KR100652968B1 - Polyphenylenesulfide/polyamide resin compositions suitable for high temperature pigment coating process - Google Patents

Abstract

Provided are a polyphenylene sulfide/polyamide resin composition for profile extrusion which is remarkably improved in melt strength, thermal stability and process stability without the deterioration of heat resistance and can be powder painted at a high temperature, and a molded product prepared from the composition. The polyphenylene sulfide/polyamide resin composition comprises (A) 50-70 parts by weight of a polyphenylene sulfide resin; (B) 30-50 parts by weight of a polyamide resin; (C) 0.5-2 parts by weight of an acryl-modified polytetrafluoroethylene based on 100 parts by weight of a base resin (A)+(B); and (D) 10-50 parts by weight of a glass monofilament based on 100 parts by weight of (A)+(B)+(C). Preferably the polyphenylene sulfide resin is a linear polyphenylene sulfide resin containing 70 mol% or more of a phenylene sulfide structural unit.

Description

Polyphenylenesulfide / Polyamide Resin Compositions Suitable for High Temperature Pigment Coating Process}

Field of invention

The present invention relates to a polyphenylene sulfide / polyamide resin composition. More specifically, the present invention relates to a polyphenylene sulfide / polyamide resin composition, which enables a stable and continuous extrusion process by dramatically increasing the melt tension while maintaining excellent heat resistance.

Background of the Invention

PPS (Poly phenylenesulfide) resin is a crystalline resin and is a high functional resin having high mechanical strength, excellent chemical resistance, and excellent heat resistance. If you want to apply this excellent PPS to Profile bars or Profile spacers, Pipes, Sheets, Fibers, etc., use the profile extrusion or fiber spinning process. It should be applied, due to the inherent fast crystallization temperature, low viscosity value and low melt strength (PPS) has a disadvantage of making this difficult.

Glass fiber-reinforced polyamide (PA) material, which is typically used for extrusion, is an economical material compared to PPS, but due to its high absorption rate and low heat resistance, warpage occurs when the processed profile extruded product is subjected to high temperature powder coating, which is a post process There is a fundamental problem.

In the case of profile bar shape, its application range is wide and its usage is quite high, such as spacers or interior / kitchen building materials, which are internal insulation materials such as window frames. Polyamide 66 is currently widely used, but polyamide may cause deterioration of physical properties due to high hygroscopic properties or thermal deformation at high temperatures in the coating / plating process. In general, it is known that when processed at 220 ° C. or higher, warpage deformation frequently occurs due to thermal deformation and evaporation of moisture contained in a small amount in the resin.

In the case of pipe water, there are many application ranges such as water, chemical solvent, air, oil, and the like. In particular, in order to serve as a chemical solvent, there is a problem in that a resin having excellent chemical resistance needs to be applied.

Sheets are used in applications such as containers using vacuum forming and hot pressing methods. In particular, suitable resins should be used for containers requiring chemical or heat resistance.

For many of these applications, PPS with good mechanical strength, chemical resistance, and heat resistance can be useful, but due to the fast crystallization temperature, low viscosity, and melt tension mentioned above, profile rod shapes, pipe water and sheet shapes are produced. There is a difficulty in the extrusion process. Application of common PPS to extrusion processes results in shaping problems due to fast crystallization temperatures, sagging or deformation of melt extrudate due to low viscosity and high tan δ, and tearing and breaking of melt extrudate due to low melt tension. Problems may be caused.

In order to overcome this, US Patent No. 5,573,823 discloses a method of using a copolymer of PPS and BPS (Biphynylene sulfide) in preparing pipe water. The PPS / BPS copolymer gives toughness to the PPS and at the same time lowers the crystallinity, thereby making the pipe water possible.

In addition, in US Patent No. 5,507,984, in the step of using the extrusion process after dissolving PPS in a solvent during the Membrane manufacturing process, the PPS is heat-treated at 200 ℃, oxygen atmosphere to increase the viscosity of the PPS consequently extrudeability of PPS solution It discloses a method of making excellent.

In Japanese Patent Laid-Open Publication No. 2003-2175, EGMA (Ethylene-glycidiyl methacrylate) and EGMA are used as the materials used when manufacturing different types of resins in several layers to improve the barrier performance of pipes used in cooling water systems. An invention is disclosed in which a PPS resin obtained by blending 20 to 40% of an ethylene-propylene copolymer and a resin obtained by alloying 10 to 45% by weight of nylon with PPS in different layers is disclosed.

However, even when applied to the extrusion process using the PPS resin compositions invented as described above, the melt tension of the PPS resin composition is still low, there is a lack of a continuous and stable process.

