KR20040035980A - Flame Retardant Thermoplastic Resin Composition - Google Patents

Abstract

PURPOSE: Provided is a flame-resistant thermoplastic composition, which has excellent physical properties including flame-resistance, heat resistance and mechanical strength. CONSTITUTION: The flame-resistant thermoplastic composition comprises: 100 parts by weight of a polycarbonate resin; 0.01-1.0 parts by weight of a perfluoroalkane sulfonate salt; and 5-15 parts by eight of a glass fiber. The perfluoroalkane sulfonate salt used as a flame-retardant is selected from the group consisting of a sodium salt or a potassium salt of perfluoromethane sulfonate, perfluoroethane sulfonate, perfluoropropane sulfonate, perfluorobutane sulfonate, perfluoromethylbutane sulfonate, perfluorohexane sulfonate, perfluoroheptane sulfonate and perfluoroocatne sulfonate; tetraethylammonium perfluorobutane sulfonate; tetraethylammonium perfluoromethyl butane sulfonate; and a mixture thereof.

Description

Flame Retardant Thermoplastic Resin Composition

Field of invention

The present invention relates to a polycarbonate-based thermoplastic resin composition excellent in flame retardancy, heat resistance and mechanical strength. More specifically, the present invention relates to a flame retardant thermoplastic resin composition which exhibits excellent flame resistance as well as heat resistance and mechanical strength by adding perfluorinated alkane sulfonate salts and glass fibers to the polycarbonate resin.

Background of the Invention

Polycarbonate resins have been widely used in office automation devices, electrical and electronic products, etc. as engineering plastics due to excellent low temperature impact resistance, self-extinguishing, electrical properties, transparency, dimensional stability and thermal stability compared to other resins.

Since polycarbonate resins are commonly used in molded articles that generate a lot of heat, such as electrical and electronic products or other office equipment, it is essential to maintain flame retardancy and high mechanical strength. In order to impart flame retardancy to such resin compositions, bromine or chlorine-based flame retardants have been added in the past. However, when using such a bromine or chlorine-based flame retardant, the demand for a resin that does not use a bromine or chlorine-based flame retardant is expanding rapidly in recent years due to the problem of human health of the gas generated during combustion.

A technique for imparting flame retardancy without using bromine or chlorine-based flame retardants is to use perfluorinated alkane sulfonate salts in polycarbonate resins.

U.S. Patent No. 3,775,367 discloses the use of perfluorinated alkane sulfonate salts as flame retardants in polycarbonate resins. However, when only perfluorinated alkane sulfonate salts are used in the polycarbonate resin alone, there is a difficulty in the dropping of the spark generated during combustion.

In order to solve this problem, U.S. Patent No. 4,303,575 discloses a technique of adding bromine or chlorine aromatic carboxyl anhydride to the perfluorinated alkane sulfonate salts to prevent dropping during combustion and to improve flame retardancy. However, the method of using such bromine or chlorine-based aromatic carboxylic anhydride has the advantage of improving the flame retardancy, but because it contains bromine or chlorine-based material has a fatal disadvantage of generating toxic gases during combustion.

On the other hand, the present inventors use the perfluoroalkane sulfonate salts in polycarbonate resin as a flame retardant in order to solve the above problems, and by adding a glass fiber thereto, when using the conventional perfluorinated alkane sulfonate salts alone The heat resistance and mechanical strength are improved, and the thermoplastic resin composition excellent in flame retardancy is developed.

An object of the present invention is to provide a thermoplastic resin composition excellent in flame retardancy.

Another object of the present invention is to provide a thermoplastic resin composition having excellent heat resistance.

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

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

The thermoplastic resin composition of the present invention comprises (A) 0.01-1.0 parts by weight of (B) perfluorinated alkane sulfonate salts and 5-15 parts by weight of glass fibers (C) with respect to 100 parts by weight of polycarbonate resin, Detailed description of the components is as follows.

(A) polycarbonate resin

The polycarbonate resin according to the present invention is prepared by reacting diphenols represented by the following formula (1) with phosgene, halogen formate or carbonic acid diester:

[Formula 1]

(Wherein A is a single bond, C _1-5 alkylene, C _1-5 alkylidene, C _5-6 cycloalkylidene, S or SO ₂ ).

Examples of the diphenols represented by the above formula include hydroquinone, resorcinol, 4,4'-dihydroxydiphenyl, 2,2-bis- (4-hydroxyphenyl) -propane, and 2,4-bis- (4- Hydroxyphenyl) -2-methylbutane, 1,1-bis- (4-hydroxyphenyl) -cyclohexane, 2,2-bis- (3-chloro-4-hydroxyphenyl) -propane, 2,2 -Bis- (3,5-dichloro-4-hydroxyphenyl) -propane and the like. Among them, 2,2-bis- (4-hydroxyphenyl) -propane, 2,2-bis- (3,5-dichloro-4-hydroxyphenyl) -propane, 1,1-bis- (4- Bisphenols, such as hydroxyphenyl) -cyclohexane, are preferable, and 2,2-bis- (4-hydroxyphenyl) -propane also called bisphenol-A is especially preferable.

