KR102455022B1 - Polyoxymethylene Resins Composition and Molding produced from the same - Google Patents

Abstract

The present invention relates to a polyoxymethylene resin composition and a molded article prepared therefrom.
It is characterized in that it comprises the polyoxymethylene resin, methyl methacrylate-butadiene-styrene rubber and polyurethane styrene composite diene block copolymer.
The polyoxymethylene resin composition of the present invention may have excellent room temperature impact resistance and low temperature impact resistance along with excellent mechanical properties. In addition, the molded article prepared from the polyoxymethylene resin composition according to the present invention has excellent impact resistance, thereby preventing the molded article from breaking.

Description

Polyoxymethylene Resins Composition and Molding produced from the same}

The present invention relates to a polyoxymethylene resin composition and a molded article prepared therefrom.

Polyoxymethylene resin is an engineering plastic used in various fields such as electric and electronic parts and automobiles because of its excellent mechanical properties, rigidity, chemical resistance, and long-term durability. When the polyoxymethylene resin is used to manufacture parts such as clips or fasteners, excellent elongation at break, room temperature impact resistance, and low temperature impact resistance are required. However, since the polyoxymethylene resin has a very high degree of crystallinity and is hard, when cracks occur due to an impact applied to a molded article made of the resin, the propagation speed thereof is very fast, so it is easy to break. Therefore, research on adding various reinforcing agents as a method to improve the elongation at break, room temperature impact resistance, and low temperature impact resistance has been conducted before, and is still being actively conducted.

As a method for improving the impact resistance of polyoxymethylene, a method of adding a thermoplastic polyurethane having a glass transition temperature of -15°C or less (see U.S. Patent No. 5041505), a method for improving elongation at break and impact resistance A method of adding a reinforcing agent and a coupling agent (see US Patent No. 5043398, US Patent Publication No. 2007-0276064), a method for improving elongation at break and impact resistance at room temperature, and improving extrusion processability of the resin and thermoplastic polyurethane Method of adding a compound containing a polyethylene maleic anhydride group modified with A method of adding methyl methacrylate-butadiene-styrene and an isocyanate compound together to improve impact resistance properties (Korean Patent Application Laid-Open No. 2017-0051697) has been proposed.

However, in the case of the prior art, since an isocyanate compound is added to improve elongation at break, yellowing is likely to occur during post-processing (injection or extrusion). In addition, there is a limit in securing room temperature impact strength and low temperature impact strength, so it is impossible to apply because cracking occurs when applied to ski boot binders, gears, toys, etc., and applicable products are limited.

Accordingly, there is a need to develop a technology for a composition having excellent mechanical properties and, at the same time, excellent room temperature impact resistance and low temperature impact resistance.

The present invention provides a polyoxymethylene resin composition that has superior tensile strength and flexural strength than conventional polyoxymethylene resins, and in particular, has excellent room temperature impact resistance and low temperature impact resistance properties to prevent cracking in applied products, and from the same. To provide a manufactured molded article.

In order to achieve the above object, the present invention is a preferred embodiment,

Provided is a polyoxymethylene resin composition comprising a polyoxymethylene resin, a methyl methacrylate-butadiene-styrene rubber, and a polyurethane styrene composite diene block copolymer.

The polyoxymethylene resin composition comprises 3 to 6 parts by weight of methyl methacrylate-butadiene-styrene rubber and 0.5 to 8 parts by weight of a polyurethane styrene composite diene block copolymer based on 100 parts by weight of the polyoxymethylene resin. It may be characterized by including.

The polyurethane styrene composite diene block copolymer comprises (i) a thermoplastic polyurethane and (ii) a thermoplastic elastomer, wherein the thermoplastic elastomer comprises an aromatic vinyl compound polymer block and a conjugated diene compound polymer block. can do.

The polyurethane styrene composite diene block copolymer may be characterized in that the mass ratio of (i) thermoplastic polyurethane and (ii) thermoplastic elastomer is 80:20 to 20:80.

The weight average molecular weight of the polyurethane styrene composite diene block copolymer may be 30,000 to 300,000 g/mol.

