KR20130052927A - Polyolefin graft copolymer and polyolefin-based resin composition using the same - Google Patents

Abstract

PURPOSE: A polyolefin graft copolymer is provided to have a stable structure and physical property by grafting a polyetherimide to a polyolefin, and to be grafted even at high temperature by a stable polyetherimide structure. CONSTITUTION: A polyolefin graft copolymer is that polyetherimide is grafted to a first polyolefin resin. The polyolefin graft copolymer is that the polyetherimide is grafted to the first polyolefin resin using a peroxide initiator as a catalyst. The graft ratio is 5-12 weight%. A polyolefin-based resin composition comprises the polyolefin graft copolymer and the second polyolefin resin.

Description

Polyolefin graft copolymer and polyolefin resin composition comprising the same

The present invention relates to a polyolefin graft copolymer and a polyolefin resin composition comprising the same. More specifically, the present invention relates to a polyolefin graft copolymer exhibiting sufficient adhesive strength even when directly coated without the treatment of a chlorine primer and a polyolefin resin composition comprising the same.

Since a material based on polyolefin resin has advantages such as excellent mechanical properties, processability and low cost, various products have been developed and applied to various applications. In particular, the use is expanding as a material for interior and exterior of automobiles. In particular, the usage is increasing as a material for automotive parts. In the case of automotive interior / exterior materials, good adhesion between the substrate and the paint is required because coating is essential for improving mechanical properties and aesthetic effects and surface properties.

However, since polyolefin resins such as polypropylene are nonpolar polymers, they have inferior adhesion to paints and thus have many difficulties in coating. Therefore, various surface pretreatment methods have been used to improve the paintability of materials based on polypropylene. One example is the use of chlorine primers prior to milling. However, chlorine-based primers represented by chlorinated polyethylene or chlorinated polypropylene cause environmental pollution and cost increase, and thus, various alternative techniques have been developed to avoid using them.

For example, surface treatment techniques using flame plasma instead of primer treatment have also been developed. This is a technique of improving the adhesive strength with the paint by oxidizing the surface of the molded product of the polypropylene composite material using a high temperature flame plasma to impart polarity. This has the disadvantage that additional expensive plasma processing equipment is required, and due to the characteristics of the plasma equipment, in the curved portion or the weld line formed during molding, the treatment effect may be insufficient or overprocessed to give uniform coating strength. Since it is difficult, there was a disadvantage in that it is difficult to obtain an excellent coating surface compared to the primer treatment.

On the other hand, as a technology for the development of a polypropylene-based composite material that does not require a primer treatment using a functional additive, Korean Laid-Open Patent Publication No. 2006-0092380 uses an acrylate functional polymer additive at 10 to 20% by weight. The method is introduced. However, by using a large amount of additives of 10 to 20% by weight, there is a problem that the smell or the physical properties of the polymer can be reduced as a whole and the paintability is insufficient when used in less than 10% by weight.

In addition, a polypropylene resin composition comprising a low molecular weight polypropylene resin modified with an unsaturated carboxylic acid or an acid anhydride is disclosed in Korean Patent Laid-Open No. 1999-0066058. However, functional groups alone, such as carboxylic acids or acid anhydrides, do not achieve sufficient paintability.

In order to solve the problems of the prior art as described above, an object of the present invention is to provide a polyolefin graft copolymer having a stable structure and physical properties by grafting polyetherimide to polyolefin.

In addition, an object of the present invention is to provide a polyolefin resin composition including the polyolefin graft copolymer described above, which can be directly coated without the treatment of a chlorine primer.

In order to achieve the above object, the present invention provides a polyolefin graft copolymer in which a polyetherimide is grafted to the first polyolefin resin.

According to one embodiment of the present invention, based on 100 parts by weight of the polyolefin graft copolymer, 60 to 99 parts by weight of the first polyolefin resin grafted with 0.5 to 39.9 parts by weight of polyetherimide with 0.02 to 7 parts by weight of a peroxide initiator as a catalyst It may be.

According to one embodiment of the present invention, the polyetherimide included in the polyolefin graft copolymer may be a compound represented by the following Chemical Formulas 1 to 4.

