance is inferior to that of other engineering resins, so its application is limited. Various methods have been proposed to improve the impact resistance of the polyacetal resin. For example, Japanese Patent Publication No. 48-34830 proposes to improve impact resistance by adding a rubber elastic graft copolymer. On the other hand, the method of adding a polyether ester is disclosed in Japanese Patent Laid-Open No.
The method of adding a polyurethane elastomer in JP-A-2-85349 is disclosed in JP-A-59-155452 and 59-1.
It is proposed in Japanese Patent No. 45244. The method of adding polyetheresteramide is disclosed in JP-A-61-161.
It is proposed in Japanese Patent No. 183345. However,
The method disclosed in Japanese Patent Publication No. 48-34830 has a drawback that the rigidity of the polyacetal resin becomes too low due to the rubber component. In addition, JP-A-52-1
85249, 59-155452, 59-14524
According to the method disclosed in Japanese Patent No. 4,61-183345, the compatibility of the polyether ester, the polyurethane elastomer, the polyether ester amide and the polyacetal resin is insufficient, so that the impact resistance is not improved as expected. It has drawbacks.

[0003]

As a result of intensive studies to solve the above problems, polyacetal resin (60 to 95% by weight), polymerized fatty acid, azelaic acid and / or sebacic acid, diamine, polyoxyalkylene glycol and dicarboxylic acid are used. By mixing 1 to 30 parts by weight of a phenoxy resin with 100 parts by weight of a resin mixture composed of 40 to 5% by weight of polyether ester amide derived from an acid, a molded article having an excellent balance of impact resistance and rigidity can be obtained. It was found that a polyacetal resin composition that can be given is obtained, and the present invention has been completed based on this finding. That is, an object of the present invention is to obtain a polyacetal resin composition capable of giving a molded article having an excellent balance of impact resistance and rigidity, and the purpose thereof is (A) polyacetal resin 60 to 95. % By weight and (B) (a) polymerized fatty acid having 20 to 48 carbon atoms, (b)
Azelaic acid and / or sebacic acid, (c) diamine having 2 to 20 carbon atoms, (d) number average molecular weight of 200 to
3,000 polyoxyalkylene glycols, (e)
A copolymer derived from a dicarboxylic acid having 6 to 20 carbon atoms, wherein the weight ratio of (a) to (b) is (a).
/ (B) is 0.3 to 5.0, and [(a) + (b) +
The weight ratio of (c)] / [(d) + (e)] is 95/5 to 1
1/30 parts by weight of a phenoxy resin (C) is added to 100 parts by weight of a resin mixture consisting of 40 to 5% by weight of 0/90, which is transparent and has excellent flexibility and elastic recovery ability. Achieved by

The details of the present invention will be described below. The polyacetal resin used as the component (A) of the present invention may be an oxymethylene homopolymer or an oxymethylene copolymer. The oxymethylene homopolymer is composed of substantially oxymethylene units obtained by polymerizing formaldehyde, trioxane or tetraoxane.

Further, the oxymethylene copolymer has 15 oxyalkylene units having 2 to 8 adjacent carbon atoms in a chain consisting of oxymethylene units at random.
It is a copolymer having a structure introduced in an amount of not more than wt%. Oxyalkylene units include ethylene oxide, propylene oxide, epichlorohydrin, 1,3-dioxolane,
Derived from cyclic ethers such as glycol formal.

The polymerized fatty acid having 20 to 48 carbon atoms, which is used as the component (a) for deriving the polyether ester amide (B) of the present invention, is an unsaturated fatty acid such as dicarboxylic acid having 10 to 24 carbon atoms. A polymerized fatty acid obtained by polymerizing a monobasic fatty acid having one or more heavy or triple bonds is used. Specific examples thereof include dimers such as oleic acid, linoleic acid and erucic acid.

[0007] Commercially available polymerized fatty acids usually contain dimerized fatty acid as a main component and also contain raw material fatty acid and trimerized fatty acid, but the dimerized fatty acid content is 70% or more, It is preferably 95% by weight or more, and hydrogenated to reduce the degree of unsaturation. In particular, pre-pole 1009, pre-pole 1004, pre-pole 1010
Commercial products such as (above, manufactured by Unichema) and Enpol 1010 (manufactured by Henkel) are preferable. Of course, mixtures of these are also used.