The polyurethane styrene composite diene block copolymer may have a shore A hardness of 75 to 85, and (i) a shore A hardness of the thermoplastic polyurethane of 70 to 75.

The polyurethane styrene composite diene block copolymer may have a glass transition temperature of -40 to -30°C.

The methyl methacrylate-butadiene-styrene rubber may have a core-shell structure including a core formed of butadiene-styrene rubber and a shell formed of methyl methacrylate.

The polyoxymethylene resin composition further comprises 20 to 30 parts by weight of a thermoplastic polyurethane, 4 to 7 parts by weight of an ethylene acrylate copolymer, and 4 to 7 parts by weight of a polyether-ester block copolymer based on 100 parts by weight of the polyoxymethylene resin. It may be characterized by including.

The ethylene acrylate copolymer may be characterized in that it is a compound represented by the following formula (1).

<Formula 1>

(Wherein, R ₁ is an alkyl group having 1 to 3 carbon atoms, x is an integer of 60 to 130, and y is an integer of 10 to 20.)

The ethylene acrylate copolymer may be characterized in that the mass ratio of the ethylene polymer to the acrylate polymer in the ethylene acrylate copolymer is 85:15 to 70:30.

The polyether-ester block copolymer may be characterized in that a mass ratio of a soft segment to a hard segment in the polyether-ester block copolymer is 68:32 to 40:60.

The polyether-ester block copolymer may have a shore D hardness of 28 to 55.

As another preferred embodiment according to the present invention, there is provided a molded article prepared from the above-described polyoxymethylene resin composition.

The molded article has an elongation at break of 150% or more, a Charpy Notched room temperature impact strength (23 ° C) of 53 kJ/m ² or more, and a Charpy Notched low temperature impact strength (-30 ° C) of 12.5 kJ/m ² or more.

The polyoxymethylene resin composition according to the present invention may have excellent room temperature impact resistance and low temperature impact resistance along with excellent mechanical properties.

In addition, the molded article prepared from the polyoxymethylene resin composition according to the present invention has excellent impact resistance at room temperature and low temperature, thereby preventing the molded article from breaking.

The present invention provides a polyoxymethylene resin composition comprising a polyoxymethylene resin, a methyl methacrylate-butadiene-styrene rubber, and a polyurethane styrene composite diene block copolymer.

Hereinafter, the present invention will be described in more detail.

[Polyoxymethylene Resin]

Oxymethylene is the main unit, characterized in that it has units of oxyalkylene having 2 to 8 adjacent carbon atoms among the main units.

The polyoxymethylene resin used in the present invention generally includes a homopolymer, copolymer or terpolymer in which the main unit is an oxymethylene group (-(-OCH ₂ ) _n -). Among these, a copolymer is used in the present invention.

The polyoxymethylene resin can be obtained by cationic random copolymerization of a cyclic oligomer of trioxane or tetraoxane, preferably a cyclic oligomer of trioxane and a comonomer. Comonomers include oxyethylene (-(OCH ₂ CH ₂ ) _n -), oxypropylene (-(OCH ₂ CH ₂ CH ₂ ) _n -), oxybutylene (-(OCH ₂ CH ₂ CH ₂ CH ₂ ) _n A branched oxyalkylene group having 2 to 10 carbon atoms, such as -), may be used. Examples include 1,3-dioxolane, 1,3-dioxephan, and 1,3,5-trioxepane.

In particular, the polyoxymethylene resin used in the present invention can be obtained by adding 1,3-dioxolane comonomer to trioxane, which is the main monomer, followed by cationic random copolymerization using a Lewis acid catalyst. In addition, the structure of the said polyoxymethylene resin may have not only a linear structure but a bridge|crosslinking or branched structure.

[Methyl methacrylate-butadiene-styrene rubber]

In the present invention, the methyl methacrylate-butadiene-styrene rubber may be obtained by graft polymerization of a butadiene-based rubber polymer, a (meth)acrylic acid alkyl ester monomer, and an ethylenically unsaturated aromatic compound.

