KR20110076272A - A flame-retardant polyethyleneterephthalate composition - Google Patents

Abstract

PURPOSE: A flame-retardant polyethyleneterephthalate composition is provided to maintain excellent properties and processability compared with existing non-halogen-based flame resistant polyethylene terephthalate products and to replace halogen-based flame resistant polyethylene terephthalate resins. CONSTITUTION: A flame-retardant polyethyleneterephthalate composition includes 40-73 weight% of polyethylene terephthalate resins, 8-12 weight% of phosphate flame retardants, 3-5 weight% of nitrogen-based flame retardant aids, 1-5 weight% of thermoplastic polyester-based elastomers, and 15-45 weight% of glass fibers. A chain extender is included in the amount of 0.1~0.5 weight%. The thermoplastic polyester-based elastomer is prepared by polymerizing aromatic dicarboxylic acids with lower diols. The inherent viscosity of the polyethylene terephthalate resin is 0.6~0.8 dl/g.

Description

A flame-retardant polyethyleneterephthalate composition

The present invention relates to an environmentally friendly flame retardant polyethylene terephthalate resin composition in which no halogen and flame retardant are used. More specifically, the present invention relates to a flame retardant polyethylene terephthalate resin composition having excellent mechanical properties and processability without using halogen and flame retardant.

In general, polyethylene terephthalate resins have a property of burning well, and therefore, it is necessary to impart flame retardance to these resins in order to be used for those requiring flame retardancy such as household appliances. The most commonly used technique for this purpose is to add a flame retardant by adding a halogen flame retardant and inorganic flame retardant auxiliary such as antimony oxide. However, in this case, there is a risk of toxic gas generated by halogen compounds in the case of fire, and it is evaluated to have a very bad effect on the environment.

In order to solve this problem, a method of imparting flame retardancy to polyethylene terephthalate resin using non-halogen flame retardants such as phosphate ester, melamine pyrophosphate, melamine cyanurate, and red has been studied.

However, in the case of using the above method as a flame retardant, it is difficult to color due to the inherent red color, and there is a problem of generating toxic phosphine gas when contacted with moisture at a high temperature during the processing process. In addition, the other flame retardants mentioned above also have problems such as deterioration of physical properties of the resin composition, lowering of workability, and cost increase because it is essential to use a large amount in order to obtain flame retardancy.

An object of the present invention is to provide an environmentally friendly non-halogen flame retardant polyethylene terephthalate resin composition excellent in physical properties and processability in order to solve the problems of the prior art described above.

Still another object of the present invention is to provide a polyethylene terephthalate resin molded article manufactured using the polyethylene terephthalate resin composition.

In order to achieve the above object, the present invention

40 to 73 wt% polyethylene terephthalate resin;

8-12 wt.% Phosphorus-based flame retardant;

3 to 5 weight percent nitrogen based auxiliary flame retardant;

1 to 5% by weight of thermoplastic polyester elastomer; And

15 to 45 wt% glass fiber

It provides a non-halogen flame retardant polyethylene terephthalate resin composition comprising a.

In the following the invention is explained in more detail.

(a) Polyethylene terephthalate  Suzy

Polyethylene terephthalate resin of the present invention may be represented by the following formula (1):

[Formula 1]

Polyethylene terephthalate resin of the present invention can be used that the intrinsic viscosity is 0.6 ~ 0.8dl / g, when the intrinsic viscosity is less than 0.6dl / g there is a problem that the impact strength is lowered, the intrinsic viscosity is 0.8dl / g When it exceeds the viscosity of the resin during the extrusion process is not high impregnation of the glass fiber is not good dispersibility of the glass fiber, there is a problem that the physical properties are lowered.

Polyethylene terephthalate resin may be prepared by polymerizing terephthalic acid of Formula 2 and ethylene glycol of Formula 3:

[Formula 2]

(3)

In the resin composition of the present invention, the content of polyethylene terephthalate resin is preferably 40 to 73% by weight, and when the content is less than 40% by weight, not only the workability may be severely degraded during extrusion / injection, but also the properties may be degraded. If the content is more than% by weight, flame retardancy is difficult.

(b) take over Flame retardant

Phosphorus flame retardant in the resin composition of the present invention may be at least one compound selected from the group consisting of phosphate ester, phosphate, pyrophosphate, phosphonate, metal phosphinate, and the like, in consideration of processing stability and physical properties, etc. Preference is given to using pinates.

