KR20050030689A - Polymer composition of polyester for metal deposition - Google Patents

Abstract

Provided is a thermoplastic polyester resin composition which is improved in metal deposition and is excellent in gloss after coating, moldability, durability, heat resistance and mechanical strength. The thermoplastic polyester resin composition comprises 100 parts by weight of a base resin comprising 40-80 parts by weight of a polybutylene terephthalate and 20-60 parts by weight of polyethylene terephthalate; 0.1-5.0 parts by weight of an epoxy-based resin stabilizer; 0.1-5.0 parts by weight of a pentaerythritol compound containing a long chain ester group; 0.1-10.0 parts by weight of an epoxy compound having at least two epoxy groups; 0-3 parts by weight of a silane compound having an organic functional group; and 2-35 parts by weight of glass fiber or an inorganic filler. Also the thermoplastic polyester resin composition comprises 100 parts by weight of a base resin comprising 40-80 parts by weight of a polybutylene terephthalate and 20-60 parts by weight of polyethylene terephthalate; 0.1-5.0 parts by weight of an epoxy-based resin stabilizer; 0.1-10.0 parts by weight of an epoxy compound having at least two epoxy groups; 0.1-3.0 parts by weight of a silane compound having an organic functional group; and 2-35 parts by weight of glass fiber or an inorganic filler.

Description

Thermoplastic Polyester Resin Composition Improved Vapor Deposition {Polymer Composition of Polyester for Metal Deposition}

Field of invention

The present invention relates to a polyester resin composition. More specifically, the present invention relates to a polyester resin composition excellent in paintability and surface adhesion and formability of a metal by aluminum deposition and excellent in gloss, durability, heat resistance and impact resistance after the coating and deposition process.

Background of the Invention

In general, polyethylene terephthalate (hereinafter referred to as "PET") resin is excellent in mechanical properties, chemical resistance, electrical properties and heat resistance, and is widely used in electrical and insulating parts, automobile parts, and the like. However, in view of the moldability, in order to improve this, crystallization behavior was improved by introducing a crystal nucleating agent and a crystallization promoter, thereby improving the moldability, thereby enabling molding at a normal mold temperature (80 to 100 ° C.). . However, the situation is not yet showing a smooth productivity and workability in the general molding machine.

On the other hand, polybutylene terephthalate (hereinafter referred to as "PBT") resin has a long-term heat resistance in comparison with PET resin, but the crystallization rate is faster, thereby increasing molding productivity. Continues to expand its scope of application. However, PBT has a high rate of crystallization, and thus, when a large amount of reinforcing agent is added, the surface protrusion of the reinforcing agent is a weak point.

On the other hand, PET resin has good mold release and good surface gloss while maintaining excellent properties, and high molding temperature conditions of about 130 ° C. are required in order to obtain a molded article maintaining various properties of PET. In the case of such high molding temperature conditions, the releasability is very bad, the surface is rough, there is no surface gloss, the crystallinity is very low, the crystallization rate is also slowed, the molding time is long. Therefore, a molded article having excellent release properties and surface properties can be obtained at a temperature of 130 ° C. or higher, but most of these are not easy because molding is often performed with water.

As a method for shortening the molding time of such PET, crystal nucleation agents and crystal growth agents are used. For example, US Pat. Nos. 3,435,093, 3,516,957, 4,357,268, 4,440,889, and British Patent 2,015,013. No. 2,015,014 discloses a molding nucleating agent and a crystal growth agent that can be formed at a molding temperature of 85 to 110 ° C. using a solid inert inorganic material and a group I or group II metal salt of mono or polycarboxylic acid. It is disclosed. Of course, this was limited to PET, and in order to have a sufficient effect, a large amount of nucleation agent and a crystal growth agent must be added, so there is a problem in that physical properties are deteriorated.

On the other hand, in the case of PBT, the crystallization rate is fast, and the moldability is quite excellent, but the mold release property is not very satisfactory. In particular, mold release defects are prominent on the metal surface of the resin. In order to improve the releasability of the adhesive resin, the mold cooling time needs to be long, and thus, the overall production cycle is long.

Conventional techniques for improving the moldability of polyester resins include U.S. Patent Nos. 4,380,621, 4,344,874, Japanese Patent Publication No. 54-38622, and Japanese Patent Publication No. 53-21757. Or higher fatty acid esters such as metal oxides, alkali metal salts, talc powder, paraffin and montanic acid were used to improve moldability. However, this also does not mention the technical details of kneading inorganic materials, glass fibers, additives, and the like, in particular, the expansion of the post-process such as painting, aluminum deposition has not been achieved.