[Formula 1]

[Formula 2]

(3)

[Formula 4]

In the above Chemical Formulas 1 to 4,

R ₁ To R ₄ are each independently hydrogen or an alkyl group having 1 to 5 carbon atoms,

R ₅ is a saturated or unsaturated cycloalkyl group or phenyl group having 3 to 6 carbon atoms,

m is an integer from 0 to 10,

n is an integer from 1 to 100.

The present invention also provides a polyolefin resin composition comprising the polyolefin graft copolymer and the second polyolefin resin.

According to one embodiment of the invention, the second polyolefin resin is homo-polypropylene (Homo-polypropylene), polypropylene copolymer (Polypropylene compolymer), metallocene polypropylene (metallocene polypropylene), high melt strength polypropylene (High melt strength polypropylene), amorphous atactic polypropylene (atatic polypropylene) and thermoplastic polyolefin (Thermo plastic olefin, TPO) may be one or more selected from the group consisting of.

The polyolefin graft copolymers of the present invention are capable of sufficient graft reaction even at high processing temperatures due to the stable polyetherimide structure.

In addition, the polyolefin resin composition of the present invention containing the polyolefin graft copolymer includes a grafted modified polyolefin resin, thereby showing a high coating performance compared to a resin composition for direct coating performance used conventionally.

1 is a photograph of the coating property evaluation of the polyolefin resin composition according to Example 1 of the present invention.
2 is a photograph of evaluation of paintability of the polyolefin resin composition according to Example 2 of the present invention.
Figure 3 is a photograph of the paintability evaluation of the polyolefin resin composition according to Example 3 of the present invention.

The polyolefin graft copolymer of the present invention may be one in which polyetherimide is grafted to the first polyolefin resin. In addition, the polyolefin resin composition of the present invention may include the polyolefin graft copolymer and the second polyolefin resin.

Hereinafter, the polyolefin graft copolymer of the present invention and a polyolefin resin composition including the same will be described in detail. However, this is presented as an example for the present invention, by which the scope of the invention is not limited, it is apparent to those skilled in the art that various modifications to the embodiments can be made within the scope of the invention.

Unless otherwise stated throughout the specification, "including" or "containing" refers to the inclusion of other components (or components) without particular limitation, and refers to the addition of other components (or components) It is not to be interpreted as excluding.

Polyolefin Graft  Copolymer

In the polyolefin graft copolymer of the present invention, polyetherimide is grafted to the first polyolefin resin. At this time, it can be grafted with polyetherimide using a peroxide initiator as a catalyst.

According to an embodiment of the present invention, as the first polyolefin resin included in the polyolefin graft copolymer, a polypropylene homopolymer, an ethylene / propylene random copolymer, an ethylene / Propylene random copolymer (Ethylene / propylene block copolymer), ethylene / butene copolymer (Ethylene / butene copolymer), ethylene / octene copolymer ((Ethylene / octene copolymer) or ethylene / propylene / alpha-olefin terpolymer (Ethylene / propylene / α-olefin terpolymer) etc. When the ethylene / propylene random copolymer or the ethylene / propylene random copolymer is used as the first polyolefin resin, the ethylene content may be included in an amount of about 0.5 to about 20% by weight. Copolymers may be used, and when the ethylene / butene copolymer is used as the first polyolefin resin, the butene content is about 0.5 It may be a copolymer comprising from about 20% by weight.

The first polyolefin resin may be included in an amount of about 60 to about 99 parts by weight, preferably about 70 to about 95 parts by weight, based on 100 parts by weight of the polyolefin graft copolymer. When the first polyolefin resin is included in less than 60 parts by weight, the overall physical properties may decrease, and when included in excess of 99 parts by weight, the non-polarity may be strong and the paintability improvement effect may not be sufficient.

Melt index (Melt index, 230 ℃, 2.16kg) of the first polyolefin resin is not particularly limited, but may be about 0.5 to about 200g / 10min, preferably about 0.5 to about 100g / 10min.

In the polyolefin graft copolymer of the present invention, the polyetherimide grafted to the first polyolefin resin may be a maleimide compound.