In the resin composition of the present invention, the content of the phosphorus-based flame retardant is preferably 8 to 12% by weight. If it is less than 8% by weight, flame retardation is not achieved. When the content is more than 12% by weight, the flame retardancy is excellent, but the workability and physical properties are greatly reduced.

(c) nitrogen-based flame retardant aids

The nitrogen-based flame retardant adjuvant in the resin composition of the present invention may be at least one compound selected from the group consisting of melamine cyanurate, melamine phosphate, melamine polyphosphate, melamine pyrophosphate, and the like, and the use of melamine polyphosphate is most preferred. Do.

In the resin composition of the present invention, the content of the nitrogen-based flame retardant aid is preferably 3 to 5% by weight. If the content is less than 3% by weight, flame retardation is not achieved, and when it is more than 5% by weight, processability and physical properties are greatly reduced.

(d) thermoplastic polyester elastomers

In the resin composition of the present invention, at least one of thermoplastic polyester-based elastomers (TPEE) may be used as the processability improving agent.

Thermoplastic polyester-based elastomers have a structure consisting of a hard segment portion having a main chain structure in the form of an ester forming a structurally highly crystalline domain and a soft segment portion of a polymer polyol composed of a polymer of alcohols as a matrix, and is subjected to repeated loads. Resistance to the resin composition, that is, impact strength, appropriate wear resistance, tensile elongation, tensile strength, and the like is imparted to the resin composition.

The hard segments can be prepared by polymerizing aromatic dicarboxylic acids and lower diols using conventional polymerization methods. Aromatic dicarboxylic acids used in hard segment polymerizations include, but are not limited to, terephthalic acid (TPA), isophthalic acid (IPA), 1,5-naphthalene dicarboxylic acid (1,5-NDCA), 2,6-naphthalene Dicarboxylic acids (2,6-NDCA), aromatic dicarboxylates such as dimethyl isophthalate or mixtures thereof. In particular, it is preferable to use dimethyl isophthalate.

Examples of lower diols used in hard segment polymerizations include, but are not limited to, ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol or 1,4-cyclohexanedimethanol It includes. In particular, it is preferable to use 1,4-butanediol.

As the soft segment, polyalkylene oxide such as, but not limited to, polyoxyethylene glyoxypropylene glycol or polyoxytetramethylene glycol may be used. In particular, it is preferable to use polyoxytetramethylene glycol.

Thermoplastic polyester-based elastomers may be prepared by melt polymerizing the hard segment and the soft segment by conventional polymerization methods. Specifically, oligomerization and polycondensation of the hard and soft segments are performed in two stages. The oligomerization reaction is carried out at 180 to 210 ° C. with a branching agent and a catalyst together with the hard and soft segments for 3 to 4 hours. The oligomer is made to react, and in the step of polycondensation reaction, a branched thermoplastic polyester-based elastomer is formed by reacting at 210 to 250 ° C. for 4 to 5 hours under high vacuum.

The thermoplastic polyester-based elastomer in the composition of the present invention is 1.3-2.2 dl / g when measured under a solvent having an Intrinsic Viscosity of phenol / tetrachloroethane (TCE) = 50/50.

The content of the thermoplastic polyester-based elastomer in the resin composition of the present invention is preferably 1 to 5% by weight. If it is less than 1% by weight, the effect of increasing the strength of the molten strand during extrusion is insignificant. Is improved but there is a problem that the thermal deformation temperature is sharply lowered.

(e) Chain stabilizer

The composition of the present invention may further include a chain stabilizer as a kind of processability improving agent.

The chain stabilizer is an acrylic polymer having an epoxy reactor, for example, glycidyl acrylate, glycidyl methacrylate and the like. It may also be a copolymer of a monomer having an epoxy reactor with other acrylic monomers having no epoxy reactor, such as monomers such as alkyl methacrylates, alkyl acrylates, styrene derivatives, and the like. Specifically, the use of a low molecular weight styrene-acrylate copolymer having 3 to 9 glycidyl reactors is preferable.

The content of the chain extender that can maintain a proper melt tension during extrusion may be included in 0.1 to 0.5% by weight of the total resin composition, and most preferably 0.3% by weight. When the chain extender is added in excess of 0.5% by weight, the strength of the molten strand is excessively increased, so that extrudability is lowered, and at a content of less than 0.1% by weight, the effect of increasing the strength of the molten strand is insignificant.

