Flame-retardant polyester resin composite composition and molded article manufactured from the same

Abstract

To provide a flame-retardant polyester resin composite composition which is excellent in balanced mechanical properties and hydrolysis resistance, and a molded article manufactured from the same.SOLUTION: A flame-retardant polyester resin composite composition contains 40 to 60 wt.% of (A) a polyester resin, 10 to 50 wt.% of (B) a glass fiber which is surface-treated with a sizing composition containing a film formation agent containing a polyurethane resin and an epoxy resin and a silane coupling agent containing aminosilane and epoxy silane, 10 to 30 wt.% of (C) a flame retardant having a phosphorus content of 20 wt.% or more and a nitrogen content of 5 wt.% or less, wherein when being measured in a 3:2 mixed solvent of phenol to o-dichlorobenzene at 25°C (weight reference), intrinsic viscosity of the polyester resin is 0.8 to 1.1 dl / g, or when being measured at 250°C and a load of 2.16 kg, a melting index of the polyester resin is 10 to 80 g / 10 min.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a flame-retardant polyester resin composite composition and a molded article produced therefrom. Specifically, the present invention relates to a flame-retardant polyester resin composite composition having an excellent balance of mechanical properties and hydrolysis resistance and a molded article produced therefrom.

Background Art

[0002] Polyester is a synthetic resin excellent in mechanical strength, heat resistance, transparency, and gas barrier properties, and is widely used as a material for beverage containers, packaging films, audio and video films, etc. Further, polyester is also widely used as a material for medical fibers, tire cords, building materials, etc.

[0003] In order to improve the mechanical or thermal properties of polyester, a filler such as glass fiber may be used together (see Patent Document 1). By the way, although the mechanical properties and heat resistance of a polyester resin composition reinforced with glass fiber are improved, there is also a problem that the color easily changes at high temperatures.

[0004] There have also been attempts to add a flame retardant to a polyester resin to improve flame retardancy and improve the adhesive strength with other members (see Patent Document 2).

[0005] On the other hand, since polyester resin is liable to undergo hydrolysis in a high-temperature and high-humidity environment, its scope of application is limited.

[0006] Therefore, there is a demand for the development of a flame-retardant polyester resin composite composition having an excellent balance of mechanical properties and hydrolysis resistance.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0008] An object of the present invention is to provide a flame-retardant polyester resin composite composition excellent in the balance of mechanical properties and hydrolysis resistance.

[0009] Another object of the present invention is to provide a molded article produced from the flame-retardant polyester resin composite composition.

Means for Solving the Problems

[0010] According to one embodiment of the present invention for achieving the above object, based on the total weight of the composition, (A) 40 to 60% by weight of a polyester resin, (B) a sizing composition containing a film-forming agent containing a polyurethane resin and an epoxy resin and a silane coupling agent containing an aminosilane and an epoxysilane, and 10 to 50% by weight of glass fiber surface-treated thereby, and (C) a flame retardant having a phosphorus content of 20% by weight or more and a nitrogen content of 5% by weight or less, 10 to 30% by weight, and when measured in a mixed solvent of phenol and o-dichlorobenzene at 3:2 (by weight) at 25°C, the intrinsic viscosity of the polyester resin is 0.8 to 1.1 dl / g, or when measured at 250°C under a load of 2.16 kg, the melt index of the polyester resin is 10 to 80 g / 10 min, a flame-retardant polyester resin composite composition is provided.

[0011] In a specific example of the present invention, the content of the polyester resin (A) may be 45 to 55% by weight, the content of the surface-treated glass fiber (B) may be 20 to 35% by weight, and the content of the flame retardant (C) may be 15 to 25% by weight.

[0012] In a specific example of the present invention, the polyester resin (A) may include at least one selected from the group consisting of polybutylene terephthalate (PBT) and polyethylene terephthalate (PET).

[0013] In a specific example of the present invention, the flame-retardant polyester resin composite composition may further include one or more additives (D) selected from the group consisting of antioxidants, weather stabilizers, release agents, dispersants, neutralizing agents, antiblocking agents, reinforcing materials, fillers, antistatic agents, lubricants, slip agents, nucleating agents, additional flame retardants, pigments, and dyes.

[0014] In a specific example of the present invention, the flame-retardant polyester resin composite composition may further include one or more antioxidants selected from the group consisting of pentaerythritol tetrakis(3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate), 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, and tris(2,4-di-t-butylphenyl) phosphite in a content of 0.05 to 0.3 parts by weight based on 100 parts by weight of the composition.