In this case, the (meth)acrylic acid alkyl ester monomer includes methyl methacrylate, n-butyl methacrylate, benzyl methacrylate, lauryl methacrylate and stearyl methacrylate as an alkyl methacrylate type, Among them, methyl methacrylate may be most preferred. In addition, the ethylenically unsaturated aromatic compound is not limited thereto, but at least one selected from the group consisting of styrene, α-methylstyrene, p-methylstyrene, vinyltoluene and 3,4-dichlorostyrene It may be desirable to use

The methyl methacrylate-butadiene-styrene resin of the present invention has a core-shell structure, and the core part contains butadiene-styrene, and the shell part contains methyl methacrylate to prevent impact. When applied, the rubber part of the core part absorbs the impact force and may exhibit impact resistance properties.

In particular, the glass transition temperature of butadiene-styrene constituting the core part of the methyl methacrylate-butadiene-styrene rubber is very low as -70° C. or less. That is, methyl methacrylate-butadiene-styrene rubber has a glass transition temperature of -70 ° C or less, which means the temperature at which the polymer chain of the amorphous part starts to move, so it is flexible even at a low temperature of -70 ° C. It is possible to exhibit a very advantageous effect for improving low-temperature impact resistance properties.

At this time, in the present invention, when the methyl methacrylate-butadiene-styrene rubber is dispersed on a polyoxymethylene matrix, it is included in 3 to 6 parts by weight based on 100 parts by weight of the polyoxymethylene resin. It may be advantageous to further improve low-temperature impact strength and room-temperature impact strength while maintaining the same content of components.

[Polyurethane Styrene Composite Diene Block Copolymer]

In the present invention, the polyurethane styrene composite diene block copolymer includes (i) a thermoplastic polyurethane and (ii) a thermoplastic elastomer, wherein the thermoplastic elastomer includes an aromatic vinyl compound polymer block and a conjugated diene compound polymer block.

The polyurethane-styrene composite diene block copolymer can be obtained by kneading and reacting (i) a thermoplastic polyurethane and (ii) a thermoplastic elastomer under melt conditions, and extracting and recovering the resultant reaction product by a known method.

The (i) thermoplastic polyurethane included in the polyurethane-styrene composite diene block copolymer is preferably a polyester-based thermoplastic polyurethane, and a polyester-based thermoplastic polyurethane using an aliphatic polyester as a soft segment. This is more preferable.

(ii) the aromatic vinyl compound polymer block included in the thermoplastic elastomer includes a hydroxyl group at the terminal, and the aromatic vinyl compound constituting the aromatic vinyl compound polymer block is styrene, α-methylstyrene, 2-methylstyrene Rene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4-benzylstyrene, 4-(phenylbutyl) Styrene etc. are mentioned, Styrene and 4-methylstyrene are preferable.

The conjugated dienes constituting the conjugated diene compound polymer block included in the (ii) thermoplastic elastomer are butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, and 1,3-pentadiene. ene, 1,3-hexadiene, and the like, and it is preferable to have a structural unit derived from butadiene or isoprene. In addition, the bonding form of the conjugated diene is not particularly limited, but it is preferable that the 1,4-bond amount of butadiene or isoprene is 90 to 98%.

The polyurethane-styrene composite diene block copolymer is characterized in that the mass ratio of (i) thermoplastic polyurethane and (ii) thermoplastic elastomer is 80:20-20:80, and preferably 40:60-60:40. do.

The weight average molecular weight of the polyurethane styrene composite diene block copolymer is 30,000 to 300,000 g/mol, preferably 50,000 to 200,000 g/mol, and most preferably 70,000 to 130,000 g/mol. The weight average molecular weight was measured using Gel Permeation Chromatography (GPC), and polystyrene was used as a standard material and tetrahydrofuran (THF) was used as a solvent.

The polyurethane styrene composite diene block copolymer may have a shore A hardness of 75 to 85, and may include (i) a thermoplastic polyurethane having a shore A hardness of 70 to 75. When the shore A hardness of the polyurethane styrene composite diene block copolymer is within the above range, the glass transition temperature of the polyurethane styrene composite diene block copolymer may be -40 to -30°C. The thermoplastic polyurethane composite hydrogenated diene block copolymer has flexible properties even at low temperatures, and is dispersed in a polyoxymethylene matrix when prescribed to obtain the effect of improving room temperature impact resistance and low temperature impact resistance.