(f) glass fiber

The resin composition of the present invention includes glass fibers to variously control the mechanical strength and heat resistance. In consideration of the processability and mechanical properties of the polyethylene terephthalate resin, it is preferable to use a glass fiber having a diameter of 8 μm to 18 μm and a length of 2 mm to 7 mm.

Glass fiber is included in 15 to 45% by weight of the total resin composition. If the glass fiber content is less than 15% by weight, the mechanical stiffness and heat resistance is lowered. If the glass fiber content is more than 45% by weight, extrusion is difficult and the moldability during injection is very low.

(g) other additives

Within the range that does not substantially impair the object of the present invention, the resin composition of the present invention, in addition to the above components (a) to (e), a release agent, a heat stabilizer, an antioxidant, a lubricant, a pigment, a light stabilizer, black Additive components commonly used in the art, such as master batches, may be included alone or in combination. For example, inorganic activation such as aluminum hydrate, magnesium hydrate, zinc borate, zinc borate hydrate and magnesium sulfate hydrate used for phosphite and thioester antioxidants and stearates or fatty acid lubricants or polyester flame retardant. Can be used.

The other additive components may be used in 0.05 to 1 parts by weight with respect to 100 parts by weight of the resin composition, it is obvious that the present invention is not necessarily limited thereto.

According to still another object of the present invention, there is provided a polyethylene terephthalate resin molded article produced using the polyethylene terephthalate resin composition of the present invention. In particular, the resin composition of the present invention can be used as a molded article requiring heat resistance and flame retardancy of bobbins, laser printer parts and the like.

The non-halogen flame-retardant polyethylene terephthalate resin composition according to the present invention is free of coloration and is an environmentally friendly resin composition having excellent physical properties, and thus possesses excellent physical properties and processability compared to conventional non-halogen flame-retardant polyethylene terephthalate products. It can be used in place of the flame retardant polyethylene terephthalate resin.

Hereinafter, the present invention will be described in more detail with reference to the following examples.

Hereinafter, the present invention will be described with reference to preferred embodiments, but those skilled in the art can variously change the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. It will be appreciated that modifications and variations can be made.

Example  1 to 3 and Comparative example  1 to 6

To prepare a molding pallet by mixing the raw materials in the composition and content as shown in Table 1, by kneading and extruding with a twin screw melt kneading extruder at a temperature of 240 ~ 270 ℃. Then, after hot air drying at 120 ℃ for 6 hours, the specimen was prepared by injection molding at a temperature of 250 ~ 270 ℃.

(a) Polyethylene terephthalate (TRIPET SB chip, Huvis)

(b) Aluminum phosphinate (Exolit OP1240, client)

(c) Melamine polyphosphate (Melapur 200P, Chivas Specialty)

(d) Thermoplastic polyester elastomer (TRIEL 5720, Samyang)

(e) Chain Extenders (Joncryl ADR-4370S, BASF)

(f) Glass fiber (CS321, KCC)

TABLE 1

division Example (Unit: wt%) Comparative Example (Unit: wt%) One 2 3 One 2 3 4 5 6 (a) 54.6 53.2 54.9 57.2 57.4 48.2 53.2 52.2 53.6 (b) 8.8 10 8.8 7.5 8.8 13 6 15 8.8 (c) 3.8 4 3.8 2.5 3.8 6 8 - 3.8 (d) 2.5 2.5 2.5 2.5 - 2.5 2.5 2.5 6 (e) 0.3 0.3 - One 2 3 4 5 6 (f) 30 30 30 30 30 30 30 30 30

Experimental Example

The physical properties of the specimens of Examples 1 to 3 and Comparative Examples 1 to 6 were measured by the following method, and the results are shown in Table 2:

Tensile strength was measured according to ASTM D638.

The heat deflection temperature was measured by ASTM D648 at a load of 18.6 kgf / cm ² .

Izod impact strength was measured according to ASTM D256.

Flame retardancy was measured by the UL94 V test method. However, in Example 2, flame retardancy was measured using a 0.8 mm thick specimen.

The cutting speed of the molten strand during extrusion increased the pelletizer speed gradually and measured the speed at which the cutting of the strand started. (The minimum speed that can be pelletized at the discharge amount of 15 kg / hr was 250 mm / sec. ).