The polyetherimide is grafted onto the first polyolefin resin to serve to introduce polarity into the non-polar first polyolefin resin.

According to one embodiment of the present invention, the polyetherimide may be represented by the following Chemical Formulas 1 to 4.

[Formula 1]

[Formula 2]

(3)

[Formula 4]

At this time, in the formula 1 to 4,

R ₁ To R ₄ are each independently hydrogen or an alkyl group having 1 to 5 carbon atoms,

R ₅ is a saturated or unsaturated cycloalkyl group or phenyl group having 3 to 6 carbon atoms,

m is an integer from 0 to 10,

n is an integer from 1 to 100.

According to one embodiment of the invention, preferably R ₁ To R ₄ are each independently hydrogen or a methyl group, and R ₅ is a saturated or unsaturated cycloalkyl group having 3 to 4 carbon atoms.

In one embodiment of the present invention, the polyolefin graft copolymer may be obtained by grafting a reactive polyetherimide represented by Chemical Formulas 1 to 4 having a double bond to the first polyolefin resin using a peroxide initiator. .

The reactive polyetherimide having a double bond does not ring open compared to maleic anhydride or maleic anhydride-modified polyolefin, and has stable structural characteristics, and thus exhibits high reactivity when graft reaction. According to the present invention, by using a reactive polyetherimide having a double bond in the graft reaction, there is no fear of decomposition at high temperatures or carbides during the reaction, showing a high graft yield.

The polyetherimide may be included in an amount of about 0.5 to about 39.9 parts by weight, preferably about 5 to about 30 parts by weight, based on 100 parts by weight of the polyolefin graft copolymer. When the polyetherimide is included in less than 0.5 parts by weight, the non-polarity imparted to the first polyolefin resin may be insufficient to improve the paintability. When the polyetherimide is included in excess of 39.9 parts by weight, unreacted materials remain and adhere. Performance may not come out.

The polyolefin graft copolymer of the present invention is obtained by carrying out a graft reaction with a peroxide initiator. In this case, the peroxide initiator is a compound that generates a radical in the first polyolefin resin to enable a reaction with a reactive polyetherimide having a double bond, and may be used as long as it is an initiator that can be commonly used for polymerization or copolymerization. For example, the peroxide initiator may be hydrogen peroxide, ketone peroxide, methyl ethyl ketone peroxide, cyclohexanone peroxide, methyl isobutyl ketone peroxide, diacyl peroxide, lauroyl peroxide, isobutyryl peroxide, acetyl peroxide, 2, 4-dichlorobenzoyl peroxide, succinic acid peroxide, decanoyl peroxide, diisononanoyl peroxide, perester, etc. are mentioned.

According to one embodiment of the invention, the peroxide initiator is preferably 2,5-dimethyl-2,5-di (t-butylperoxy) hexane (2,5-Dimethyl 2,5-Di (t-butylperoxy) ) hexane).

The peroxide initiator may be used in an amount of about 0.02 to about 7 parts by weight, preferably about 0.03 to about 6.0 parts by weight, and more preferably about 0.04 to about 5.0 parts by weight, based on 100 parts by weight of the polyolefin graft copolymer. When the content of the peroxide initiator is less than 0.02 parts by weight, it may be difficult for a sufficient graft reaction of the first polyolefin resin and the polyetherimide to occur, and it is preferable to keep it at 7 parts by weight or less in terms of securing a preferable process cost for the effect. Do.

The polyolefin graft copolymer according to one embodiment of the present invention may be polymerized by a reaction as in Schemes 1 to 4 below. The polymerization can be melt polymerized by, for example, injection of a first polyolefin resin into the main feeder using a twin screw extruder and extrusion of the polyetherimide into the extruder through a side feeder. 160 to about 230 ° C.

[Reaction Scheme 1]

[Reaction Scheme 2]

Scheme 3

[반응식 4]

[Reaction Scheme 4]

At this time, in the reaction scheme 1 to 4,

R ₁ To R ₄ And R ₆ are each independently hydrogen or an alkyl group having 1 to 5 carbon atoms,

R ₅ is a saturated or unsaturated cycloalkyl group or phenyl group having 3 to 6 carbon atoms,

l is an integer from 5 to 100,

m is an integer of 0 to 10,

n is an integer from 1 to 100.