The polyurethane styrene composite diene block copolymer is included in an amount of 0.5 to 8 parts by weight based on 100 parts by weight of the polyoxymethylene resin, so that mechanical properties such as impact resistance, tensile strength, elongation at break, and flexural strength of the polyoxymethylene resin are can be improved, and in particular, it may be more advantageous to obtain excellent room temperature impact resistance properties.

In addition, the polyurethane styrene composite diene block copolymer may be a polyurethane styrene composite diene block copolymer in which a part or all of the conjugated diene compound polymer block has undergone a hydrogenation reaction. Since the polyurethane styrene composite diene block copolymer is saturated with double bonds of the conjugated diene by hydrogenation reaction, heat resistance is improved to prevent decomposition during high-temperature processing, thereby preventing deterioration of mechanical properties.

The polyoxymethylene resin composition of the present invention may further include a thermoplastic polyurethane, an ethylene acrylate copolymer, or a polyether-ester block copolymer.

[Thermoplastic polyurethane]

The thermoplastic polyurethane used in the present invention is produced by reacting a polyol constituting a soft segment with a diisocyanate constituting a hard segment and a low molecular weight diol acting as a chain extender. The material, in which a soft segment and a hard segment exist together, is dispersed in a polyoxymethylene matrix and acts as an impact resistant agent that absorbs and mitigates impact when an impact is applied from the outside.

Polyols constituting the soft segment include polyester-diol such as polyethylene-adipate and polybutylene-adipate, and polyether-diol such as polypropylene-glycol and polytetramethylene-glycol. All can be used. As the diisocyanate constituting the hard segment, 4,4'-diphenyl methane diisocyanate, 4,4'-dicyclohexyl methane diisocyanate, or the like may be used. As the low molecular weight diol as a chain extender, ethylene-glycol, tetramethylene-glycol, etc. may be used. In addition, the thermoplastic polyurethane of the present invention is produced using a conventional method.

As the blending amount of the thermoplastic polyurethane, 20 to 30 parts by weight based on 100 parts by weight of the polyoxymethylene resin is more advantageous in that it is evenly dispersed in the polyoxymethylene matrix and serves to absorb the impact force when an impact is applied. do.

[Ethylene acrylate copolymer]

The present invention includes ethylene acrylate copolymers. In particular, the ethylene acrylate copolymer is a compound represented by the following formula (1), and preferably has an alkyl group having 1 to 3 carbon atoms bonded to the acrylate.

<Formula 1>

(Wherein, R ₁ is an alkyl group having 1 to 3 carbon atoms, x is an integer of 60 to 130, and y is an integer of 10 to 20.)

When the number of carbon atoms in R ₁ of the acrylate group in Formula 1 is 1 to 3, methyl methacrylate-butadiene-styrene rubber in a polyoxymethylene matrix, polyurethane styrene composite diene block copolymer, It is uniformly dispersed with the thermoplastic polyurethane and polyether-ester block copolymer and has the effect of increasing impact resistance. In addition, in the case of not having R ₁ in Formula 1, there is no portion capable of absorbing an impact even when dispersed in a polyoxymethylene matrix, so there is a problem in that the impact resistance property is rapidly reduced.

In addition, the ethylene acrylate copolymer may be used in a mass ratio of 85:15 to 70:30 of the ethylene polymer and the acrylate polymer.

When the mass ratio of the ethylene polymer and the acrylate polymer is within the above range, the glass transition temperature is flexible to -15° C. or less, so that the effect of modifying the room temperature impact resistance and low temperature impact resistance properties can be obtained during prescription.

It is preferable that the ethylene acrylate copolymer be 4 parts by weight or more based on 100 parts by weight of the polyoxymethylene resin so that the effect as an impact agent can be sufficiently realized. In order to prevent it, it is better to contain 7 parts by weight or less based on 100 parts by weight of the polyoxymethylene resin.