The dicarboxylic acid (b) in the polyether ester amide (B) of the present invention is, for example, polymerizable, copolymerizable with a polymerized fatty acid, physical properties of the resulting polyether ester amide and compatibility with a polyacetal resin. From the point of view, mention may be made of azelaic acid, sebacic acid and mixtures of both.

Specific examples of the diamine (c) having 2 to 20 carbon atoms in the polyether ester amide (B) of the present invention include ethylenediamine, tetramethylenediamine, hexamethylenediamine, nonamethylenediamine and undecamethylene. Examples thereof include diamine, dodecamethylenediamine, 2,2,4-trimethylhexamethylenediamine, bis- (4-aminocyclohexyl) methane, bis- (3-methyl-4-aminocyclohexyl) methane and xylylenediamines.

Specific examples of the polyoxyalkylene glycol (d) for deriving the polyether ester amide (B) of the present invention include polyoxyethylene glycol, polyoxypropylene glycol, polyoxytetramethylene glycol and ethylene. Examples thereof include block or random copolymers of oxide and propylene oxide, block or random copolymers of ethylene oxide and tetrahydrofuran, and mixtures thereof. Polyoxytetramethylene glycol is preferably used because of the heat resistance, water resistance, mechanical strength, elastic recovery ability and the like of the obtained polyetheresteramide. The number average molecular weight of the polyoxyalkylene glycol used in the present invention needs to be in the range of 200 to 3000. When the number average molecular weight is less than 200, the melting point of the obtained polyether ester amide is low, and excellent physical properties cannot be obtained. Meanwhile, 3,
When it exceeds 000, in the block copolymerization step of the polyoxyalkylene glycol and the polyamide oligomer, the compatibility between the two decreases, coarse phase separation occurs, and uniform polycondensation cannot be performed. As a result, the molecular weight does not increase, and the transparency and mechanical strength of the obtained polyetheresteramide decrease, which is not preferable.

As the dicarboxylic acid (e) having 6 to 20 carbon atoms for deriving the polyether ester amide (B) of the present invention, specifically, adipic acid, azelaic acid, sebacic acid and dodecanedioic acid can be used. Aromatic dicarboxylic acids such as aliphatic dicarboxylic acids, terephthalic acid, isophthalic acid, diphenoxyethanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,2-cyclohexyl-4,
Examples thereof include alicyclic dicarboxylic acids such as 4'-dicarboxylic acid. In particular, dicarboxylic acids such as azelaic acid, sebacic acid, terephthalic acid, isophthalic acid and 1,4-cyclohexanedicarboxylic acid are preferable from the viewpoint of polymerizability and physical properties of polyetheresteramide.

The polyether ester amide (B) of the present invention comprises a polymerized fatty acid (a), azelaic acid and / or sebacic acid (b) and a diamine (c), and the weight of the polymerized fatty acid (a) relative to (b). Ratio (a) / (b) is 0.3-
The number average molecular weight was 5.0 and charged into a reaction vessel in which all three groups were sufficiently substituted with nitrogen so that all amino groups were substantially equivalent to all carboxyl groups and polycondensed at 170 ° C to 230 ° C. A polyamide oligomer of 500 to 5,000 is prepared, and a polyoxyalkylene glycol (d) having a number average molecular weight of 200 to 3,000 and a carbon number of 6 to
20 dicarboxylic acids (e), with all carboxyl groups being substantially equivalent to all hydroxyl groups, and [(a) +
The weight ratio of (b) + (c)] / [(d) + (e)] is 95.
/ 5 to 10/90, heated to 200 to 280 ° C. in the presence of a small amount of catalyst, reacted for 1 to 3 hours, and then reacted under reduced pressure of about 1 mmHg. In order to obtain the transparent, flexible and elastic recoverable polyetheresteramide of the present invention, a polymerized fatty acid (a) for azelaic acid and / or sebacic acid (b) is used.
It is necessary that the weight ratio (a) / (b) is 0.3 to 5.0 and the number average molecular weight of the polyamide oligomer is in the range of 500 to 5,000. When the weight ratio (a) / (b) is less than 0.3, the obtained polyetheresteramide has insufficient flexibility and elastic recovery ability. Further, in the block copolymerization step of the polyamide oligomer and polyoxyalkylene glycol, the compatibility between the two decreases, coarse phase separation occurs and uniform polycondensation cannot be performed,
The molecular weight does not increase, and the transparency and mechanical strength of the obtained polyetheresteramide decrease. (A) /
When (b) exceeds 5.0, the cohesive force of the hard segment decreases, and the mechanical strength and melting point of the polyether ester amide decrease. When the number average molecular weight of the polyamide oligomer is less than 500, the cohesive force of the hard segment decreases, and the mechanical strength and melting point of the polyetheresteramide decrease. On the other hand, when it is more than 5,000, in the block copolymerization step of the polyamide oligomer and the polyoxyalkylene glycol, both the number average molecular weight of the polyoxyalkylene glycol is too large and the content of the polymerized fatty acid is too small. The compatibility between them decreases, coarse phase separation occurs, homogeneous polycondensation cannot be performed, the molecular weight does not increase, and the transparency and mechanical strength of the obtained polyetheresteramide decrease.