[0015] In a specific example of the present invention, the flame-retardant polyester resin composite composition may further include one or more lubricants selected from the group consisting of pentaerythritol tetrastearate and N,N'-ethylenebisstearamide in a content of 0.1 to 0.5 parts by weight based on 100 parts by weight of the composition.

[0016] According to another implementation example of the present invention, there is provided a flame-retardant polyester resin composite molded article manufactured by molding the flame-retardant polyester resin composite composition.

[0017] In a specific example of the present invention, the flame-retardant polyester resin composite molded article may satisfy the V0 standard when measured by the UL94 test method based on a thickness of 0.75 mm.

[0018] In a specific example of the present invention, the tensile strength after maintaining a flame-retardant polyester resin composite molded article of an ISO standard test piece at a temperature of 85°C and a relative humidity of 85% for 1000 hours can exhibit 85% or more of the initial tensile strength.

[0019] In a specific example of the present invention, the flame-retardant polyester resin composite molded article can be an automotive part or an electric and electronic part.

Effect of the Invention

[0020] The flame-retardant polyester resin composite composition according to an implementation example of the present invention is excellent in the balance of mechanical properties and hydrolysis resistance.

[0021] The polyester resin composite molded article according to an implementation example of the present invention can be usefully used for automotive parts and electric and electronic parts that may generate heat.

Mode for Carrying Out the Invention

[0022] Hereinafter, the present invention will be described in more detail. The flame-retardant polyester resin composite composition according to an implementation example of the present invention contains, based on the total weight of the composition, (A) 40 to 60% by weight of a polyester resin, (B) 10 to 50% by weight of glass fibers surface-treated with a sizing composition containing a film-forming agent containing a polyurethane resin and an epoxy resin and a silane coupling agent containing an aminosilane and an epoxysilane, and (C) 10 to 30% by weight of a flame retardant having a phosphorus content of 20% by weight or more and a nitrogen content of 5% by weight or less.

[0023] (A) Polyester resin The flame-retardant polyester resin composite composition according to an implementation example of the present invention contains a polyester resin (A).

[0024] In a specific example of the present invention, the polyester resin (A) may contain at least one selected from the group consisting of polybutylene terephthalate (PBT) and polyethylene terephthalate (PET). That is, the polyester resin (A) may contain either one or both of polybutylene terephthalate (PBT) and polyethylene terephthalate (PET).

[0025] Incidentally, polybutylene terephthalate (PBT) can be prepared by subjecting 1,4-butanediol and terephthalic acid or dimethyl terephthalate to an esterification reaction or a transesterification reaction, and then subjecting the product to polycondensation. Polyethylene terephthalate (PET) can be prepared by subjecting ethylene glycol and terephthalic acid or dimethyl terephthalate to an esterification reaction or a transesterification reaction, and then subjecting the product to polycondensation.

[0026] Also, when measured in a mixed solvent of phenol and o-dichlorobenzene at 3:2 (by weight) at 25°C, the intrinsic viscosity of the polyester resin (A) is 0.8 to 1.1 dl / g, or when measured at 250°C under a load of 2.16 kg, the melt index of the polyester resin (A) is 10 to 80 g / 10 min. When the intrinsic viscosity or melt index of the polyester resin (A) belongs to this range, the flame-retardant polyester resin composite composition can have appropriate processability and exhibit excellent mechanical properties.

[0027] The flame-retardant polyester resin composite composition according to an embodiment of the present invention contains the polyester resin (A) in a content of 40 to 60% by weight based on the total weight of the composition. Preferably, the flame-retardant polyester resin composite composition may contain the polyester resin (A) in a content of 45 to 55% by weight based on the total weight of the composition. If the content of the polyester resin (A) is less than 40% by weight, the mechanical properties and processability of the molded product may deteriorate, and if it exceeds 60% by weight, the processability and impact strength of the molded product may deteriorate.

[0028] (B) Glass fiber treated on the surface The flame-retardant polyester resin composite composition according to an embodiment of the present invention includes glass fibers (B) surface-treated with a sizing composition. Specifically, the flame-retardant polyester resin composite composition according to an embodiment of the present invention includes a film-forming agent containing a polyurethane resin and an epoxy resin, and glass fibers (B) whose surface is treated with a sizing composition containing an aminosilane and an epoxysilane. The glass fibers (B) surface-treated with the sizing composition can play a role in improving the mechanical strength and hydrolysis resistance of the flame-retardant polyester resin composite composition.