On the other hand, the polyolefin graft copolymer of the present invention can be grafted further comprising an antioxidant. The antioxidant is an additive used to be able to act as a radical terminator. That is, it has the effect of suppressing excessive reaction of radicals generated by the peroxide initiator to lower the reaction rate. As the antioxidant, a phenol-based primary antioxidant or a phosphate-based secondary antioxidant such as IRGANOX 1010 or NA-11KY may be used.

In addition, the amount of the antioxidant may be about 0.05 parts by weight to about 1.0 parts by weight based on 100 parts by weight of the polyolefin graft copolymer. When the content of the antioxidant exceeds 1.0 parts by weight, mechanical properties may be deteriorated due to a decrease in weight average molecular weight due to excessive reaction of radicals generated by the peroxide initiator.

According to one embodiment of the invention, the graft ratio of the polyetherimide relative to the first polyolefin resin may be about 5% by weight or more, preferably about 5 to about 12% by weight. When grafted in the ratio of the above range, it is possible to achieve the optimum paint adhesion, less technical difficulties in the graft process.

Also, According to one embodiment of the invention, the polyolefin graft copolymer may have a weight average molecular weight (Mw) of about 30,000 to about 100,000, preferably about 3,500 to about 5,000.

The polyolefin graft copolymer of the present invention is capable of sufficient graft reaction even at high processing temperatures due to the stable polyetherimide structure, and improves paint adhesion when used in a polyolefin resin by using a polar polyetherimide in the polyolefin structure. Play a role.

Polyolefin series  Resin composition

The polyolefin resin composition of this invention contains the above-mentioned polyolefin graft copolymer and 2nd polyolefin resin.

Polypropylene may be used as the second polyolefin resin, and examples of the polypropylene include homo-polypropylene, polypropylene copolymer, metallocene polypropylene, and high melt melting. It may include one or more selected from the group consisting of high melt strength polypropylene, amorphous atactic polypropylene, and thermoplastic polyolefin (TPO). The high melt tension polypropylene resin is a resin having high melt tension by forming a long chain branch by applying electron beam crosslinking, reaction extrusion, and catalyst technology to a general polypropylene resin having a conventional linear structure. Refers to.

According to one embodiment of the present invention, when the high melt strength polypropylene is used as the second polyolefin resin, a polypropylene resin having a weight average molecular weight of about 123,000 or more, preferably about 123,000 to about 150,000 may be used. In addition, when the amorphous atactic polypropylene is used as the second polyolefin resin, a polypropylene resin having a weight average molecular weight of about 500,000 or more, preferably about 500,000 to about 600,000 and a molecular weight distribution of about 3.0 or more may be used.

Polypropylene is widely used in various industrial fields such as automobile interior / exterior parts or home appliance parts because of its light weight and excellent mechanical strength. In particular, polypropylene is used as a core molded product of a bumper or an instrument panel of an automobile. However, since polypropylene is a nonpolar polymer having a stable structure as a polymer to which several hundreds of thousands of hydrocarbons are regularly connected, adhesion to paint is inferior, which makes it difficult to paint.

Accordingly, the polyolefin resin composition of the present invention includes the polyolefin graft copolymer described above and has improved coating performance.

Detailed description of the polyolefin graft copolymer is as described above.

In the polyolefin resin composition of the present invention, the polyolefin graft copolymer and the second polyolefin resin may be included in a weight ratio of about 1: 5 to about 1: 25, preferably about 1: 9 to about 1: 20. When the polyolefin graft copolymer is included in less than 1: 5, it may not be sufficient to improve the paintability of the polyolefin-based resin composition of the present invention, it is not advantageous in terms of economics when it exceeds 1: 25.