Accordingly, the present inventors have blended polyamide, acryl-modified polytetrafluoroethylene, and short glass fibers in a PPS resin composition to maintain excellent heat resistance and dramatically increase melt tension to enable a stable and continuous extrusion process. It is early to develop a polyamide resin composition.

An object of the present invention is to provide a polyphenylene sulfide / polyamide resin composition having excellent heat resistance.

It is another object of the present invention to provide a polyphenylene sulfide / polyamide resin composition which is capable of dramatically increasing the melt tension to enable a stable and continuous extrusion process.

Another object of the present invention is to provide a polyphenylene sulfide / polyamide resin composition having excellent high temperature powder coatability.

Another object of the present invention is to provide a polyphenylene sulfide / polyamide resin composition having excellent flexural strength and extrusion appearance.

Both the above and other objects of the present invention can be achieved by the present invention described below.

Summary of the Invention

The present invention (A) 50 to 70 parts by weight of polyphenylene sulfide resin; (B) 30-50 parts by weight of polyamide resin; (C) 0.5 to 2 parts by weight of acrylic modified polytetrafluoroethylene based on 100 parts by weight of the base resin of (A) + (B); And (D) 10 to 50 parts by weight of short glass fibers with respect to 100 parts by weight of the (A) + (B) + (C), while maintaining excellent heat resistance, significantly increasing the melt tension and stable and continuous extrusion process The present invention relates to a polyphenylene sulfide / polyamide resin composition which is possible.

Detailed Description of the Invention

The polyphenylene sulfide / polyamide resin composition of the present invention comprises (A) 50 to 70 parts by weight of polyphenylene sulfide resin; (B) 30-50 parts by weight of polyamide resin; (C) 0.5 to 2 parts by weight of acrylic modified polytetrafluoroethylene based on 100 parts by weight of the base resin of (A) + (B); And (D) 10 to 50 parts by weight of short glass fibers, based on 100 parts by weight of (A) + (B) + (C).

Hereinafter, the detailed description about each component of the polyphenylene sulfide / polyamide resin composition of this invention is as follows.

(A) polyphenylene sulfide (PPS) resin

As the polyphenylene sulfide resin capable of a preferred profile extrusion and fiber spinning process for use in the present invention, a linear type polyphenylene resin containing 70 mol% or more of repeating units represented by the following general formula (1) is used. It is because the content of the said repeating unit containing 70 mol% or more is high in crystallinity which is the characteristic of a crystalline polymer, and is excellent also in heat resistance, chemical resistance, and strength.

[Formula 1]

The polyphenylene sulfide resin is known to have a linear molecular structure having no branched or crosslinked structure or a molecular structure having branched or crosslinked structure depending on the production method thereof. In the present invention, a linear polyphenylene sulfide resin having no linearly branched or crosslinked structure is used. If the polyamide resin and the crosslinked polyphenylene sulfide resin are blended, not only the natural color of the resin becomes brown, but also a problem that the impact strength and the extrusion characteristics decrease. A typical method for producing the linear polyphenylene sulfide resin is disclosed in Japanese Patent Laid-Open No. 52-12240.

The polyphenylene sulfide resin of the present invention may include other copolymerized structural units represented by the following Chemical Formulas 2 to 9 of less than 50 mol%, preferably less than 30 mol%.

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

[Formula 7]

(Wherein R is an alkyl group, nitro group, phenyl group, alkoxy group, carboxyl group or metal carboxylate group)

[Formula 8]

[Formula 9]

There are known methods to enable the profile extrusion process and fiber spinning process using the polyphenylene sulfide resin. For example, all of the PPS resin composition technology that adjusts the viscosity and crystallization rate is the same, the polyphenylene sulfide resin composition is a method of increasing the molecular weight by heat treatment at 200 ℃, oxygen atmosphere. However, when manufacturing in this way, the reaction time is long, the productivity is lowered, there is a burden that the manufacturing cost of PPS increases. In addition, the ease of adjusting the melt tension, which is a major factor in the expression of the extrusion characteristics of the resin, is reduced according to the use. As a blending method, there is a method of adding an EGMA-based TPE (Thermoplastic elastomer), but the heat resistance and rigidity of the PPS are lowered, and it is difficult to expect a significant expression of melt tension. A detailed method can be found in US Patent No. 5,507,984, Japanese Patent Application Laid-Open No. 2003-2175, and the like. In the present invention, not limited to the PPS, it is possible to apply a low viscosity PPS that is easily produced by a general reaction process.

