KR20170068102A

KR20170068102A - Polypropylene resin composition for a corrugate tube and Products obtained by employing the same

Info

Publication number: KR20170068102A
Application number: KR1020150174919A
Authority: KR
Inventors: 김정원; 한정환; 이형원
Original assignee: 한화토탈 주식회사
Priority date: 2015-12-09
Filing date: 2015-12-09
Publication date: 2017-06-19
Also published as: JP6316343B2; JP2017105972A

Abstract

The present invention relates to a polypropylene resin composition for a corrugated tube for an automobile, and more particularly, to a polypropylene resin composition for a corrugated tube for automobiles, which can improve the long-term thermal stability of a polypropylene-based corot tube and can be used in an engine room To a polypropylene resin composition for a corrugated tube for automobiles.

Description

TECHNICAL FIELD [0001] The present invention relates to a polypropylene resin composition for a corrugated tube and a molded article produced using the same.

Corrugated tubes for automobiles can be divided into polypropylene type and nylon type on the material side. Nylon corrugated tubes are used for engine room and car floor, and polypropylene corrugated tubes are used for applications where long term heat resistance is not required.

Conventional polypropylene type corrugated tubes have been mainly made of non-burned or flame-retardant polypropylene. Non-burned polypropylene is used for indoor use with little thermal effect. However, since flame retardant polypropylene is thermally affected, flame retardancy of UL V-2 level is required. A related art related to the above relates to a flame retardant polypropylene resin composition in Korean Patent No. 10-0796730. However, the flame retardant polypropylene resin composition has no purpose of improving long-term thermal stability.

In recent years, an attempt has been made to apply a flame retardant polypropylene type corot tube to a nylon corot tube. At this time, the important technical task is to have long term heat resistance close to nylon level.

The present invention improves long-term thermal stability for flame-retardant polypropylene-based corot tube and makes it possible to use it in the engine room or on the floor of an automobile.

It is an object of the present invention to provide a polypropylene resin composition for a corrugated tube which can be used in an engine room or on the floor of an automobile by improving the long-term thermal stability of a conventional polypropylene type corrugated tube for automobiles.

In order to accomplish the object of the present invention, the present invention provides a polypropylene resin composition comprising: 1 to 30 parts by weight of a flame retardant; 0.1 to 7 parts by weight of a flame retardant auxiliary; And 0.15 to 15 parts by weight of an antioxidant, wherein the antioxidant is a mixture of at least three antioxidants selected from a phenol-based antioxidant, an aromatic amine-based antioxidant, a phosphorus-based antioxidant and a sulfur- The present invention provides a polypropylene resin composition comprising

The polypropylene resin composition according to the present invention is advantageous in that it can be used for engine room and automobile flooring because of its high long-term thermal stability despite being a polypropylene resin composition.

Nylon type corrugated tubes have been used as corotate tubes for existing automobile engine rooms or automotive flooring. However, if nylon type corrugated tubes are replaced with polypropylene type corrugated tubes that have excellent long-term heat resistance, Energy costs can also be reduced when machining corrugated tubes.

Hereinafter, the present invention will be described in more detail. Hereinafter, preferred embodiments of the present invention and physical properties of the respective components will be described in detail with reference to the accompanying drawings. However, the present invention is not limited thereto, And this does not mean that the technical idea and scope of the present invention are limited.

According to one embodiment of the present invention, the flame retardant is added to 1 to 30 parts by weight of the flame retardant relative to 100 parts by weight of the polypropylene resin; 0.1 to 7 parts by weight of a flame retardant auxiliary; And 0.15 to 15 parts by weight of an antioxidant, wherein the antioxidant is a mixture of at least three antioxidants selected from a phenol-based antioxidant, an aromatic amine-based antioxidant, a phosphorus-based antioxidant and a sulfur- The present invention provides a polypropylene resin composition comprising

<Polypropylene resin>

According to one embodiment of the present invention, the polypropylene resin is preferably a block copolypropylene, and may further comprise homopolypropylene or random polypropylene. The aforementioned block copolypropylene may further contain propylene as a main component and a monomer such as ethylene, 1-butene, 1-hexene, 1-octene, 4-methyl-1-pentene as an auxiliary component. Specifically, the above-mentioned block copolypropylene contains 1 to 13 wt% of ethylene (B-C2) bonded to the chain with propylene as a main component, and the 1-butene, 1-hexene, And an alpha-olefin such as 1-pentene. The melt index of the block copolypropylene is preferably 0.1 to 3 g / 10 min (ASTM D1238, 2.16 kg, 230).