[0029] The glass fibers (B) surface-treated with the sizing composition used in the flame-retardant polyester resin composite composition according to an embodiment of the present invention may be those disclosed in Patent Document 1, but are not particularly limited thereto.

[0030] The flame-retardant polyester resin composite composition according to an embodiment of the present invention includes glass fibers (B) surface-treated with a sizing composition at a content of 10 to 50% by weight based on the total weight of the composition. Preferably, the flame-retardant polyester resin composite composition may include glass fibers (B) surface-treated with a sizing composition at a content of 10 to 40% by weight, more preferably 20 to 35% by weight, based on the total weight of the composition. When the content of the glass fibers (B) surface-treated with the sizing composition satisfies the above range, the flame-retardant polyester resin composite composition can exhibit excellent mechanical properties and hydrolysis resistance.

[0031] (C) Flame retardant The flame-retardant polyester resin composite composition according to an embodiment of the present invention includes a flame retardant (C). Specifically, the flame retardant (C) is a phosphorus-based flame retardant or a phosphorus-nitrogen-based flame retardant having a phosphorus content of 20% by weight or more and a nitrogen content of 5% by weight or less.

[0032] In a specific example of the present invention, the flame retardant (C) may include at least one phosphorus-based flame retardant or phosphorus-nitrogen-based flame retardant selected from flame retardants in which a polyphosphate-based and a melamine-based are combined.

[0033] The flame-retardant polyester resin composite composition according to an embodiment of the present invention contains a flame retardant (C) in a content of 10 to 30% by weight based on the total weight of the composition. Preferably, the flame-retardant polyester resin composite composition may contain the flame retardant (C) in a content of 15 to 25% by weight based on the total weight of the composition. When the content of the flame retardant (C) satisfies the above range, the flame-retardant polyester resin composite composition can have excellent mechanical properties and hydrolysis resistance, and can exhibit excellent flame retardancy.

[0034] (D) Additive The flame-retardant polyester resin composite composition according to an embodiment of the present invention may further contain ordinary additives within the scope not departing from the scope of the present invention. For example, the flame-retardant polyester resin composite composition according to an embodiment of the present invention may further contain one or more additives (D) selected from the group consisting of antioxidants, weather stabilizers, mold release agents, dispersants, neutralizing agents, antiblocking agents, reinforcing materials, fillers, antistatic agents, lubricants, slip agents, nucleating agents, additional flame retardants, pigments, and dyes, but is not particularly limited thereto.

[0035] In a specific example of the present invention, the flame-retardant polyester resin composite composition may further contain an antioxidant in order to improve its heat stability. As the antioxidant, phenolic antioxidants, phosphorus-based antioxidants, etc. can be used. Specifically, one or more antioxidants selected from the group consisting of pentaerythritol tetrakis(3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate), 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, and tris(2,4-di-t-butylphenyl)phosphite can be used.

[0036] In addition, the flame-retardant polyester resin composite composition may further contain the antioxidant in an amount of 0.05 to 0.3 parts by weight based on 100 parts by weight of the composition. If the content of the antioxidant is less than 0.05 parts by weight, it is difficult to ensure long-term heat resistance stability. On the other hand, even if the content of the antioxidant exceeds 0.3 parts by weight, the heat resistance stability will not be further improved, and the economy of the product may decrease, which is not desirable.

[0037] In a specific example of the present invention, the flame-retardant polyester resin composite composition may further contain a lubricant. Specifically, the flame-retardant polyester resin composite composition may further contain one or more lubricants selected from the group consisting of pentaerythritol tetrastearate and N,N'-ethylenebisstearamide in an amount of 0.1 to 0.5 parts by weight based on 100 parts by weight of the composition.

[0038] There are no particular restrictions on the method for preparing the flame-retardant polyester resin composite composition of the present invention, and the method for preparing a polyester resin composition known in the technical field to which the present invention belongs can be used as it is or appropriately modified. The above-described resin components and compounds can be freely selected and mixed in any desired order without any special order restrictions.

[0039] Specifically, for example, the above-mentioned resins and compounds are mixed with a required amount in a kneader such as a Hensel mixer, a kneader, a roll, or a Banbury mixer for 1 to 2 hours, and then melted and kneaded at a temperature of 200°C to 270°C using a single-screw / twin-screw extruder to prepare a pellet-shaped polyester resin composition.