[Polyether-ester block copolymer]

In the present invention, a polyether-ester block copolymer is added, and the copolymer is a random block copolymer prepared by polymerization of dimethyl terephthalate, 1,4-butanediol, and polytetramethylene oxide glycol. The polyether-ester block copolymer has both a soft segment and a hard segment. Among them, the soft segment is produced by the reaction of dimethyl terephthalate and polytetramethylene oxide, and the hard segment is produced by the reaction of dimethyl terephthalate and 1,4-butanediol. In the polyether-ester block copolymer, the soft segment is much longer than that of the hard segment, giving flexibility and recovery properties.

In particular, in the present invention, a polyether-ester block copolymer having a mass ratio of a soft segment and a hard segment of 68:32 to 40:60 and a shore D hardness of 28 to 55 may be used.

When the mass ratio of the soft segment and the hard segment is within the above range, the glass transition temperature is very low below -30 ° C. can be obtained, and when the shore D hardness is within the above range, the elongation at break is very high, so that it is dispersed in a polyoxymethylene matrix to obtain an advantageous effect in enhancing the elongation at break of the composition.

In addition, the polyether-ester block copolymer is preferably 4 parts by weight or more based on 100 parts by weight of the polyoxymethylene resin so that the effect as an auxiliary impact resistance agent can be sufficiently realized, and the elongation at break decreases and the die swell during extrusion processing. In order to prevent this formation, it is better to contain 7 parts by weight or less based on 100 parts by weight of the polyoxymethylene resin.

On the other hand, in the range that does not offset the effects of the present invention, the polyoxymethylene resin composition may additionally include additives such as a hindered phenolic antioxidant, a mold release agent, a colorant, a plasticizer, a nucleating agent, and a formaldehyde scavenger.

In the present invention, the hindered phenolic antioxidant serves to prevent the continuous destruction of the polymer bond by catching radicals generated when the bond is broken when heat is applied to the resin. Materials that can be used as the hindered phenol antioxidant include n-octadecyl-3-(3,5'-di-tertiary-butyl-4-hydroxyphenyl)-propionate, triethylene glycol-bis -[3-(3-tert-Butyl-5-methyl-4-hydroxyphenyl)-propionate], 2,2'-methylene bis-(4-methyl-tert-butylphenol), tetrakis [methylene-3-(3,5'-di-tertiary-butyl-4-hydroxyphenyl)propionate]methane, N,N'-bis-3-3(3,5'-di-tertiary -Butyl-4-hydroxyphenyl)propionylhexamethylenediamine, N,N'-tetramethylene-bis-3-(3-methyl-5-tertiary-butyl-4-hydroxyphenol)propionyldia Min, N,N'-bis-[3-(3,5'-di-tert-butyl-4-hydroxyphenol)propionyl]hydrazine, N-sarithiroyl-N-sarithiridenehydrazine, 3-(N-satiroyl)amino-1,2,4-triazole and N,N'-bis[2-{3-(3,5'-di-tertiary-butyl-4-hydroxy phenyl) propionyloxy}ethyl]oxyamide. In particular, antioxidants that can be preferably used in the present invention are tetrakiz[methylene-3-(3,5'-di-tertiary-butyl-4-hydroxyphenyl)propionate]methane and triethylene glycol- bis-3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate. An effect can be obtained by selectively using one type or a combination of two or more types of these antioxidants.

The hindered phenol antioxidant is preferably included in an amount of 0.01 to 0.1 parts by weight based on 100 parts by weight of the polyoxymethylene resin in order not to act as an impurity while considering the sufficient effect of oxidation prevention.

In the present invention, the release agent is added for the purpose of securing injection property and for the purpose of helping processability. As the releasing agent, at least one selected from substances including paraffin wax, oxidized paraffin wax, polyethylene wax, low molecular weight ethylene vinyl acetate, N,N'-ethylene bis stearamide, erucamide, and oleamide can be used. have. In particular, the mold release agent that can be preferably used in the present invention is N,N'-ethylene bead stearamide.

The release agent is preferably included in an amount of 0.01 to 0.1 parts by weight based on 100 parts by weight of the polyoxymethylene resin in order not to act as an impurity while considering a sufficient effect to help processability.

Accordingly, the present invention can provide a polyoxymethylene resin composition capable of preventing cracking during product manufacturing by having very excellent room temperature impact resistance and low temperature impact resistance properties of a molded article.