The polycarbonate resin (A) of the present invention has a weight average molecular weight (M _w ) of 10,000 to 200,000, preferably 15,000 to 80,000.

The polycarbonate resin of the present invention may be branched chain, preferably 0.05-2 mol% of tri- or more polyfunctional compounds, such as trivalent or more, based on the total amount of diphenols used for polymerization. It can be prepared by adding a compound having a phenol group.

As the polycarbonate (PC) used in the preparation of the resin composition of the present invention, homopolymers, copolymers, or blends thereof may all be used.

In addition, the polycarbonate resin (A) of the present invention may be used in part or in whole by an aromatic polyester-carbonate resin obtained by polymerizing in the presence of an ester precursor, such as a bifunctional carboxylic acid.

(B) perfluorinated alkane sulfonate salts

In the present invention, the perfluorinated alkane sulfonate salt is used as a flame retardant, and is used in an amount of 0.01 to 1.0 parts by weight based on 100 parts by weight of the polycarbonate resin (A) which is the base resin.

The perfluorinated alkane sulfonate salts of the present invention include perfluoromethane sulfonate, perfluoroethane sulfonate, perfluorinated propane sulfonate, perfluorinated butane sulfonate, perfluorinated methyl butane sulfonate, perfluorinated hexane sulfonate, perfluorinated Sodium or potassium salts of heptane sulfonate, octane perfluoride sulfonate; Tetraethylammonium perfluorinated butane sulfonate, tetraethylammonium perfluorinated methylbutane sulfonate, and the like. These can be used independently from each other, or can use together 2 or more types different from each other.

(C) glass fiber

Glass fiber used in the present invention uses chopped glass fiber having a length of about 3-6 mm. The glass fiber used in the injection molded product is E-glass, and the diameter of the glass fiber generally used is 8-20 μm. The glass fiber of this invention is used in the range of 5-15 weight part with respect to 100 weight part of polycarbonate resin (A) which is a base resin.

Glass fiber sizing compositions are generally treated during or after the fiber manufacture. Lubricating agents, coupling agents, surfactants and the like are used as the glass fiber treatment agent.

Lubricants use suitable additives to form good strands in the manufacture of glass fibers. The coupling agent serves to give good adhesion between the glass fiber and the resin. When various glass fiber treatment agents are developed and properly selected and used according to the type of resin and glass fiber used, the glass fiber reinforcing material is given good physical properties.

In general, the coupling agent treated on the glass fiber is a silane coupling agent and has a structural formula such as YRSiX ₃ .

Y is an organic functional group that can react with the matrix resin. Organic functional groups generally include vinyl groups, epoxy groups, merketane groups, amine groups and acrylic groups.

X is composed of an ethoxy group, a methoxy group, a halogen group and the like, and combines with water in air or an inorganic material to form hydrolyzed silanol. This silanol is combined with an inorganic filler. Therefore, the silane coupling agent has a structure capable of binding by reacting with the dendritic and inorganic filler.

The treatment of the silane coupling agent on the glass fibers is produced in a general manner without particular limitation. The use method of a silane coupling agent includes the method of directly processing into an inorganic filler, and the method of adding to an organic matrix. In order to fully exhibit the performance of the silane coupling agent, the selection and the content of the coupling agent suitable for the inorganic filler and the organic matrix are important.

Glass fibers usable in the present invention are amine-, acryl-, epoxy-based γ-amino propyltriethoxy silane, γ-amino propyltrimethoxy silane, N- ( Beta-aminoethyl) γ-amino propyltriethoxy silane (N- (β-amino ethyl) γ-amino propyltriethoxy silane), γ-methacryloxy propyltriethoxy silane, γ-methoxy Γ-methacryloxy propyltrimethoxy silane, γ-glycidoxy propyltrimethoxy silane, beta (3,4-epoxyethyl) γ-amino propyltrimethoxy silane (β It is treated with a coupling agent such as (3,4-epoxyethyl) γ-amino propyltrimethoxy silane. Among these, glass fibers treated with a gamma -methoxy propyltriethoxy silane coupling agent which is an acrylic coupling agent are preferable.

In addition to the above components, the flame retardant thermoplastic resin composition of the present invention may include general additives such as flame retardant aids, lubricants, mold release agents, nucleating agents, antistatic agents, stabilizers, reinforcing agents, inorganic additive pigments, or dyes according to their respective uses. The added inorganic additive may be used in the range of 0-20 parts by weight, preferably 1-10 parts by weight, based on 100 parts by weight of the base resin component (A).

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 prepared in pellet form.

The flame retardant thermoplastic resin composition of the present invention can be used for molding various products, and is particularly suitable for the manufacture of housings of electrical and electronic products such as computer housings that require flame retardancy and high impact resistance while being injected at high temperatures.

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

The specifications of (A) polycarbonate resin, (B) perfluorinated alkane sulfonate salts, and (C) glass fibers used in the following Examples and Comparative Examples are as follows.

