KR19990052614A - Toughened Ethylene Propylene Block Copolymer / Polyamide Resin Composition - Google Patents

Abstract

The present invention relates to toughened ethylene propylene block copolymer / polyamide resin compositions in which mechanical strength and toughness are in harmony. The resin composition of this invention contains 60-90 weight% of ethylene propylene block copolymers, 10-40 weight% of polyamide resins, and 0-5 Phr of modified polypropylene. The polymer resin prepared from the resin composition of the present invention can be used in the manufacture of automobile parts, marine parts, aircraft parts, building materials, electrical parts, furniture, office equipment, and the like.

Description

Toughened Ethylene Propylene Block Copolymer / Polyamide Resin Composition

The present invention relates to toughened ethylene propylene block copolymer / polyamide resin compositions in which mechanical strength and toughness are in harmony. More specifically, the present invention relates to a resin composition comprising an ethylene propylene block copolymer / polyamide resin and a modified polypropylene.

In recent decades, polymer materials have made great strides in their kind and quantity, and have a great impact on daily life. As the industry develops, a variety of properties are required for polymer materials.Because of satisfying the properties required for materials by blending and combining existing polymers, it is advantageous in terms of economics such as cost reduction rather than synthesizing new polymers. In this respect, research on polymer blends is actively underway.

On the other hand, polypropylene is a semicrystalline thermoplastic polymer having a relatively low glass transition temperature, and is inexpensive, has excellent water resistance and insulation, low density and excellent processability, and can be given various physical properties through copolymerization with other monomers. On the other hand, there is an advantage in that it can be reinforced by adding an inorganic filler or toughened by adding rubber, whereas mechanical strength and heat resistance are insufficient, and printability and paintability are bad. In addition, polyamide is a polymer that has excellent mechanical and thermal stability such as tensile strength, flexural modulus and abrasion resistance, and has low permeability to organic solvents. There is a disadvantage in that the impact strength is lower and the price is slightly higher than the glass transition temperature. Therefore, by appropriately blending polypropylene and polyamide resins having such opposite properties, efforts have been made to develop polymer compositions that maintain their respective advantages and compensate for their disadvantages.

For example, US Pat. No. 5,140,059 discloses a method for blending polyamide with polypropylene modified with maleic anhydride to produce a polymer resin composition having relatively good mechanical strength. US Pat. No. 5,602,200 discloses polyamide / A method for producing a composition in which a kneaded state is uniformed by introducing a polypropylene modified with a carboxyl group or maleic anhydride as a compatibilizer into a polypropylene resin composition is disclosed. However, the polymer composition prepared by the foregoing methods has a relatively good water resistance and mechanical strength, but has a disadvantage of poor toughness. In order to compensate for this disadvantage, a method of preparing a polymer material having improved toughness by introducing ethylene propylene rubber into a polypropylene / polyamide resin composition has been developed (see J. Rosch, J. Appl. Polym. Sci). , 56: 1599-1605 (1995). However, the polymer resin composition prepared by this method also has improved toughness as compared to the conventional polymer composition, but has a disadvantage in that the physical properties of mechanical strength and toughness are poorly balanced.

Therefore, the need to overcome the limitations of the conventional polymer blend and to develop a polymer resin composition excellent in mechanical strength and toughness has been constantly emerging.

Accordingly, the present inventors have diligently studied to develop a polymer resin composition in which mechanical strength and toughness are improved in harmony. As a result, the polymer blend in which the polypropylene component in the conventional polypropylene / polyamide blend is replaced with an ethylene propylene block copolymer is mechanically modified. It was confirmed that both the strength and toughness are excellent, the present invention was completed.

After all, it is an object of the present invention to provide an ethylene propylene block copolymer / polyamide resin composition in which mechanical strength and toughness are harmonized.

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

The resin composition of this invention contains 60-90 weight% of ethylene propylene block copolymers, 10-40 weight% of polyamide resins, and 0-5 Phr of modified polypropylene. At this time, the ethylene content of the ethylene propylene block copolymer is 5 to 20% by weight, and polyamide resin is nylon 6, nylon 66 or nylon 12 and the like. In addition, the modified polypropylene serving as a compatibilizer for improving the interfacial adhesion between the ethylene propylene block copolymer and the polyamide is prepared by graft reaction of maleic anhydride to polypropylene, and the maleic anhydride content is 0.5 to 5% by weight.

The resin composition according to the present invention is prepared using a single screw or twin screw compressor by mixing the components together, preferably using a twin screw extruder to maximize the mechanical properties of the resin composition. In addition, the resin composition of the present invention may be a fibrous or particulate inorganic filler, a thermal stabilizer, a lubricant, a flame retardant, a colorant, an antistatic agent, a plasticizer, or the like, as necessary, within the scope of not impairing the object of the present invention. It can be suitably blended. The polymer resin prepared as described above may be used in the manufacture of automobile parts, marine parts, aircraft parts, building materials, electrical parts, furniture, office equipment, and the like.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are only for illustrating the present invention in more detail, it will be apparent to those of ordinary skill in the art that the scope of the present invention is not limited by these examples in accordance with the gist of the present invention. .