According to another embodiment of the present invention, there is provided a molded article prepared from the above-described polyoxymethylene resin composition.

The molded article manufactured using the polyoxymethylene composition of the present invention has an elongation at break of 150% or more, a Charpy Notched room temperature impact strength (23℃) of 53kJ/m ² or more, and a Charpy Notched low temperature impact strength (-30℃) of 12.5kJ/ m ² or more, it has excellent mechanical properties as well as impact resistance at room temperature and low temperature. More excellently, it is possible to realize physical properties of over 170% elongation at break, Charpy Notched room temperature impact strength (23℃) of 60kJ/m ² or more, and Charpy Notched low temperature impact strength (-30℃) of 13kJ/m ² or more.

In addition, the molded article manufactured using the polyoxymethylene composition of the present invention may have a tensile strength and a flexural strength of 38 MPa or more, and a flexural modulus of 1,350 MPa or less.

[Example]

Hereinafter, the present invention will be described in more detail through examples. These examples are only for illustrating the present invention, and it will be apparent to those of ordinary skill in the art that the scope of the present invention is not to be construed as being limited by these examples.

Examples 1 to 11

Thermoplastic polyurethane, ethylene acrylate copolymer, polyether-ester block copolymer, methyl methacrylate-butadiene-styrene rubber, and polyurethane styrene composite diene block copolymer were added in polyoxymethylene resin. A polyoxymethylene resin composition was prepared by using the amounts of the hindered phenol-based antioxidant and the release agent as shown in Table 1.

Comparative Examples 1 and 2

As shown in Table 1, a polyoxymethylene resin composition was prepared in the same manner as in Example 1, except that the methyl methacrylate-butadiene-styrene rubber or polyurethane styrene composite diene block copolymer was changed. did.

Comparative Examples 3 and 4

Thermoplastic polyurethane, ethylene acrylate copolymer, polyether-ester block copolymer, methyl methacrylate-butadiene-styrene rubber, polyurethane styrene composite diene block copolymer, hindered phenol in polyoxymethylene resin A polyoxymethylene resin composition was prepared with the addition amount of the antioxidant and the release agent in the ratio shown in Table 1.

Physical property evaluation

The physical properties of the polyoxymethylene resin compositions prepared in Examples and Comparative Examples were measured by the following method, and the results are shown in Table 2.

1. Tensile strength and elongation at break

: Measured at a test speed of 50 mm/min based on ISO 527 standards.

2. Flexural strength and flexural modulus

: Based on ISO 178 standards, it was measured with a span length of 64 mm and a test speed of 2 mm/min.

3. Room temperature impact strength, low temperature impact strength

: Based on ISO 179/1eA standard, Charpy Notched impact strength was measured at room temperature 23℃ and low temperature -30℃.

division go me all la mind bar buy ah ruler car card get on Example 1 100 27 6 0 0 6 3 0 2 0 0.1 0.1 Example 2 100 27 0 6 0 6 3 0 2 0 0.1 0.1 Example 3 100 27 0 0 6 6 3 0 2 0 0.1 0.1 Example 4 100 27 7 0 0 4 3 0 2 0 0.1 0.1 Example 5 100 27 4 0 0 7 3 0 2 0 0.1 0.1 Example 6 100 29 6 0 0 6 3 0 0.5 0 0.1 0.1 Example 7 100 29 6 0 0 6 0.5 0 2 0 0.1 0.1 Example 8 100 24 6 0 0 6 6 0 2 0 0.1 0.1 Example 9 100 24 6 0 0 6 7 0 2 0 0.1 0.1 Example 10 100 20 6 0 0 6 3 0 8 0 0.1 0.1 Example 11 100 20 6 0 0 6 3 0 10 0 0.1 0.1 Comparative Example 1 100 27 6 0 0 6 0 3 2 0 0.1 0.1 Comparative Example 2 100 27 6 0 0 6 3 0 0 2 0.1 0.1 Comparative Example 3 100 29 6 0 0 6 0 0 2 0 0.1 0.1 Comparative Example 4 100 29 6 0 0 6 3 0 0 0 0.1 0.1