In addition, the polyolefin resin composition of the present invention may further include known additives such as inorganic fillers such as glass fibers, talc, calcium carbonate, neutralizers, weather stabilizers, and antistatic agents. According to one embodiment of the present invention, the inorganic filler such as glass fiber may include about 20 to about 40% by weight based on the total weight of the polyolefin resin composition. By including the inorganic filler, physical properties of tensile strength, flexural strength, and impact strength may be improved.

By using the polyolefin resin composition of the present invention, by including a polyolefin graft copolymer that imparts polarity to the resin, the adhesion to the coating film is remarkably improved without lowering mechanical properties, so that the coating can be performed without treating the chlorine primer. Do. In addition, the stable structure of polyetherimide enables sufficient graft reaction even at high processing temperatures.

The invention is explained in more detail in the following examples. However, the following examples are illustrative of the present invention, and the present invention is not limited by the following examples.

<Examples>

Example  One

85% by weight of an ethylene / butene copolymer having a butene content of about 10% as the first polyolefin, and R ₁ , R ₂ in Formula 2 as polyetherimide Is hydrogen, R ₃ , R ₄ Is a methyl group, n is from 60 to 80 of 14% by weight of polyetherimide, and 1% by weight of 2,5-dimethyl-2,5 di (t-butylperoxy) hexane as the peroxide initiator is 40 mm, L / D = 52 A polyolefin graft copolymer was obtained by melt extrusion at a processing temperature of 160 to 230 ° C. using a twin screw extruder. The graft rate was 10-12% by weight.

A resin composition was prepared by mixing 95 wt% of TPO resin (GHE-300, Honam Petroleum) as the second polyolefin resin based on 5 wt% of the polyolefin graft copolymer.

Example  2

The resin composition was prepared in the same manner as in Example 1, except that 90 wt% of TPO resin (product name GHE-300, Honam Petroleum) was mixed as the second polyolefin resin with respect to 10 wt% of the polyolefin graft copolymer of Example 1. Prepared.

Example  3

70 weight% of PP resin (Product name HP-461Y, PolyMirae Co., Ltd.) as a 2nd polyolefin resin, and 25 weight% of SE-4121 2400tex (OCV Co., Ltd.) as glass fiber with respect to 5 weight% of polyolefin graft copolymers of Example 1. A resin composition was prepared in the same manner as in Example 1 except for mixing with.

The composition of Examples 1 to 3 is shown in Table 1 below.

Example 1 Example 2 Example 3 Polyolefin graft copolymer 5.0 wt% 10.0 wt% 5.0 wt% Second polyolefin resin 95.0 wt% (TPO) 90.0% by weight (TPO) 70.0% by weight (PP) Fiberglass - - 25.0 wt%

<Experimental Example>

Paintability  evaluation

The paintability of the resin compositions of Examples 1 to 3 was evaluated by the following method.

The resin composition obtained in Examples 1 to 3 was injection molded into a plate-shaped specimen of 110 mm × 70 mm × 3 mm at an injection temperature of 200 to 220 ° C. and a mold temperature of 30 ° C. using an injection molding machine. After spray coating with the paint used for the CIA, it dried for 30 minutes at 80 degreeC. The paintability of the coated specimens was evaluated by the Cross Cut test method.

That is, the specimens thus coated were cut into 2 × 2 mm horizontal and vertical checker boards in a square shape to make 100 pieces, and then the cellophane tape was sufficiently brought into close contact with each other, and then pulled out at high speed. At this time, the coating property was evaluated by converting the number of square grids remaining on the specimen as a percentage, and the results are shown in Table 2 below.

In addition, the photographs of the specimens in which the paintability of Examples 1 to 3 were evaluated by the above method are shown in FIGS. 1 to 3, respectively.

Example 1 Example 2 Example 3 Furtherance Second polyolefin resin 95.0 wt% (TPO) 90.0% by weight (TPO) 70.0% by weight (PP) Polyolefin graft copolymer 5.0 wt% 10.0 wt% 5.0 wt% Fiberglass - - 25.0 wt% Paintability Evaluation Paintability (%) 100 100 100

Referring to Table 2 and FIGS. 1 to 3, the resin composition including the polyolefin graft copolymer of the present invention showed excellent paintability of 100% in the evaluation results of paintability.

