KR20190063833A - Glass fiber reinforced polycarbonate resin composition having improved heat stability and flame retardant - Google Patents

Abstract

Disclosed is a polycarbonate resin composition excellent in flame retardancy and thermal stability. The present invention provides the glass fiber reinforced polycarbonate resin composition having excellent flame retardancy, which comprises: 40 to 93 wt% of polycarbonate; 5 to 40 wt% of a glass fiber; 1 to 10 wt% of a phosphorus-based flame retardant containing at least two selected from a group consisting of pyrophosphate, pentaerythritol ester, and diphosphoric acid; and 1 to 10 wt% of a rubber-modified vinyl-based graft copolymer having a core/shell structure.

Description

[0001] The present invention relates to a glass fiber reinforced polycarbonate resin composition having excellent flame retardancy and thermal stability,

The present invention relates to a polycarbonate resin composition, and more particularly, to a polycarbonate resin composition having excellent flame retardancy and thermal stability.

Polycarbonate is widely used as an engineering plastic because it has excellent flame retardancy, heat resistance, impact resistance and electrical insulation.

As a method for imparting improved flame retardancy to a polycarbonate resin, there is a method of adding a flame retardant and a flame retardant adjuvant, and a flame retardant containing a halogen, phosphorus, or the like is added to achieve the flame retardancy. However, when such a flame retardant is added in an excess amount, flame retardancy can be achieved, but there is a problem that the thermal stability is rapidly deteriorated.

In recent years, however, flame retardancy at a thinner thickness has been required due to a reduction in thickness due to slimming of electrical and electronic products. Therefore, phosphorus flame retardants and metal salt flame retardants have been used to improve the flame retardancy of polycarbonate. And it is difficult to find a technique which suggests a resin composition which satisfies flame retardancy and thermal stability at the same time.

Korean Patent No. 10-1772757 describes a phosphorus flame retardant which is used as an antioxidant in consideration of thermal stability and the like, but does not disclose properties relating to flame retardancy.

Korean Patent No. 10-1598354 improves the flame retardancy by adding glass fiber or phosphate ester flame retardant to the polycarbonate resin, but does not disclose the phosphorus flame retardant according to the present invention.

Japanese Patent Registration No. 5021928 discloses that flame retardancy is improved by adding glass fiber or phosphate ester flame retardant to a polycarbonate resin, but does not describe thermal stability.

The present invention aims to provide a polycarbonate resin composition excellent in flame retardancy and thermal stability.

In order to solve the above-mentioned problems, the present invention provides a thermoplastic resin composition comprising 40 to 93% by weight of polycarbonate, 5 to 40% by weight of glass fiber, two or more kinds selected from the group consisting of pyrophosphate, pentaerythritol ester and diphosphoric acid 1 to 10% by weight of a phosphorus-based flame retardant and 1 to 10% by weight of a rubber-modified vinyl-based graft copolymer having a core / shell structure.

Also, the polycarbonate has a melt index (ASTM D1238, 300 캜, 1.2 kg load) of 3 to 28 g / 10 min. The glass fiber reinforced polycarbonate resin composition is excellent in flame retardancy.

The present invention also provides a glass fiber reinforced polycarbonate resin composition excellent in flame retardancy, wherein the glass fiber has a diameter of 5 to 20 탆 and a length of 2 to 5 mm.

Further, the phosphorus flame retardant is characterized by having a residual amount (Residue) of 90% by weight or more when measured by the following method. The glass fiber-reinforced polycarbonate resin composition is excellent in flame retardancy.

[Measurement method of thermal property]

The residue is measured using a thermogravimetric analyzer (TGA) when heat is applied at 800 ° C.

The rubber-modified vinyl-based graft copolymer of the core / shell structure is characterized in that the core is polybutadiene, and the shell is grafted with methyl methacrylate or an achylacrylate polymer. The glass fiber reinforced polycarbonate resin Lt; / RTI >

The present invention also provides a glass fiber reinforced polycarbonate resin composition having excellent flame retardancy, which further comprises 0.01 to 3% by weight of a metal salt-based flame retardant.