If the above-mentioned melt index is less than 0.1 g / 10 min, the extrusion performance of the corrugated tube is deteriorated. If the melt index exceeds 3 g / 10 min, the elongation suitable for the corotated tube is not obtained.

The polypropylene suitable for the corrugated tube for automobiles of the present invention is a polypropylene resin having a elongation of 300% or more.

The polypropylene resin composition suitable for the corrugated tube of the present invention preferably has a elongation retention of 30% or more when left in an oven at 150 ° C for 70 days. If the elongation retention is less than 30%, the long-term heat resistance is insufficient.

< Flame retardant >

According to one embodiment of the present invention, when the flame retardant comes to have flame retardancy of UL94 V-2 grade, the kind of the flame retardant is not specifically proposed.

According to one embodiment of the present invention, a halogen flame retardant, a functional inorganic compound flame retardant, and a phosphorus flame retardant may be preferably used.

Examples of the halogen-based flame retardant include tetrabromobisphenol A, hexabromocyclododecane, decabromodiphenyl ether, dodecachlorodotahydro methanodibenzocyclo octene, bis (pentabromophenyl) ethane, tetrabromobisphenol A Based flame retardants, and tetrabromobisphenol S-based flame retardants.

Examples of the functional inorganic flame retardant include magnesium hydroxide, aluminum hydroxide, and hydrotalcite.

Phosphorous flame retardants include triallyl phosphate, alkyl diaryl phosphate, trialkyl phosphate, resorcinol bisdiphenyl phosphate, and the like.

The content of the above-mentioned flame retardant in the present invention is preferably 1 to 30 parts by weight of the flame retardant relative to 100 parts by weight of the polypropylene resin. If the content of the flame retardant exceeds 30 parts by weight, the moldability is poor. If the content of the flame retardant is less than 1 part by weight, sufficient flame retardancy is not obtained.

<Flame Retardant Preparation>

According to an embodiment of the present invention, the flame retardant aid may be selected from at least one of antimony trioxide, antimony pentoxide, and boron compounds.

The content of the flame retarder may be in the range of 0.1 to 7 parts by weight based on 100 parts by weight of the polypropylene resin. Flame retardant additives have a flame retarding synergistic effect when used together with flame retardants. However, even when the content of the flame retarder is used in excess of 7 parts by weight, the flame retardancy does not increase any further. When the content of the flame retarder is less than 0.1 part by weight, it is difficult to obtain sufficient flame retardancy.

<Antioxidant>

According to one embodiment of the present invention, it is preferable that at least three or more kinds of the antioxidants are used in combination with one another, and in particular, phenol antioxidants, aromatic amine antioxidants, phosphorus antioxidants, It is preferably used as a mixture of at least three kinds of antioxidants selected from among antioxidants.

The polymer chains undergo oxidative deterioration through an automatic oxidation process. That is, radicals are formed on the polymer chain by heat, light, mechanical stress, residual catalyst / impurities and reaction. Among the three types of antioxidants, the primary antioxidant serves to capture the radicals thus produced. Radicals not captured by the primary antioxidant react with oxygen to form peroxide radicals. The peroxide radical reacts with the hydrocarbons to form peroxides.

The peroxide thus formed is converted into alcohol and keyton by the secondary antioxidant among three or more antioxidants, and the decomposition process of the polymer chain is stopped. Secondary antioxidants are more effective when used in combination with primary antioxidants than those used alone.