Example 1 Preparation of Resin Composition B-PP1 and Investigation of Mechanical Properties

70% by weight of an ethylene propylene block copolymer having an ethylene content of 6.5%, 30% by weight of a nylon 6 resin having a number average molecular weight of 22,000, and 1.9% by weight of a maleic anhydride modified polypropylene (Honam Petrochemical PH) -200 Grade) 2.5Phr mixed feed was fed to a Brabender compounding machine, which is a twin screw compressor, and blended under conditions of a cylinder temperature of 250 ° C. and a screw rotation speed of 60 rpm to prepare a resin composition B-PP1. Subsequently, the prepared blend was manufactured into specimens according to ASTM standards using an injection molding machine, and the mechanical strength of the specimens was measured using ASTM D-790 flexural modulus. The flexural modulus was measured and annealed for 40 hours at 23 ° C, 50% relative humidity and constant temperature and humidity, and then at 25mm / min crosshead speed on a universal testing machine (Instron, model name 6022). Was carried out. Toughness was measured using ASTM D-256 Izod Notched impact strength. On the other hand, the impact strength was measured and annealed for 40 hours at 23 ° C., 50% relative humidity, and constant temperature and humidity conditions, and then using an Izod impact tester (Model Toy 612, Model 612). The results are shown in Table 1 below.

Example 2 Preparation of Resin Composition B-PP2 and Investigation of Mechanical Properties

A polymer resin composition (B-PP2) and a specimen were prepared in the same manner as in Example 1, except that Example 1 used an ethylene propylene block copolymer having an ethylene content of 8.7% by weight, and mechanical properties were investigated. (Table 1). As shown in Table 1 below, as the ethylene content of the ethylene propylene block copolymer is increased than in Example 1, the strength was decreased, but the toughness was improved.

Example 3 Preparation of Resin Composition B-PP3 and Investigation of Mechanical Properties

Except for using the ethylene propylene block copolymer having an ethylene content of 12.6% by weight in Example 1, the polymer resin composition (B-PP3) and the specimens were prepared in the same manner as in Example 1, and the mechanical properties were investigated. (See Table 1). As shown in Table 1 below, as the ethylene content of the ethylene propylene block copolymer is increased than in Example 1, the strength was decreased, but the toughness was improved.

Example 4 Preparation of Resin Composition B-PP4 and Investigation of Mechanical Properties

Except that the ethylene propylene block copolymer having an ethylene content of 14.7% by weight in Example 1, the polymer resin composition (B-PP4) and the specimens were prepared in the same manner as in Example 1, and mechanical properties were examined ( See table 1). As shown in Table 1 below, as the ethylene content of the ethylene propylene block copolymer is increased than in Example 1, the strength was decreased, but the toughness was improved.

Comparative Example 1 Preparation of Resin Composition EPR1 and Investigation of Mechanical Properties

In the same manner as in Example 1, except that in Example 1, instead of 70% by weight of ethylene propylene block copolymer, 64.2% by weight of polypropylene homopolymer and 5.8% by weight of ethylene propylene rubber having an ethylene content of 78% by weight were introduced. Polymer resin composition (EPR1) and specimens were prepared, and mechanical properties were examined (see Table 1). As shown in Table 1 below, it was found that the toughness is lower than that of the ethylene propylene block copolymer.

Mechanical Properties of Various Resin Compositions Resin composition Flexural modulus (kg / ㎠) Impact strength (kg ㎝ / ㎝) B-PP1 17,900 11.2 B-PP2 17,700 13.5 B-PP3 17,000 16.0 B-PP4 16,400 19.1 EPR1 17,900 10.5

As described and demonstrated in detail above, the present invention relates to a resin composition comprising an ethylene propylene block copolymer, a polyamide resin, and a modified polypropylene. The resin composition of the present invention can improve the toughness without decreasing the strength by replacing the polypropylene with the ethylene propylene block copolymer in the conventional polypropylene / polyamide blend, and increase the ethylene content of the ethylene propylene block copolymer By increasing the toughness can be increased. The polymer resin prepared from the resin composition of the present invention can be used in the manufacture of automobile parts, marine parts, aircraft parts, building materials, electrical parts, furniture, office equipment, and the like.

Claims (5)

60 to 90 weight percent of ethylene propylene block copolymer; 10 to 40% by weight of polyamide resin; And, Ethylene propylene block copolymer / polyamide resin composition containing modified polypropylene 0-5 Phr. The method of claim 1, Ethylene content of the ethylene propylene block copolymer, characterized in that 5 to 20% Ethylene Propylene Block Copolymer / Polyamide Resin Composition. The method of claim 1, The polyamide resin is characterized in that the material selected from the group consisting of nylon 6, nylon 66 and nylon 12 Ethylene Propylene Block Copolymer / Polyamide Resin Composition. The method of claim 1, The modified polypropylene is produced by graft reaction of maleic anhydride 0.5 to 5% by weight Ethylene Propylene Block Copolymer / Polyamide Resin Composition. Ethylene propylene block copolymer / polyamide resin composition according to claim 1, further comprising at least one substance selected from the group consisting of inorganic fillers, heat stabilizers, lubricants, flame retardants, colorants, antistatic agents and plasticizers. Coalescing / Polyamide Resin Composition.