The metal salt-based flame retardant may be at least one selected from the group consisting of N- (p -trisulfonyl) -p-toluenesulfonamide, N- (N'-benzylaminocarbonyl) sulfonylamide, N- (phenylcarboxyl) Sulfonic acid, isophthalic acid dimethyl-5-sulfonic acid, 2,6-naphthalene disulfonic acid, benzene sulfonic acid, o-benzene disulfonic acid, 2,4,6- Methyl trichloro-5-sulfoisophthalate, 2,5-dichlorobenzenesulfonic acid, 2,4,5-trichlorobenzenesulfonic acid and perfluoroalkanesulfonic acid metal salt, potassium diphenylsulfonesulfonate, potassium perfluorobutane Wherein the glass fiber reinforced polycarbonate resin composition is at least one selected from the group consisting of sulfonate, sodium trichlorobenzene sulfonate, and polystyrene sulfonic acid metal salt.

The present invention can provide a polycarbonate resin composition excellent in flame retardancy and thermal stability by using a specific phosphorus flame retardant in a specific composition.

Further, it is possible to provide a polycarbonate resin composition having flame retardancy and thermal stability as well as excellent impact strength by further containing a metal salt-based flame retardant having a specific composition.

Hereinafter, preferred embodiments of the present invention will be described in detail. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. Throughout the specification, when an element is referred to as "including " an element, it means that it can include other elements, not excluding other elements, unless specifically stated otherwise.

The present inventors have utilized various additives to improve the flame retardancy and thermal stability of the polycarbonate. However, as a result of intensive study and study on the fact that the effect is concentrated only on flame retardancy, the inventors have found that pyrophosphate, pentaerythritol ester, When a phosphorus flame retardant containing a sporic acid is used in a specific composition, excellent flame retardancy and thermal stability can be achieved at the same time with a small amount of the conventional flame retardant agent. Further, when a metal salt flame retardant is added in a specific composition, excellent impact resistance and heat resistance Stability, and led to the present invention.

Accordingly, the present invention relates to a phosphorus-containing flame retardant comprising 1 to 10% by weight of a phosphorus-containing flame retardant comprising at least one selected from the group consisting of polycarbonate at 40 to 93% by weight, glass fiber at 5 to 40% by weight, pyrophosphate, pentaerythritol ester and diphosphoric acid, And 1 to 10% by weight of a rubber-modified vinyl-based graft copolymer having a core / shell structure. The glass fiber reinforced polycarbonate resin composition is excellent in flame retardancy.

Hereinafter, each component of the polycarbonate resin composition according to one embodiment of the present invention will be described in more detail.

(A) Polycarbonate resin

The polycarbonate (PC) resin used in the present invention is excellent in impact resistance, heat resistance, weather resistance, self-extinguishing ability, flexibility, processability and transparency and excellent in weatherability, Maintain performance to change. In the present invention, the final polycarbonate resin composition is contained in an amount of 40 to 93 wt%, preferably 60 to 86 wt%, more preferably 65 to 86 wt% for balance of physical properties of impact resistance, heat resistance, mechanical strength, 83% by weight.

In addition, the polycarbonate resin according to one embodiment of the present invention may have a weight average molecular weight of 10,000 to 200,000, and preferably 15,000 to 80,000. In addition, a branched chain may be used, and preferably 0.05 to 2 mol% of a trifunctional or more polyfunctional compound, for example, a compound having a trivalent or higher phenol group, is added to the total amount of diphenols used for polymerization A polycarbonate resin can be used.

The polycarbonate resin to be used in the present invention may be prepared according to a commonly used production method. For example, dihydroxyphenol and phosgene are reacted in the presence of a molecular weight regulator and a catalyst. Or by using an ester interchange reaction of a precursor obtained by dihydroxy phenol and diphenyl carbonate.