In the present invention, the polyphenylene sulfide resin is preferably used in 50 to 70 parts by weight. If it is more than 70 parts by weight, the melt tension may be lowered, and if it is less than 50 parts by weight, heat resistance may be reduced.

(B) polyamide resin

As the polyamide resin used in the present invention, all of polyamide 6, polyamide 66, polyamide 12, and the like may be applied. However, in consideration of economical efficiency, polyamide 6 is preferably applied. In the case of applying polyamide 6, the viscosity is not particularly limited, but low viscosity polyamide 6 having an intrinsic viscosity of 1.6 to 2.2 dl / g that can be used for injection is more preferable.

In the present invention, the polyamide resin is preferably used at 30 to 60 parts by weight based on PPS. If it exceeds 60 parts by weight, it is difficult to express heat resistance of PPS, and if it is less than 30 parts by weight, the economical efficiency of the PPS resin composition is significantly lowered.

(C) acrylic modified polytetrafluoroethylene (A-PTFE)

A-PTFE used in the present invention is a product already commercialized by Mitsubishi Rayon Co., Ltd., which introduces acrylic groups to polytetrafluoroethylene having a molecular weight of millions or more to improve compatibility with resins blended to form a PTFE-like PTFE chain. It is a principle to effectively disperse the resin and improve the melt tension of the resin. In the resin formulation, 0.5 to 2 parts by weight is preferable with respect to 100 parts by weight of the base resin of (A) + (B), and more preferably within 1 part by weight. At 2 parts by weight or more, there is no further increase in melt tension, that is, an improvement in extrusion processability, and the appearance becomes rough due to excessive use, and, in severe cases, phase separation occurs, resulting in deterioration in impact properties of the resin. If less than 0.5 parts by weight, the effect of improving the melt tension is insignificant.

(D) short glass fiber

In consideration of processability and appearance characteristics, the short glass fibers used in the present invention preferably use short fibers of 1.5 to 4.5 mm in length, and more preferably short fibers of 3 mm in length. In order to obtain desired heat resistance, it is preferable to use 10-50 weight part with respect to 100 weight part of said (A) + (B) + (C). If it is less than 10 parts by weight, the increase in physical properties is extremely small, and if it is more than 50 parts by weight, short glass fibers may protrude to the surface of the resin, which may result in severe appearance damage and degradation of extrusion stability.

In addition to the above components, the thermoplastic resin composition of the present invention may be appropriately added an antioxidant, a mold release agent, a flame retardant, a lubricant, a colorant such as a pigment or a dye, a small amount of multiple polymers, and the like.

The resin composition of this invention can be manufactured by the well-known method of manufacturing a resin composition. For example, the components of the present invention and other additives may be mixed simultaneously, then melt extruded in an extruder and made into pellets.

The invention can be better understood by the following examples, which are intended for the purpose of illustration of the invention and are not intended to limit the scope of protection defined by the appended claims.

Example

(A) polyphenylene sulfide resin, (B) polyamide resin, (C) acrylic modified polytetrafluoroethylene and (D) glass used in Examples 1-3 and Comparative Examples 1-3 of Table 1 below The production and specifications of short fibers are as follows.

(A) polyphenylene sulfide resin (PPS)

In the PPS resin composition used in the present invention, PPS used the brand name KL-02G of Japan DIC Co., Ltd., whose melt index (MFI) had a value of 48 to 70 g / 10 min at a load of 316 ° C and 1270 g.

(B) polyamide resin (PA6)

Kolon KN-170, Polyamide 6 was used.

(C) acrylic modified polytetrafluoroethylene (A-PTFE)

Mitsubishi Rayon (MRC) A-3000 was used.

(D) Short glass fiber (SGF)

Vetrotex short fibers (3 mm, diameter 12 micron) was used.

Examples 1-3 and Comparative Examples 1-3

Using the above-mentioned components, the same resin compositions as those shown in Examples 1 to 3 and Comparative Examples 1 to 3 of Table 1 were prepared, and their melt tension and physical properties are also shown in Table 1.

Each component was mixed with the composition shown in Table 1 above, followed by mixing in a conventional mixer. Then, it fed into the twin screw extruder of L / D = 36 and k = 45 mm. The mixture was prepared into a resin composition in pellet form through an extruder, and a specimen for measuring melt tension and an ASTM standard for measuring physical properties at an injection temperature of 300 ° C. were prepared using a 10 oz injection machine. The prepared specimens were left at 23 ° C. and 50% relative humidity for 40 hours to evaluate their physical properties.