A: Polyoxymethylene resin (Kolon Plastic K100HS NC)

B: Thermoplastic polyurethane (Songwon, P-3175A)

C: Ethylene-butyl acrylate copolymer (Dupont, AC3427)

D: Ethylene-ethyl acrylate copolymer (UBE, ZE708)

E: ethylene-methyl acrylate copolymer (Arkema, 29MA03T)

Bar: polyether-ester block copolymer (Kolon Plastics, KP3328)

Yarn: methyl methacrylate-butadiene-styrene rubber (Dow, EXL2600J)

H: Acrylic Impact Modifier (AIM) (Kuraray, LA2330)

Ruler: Polyurethane Styrene Composite Diene Block Copolymer (Kuraray, TU-S5265)

Tea: Styrene Ethylene Butylene Styrene Block Copolymer (Styrene Ethylene Butylene Styrene, SEBS) (LCY, Globalprene 9550)

Car: hindered phenolic antioxidant (Songwon, SONGNOX 1010)

Other: Lee Hyung-jae (Shinwon Chemical, HI-LUBE 500P)

The tensile strength
(MPa) break elongation
(%) flexural strength
(MPa) flexural modulus
(MPa) Charpy notched
impact strength
(23℃, kJ/m ² ) Charpy notched
impact strength
(-30℃, kJ/m ² ) Example 1 39.2 176 41.2 1,268 66 15.5 Example 2 39.8 172 41.3 1,257 61 14.2 Example 3 39.1 188 41.5 1,271 61.5 14 Example 4 39.2 193 42 1,302 66.6 13.2 Example 5 39.4 184 41.7 1,306 60.9 13.5 Example 6 39.6 192 42.3 1,332 67.7 15 Example 7 39.9 163 42.7 1,335 59.4 12.8 Example 8 39.5 175 42.7 1,341 60.8 14.1 Example 9 38.7 160 40.8 1,251 56.2 13.3 Example 10 38.6 185 41.4 1,303 68.1 15.3 Example 11 38.0 151 40.8 1,270 53.3 13.5 Comparative Example 1 39.9 120 43 1,331 42.9 10.7 Comparative Example 2 39.4 166 45.3 1,310 37.7 14.2 Comparative Example 3 39.7 146 41.7 1,292 56.1 10.5 Comparative Example 4 39.9 175 42.8 1,333 45.4 12.3

As confirmed in Examples 1 to 11, polyoxymethylene resin, thermoplastic polyurethane, ethylene acrylate copolymer, polyether-ester block copolymer, methyl methacrylate-butadiene-styrene rubber, polyurethane styrene It can be seen that when the Lene composite diene block copolymer is added, it has excellent tensile strength, elongation at break, and flexural strength, and particularly has excellent room temperature impact resistance and low temperature impact resistance.

Comparative Example 1 includes 2 parts by weight of a polyurethane styrene composite diene block copolymer, but instead of methyl methacrylate-butadiene-styrene rubber, a commonly used acrylic impact modifier (AIM) 2 By including parts by weight, it can be seen that tensile strength, flexural strength, and flexural modulus are slightly improved compared to Example 1, but elongation at break, room temperature impact resistance and low temperature impact resistance properties are significantly reduced.

Comparative Example 2 includes 3 parts by weight of methyl methacrylate-butadiene-styrene rubber, but a styrene ethylene butylene styrene block copolymer (Styrene) commonly used instead of a polyurethane styrene composite diene block copolymer Ethylene Butylene Styrene, SEBS) is included in 2 parts by weight, and compared with Example 1, tensile strength, flexural strength, and flexural modulus are slightly improved, but elongation at break and low-temperature impact resistance properties are slightly lowered, and in particular, impact resistance properties at room temperature are significantly improved. degradation can be seen.

Comparative Example 3 does not include methyl methacrylate-butadiene-styrene rubber, but 2 parts by weight of polyurethane styrene composite diene block copolymer is included, and the same amount of polyoxymethylene resin is used. Compared with Example 7, it can be seen that the tensile strength, flexural strength, flexural modulus, and room temperature impact resistance properties are slightly lowered, while the elongation at break and low temperature impact resistance properties are significantly lowered.