In order to solve these problems, efforts are made to supplement the shortcomings of PBT resin and PET resin, and a large amount of products have been commercialized through the resin development by the PBT / PET alloy technique. However, through such a simple alloying technique, when painting as a post process such as painting or aluminum deposition is required, the surface is rough, the surface lacks glossiness, and an orange peel or a leveling defect occurs. In addition, in the case of a complicated molded product, the PBT / PET alloy can be difficult, but the molding process is difficult due to poor mold release.

In order to solve the problem of the polyester resin, the present inventors add a small amount of a silane compound having an organic functional group to the PBT / PET alloy to improve moldability, and have excellent glossiness and durability after coating processes such as painting and aluminum deposition. It has begun to develop a polyester resin composition excellent in heat resistance.

An object of the present invention is to provide a polyester resin composition excellent in paintability and evaporation properties during painting or aluminum deposition.

Another object of the present invention is to provide a polyester resin composition excellent in glossiness after a coating process.

Still another object of the present invention is to provide a polyester resin composition having excellent moldability.

Still another object of the present invention is to provide a polyester resin composition having excellent mechanical strength.

The thermoplastic polyester resin composition having improved deposition property according to the present invention comprises (A) 100 parts by weight of a basic resin consisting of 40 to 80 parts by weight of polybutylene terephthalate and 20 to 60 parts by weight of polyethylene terephthalate, and (B) an epoxy resin. 0.1 to 5.0 parts by weight of a stabilizer, (C) 0.1 to 5.0 parts by weight of a pentaerythritol compound containing a long chain ester group, (D) 0.1 to 10.0 parts by weight of an epoxy compound having two or more epoxy groups, (E) a silane having an organic functional group It is characterized by consisting of 0 to 3 parts by weight of the compound, and 2 to 35 parts by weight of (F) glass fiber or inorganic filler.

Further, the resin composition according to the present invention does not contain the pentaerythritol compound containing the long chain ester group as the component (C), but also contains the silane compound (E) having an organic functional group. It is possible to obtain a polyester resin composition having excellent properties, mechanical strength and the like.

The resin composition according to the present invention is a PTA / PET alloy (A) containing pentaerythritol containing a silane compound (E) or a long chain ester group having an organic functional group compatible with an inorganic substance and an organic substance. (pentaerythritol) A resin composition comprising a compound (C) and added in small amounts together with a catalyst and other additives. The pentaerythritol compound (C) containing the long chain ester group may be used together with the silane compound (E) having the organic functional group or may be used alone. In addition, the resin composition of this invention may use the said silane compound (E), without using the said pentaerythritol compound (C).

In the present invention, the other components are mixed based on 100 parts by weight of the base resin consisting of 40 to 80 parts by weight of the PBT and 20 to 60 parts by weight of PET.

As a stabilizer (B) used for the resin composition of this invention, phosphoric acid, phosphorous acid, phosphinic acid, phosphonic acid, a phosphonium compound, an imidazole compound, a trivalent amine, a tetravalent ammonium salt, etc. can be used. 0.1-5.0 weight part is used for the epoxy resin stabilizer (B) used for this invention.

The pentaerythritol compound (C) containing the long chain ester group used in the polyester resin composition according to the present invention may be used alone or in combination with the silane compound (E) having the organic functional group. In the case of using the pentaerythritol compound (C), epoxide wax is used together to obtain a composition having excellent paintability and deposition property in a post-process, and the content thereof is 0.2 to 2.0 parts by weight. If the content of the epoxide wax is less than 0.2 parts by weight, the effect of the additive is insignificant, and the gloss of the surface may be degraded even if release is possible. If the content of the epoxide wax exceeds 2.0 parts by weight, the gloss of the surface of the product is rather reduced due to gas generation.

When using Montan wax, the liquid epoxide additive should be added in an amount of 5 to 30% by weight based on 100% by weight of Montan wax. If the liquid epoxide additive is less than 5% by weight based on 100% by weight of Montan wax, When added, the untreated portion is generated due to the difference in the interfacial force with the coating agent during the post-processing, such as coating or deposition, and when added in excess of 30% by weight, the flow marks of the coating agent are severely generated due to the excessive interfacial force.

In the present invention, the content of the pentaerythritol compound (C) containing the long chain ester group is used in an amount of 0.1 to 5.0 parts by weight.

In the resin composition according to the present invention, an epoxy compound (D) having two or more epoxy groups is used. A synol type epoxy compound, a tetrahydroxy bisphenol F type epoxy compound, a cresol novolak type epoxy compound, a phenol novolak type epoxy compound, a cycloaliptic epoxy compound, etc. can be used. In this invention, 0.1-10.0 weight part of said epoxy compounds (D) are used.

The silane compound (E) having an organic functional group used in the present invention may be used alone or in combination with the pentaerythritol compound (C) containing the long chain ester group. The silane compound (E) having the organic functional group has a structure of Formula 1 below.