[0040] According to another embodiment of the present invention, there is provided a flame-retardant polyester resin composite molded article manufactured by molding the flame-retardant polyester resin composite composition.

[0041] There are no particular restrictions on the method for manufacturing a molded article from the flame-retardant polyester resin composite composition according to the implementation examples of the present invention, and methods known in the technical field to which the present invention pertains can be used. For example, the flame-retardant polyester resin composite composition according to the implementation examples of the present invention can be molded by ordinary methods such as injection molding, extrusion molding, and casting molding to produce a flame-retardant polyester resin composite molded article. Preferably, a flame-retardant polyester resin composite molded article can be produced by injection molding the flame-retardant polyester resin composite composition.

[0042] In a specific example of the present invention, the flame-retardant polyester resin composite molded article can satisfy the V0 standard when measured by the UL94 test method based on a thickness of 0.75 mm.

[0043] In a specific example of the present invention, the tensile strength of the flame-retardant polyester resin composite molded article of the ISO standard test piece after being maintained at a temperature of 85°C and a relative humidity of 85% for 1000 hours can be 85% or more of the initial tensile strength.

[0044] In a specific example of the present invention, the flame-retardant polyester resin composite molded article can be used for automotive parts and electrical and electronic parts.

[0045] (Example) Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the following examples are only for illustrating the present invention, and the scope of the present invention is not limited thereto.

[0046] (Examples 1 and 2, Comparative Examples 1 to 6) The following resins and compounds were used in the contents shown in Table 1.

[0047] Glass fibers surface-treated with a sizing composition, a phosphorus-based flame retardant, and additives were added to a polyester resin, and melt-mixed in an extruder using a twin-screw extruder (75 mm, L / D 1:44) to pelletize a continuous resin composite to produce resin composition pellets. Next, after drying the resin composition pellets in a dryer at 120 °C for 4 hours, test injection specimens were produced using an Engel 180-ton injection molding machine.

[0048] At this time, pentaerythritol tetrakis(3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate) and 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene were used as antioxidants, and ethylene bisstearamide was used as a lubricant.

[0049] -A1: Polybutylene terephthalate (Kanghui, KH2100, intrinsic viscosity 1.0 dl / g) -A2: Polyethylene terephthalate (Lotte Chemical, BCN-80, intrinsic viscosity 0.85 dl / g) -B1: Glass fibers surface-treated with a sizing composition (KCC, CS329) -B2: Glass fibers (KCC, CS321) -C1: Phosphorus-based flame retardant (phosphorus content 23 wt%, nitrogen content 0 wt%) -C2: Phosphorus-nitrogen-based flame retardant (phosphorus content 21 wt%, nitrogen content 15 wt%) -C3: Phosphorus-nitrogen-based flame retardant (phosphorus content 19 wt%, nitrogen content 10 wt%) -C4: Phosphorus-zinc-based flame retardant (phosphorus content 19 wt%, nitrogen content 0 wt%) -C5: Phosphorus-nitrogen-based flame retardant (phosphorus content 23 wt%, nitrogen content 5 wt%) -C6: Aromatic bromine-based flame retardant (bromine content 50 wt%) and antimony trioxide (antimony trioxide 90 wt%) -D1: Hydrolysis inhibitor (carbodiimide) -D2: Hydrolysis inhibitor (ethylene-glycidyl methacrylate)

[0050]

Table 1

[0051] (Test Example) The flame-retardant polyester resin composite compositions obtained in each of the examples and comparative examples and the test pieces produced therefrom were tested by the following methods.

[0052] (1) Density Measured based on ISO 1183.

[0053] (2) Tensile Strength Measured based on ISO 527. The test pieces were prepared according to Type A, and the test speed was 50 mm / min.

[0054] (3) Flexural Modulus and Flexural Strength Measured based on ISO 178. The size of the test pieces was 80 mm × 10 mm × 4.0 mm, the span length was 60 mm, and the test speed was 2 mm / min.

[0055] (4) Izod Impact Strength Measured at room temperature according to ISO 180, Type A. The size of the test pieces was 80 mm × 10 mm × 4.0 mm, and notched test pieces were used.

[0056] (5) Heat Deflection Temperature (HDT) Measured based on ISO 75. The test piece size was 80 mm × 10 mm × 4.0 mm, and the stress load was 0.45 MPa.