Comparative Example 4 is a case in which the polyurethane styrene composite diene block copolymer is not included, but 3 parts by weight of methyl methacrylate-butadiene-styrene rubber is included, and the same amount of polyoxymethylene resin is used. Compared to Example 6, the tensile strength, flexural strength, and flexural modulus were slightly improved, but it was confirmed that the elongation at break and the low-temperature impact resistance properties were slightly decreased, and in particular, the room temperature impact resistance properties were significantly reduced.

As described above in detail a specific part of the content of the present invention, for those of ordinary skill in the art, it is clear that this specific description is only a preferred embodiment, and the scope of the present invention is not limited thereby. will be. Accordingly, it is intended that the substantial scope of the present invention be defined by the appended claims and their equivalents.

Claims (15)

polyoxymethylene resin; methyl methacrylate-butadiene-styrene rubber; polyurethane styrene composite diene block copolymers; thermoplastic polyurethane; ethylene-butyl acrylate copolymer; and a polyether-ester block copolymer, wherein the polyoxymethylene resin composition does not contain an isocyanate compound. According to claim 1, wherein the polyoxymethylene resin composition is methyl methacrylate-butadiene-styrene rubber 3 to 6 parts by weight based on 100 parts by weight of the polyoxymethylene resin and polyurethane styrene composite diene block air A polyoxymethylene resin composition comprising 0.5 to 8 parts by weight of the coal. The method according to claim 1, wherein the polyurethane styrene composite diene block copolymer comprises (i) a thermoplastic polyurethane and (ii) a thermoplastic elastomer, wherein the thermoplastic elastomer comprises an aromatic vinyl compound polymer block and a conjugated diene compound polymer block. Polyoxymethylene resin composition comprising a. The polyoxymethylene resin composition according to claim 3, wherein the polyurethane-styrene composite diene block copolymer has a mass ratio of (i) thermoplastic polyurethane and (ii) thermoplastic elastomer of 80:20 to 20:80. . The polyoxymethylene resin composition according to claim 1, wherein the polyurethane styrene composite diene block copolymer has a weight average molecular weight of 30,000 to 300,000 g/mol. The polyoxymethylene resin according to claim 1, wherein the polyurethane-styrene composite diene block copolymer has a shore A hardness of 75 to 85, and (i) the thermoplastic polyurethane has a shore A hardness of 70 to 75. composition. The polyoxymethylene resin composition according to claim 1, wherein the polyurethane styrene composite diene block copolymer has a glass transition temperature of -40 to -30°C. According to claim 1, wherein the methyl methacrylate-butadiene-styrene rubber has a core-shell structure comprising a core formed of butadiene-styrene rubber and a shell formed of methyl methacrylate. A polyoxymethylene resin composition. According to claim 1, wherein the polyoxymethylene resin composition is 20 to 30 parts by weight of thermoplastic polyurethane, 4 to 7 parts by weight of ethylene-butyl acrylate copolymer, and polyether-ester block based on 100 parts by weight of the polyoxymethylene resin. A polyoxymethylene resin composition comprising 4 to 7 parts by weight of the copolymer. delete The polyoxymethylene resin composition according to claim 9, wherein the ethylene-butyl acrylate copolymer has a mass ratio of 85:15 to 70:30 between the ethylene polymer and the acrylate polymer in the ethylene acrylate copolymer. 10. The method of claim 9, wherein the polyether-ester block copolymer is characterized in that the mass ratio of the soft segment to the hard segment in the polyether-ester block copolymer is 68:32-40:60. A polyoxymethylene resin composition. The polyoxymethylene resin composition according to claim 9, wherein the polyether-ester block copolymer has a shore D hardness of 28 to 55. A molded article prepared from the polyoxymethylene resin composition of any one of claims 1 to 9 and 11 to 13. 15. The method according to claim 14, wherein the molded article has an elongation at break of 150% or more, a Charpy Notched room temperature impact strength (23°C) of 53 kJ/m ² or more, and a Charpy Notched low temperature impact strength (-30° C.) of 12.5 kJ/m ² or more. Characterized molded article.