The polycarbonate resin may be a polymer of bisphenol-A having a melt index (300 캜, 1.2 kgf) of 3 to 28 g / 10 min, preferably 5 to 15 g / 10 min. If the melt index is less than 3 g / 10 min, the processing temperature may become high and molding may be difficult. If the melt index is more than 28 g / 10 min, the strength may be weak.

(B) glass fiber

In the present invention, glass fiber is added to complement the rigidity of a polycarbonate resin composition, which maintains a very strong bonding force between polymers to improve mechanical properties and abrasion resistance, and has durability and flexibility. . The glass fiber may have a diameter of 5 to 20 mu m and a length of 2 to 5 mm, and an effective stiffness is expressed within the above range.

The glass fiber is used in an amount of 5 to 40% by weight, preferably 10 to 25% by weight, in the total resin composition. If the glass fiber content is less than 5% by weight, the required rigidity may not be exhibited. If the glass fiber content is more than 40% by weight, the viscosity of the resin may increase and molding may not be possible.

(C) Phosphorous flame retardant

In the present invention, in order to realize excellent flame retardancy and thermal stability without mixing with other additives or other polymers merely by adding a small amount of a specific phosphorus flame retardant to polycarbonate resin, it is preferable to use pyrophosphate, pentaerythritol ester and diphosphoric acid Phosphorus-based flame retardant containing at least two kinds selected from the group Preferably, the phosphorus flame retardant may comprise the pyrophosphate, pentaerythritol ester and diphosphoric acid.

The phosphorus-based flame retardant used in the present invention was confirmed to have excellent thermal stability at a high temperature of 800 ° C or higher through a thermogravimetric analyzer (TGA). That is, in the case of the conventional phosphorus flame retardant, when heat of 800 ° C or more is applied through a thermogravimetric analyzer (TGA), the phosphorus flame retardant disappears by 80 to 90 wt% or more. However, And showed excellent thermal stability to the extent that the weight loss was not exceeded.

The phosphorus flame retardant is used in an amount of 1 to 10% by weight, preferably 2 to 8% by weight, more preferably 3 to 7% by weight, and most preferably 4 to 6% by weight in the final resin composition have. When the content of the phosphorus-containing flame retardant is less than 1% by weight, the effect of improving the flame retardancy is insignificant. When the content is more than 10% by weight,

(D) a rubber-modified vinyl-based graft copolymer having a core / shell structure

In the present invention, the rubber-modified vinyl-based graft copolymer of the core / shell structure is intended to improve the impact strength of the polycarbonate filled with glass fiber. In particular, for the purpose of maximizing the appearance quality of the resin composition, Polybutadiene is selected as a core component, and methyl methacrylate or alkyl acrylate is selected as a shell component that provides compatibility with a polycarbonate resin.

The content of the rubber component in the rubber-modified vinyl-based graft copolymer of the core / shell structure is preferably 20 to 90% by weight. If the content of the rubber component is less than 20% by weight, it may be difficult to improve the impact strength of the glass fiber-reinforced polycarbonate resin composition. If the content of the rubber component exceeds 90% by weight, the compatibility may be lowered, .

The rubber-modified vinyl-based graft copolymer of the core / shell structure is used in an amount of 1 to 10 wt%, preferably 2 to 8 wt%, in the total resin composition. If the content of the rubber-modified vinyl-based graft copolymer in the core / shell structure is less than 1% by weight, the effect of impact enhancement and surface improvement may be insignificant. If the content is more than 10% by weight, have.

(E) Metal salt flame retardant

Meanwhile, the polycarbonate resin composition according to the present invention may further include a sulfonate metal salt-based flame retardant to improve flame retardancy. In the present invention, the sulfonate-based flame retardant improves the flame retardancy of the polycarbonate resin, and when used as a thin-walled product without deteriorating the impact resistance according to the specific combination of the phosphorus flame retardant, the balance of the flame retardancy, thermal stability, Can be implemented.