Table 2

division Example Comparative example One 2 3 One 2 3 4 5 6 Tensile Strength (kg _f / cm ² ) 1250 1200 1270 1300 1070 980 1030 1080 1360 Izod impact strength (kg _f cm / cm) 6 5.5 6.2 6.2 4.5 3.5 4 4.2 9 Heat deflection temperature
(18.6kgf / cm ² ) 218 215 215 221 223 205 197 183 178 Flame retardant
(UL 94, 1.5mm) V-0 V-0
(0.8mm) V-0 HB V-0 V-0 HB HB V-1 Molten strand
Cutting speed (mm / sec) 330 290 290 370 250
Below 250
Below 250 260 420

As can be seen in Table 2, Examples 1 to 3 according to the present invention showed excellent physical properties and processability while showing the flame retardancy of V-0.

In Comparative Example 1 in which the content of the flame retardant is out of the range of the composition of the present invention, the physical properties and processability were good, but the flame retardant grade was HB, and the flame retardancy was insufficient. In the case of Comparative Example 2, the strength of the molten strand during the extrusion process was very weak so that the normal extrusion process was impossible. Comparative Example 3 is a case where the content of the flame retardant exceeds the upper limit in the composition of the present invention, as in Comparative Example 2, the strength of the molten strand during extrusion processing was very weak and extrusion processing was impossible. In Comparative Example 4, the content of the phosphorus-based flame retardant did not fall below the lower limit in the composition of the present invention, and the content of the nitrogen-based flame retardant aid exceeded the upper limit in the composition of the present invention. In Comparative Example 5, only the phosphorus-based flame retardant was included without the nitrogen-based flame retardant adjuvant, and the physical properties and the processability were lowered. In the results of Comparative Examples 4 and 5, even if the total amount of the flame retardant / flame retardant was not appropriate (when not equal to the ratio in the composition of the present invention), not only the physical properties but also the flame retardancy could not be obtained. Comparative Example 6 is a case where the content of the thermoplastic polyester elastomer in the workability enhancer exceeds the upper limit in the composition of the present invention, but the workability and physical properties are very good, but the flame retardancy is reduced to V-1 and the HDT is severely lowered. It was.

In view of the results of the above examples and comparative examples, it can be seen that the content and ratio of the flame retardant / flame retardant aid and the processability enhancer should be formulated as in the composition of the present invention in order to have excellent flame retardancy, physical properties and processability (smooth extrusion). there was.

Claims (9)

40 to 73 wt% polyethylene terephthalate resin; 8-12 wt.% Phosphorus-based flame retardant; 3 to 5 weight percent nitrogen based auxiliary flame retardant; 1 to 5% by weight of thermoplastic polyester elastomer; And Flame retardant polyethylene terephthalate resin composition comprising 15 to 45% by weight of glass fibers. The polyethylene terephthalate resin composition according to claim 1, wherein the resin composition further comprises 0.1 to 0.5% by weight of a chain extender. The polyethylene terephthalate resin composition according to claim 1, wherein the thermoplastic polyester-based elastomer is prepared by polymerizing an aromatic dicarboxylic acid and a lower diol. The polyethylene terephthalate resin composition according to claim 1, wherein the chain extender is an acrylic polymer having an epoxy reactor. The polyethylene terephthalate resin composition according to claim 1, wherein the polyethylene terephthalate resin has an intrinsic viscosity of 0.6 to 0.8 dl / g. The polyethylene terephthalate resin composition according to claim 1, wherein the phosphorus flame retardant is at least one selected from the group consisting of phosphate esters, phosphates, pyrophosphates, phosphonates and metal phosphinates. The polyethylene terephthalate resin composition according to claim 1, wherein the nitrogen-based flame retardant adjuvant is at least one selected from the group consisting of melamine cyanurate, melamine phosphate, melamine polyphosphate and melamine pyrophosphate. The method of claim 1, wherein at least one additive selected from the group consisting of a release agent, a heat stabilizer, an antioxidant, a lubricant, a pigment, a light stabilizer, and a black master batch is added in an amount of about 0.05 to 1 part by weight based on 100 parts by weight of the resin composition. Polyethylene terephthalate resin composition comprising a. The molded article manufactured using the flame-retardant polyethylene terephthalate resin composition of any one of Claims 1-8.