The third antioxidant among the three or more antioxidants is preferably an antioxidant capable of exhibiting long-term heat resistance. Such a long-term heat-resistant antioxidant may be obtained by converting the peroxide into alcohol and keyton, It plays a role. However, the secondary antioxidant plays a role of preventing oxidation at a temperature of 170 ° C or higher, while the long-term heat resistant antioxidant has a role of preventing oxidation of the polymer chain at a temperature of 150 ° C or lower.

The total content of the three or more kinds of antioxidants is preferably 0.15 to 15 parts by weight based on 100 parts by weight of the polypropylene resin

When the total amount of the antioxidant is less than 0.15 parts by weight, the long term heat resistance is deteriorated. If the total amount exceeds 15 parts by weight, yellowing may occur.

Wherein the mixture of the antioxidants is one wherein the phenolic antioxidant or the aromatic amine antioxidant is the primary antioxidant, the phosphorus antioxidant is the secondary antioxidant, the sulfur antioxidant is the tertiary antioxidant, The second antioxidant is 0.05 to 5 parts by weight, and the third antioxidant is 0.1 to 5 parts by weight.

The content of the primary antioxidant is more preferably 0.1 to 3 parts by weight.

If the content of the primary antioxidant is less than 0.1 part by weight, the aimed long-term heat resistance of the present invention can not be secured. When the content of the first antioxidant exceeds 5 parts by weight, yellowing easily occurs under the same conditions as NOx.

As the phenolic antioxidant, a hindered phenol system was applied. For example, 2,6-di-tert-butyl-4-methylphenol (BHT), thiodiethylene bis [2- (3,5- Di-tert-butyl-4-hydroxyphenyl) propionate, Songnox 1035), octadecyl-3- (3 Octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, Songox1076), tetrakis [methylene- - (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane (tetrakis [methylene- Songox 1010) or the like.

Examples of the aromatic amine antioxidant include phenylnaphthylamine, 4,4 '- (?,? - dimethylbenzyl) diphenylamine, and N, N'-di-2-naphthyl- , 4'-dioctyldiphenylamine, N, N'-diphenyl-P-phenylenediamine, N-phenyl-N'-cyclohexyl-P- -Ethylenediamine, and alkylated diphenylamine can be used.

In the present invention, a phosphorus-based antioxidant may be used as the secondary antioxidant, and examples thereof include tris (2,4-di-tert-butylphenyl) phosphite, (2,4-di-tert-butylphenyl) pentaerythritol diphosphite (Tris (nonylphenyl) phosphite, TNPP) -butylphenyl) pentaerythritol diphosphite) and the like.

The content of the secondary antioxidant is preferably 0.05 to 5 parts by weight. If the content of the second antioxidant is less than 0.05 part by weight, the effect of preventing degradation of the polymer is deteriorated. If the content of the second antioxidant is more than 5 parts by weight, excessive secondary antioxidant may form phosphorous acid, have.

As the tertiary antioxidant of the present invention, that is, long-term heat-resistant antioxidant, at least one of sulfur-based compounds such as di-stearyl thiodipropionate, ditridecyl thiodipropionate, and diaryl thiodipropionate You can choose to use it.

The content of the long-term heat-resistant antioxidant is preferably 0.1 to 5 parts by weight. If the content of the long-term heat-resistant antioxidant is less than 0.1 parts by weight, the effect of preventing the deterioration of polymer deteriorates. If the content of the long-term heat-resistant antioxidant is more than 5 parts by weight, .

The polypropylene resin composition according to the present invention may contain, in addition to the above-mentioned components, additives such as processing lubricants, ultraviolet stabilizers, long-term heat stabilizers, antistatic agents, metal deactivators, polyethylene waxes, , And the like.

The lubricant may be a metal soap lubricant or an amide lubricant.

The metal soap based lubricant refers to a substance synthesized by an ester reaction between an organic fatty acid and a metal oxide, and examples thereof include zinc stearate, calcium stearate, magnesium stearate, and aluminum stearate. These lubricants may be used alone or as a mixture. Particularly, calcium stearate is preferably used. The metal soap-based lubricant may be used in an amount of 0 to 5 parts by weight, preferably 0 to 3 parts by weight, based on 100 parts by weight of the total polypropylene resin.