The physical properties of the (B) polyetheresteramide of the present invention are as follows:
It is also influenced by the copolymerization ratio of the soft component [(d) + (e)] and the hard component [(a) + (b) + (c)] constituting the. The soft component [(d) + (e)] is 5 to 9
It is preferably 0% by weight. 5% by weight of soft ingredient
If it is less than 90% by weight, the flexibility and low-temperature properties of the obtained polyetheresteramide become insufficient, and conversely, if it exceeds 90% by weight, mechanical strength and melting point decrease, which is not preferable.

The phenoxy resin used as the component (C) of the present invention is a polycondensation product of epichlorohydrin and bisphenol A or a nuclear substitution product thereof, and has a structural unit represented by the following general formula (I). Consists of.

[0015]

Embedded image (In the formula, X _{1 to} X ₄ may be the same or different and each represents a hydrogen atom; a lower alkyl group such as a methyl group or an ethyl group; or a halogen atom such as chlorine or bromine.

The phenoxy resin preferably used in the present invention is derived from epichlorohydrin and bisphenol A and has a number average molecular weight of 10,000 to 75,000.
belongs to.

The proportion of the polyacetal resin (A) and the polyether ester amide (B) in the composition of the present invention must be 60 to 95% by weight of the polyacetal resin (A). When the blending ratio of the polyether ester amide is less than 5% by weight, the impact resistance of the polyacetal resin is insufficiently improved. On the other hand, if the blending ratio of the polyether ester amide exceeds 40% by weight, the rigidity and heat resistance are lowered and the properties of the polyacetal resin are impaired.

Further, in the composition of the present invention, (A)
It is necessary to add 1 to 30 parts by weight of the (C) phenoxy resin to 100 parts by weight of the resin mixture of the polyacetal resin and the (B) polyether ester amide.
When the amount of the phenoxy resin is less than 1 part by weight, the impact resistance is insufficiently improved, and when it exceeds 30 parts by weight, the rigidity is lowered, which is not preferable.

The composition of the present invention may optionally contain various additives such as antioxidants, heat stabilizers, plasticizers, UV inhibitors, lubricants, flame retardants, and fillers as long as the object of the present invention is not impaired. Additives such as agents and pigments, and reinforcing agents such as silica, carbon black, clay, glass beads, glass fibers, carbon fibers, organic fibers and calcium carbonate can be contained.

The method for preparing the resin composition of the present invention includes:
A melt kneading method is preferable, and a known method can be used as the melt kneading method. For example, it can be melt-kneaded using a Banbury mixer, a rubber roll machine, a single-screw or twin-screw extruder, etc. to obtain a resin composition.

The polyacetal resin composition of the present invention thus obtained is a known method generally used for molding thermoplastic resins, such as injection molding, extrusion molding,
It can be molded by a method such as blow molding or vacuum molding.

[0022]

The polyacetal resin composition of the present invention is
Since it is possible to provide a molded article having an excellent balance of impact resistance and rigidity, for example, electronics, automobiles, O
It is preferably used for various applications in the field of A equipment and the like.

[0023]

EXAMPLES The present invention will now be described in detail with reference to examples, but the present invention is not limited to these examples. Each property in the production examples and examples was measured by the following methods.

(1) Melt viscosity Using a flow tester CFT-500 manufactured by Shimadzu Corporation,
Measurement temperature 250 ℃, die 1mm (diameter) × 10mm (length), load 10k
It was measured under the condition of g.