[Formula 1]

In the silane compound (E) having an organic functional group having the structure of Formula 1, alkyl or alkylate is substituted in the molecular chain. Here, when the silane compound having no functional group of alkyl or alkylate is used, the moldability is improved, but the glossiness is remarkably lowered due to the lack of compatibility of organic substances in a later process such as coating and deposition.

The silane compound (E) having the organic functional group used in the present invention uses 0.1 to 3.0 parts by weight based on 100 parts by weight of the PET and PBT blend base resin. If the content is less than 0.1 parts by weight, the effect of the addition is insufficient, and if it exceeds 3.0 parts by weight, the physical properties of the resin, such as impact resistance is considerably lowered, the viscosity is generated on the surface of the product is rather poor workability.

As described above, in the present invention, the pentaerythritol compound containing the long chain ester group and the silane compound (E) having the organic functional group may be used alone or in combination. In the present invention, by adding these compounds alone or in combination, the moldability which conventional polyester does not have is greatly improved, and it is not sensitive to the change in crystallization rate even when the crystallization rate is changed. Not only can it be remarkably improved, but the impact resistance is remarkably improved compared to conventional homogeneous resins.

Glass fiber or inorganic filler (F) used in the present invention is the same as the conventional PBT and PET alloy resin composition, for example, may include inorganic materials such as heat-resistant or talc, clay. In the present invention, it is used in the composition of 2 to 35 parts by weight.

The present invention will be further illustrated by the following examples, which are merely illustrative of the present invention and are not intended to limit or limit the scope of the present invention.

Examples 1-5 and Comparative Examples 1-4

In Examples 1 to 5 and Comparative Examples 1 to 4 according to the present invention, a chip obtained by melting and kneading a composition composed of the composition shown in Table 1 in a twin screw melt extruder heated to 240 to 280 ° C. was manufactured in a chip state. After drying at a temperature of 130 ° C. for at least 5 hours, the specimens were manufactured by using a screw-type injection machine heated to 240 to 280 ° C., and the mechanical properties of the specimens were evaluated, and the automobile headlamp bezel was formed to form a gloss after molding. Surface properties such as degree and roughness, paintability, and aluminum deposition property were evaluated. At this time, the headlamp bezel product used the SM3 application of Samsung Motors. All units are parts by weight.

Example Comparative Example One 2 3 4 5 One 2 3 4 (A) PBT / PET (2/1 weight% blend) 100 100 100 100 100 100 100 100 100 (B) Epoxy Resin Stabilizer 0.2 0.2 0.2 0.2 0.2 - - - - (C) pentaerythritol containing long chain ester groups 0.2 - 0.2 - 0.3 - - - - Montan Wax 0.3 0.3 0.3 0.3 0.3 - - - - Epoxide 0.02 - 0.02 - 0.03 - - - - (D) an epoxy compound having two or more epoxy groups 0.2 0.2 0.2 0.2 0.2 - - - - (E) alkylsilanes or alkylatesilanes 0.1 0.3 0.3 0.5 - - - - 4 (F) Heat-resistant 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Talc 30 30 30 30 30 30 30 30 30 Ethylene stearate - - - - - 0.3 - - - Silane - - - - - - - 0.3 -

The surface roughness of the injection specimen was measured for the specimen obtained in the composition as shown in Table 1, and the tensile strength, flexural strength, mold release property, paintability, aluminum deposition resistance, and impact resistance were evaluated, and the results are shown in the following Table 2 and Table 3 shows.

Here, the surface roughness of the molded article is a factor that has a decisive influence on the aluminum deposition property of the resin product applied to the automobile headlamp reflector mentioned in the present invention, but may be affected by the workability of the injection worker and the injection machine, but above all, the characteristics of the raw material of the resin. Depending on the surface characteristics are different. Factors representing surface roughness include R _a , R _t , and R _z , which are briefly described as follows.

R _a : Centerline average roughness

To note is the average height in central line of the first end face to the curve, and to display the symbol of R _a, CLA, AA is calculated by the equation (1).

[Reference Figure 1]

[Equation 1]

R _t : Maximum height roughness

As shown in Figure 2 below, the magnitude of roughness is represented by the vertical distance between two parallel lines that are parallel to the center line and pass through the highest and lowest points of the roughness curve within the cut-off of the specimen collection portion.

[Reference Figure 2]

R _z : Ten point median height roughness

As shown in Figure 2 below, the ISO roughness notation is represented by the distance between the average height from the highest peak to the fifth and the average valley depth from the lowest to the fifth. The ten-point average roughness R _z is obtained by the following equation.

[Reference Figure 3]

[Equation 2]

The numerical values of the comparison values shown in Tables 2 and 3 below can be obtained from the following measurement methods.