In addition, the physical properties of the resin compositions 1 and 2 were measured by the following method, and the results are shown in Table 3.

Melt Index ( MI )

It measured at 230 degreeC based on ASTMD1238.

The tensile strength

And measured at room temperature according to ASTM D638.

Flexural strength

And measured according to ASTM D790.

Izod  Impact strength

It measured according to ASTM D256.

Example 1 Example 2 Density (g / cm ³⁾ 0.97 0.97 The melt index (g / 10 min) 16.5 17.1 Tensile strength (kgf / cm ² ) 276 283 Flexural Strength (kgf / cm ² ) 396 396 Izod impact strength (kg cm / cm) 7.6 5.7

As described above, the resin composition of the present invention exhibited excellent physical properties.

Claims (15)

The polyolefin graft copolymer in which polyetherimide is grafted to 1st polyolefin resin.
The polyolefin graft copolymer according to claim 1, wherein the first polyolefin resin is grafted with polyetherimide using a peroxide initiator as a catalyst.
The polyolefin of claim 2, wherein 60 to 99 parts by weight of the first polyolefin resin is grafted to 0.5 to 39.9 parts by weight of polyetherimide based on 0.02 to 7 parts by weight of the peroxide initiator with respect to 100 parts by weight of the polyolefin graft copolymer. Graft copolymers.
The polyolefin graft copolymer of claim 1, wherein the polyetherimide is represented by the following Chemical Formulas 1 to 4.
[Formula 1]

(2)

(3)

[Chemical Formula 4]

In the above Chemical Formulas 1 to 4,
R ₁ To R ₄ are each independently hydrogen or an alkyl group having 1 to 5 carbon atoms,
R ₅ is a saturated or unsaturated cycloalkyl group or phenyl group having 3 to 6 carbon atoms,
m is an integer from 0 to 10,
n is an integer from 1 to 100.
According to claim 1, wherein the first polyolefin resin is a polypropylene homopolymer (Polypropylene homo-polymer), ethylene / propylene random copolymer (Ethylene / propylene random copolymer), ethylene / propylene block copolymer (Ethylene / propylene block copolymer) , Ethylene / butene copolymer (Ethylene / butene copolymer), ethylene / octene copolymer ((Ethylene / octene copolymer) And at least one polyolefin graft copolymer selected from the group consisting of ethylene / propylene / alpha-olefin terpolymers.
The method of claim 5, wherein the first polyolefin resin is a resin having a butene content of about 0.5 to about 20% by weight ethylene / butene copolymer or ethylene / propylene random copolymer or ethylene / propylene having a ethylene content of 0.5 to 20% by weight Polyolefin graft copolymer that is a block copolymer.
The polyolefin graft of claim 2 wherein the peroxide initiator is 2,5-dimethyl-2,5-di (t-butylperoxy) hexane (2,5-Dimethyl 2,5-Di (t-butylperoxy) hexane) Copolymer.
The polyolefin graft copolymer of claim 2, wherein the antioxidant is grafted to 0.05 parts by weight of 100 parts by weight of the polyolefin graft copolymer.
The polyolefin graft copolymer of claim 1, wherein the graft ratio of the polyetherimide to the first polyolefin resin is 5 to 12% by weight.
The polyolefin graft copolymer of claim 1 having a weight average molecular weight of 30,000 to 100,000.
The polyolefin graft copolymer of any one of claims 1 to 10; And
Polyolefin resin composition containing a second polyolefin resin.
The method of claim 11, wherein the second polyolefin resin is Homo-polypropylene, polypropylene copolymer, metallocene polypropylene, high melt strength polypropylene ), At least one polyolefin resin composition selected from the group consisting of amorphous atactic polypropylene and thermoplastic polyolefin (TPO).
The polyolefin resin composition of claim 11, wherein a weight ratio of the polyolefin graft copolymer and the second polyolefin resin is 1: 5 to 1:25.
The polyolefin resin composition of claim 11, wherein a weight ratio of the polyolefin graft copolymer and the second polyolefin resin is 1: 9 to 1:20.
The polyolefin resin composition according to claim 11, further comprising an inorganic filler.

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