(2) Acid Value and Amine Value The acid value was obtained by dissolving 1 g of the sample in 50 g of benzyl alcohol and using a phenolphthalein indicator in a methanol solution of 1/10 N NaOH. It was dissolved in 50 g of a 1/1 mixed solution and titrated with a 1/10 N hydrochloric acid methanol solution using a bromphenol blue indicator.

(3) Melting point and crystallization temperature Using a differential scanning calorimeter (DSC), the heating rate is 10 ° C. /
The melting point was measured at min, the temperature was lowered at 10 ° C./min, and the crystallization temperature was measured.

(4) Tensile strength and tensile elongation The shape has a total length (L) of 108 mm, a thickness (h) of 2.0 mm, a width (W) of 15 mm, a parallel portion length (C) of 50 mm, and a parallel portion width ( D) Tensile breaking strength and tensile breaking elongation were measured at a pulling speed of 2 mm / min in accordance with JIS K7113 using a test piece having a V-shaped notch with an angle of 30 ° at 10 mm and a depth of 3.0 mm.

(5) Izod impact strength The shape is a length (L) 64 mm × thickness (t) 2.5 mm × width (b) 12.7 mm with a tip radius of 0.25 mm and a depth of 2.5 mm. An Izod impact test was conducted according to JIS K7110 using a test piece having

<Synthesis of Polyether Esteramide> Production Example 1 Synthesis of TPAE-1 1000 ml of 4 equipped with a stirrer, nitrogen inlet and distillation tube
In the neck flask, the composition of the obtained polyamide copolymer,
By weight ratio, hexamethylenediamine-polymerized fatty acid polycondensate / hexamethylenediamine-azelaic acid polycondensate = 5
Hydrogenated type polymerized fatty acid (carbon number of 0/50)
36, product name Pripol 1009, manufactured by Unichema) 10
9.4 g, azelaic acid 81.4 g, and hexamethylene diamine 72.5 g were charged together with a 5% phosphorous acid aqueous solution 0.8 g, and the temperature was raised while flowing a constant amount of nitrogen, to obtain 158 ° C.
The water produced by the polycondensation reaction came out from the. The content at this time was a uniform transparent liquid. When the temperature was raised to 190 ° C., the contents were sampled, and the acid value and the amine value were adjusted so as to have an equivalent relationship. Finally, a transparent polyamide oligomer having a terminal group concentration of 41.2 mgKOH / g and a number average molecular weight of 1362 was obtained. Azelaic acid 5 at this temperature
When 6.9 g was added and the content became transparent, 206.4 g of polyoxytetramethylene glycol having a number average molecular weight of 341 and N, N'-hexamethylene-bis (3,5-
Di-t-butyl-4-hydroxycinnamic acid amide) (trade name Irganox 1098, antioxidant) 1.0 g were sequentially added, and when uniform, antimony trioxide was added.
1 g and 0.1 g of monobutylhydroxytin oxide were added. Then, the temperature was raised to 270 ° C. while allowing the water produced by the reaction to flow away, and this temperature was maintained for 30 minutes. Next, after reducing the pressure to 25 mmHg at this temperature and continuing the reaction for 30 minutes, 1
When the pressure was reduced to mmHg and the reaction was further advanced, 2 hours 30
Melt viscosity after 10 minutes 102.2 Pa · s / 250 ° C., melting point 1
Hard segment (polyamide copolymer) / soft segment (azelaic acid to polyoxytetramethylene glycol) = 50 / at 57.8 ° C. and crystallization temperature of 137.3 ° C.
50 (weight ratio) of transparent polyetheresteramide (TPAE-1) was obtained.

Production Example 2 Synthesis of TPAE-2 The composition of the polyether ester amide is hexamethylenediamine-polymerized fatty acid polycondensate / hexamethylenediamine-azelaic acid polycondensate = 70/30 and hard segment / soft segment = 20. The reaction was carried out according to Production Example 1 so that the ratio would be / 80 (weight ratio). 5 hours and 15 minutes after the start of depressurization, the melt viscosity is 76 Pa · s / 250.
C., a melting point of 109.degree. C., and a crystallization temperature of 77.degree. C. were obtained as a transparent polyetheresteramide (TPAE-2).