The surface roughness of the molded product was made by injecting a flat specimen of 10 cm in width and 10 cm in length with resin to make a coated specimen, and measuring the values of R _a , R _t , and R _z by Taylor Hobson Roughness Tester according to ISO roughness measurement standard. The illuminance level is indicated according to the following criteria.

Rt Rz Ra Roughness level Rt Rz Ra Roughness level -1.5 -1.7 -0.2 △△△△ -4.5 5.6 -0.5 △ -2.5 -3.0 -0.3 △△△ -5.5 -6.0 ～ 0.6 - -3.5 ～ 4.3 -0.4 △△

Tensile strength was measured according to ASTM D638, flexural strength was measured according to ASTM D790, mold release was measured by visual observation and effector pin marks during molding. The treatment state was visually confirmed and evaluated. The aluminum deposition property was measured by scratch test after vacuum deposition using an aluminum vapor deposition machine after the coating treatment. In addition, the impact resistance was subjected to FDI test to measure the height of the fracture of the specimen due to the impact.

Tensile strength (kgf / ㎠) Flexural Strength (kgf / ㎠) Mold release Paintability Aluminum depositability (%) Impact resistance (cm) 50% breaking height Example One 640 1050 ○ Good 0 42 2 635 1038 △ Good 3 38 3 652 1080 ○ Good 0 35 4 638 1105 △ Bad 10 31 5 651 1090 ○ Good 5 33 Comparative Example One 642 1107 ○ Good 3 33 2 638 1100 × Good 3 28 3 652 1201 ○ Good 0 38 4 640 1160 × Good 5 31

From the results of Table 3, it was found that the PBT / PET blend added with the organofunctional silane compound or the epoxide-added montan wax according to the present invention was excellent in releasability, paintability, and aluminum deposition property while taking advantage of each resin. Can be.

As can be seen from the above, when a small amount of organofunctional silane compound or epoxide-added montan wax is added to the PBT / PET blend, the moldability is improved while the paintability and gloss after the coating process such as aluminum deposition are excellent. A molded article excellent in durability, heat resistance and impact resistance can be obtained.

This invention has the effect of providing the polyester resin composition which is excellent in paintability and vapor deposition property at the time of painting or aluminum deposition, excellent glossiness after a coating process, and excellent moldability and mechanical strength.

Simple modifications and variations of the present invention can be readily used by those skilled in the art, and all such variations or modifications can be considered to be included within the scope of the present invention.

Claims (5)

(A) 100 parts by weight of a base resin consisting of 40 to 80 parts by weight of polybutylene terephthalate and 20 to 60 parts by weight of polyethylene terephthalate; (B) 0.1 to 5.0 parts by weight of an epoxy resin stabilizer; (C) 0.1 to 5.0 parts by weight of a pentaerythritol compound containing a long chain ester group; (D) 0.1 to 10.0 parts by weight of an epoxy compound having two or more epoxy groups; (E) 0 to 3 parts by weight of a silane compound having an organic functional group; And (F) 2 to 35 parts by weight of the glass fiber or inorganic filler; A thermoplastic polyester resin composition, characterized in that consisting of. (A) 100 parts by weight of a base resin consisting of 40 to 80 parts by weight of polybutylene terephthalate and 20 to 60 parts by weight of polyethylene terephthalate; (B) 0.1 to 5.0 parts by weight of an epoxy resin stabilizer; (D) 0.1 to 10.0 parts by weight of an epoxy compound having two or more epoxy groups; (E) 0.1 to 3.0 parts by weight of a silane compound having an organic functional group; And (F) 2 to 35 parts by weight of the glass fiber or inorganic filler; A thermoplastic polyester resin composition, characterized in that consisting of. The epoxy resin stabilizer (B) is selected from the group consisting of phosphoric acid, phosphorous acid, phosphinic acid, phosphonic acid, phosphonium compound, imidazole compound, trivalent amine, and tetravalent ammonium salt. Thermoplastic polyester resin composition, characterized in that. The epoxy compound (D) according to claim 1 or 2, wherein the epoxy compound (D) having two or more epoxy groups is a polyglycidyl ether compound, a polyglycidyl amine epoxy compound, a bisphenol A type epoxy compound, a bisphenol F type epoxy compound, or a resorcinol type. A thermoplastic polyester resin composition selected from the group consisting of an epoxy compound, a tetrahydroxy bisphenol F type epoxy compound, a cresol novolak type epoxy compound, a phenol novolak type epoxy compound, and a cycloaliphatic epoxy compound. The thermoplastic polyester resin composition according to claim 1 or 2, wherein the silane compound (E) having an organic functional group has a structure represented by the following general formula (1). [Formula 1]