Property evaluation method

(1) Melt tension: Each specimen was left at 23 ℃ for 48 hours at 50% relative humidity, and melt tension was 1.5mm thick, 6mm wide and 60mm long, and Rheometric Scientific RME was used for a temperature of 290 ℃, The strength at the time of breaking the specimen at the extensional rate of 0.5 [s ^-1 ] was measured.

(2) Flexural Strength: Flexural strength and flexural modulus were measured according to ASTM D790.

(3) Hot powder coating: A strip having a thickness of 2 mm and a length of 500 mm was produced by an extruder with a T-Die, and then put into a laboratory powder coating facility designed separately. After the temperature was raised to 220 ° C., the coating pigment powder was scattered and allowed to stand for 3 minutes to adhere to the surface of the strip. The temperature was cooled to 50 ° C. and left for 5 minutes, and then the specimens were taken out. The uniformity of the coating and the presence or absence of deformation of the strip were visually observed to identify good or bad. A total of five specimens were prepared according to each condition and reflected in the determination.

(4) Heat Deflection Temperature: Measured according to ASTM D 648.

(5) Extrusion workability: The degree to which the shape of the sheet was easily produced was evaluated.

Example Comparative Example One 2 3 One 2 3 (A) polyphenylene sulfide resin (A / (A + B + C) * 100) 69 69 60 69 69 40 (B) Polyamide Resin (B / (A + B + C) * 100) 30 30 40 30 30 60  (C) acrylic modified polytetrafluoroethylene (C / (A + B + C) * 100) One One One - - One (D) Short glass fiber (D / (A + B + C + D)) 30 50 30 30 60 30 Heat deflection temperature (℃, 18.6 kg) 245 250 242 243 251 215 Flexural Strength [kgf / ㎠] 97,000 150,500 94,000 97,500 160,000 88,000 Melt Tension [Pa] 115,200 123,200 105,500 20,500 18,900 118,800 Extrusion workability Good Good Good Bad Bad Good Extrusion appearance Good usually Good Good Bad Good Deformation specimen after high temperature powder coating (based on 5 specimens) 0 0 0 4 4 3

As shown in Table 1, in the case of Examples 1 to 3 and Comparative Example 3 in which A-PTFE was used in 1 part by weight, extrusion workability was very good, but Comparative Example 1 and A-PTFE were not added. In the case of 2, normal extrusion is impossible. The same is reflected in the numerical value of the melt tension, and the melt tension of the compositions capable of extrusion work showed high values of 100,000 Pa or more. In Comparative Examples 1 and 2 with low melt tension, the strip was frequently broken during profile extrusion, so that continuous profile molding was impossible.

On the other hand, when the amount of polyamide resin used is too high, as in Comparative Example 3, extrusion workability is excellent, but polyamide occupies the main component of the resin, and thus deformation after high-temperature powder coating occurs frequently due to low heat resistance even after glass short fiber reinforcement. Appeared.

The present invention is composed of polyphenylene sulfide resin, polyamide resin, acrylic modified polytetrafluoroethylene and short glass fibers, significantly improved thermal stability and processing stability, high temperature powder coating polyphenylene sulfide / It has the effect of providing the polyamide resin composition.

Simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

Claims (6)

(A) 50 to 70 parts by weight of polyphenylene sulfide resin; (B) 30-50 parts by weight of polyamide resin; (C) 0.5 to 2 parts by weight of acrylic modified polytetrafluoroethylene based on 100 parts by weight of the base resin of (A) + (B); And (D) 10 to 50 parts by weight of short glass fibers, based on 100 parts by weight of (A) + (B) + (C); Polyphenylene sulfide / polyamide resin composition comprising a. The polyphenylene sulfide / polyamide resin composition according to claim 1, wherein the polyphenylene sulfide resin is a linear polyphenylene resin containing 70 mol% or more of phenylene sulfide structural units. The polyphenylene sulfide / polyamide resin composition according to claim 1, wherein the polyphenylene sulfide resin further comprises other copolymerization structural units represented by the following Chemical Formulas 2 to 9 in less than 50 mol%. [Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

[Formula 7]

(Wherein R is an alkyl group, nitro group, phenyl group, alkoxy group, carboxyl group or metal carboxylate group) [Formula 8]

[Formula 9]

The polyphenylene sulfide / polyamide resin composition according to claim 1, wherein the polyamide resin is selected from the group consisting of polyamide 6, polyamide 66, and polyamide 12. The polyphenylene sulfide / polyamide resin composition according to claim 1, wherein the acryl-modified polytetrafluoroethylene has an acryl group introduced into the polytetrafluoroethylene. A molded article processed with the resin composition according to any one of claims 1 to 5.