Production Example 3 Synthesis of TPAE-3 The composition of the polyether ester amide is 4,4'-diaminodicyclohexylmethane to polymerized fatty acid polycondensate / 4,
Production Example 1 so that 4′-diaminodicyclohexylmethane to azelaic acid polycondensate = 70/30 and hard segment / soft segment = 20/80 (weight ratio).
The reaction proceeded according to. 3 hours and 30 minutes after the start of depressurization, the melt viscosity is 110 Pa · s / 250 ° C. and the softening temperature is 10
Amorphous transparent polyetheresteramide (T
PAE-3) was obtained.

Production Example 4 Synthesis of TPAE-4 The composition of the polyether ester amide is 3,3'-dimethyl-4,4'-diamino-dicyclohexylmethane-polymerized fatty acid polycondensate / 3,3'-dimethyl-4. 4,4'-diamino-dicyclohexylmethane to azelaic acid polycondensate = 70/3
0 and hard segment / soft segment = 30/7
The reaction was carried out according to Production Example 1 so that the ratio became 0 (weight ratio). 1 hour and 30 minutes after the start of depressurization, the melt viscosity is 11
An amorphous, transparent polyetheresteramide (TPAE-4) having a temperature of 0 Pa · s / 250 ° C. and a softening temperature of 60 ° C. was obtained.

Examples 1 to 4 and Comparative Examples 1 to 5 Polyacetal resin (manufactured by Asahi Kasei Kogyo KK, Tenac 4
010), the polyether ester amides (TPAE-1 to 4) obtained in Production Example and a phenoxy resin (PKHH manufactured by Union Carbide Co., USA) were blended in the proportions shown in Table 1, and a 35 mmφ kneader ruder (Kasamatsu Kako) was used. (Manufactured by Kenkyusho) was melt-kneaded at 200 ° C. and pelletized. After drying the obtained pellets, a predetermined test piece was produced with an injection molding machine at a cylinder temperature of 210 ° C. and a mold temperature of 55 ° C. Using this test piece, the tensile strength, tensile elongation and notched Izod impact strength were measured, and the results are summarized in Table 1.

The parts by weight of the phenoxy resin are parts by weight based on 100 parts by weight of the resin mixture of the polyacetal resin and the polyether ester amide.

[0035]

[Table 1]

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[Procedure amendment]

[Submission date] July 11, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction content]

The dicarboxylic acid (e) having 6 to 20 carbon atoms for inducing the polyether ester amide (B) of the present invention is specifically adipic acid, azelaic acid, sebacic acid or dodecanedioic acid. Aromatic dicarboxylic acids such as aliphatic dicarboxylic acids, terephthalic acid, isophthalic acid, diphenoxyethanedicarboxylic acid, 1,4-
Examples thereof include alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. In particular, dicarboxylic acids such as azelaic acid, sebacic acid, terephthalic acid, isophthalic acid and 1,4-cyclohexanedicarboxylic acid are preferable from the viewpoint of polymerizability and physical properties of polyetheresteramide. ─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] September 29, 1995

[Procedure Amendment 1]

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[Correction target item name] 0035

[Correction method] Change

[Correction content]

[0035]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Toshie Kobayashi, Toshie Kobayashi, 253, Takemazawa, Miyoshi-cho, Iruma-gun, Saitama Prefecture 2 At Fuji Kasei Kogyo Co., Ltd. Technical Research Institute (72) Motohiro Fujimoto, Takeshi, Miyoshi-cho, Iruma-gun, Saitama Prefecture 2 at 253 Mazawa, Fuji Technology Co., Ltd., Technical Research Laboratory (72) Inventor, Kijuro Tashiro, 253 Takeshimazawa, Miyoshi-cho, Iruma-gun, Saitama 2 At Fuji Chemical Industry Co., Ltd. Technical Research Center

Claims (1)

[Claims] 1. A polyacetal resin (A) 60 to 95% by weight and (B) a polymerized fatty acid having 20 to 48 carbon atoms, (b) azelaic acid and / or sebacic acid,
A copolymer derived from (c) a diamine having 2 to 20 carbon atoms, (d) a polyoxyalkylene glycol having a number average molecular weight of 200 to 3,000, and (e) a dicarboxylic acid having a carbon number of 6 to 20. And (a) for (b) above
Of (a) / (b) is 0.3 to 5.0, and [(a) + (b) + (c)] / [(d) + (e)] is 95 / A polyacetal resin composition obtained by blending 1 to 30 parts by weight of a phenoxy resin (C) with 100 parts by weight of a resin mixture consisting of 40 to 5% by weight of a polyether ester amide of 5 to 10/90.