(A) polycarbonate resin

A polycarbonate of bisphenol-A type having a weight average molecular weight (Mw) of 25,000 was used.

(B) perfluorinated alkane sulfonate salts

FR-2025, a commercially available product of 3M potassium perfluorobutane sulfonate, was used.

(C) glass fiber

Owens Corning Co., Ltd., 13 ㎛ in diameter, chop (length 3mm), using a glass fiber treated with a coupling agent such as amino silane and metaoxy silane, and a lubricant and a binding agent.

Example 1-4

Glass fiber (C) was added in each state by adding each component of the composition shown in Table 1, antioxidant, and heat stabilizer, and mixing in a conventional mixer and extrusion-melting using a twin screw extruder having L / D = 34 and Φ = 40 mm. ) Was put into the middle of the extruder to prepare a pellet. After preparing the extrudate in pellet form, a specimen for measuring physical properties and flame retardancy evaluation at an injection temperature of 300 ℃ was prepared using a 10 oz injection machine.

Comparative Example 1-3

Comparative Examples 1 and 2 are free of glass fiber as components, and Comparative Example 3 is free of perfluoroalkane sulfonate salts and glass fiber.

The specimens formed in the Examples and Comparative Examples were measured for 48 hours at 23 ° C. and 50% relative humidity, and then measured for physical properties according to ASTM standards.

(1) Flame retardancy was evaluated using 1.5 mm thick specimens in accordance with UL-94.

(2) The total combustion time is the sum of both primary and secondary combustion times when five specimens were evaluated.

(3) Flexural strength was evaluated according to ASTM D790.

(4) The heat deformation temperature was measured according to ASTM D648.

The composition and physical properties of the resin prepared in Example 1-4 and Comparative Example 1-3 are shown in Table 1 below.

Example Comparative Example One 2 3 4 One 2 3 (A) polycarbonate resin 100 100 100 100 100 100 100 (B) perfluorinated alkanesulfonate salts 0.1 0.1 0.3 1.0 0.1 0.3 - (C) glass fiber 5 10 10 15 - - - UL 94 flame retardant (2.5 mm) V-0 V-0 V-0 V-0 V-1 V-1 V-2 (drip) Total combustion time 40 25 30 35 70 65 - Heat deflection temperature (℃) 135 140 140 141 130 130 130 Flexural Strength (Kgf / ㎠) 900 1,300 1,300 1,600 600 600 600

From the results of Table 1 above, when the glass fiber is added in a suitable amount into the composition using the perfluorinated alkane sulfonate salt as a flame retardant to the polycarbonate base resin, the heat resistance and mechanical properties of the perfluoroalkane sulfonate salt alone are higher than those of the conventional single use of the perfluoroalkane sulfonate salt. It was found that not only the strength was improved but also the synergistic effect of flame retardancy appeared.

The present invention uses a perfluoroalkane sulfonate salt as a flame retardant to a polycarbonate resin, which is a basic resin, and adds glass fiber to it, thereby providing excellent balance of properties such as flame retardancy, heat resistance, and mechanical strength. It has the effect of providing a thermoplastic resin composition useful for producing injection moldings of other office equipment.

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 (4)

(A) 100 parts by weight of polycarbonate resin; (B) 0.01-1.0 parts by weight of perfluorinated alkane sulfonate salts; And (C) 5-15 parts by weight of glass fibers; Flame retardant thermoplastic resin composition comprising a. The perfluoroalkane sulfonate salt (B) is a perfluoromethane sulfonate, a perfluoroethane sulfonate, a perfluorinated propane sulfonate, a perfluorinated butane sulfonate, a perfluorinated methyl butane sulfonate, or a perfluorinated compound. Sodium or potassium salts of hexane sulfonate, perfluorinated heptane sulfonate, octane perfluoride sulfonate; A flame retardant thermoplastic resin composition, characterized in that it is selected from the group consisting of tetraethylammonium perfluorinated butane sulfonate, tetraethylammonium perfluorinated methylbutane sulfonate and mixtures thereof. According to claim 1, wherein the glass fiber is γ-amino propyltriethoxy silane (γ-amino propyltriethoxy silane), γ-amino propyltrimethoxy silane (γ-amino propyltrimethoxy silane), γ-aminopropyl-tris (2 -Methoxy-ethoxy) silane (γ-aminopropyl-tris (2-methoxy-ethoxy) silane), N- (beta-amino ethyl) γ-amino propyl trimethoxy silane (N- (β-amino ethyl) γ -amino propyltrimethoxy silane), N- (beta-aminoethyl) γ-amino propyltriethoxy silane (N- (β-aminoethyl) γ-amino propyltriethoxy silane), and β (3,4-epoxyethyl) γ-amino A flame retardant thermoplastic resin composition characterized in that it is treated with a coupling agent selected from the group consisting of propyl trity methoxy silane. The flame retardant thermoplastic resin composition according to claim 2, wherein the perfluorinated alkane sulfonate salts are potassium perfluorinated butane sulfonate.