Examples of such amide-based lubricants include ethylene-bis-stearyl amide, ethylene-bis-oleamide, glycerin mono-stearate, sorbitan monopalmitate, erucamide, . In particular, it is preferred to use ethylene-bis-stearyl-amide. The amide-based lubricant may be used in an amount of 0 to 5 parts by weight, preferably 0 to 3 parts by weight, based on 100 parts by weight of the total polypropylene resin.

The polyethylene wax is preferably an oligomer type polyethylene having a weight average molecular weight of 100 to 10,000 g / mol by decomposing the high molecular weight polyethylene. The polyethylene wax may be used in an amount of 0 to 10 parts by weight, preferably 0 to 5 parts by weight, based on 100 parts by weight of the total polypropylene resin.

The metal soap-based lubricant, the amide-based lubricant, and the polyethylene wax can improve the processability and moldability of the polypropylene resin composition.

The present invention will be more specifically illustrated by the following examples, but the following examples are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

< Example 1 to 7 and Comparative Example 1 to 4>

The contents of the block copolypropylene and each additive were weighed as shown in Table 1, mixed with a Henschel mixer, put into a main hopper of a biaxial extruder (SM PLATEK, screw diameter 30Φ), and the barrel temperature of the extruder was changed to 150 - Kneaded at 220 DEG C under an extrusion rate of 10 to 20 kg / hr and a screw rotation speed of 350 rpm to prepare a polypropylene resin composition.

(Unit: parts by weight) Comparative Example Example One 2 3 4 One 2 3 4 5 6 PP-1 100 100 100 100 100 100 100 100 100 100 Flame Retardant 1 2 2 2 2 2 2 2 2 4 4 Flame Retardant 2 One One One One One One One One 3 3 Flame retardant preparation One One One One One One One One 2 2 Primary antioxidant 0.01 0.15 0.15 0 0.16 0.5 1.6 4 4 5 Secondary antioxidant 0.04 0.07 0 0.5 0.07 0.5 0.9 2 2 3 Long-term heat-resistant antioxidant 0.09 0 0.2 0.2 0.2 0.5 0.9 3 3 4 Melt Index 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.3 1.0 1.0 Flammability
(UL 94 V-2) V-2 V-2 V-2 V-2 V-2 V-2 V-2 V-2 V-2 V-2 My blooming ability O O O O O O O O O O Elongation retention rate (%) One 10 23 8 35 46 57 68 63 72

Flame retardant 1: DBP-TBS Bis (3,5-dibromo-4- (2,3-dibromopropoxy) phenyl) sulfone, Suzuhiro

Flame retardant 2: DBP-TBA Tetrabromobisphenol A bis (2,3-dibromopropyl ether), Dead Sea

Flame Retardant: Antimony Trioxide, Sinochem plastics company

PP-1: block copolypropylene with MI = 1, elongation 500%

Long-term heat-resistant antioxidant: distearyl thiodipropionate

Experimental Example :

Using the resin compositions prepared according to the above Examples and Comparative Examples, the physical properties were measured as follows.

(1) Flammability (UL 94 V -2): The flammability test of plastic materials for mechanical parts of UL subject 94 (Underwrites Laboratories Incorporation) was based on the "Vertical Combustion Test (V-2) mm.

(2) Blooming property in a polypropylene composition : The polypropylene composition was injection molded to produce a specimen thickness of 2.0 mm x 129 mm x 118 mm. Injection molding machine was injection molding machine using Toyo 180 tons injection molding machine. Injection molding temperature was 30/210/220/220/220 ℃, nozzle temperature 60 ℃, injection pressure 60 ~ Specimens were prepared. The 2T specimen was left in a 70 ° C oven for 72 hours to evaluate the appearance of the specimen.