[0057] (6) Hydrolysis Resistance The change rate of the tensile strength after maintaining at a temperature of 85 °C and a relative humidity of 85% for 1000 hours was measured.

[0058] (7) Flame Retardancy Measured by the UL94 test method.

[0059]

Table 2

[0060] As can be seen from Tables 1 and 2 above, the molded articles produced from the flame-retardant polyester resin composite compositions of the examples belonging to the scope of the present invention were all excellent in mechanical properties, hydrolysis resistance, and flame retardancy.

[0061] On the other hand, in the case of Comparative Example 1 using an aromatic bromine-based flame retardant and antimony trioxide, the flame retardancy decreased. In the case of Comparative Example 2 using a flame retardant with a nitrogen content outside the scope of the present invention, the flame retardancy and hydrolysis resistance decreased. In the case of Comparative Example 3 using a flame retardant with a nitrogen content outside the scope of the present invention and untreated glass fibers, the hydrolysis resistance decreased. In the case of Comparative Example 4 using a phosphorus-zinc-based flame retardant and untreated glass fibers, the flexural modulus, hydrolysis resistance, and flame retardancy decreased significantly. In the case of Comparative Examples 5 and 6 using untreated glass fibers and a hydrolysis inhibitor, the flexural modulus and flame retardancy decreased.

[0062] The molded articles produced from the flame-retardant polyester resin composite compositions according to the examples belonging to the scope of the present invention are excellent in the balance of mechanical physical properties and hydrolysis resistance, and thus can be usefully used for automotive parts and electric and electronic parts.

Claims

1. Based on the total weight of the composition, (A) 40 to 60% by weight of a polyester resin; (B) 10 to 50% by weight of glass fiber surface-treated with a sizing composition containing a film-forming agent containing a polyurethane resin and an epoxy resin, and a silane coupling agent containing an aminosilane and an epoxysilane; (C) 10 to 30% by weight of a flame retardant having a phosphorus content of 20% by weight or more and a nitrogen content of 5% by weight or less; The polyester resin has an intrinsic viscosity of 0.8 to 1.1 dl / g when measured in a mixed solvent of phenol and o-dichlorobenzene in a ratio of 3:2 (by weight) at 25°C, or a melt index of 10 to 80 g / 10 min when measured at 250°C under a load of 2.16 kg.

2. The content of the polyester resin (A) is 45 to 55% by weight, The content (B) of the surface-treated glass fiber is 20 to 35% by weight, The flame-retardant polyester resin composite composition according to claim 1, wherein the content of the flame retardant (C) is 15 to 25% by weight.

3. 2. The flame-retardant polyester resin composite composition according to claim 1, wherein the polyester resin (A) comprises at least one selected from the group consisting of polybutylene terephthalate (PBT) and polyethylene terephthalate (PET).

4. 10. The flame retardant polyester resin composite composition of claim 1, further comprising one or more additives (D) selected from the group consisting of antioxidants, weathering stabilizers, release agents, dispersants, neutralizing agents, antiblocking agents, reinforcing agents, fillers, antistatic agents, lubricants, slip agents, nucleating agents, additional flame retardants, pigments, and dyes.

5. The flame-retardant polyester resin composite composition according to claim 4, further comprising one or more antioxidants selected from the group consisting of pentaerythritol tetrakis(3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate), 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene and tris(2,4-di-t-butylphenyl)phosphite in an amount of 0.05 to 0.3 parts by weight based on 100 parts by weight of the composition.

6. The flame-retardant polyester resin composite composition according to claim 4, further comprising 0.1 to 0.5 parts by weight of one or more lubricants selected from the group consisting of pentaerythritol tetrastearate and N,N'-ethylene distearamide, based on 100 parts by weight of the composition.

7. A flame-retardant polyester resin composite molded product produced by molding the flame-retardant polyester resin composite composition according to any one of claims 1 to 6.

8. 8. The flame-retardant polyester resin composite molding according to claim 7, which satisfies the V0 standard when measured according to the UL94 test method with a standard thickness of 0.75 mm.

9. The flame-retardant polyester resin composite molding according to claim 7, wherein the tensile strength of an ISO standard test piece of the flame-retardant polyester resin composite molding after being maintained at a temperature of 85°C and a relative humidity of 85% for 1000 hours is 85% or more of the initial tensile strength.

10. The flame-retardant polyester resin composite molded article according to claim 7, which is an automobile part or an electric / electronic part.

Images