O: Good specimen appearance

X: white powder on surface of specimen

(3) Elongation retention ( % ): The polypropylene composition was injected into a mold of ASTM No. 1 using a Toyo 180-ton extruder and stored for 2 days at a temperature of 23 ± 2 ° C. and a relative humidity of 50 ± 5% Tensile strength is measured at a rate of 50 mm per minute (E1).

The specimen is further heat treated in an oven at 150 ° C. for 70 days, and the elongation is measured under the above conditions (E2). The elongation retention rate is obtained by the following equation (1).

Items not described in this test method are tested according to ASTM D638.

Elongation Retention Rate (%) = E2 / E1 X 100 (1)

(4) Melt Index (MI): Measured at 230 DEG C (polypropylene) and 190 DEG C (polyethylene) at a load of 2.16 kg according to ASTM D1238.

According to Table 1, when the three or more kinds of antioxidants are used according to the present invention, it is found that the elongation retention rate is 30% or more and the long-term heat resistance is excellent. However, even if it does not contain any one or three or more kinds of antioxidants, if it is not included in the weight ratio of the antioxidant according to the present invention, it can be seen that the long-term heat resistance is low due to a low elongation retention rate.

Claims

With respect to 100 parts by weight of the polypropylene resin
1 to 30 parts by weight of a flame retardant;
0.1 to 5 parts by weight of a flame retardant auxiliary; And
0.15 to 15 parts by weight of an antioxidant,
Wherein the antioxidant is a mixture of at least three kinds of antioxidants selected from phenol antioxidants, aromatic amine antioxidants, phosphorus antioxidants and sulfur antioxidants.

The method according to claim 1,
Wherein the mixture of the antioxidants is a phenol-based antioxidant or an aromatic amine-based antioxidant as the primary antioxidant, the phosphorus-based antioxidant as the secondary antioxidant and the sulfur-based antioxidant as the tertiary antioxidant. Polypropylene resin composition for a gate tube.

The method according to claim 1,
The first antioxidant is contained in an amount of 0.1 to 5 parts by weight,
The secondary antioxidant is included in an amount of 0.05 to 5 parts by weight
Wherein the third antioxidant is contained in an amount of 0.01 to 5 parts by weight based on 100 parts by weight of the polypropylene resin composition for a corrugated tube.

The method according to claim 1,
Wherein the polypropylene resin has a melt index of 0.1 to 3 g / 10 min (ASTM D1238, 2.16 kg, 230 DEG C).

The method according to claim 1,
Wherein the polypropylene resin is flocopolypropylene and the elongation is 300% or more.

The method according to claim 1,
Wherein the flame retardant is a halogen-based flame retardant, a hydrous inorganic compound-based flame retardant, or a phosphorus-based flame retardant.

The method according to claim 1,
The phenolic antioxidant may be 2,6-di-tert-butyl-4-methylphenol (BHT), thiodiethylene bis [2- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate, Songnox 1035), octadecyl- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, Songox1076), and tetrakis [ Methylene-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane (tetrakis ] methane). < / RTI >

The method according to claim 1,
The aromatic amine antioxidant may be at least one selected from the group consisting of phenylnaphthylamine, 4,4 '- (?,? - dimethylbenzyl) diphenylamine, and N, N'-di-2-naphthyl- And the polypropylene resin composition for a corrugated tube.

The method according to claim 1,
The phosphorus antioxidant may be at least one selected from the group consisting of tris (2,4-di-tert-butylphenyl) phosphite, tris (nonylphenyl) phosphite , TNPP), and di- (2,4-di-tert-butylphenyl) pentaerythritol diphosphite. Wherein the polypropylene resin composition is a polypropylene resin composition for a corrugated tube.

The method according to claim 1,
Wherein the sulfur-based antioxidant is at least one selected from the group consisting of di-stearyl thiodipropionate, ditridecyl thiodipropionate, and diaryl thiodipropionate. Resin composition.

A molded article produced from the polypropylene resin composition according to any one of claims 1 to 10.

12. The method of claim 11,
Wherein the molded article is a car corrugated tube.