Examples of the sulfonate metal salt include N- (p -trisulfonyl) -p-toluenesulfonamide, N- (N'-benzylaminocarbonyl) sulfonylamide, N- (phenylcarboxyl) , Diphenylsulfone-3-sulfonic acid, diphenylsulfone-3,3'-disulfonic acid, isophthalic acid dimethyl-5-sulfonic acid, 2,6-naphthalene disulfonic acid, benzenesulfonic acid, Dichloro-5-sulfoisophthalic acid, 2,5-dichlorobenzenesulfonic acid, 2,4,5-trichlorobenzenesulfonic acid and perfluoroalkanesulfonic acid metal salt, potassium diphenylsulfonesulfonate, potassium perfluoro Sodium trichlorobenzenesulfonate, and polystyrene sulfonic acid metal salt. These may be used singly or in combination of two or more.

The sulfonate-based metal salt flame retardant is used in an amount of 0.01 to 3% by weight, preferably 0.1 to 1% by weight, in the total resin composition. If the content of the sulfonate metal salt flame retardant is less than 0.01% by weight, it may be difficult to exhibit the flame retarding effect, and if it exceeds 3% by weight, the physical properties of the resin may be deteriorated.

The polycarbonate resin composition according to the present invention may further contain an inorganic filler and a functional additive suited to the intended use or effect, in addition to the main components described above. For example, carbon fibers, talc, a flame retardant, a light stabilizer, a lubricant, a colorant, a lubricant, an ultraviolet stabilizer, an antioxidant, a coupling enhancer, a heat stabilizer, a plasticizer and an impact modifier can be further added.

Hereinafter, a specific embodiment of the present invention will be described.

First, the polycarbonate resin (A), the glass fiber (B), the phosphorus flame retardant (P), the rubber-modified vinyl-based graft copolymer (D) of the core / E) The specifications of the metal salt flame retardant are as follows.

(A) Polycarbonate resin

A bisphenol-A type polycarbonate resin (PC-1100S, Lotte Chemical) having a melt index of 10 g / 10 min (300 DEG C / 1.2 kg) was used.

(B) glass fiber

(CS321, manufactured by KCC) having a fiber length of 3 mm and a filament diameter of 13 탆 was used.

(C) Phosphorous flame retardant

(C-1) pyrophosphate, pentaerythritol ester and diphosphoric acid (AODD, Synergy Material Co.) were used. The AODD had a residual of 91.54 wt% when heat of 800 DEG C was applied.

Bisphenol-A bis (diphenylphosphate) (PX-200, Daihachi Co.), which is an aromatic condensed phosphoric acid ester (C-2)

(D) a rubber-modified vinyl-based graft copolymer having a core / shell structure

An impact modifier (DARALOID (TM) EXL-2650J, DOW) having a core / shell structure composed of polybutadiene core and methyl methacrylate as the shell was used.

(E) Metal salt flame retardant

Potassium perfluorobutanesulfonate (RM65, Miteni) was used.

Example 1

(A) 85% by weight of a polycarbonate resin, (B) 10% by weight of glass fiber, (C-1) 3% by weight of phosphorus flame retardant, and (D) 2% by weight of a rubber / modified vinyl graft copolymer having a core / shell structure The thermoplastic resin composition was made into a chip state by using a twin-screw extruder heated to 300 ° C., dried at 100 ° C. for 4 hours by using a hot-air drier, and then the specimen was injection-molded by using a mold for preparing a specimen. On the other hand, it is preferable to minimize the residence time in order to prevent the thermal decomposition of the resin composition during the melt-kneading of the thermoplastic resin composition.

Example 2

A specimen was formed in the same manner as in Example 1, except that 83% by weight of (A) polycarbonate resin and 5% by weight of (C-1) phosphorus flame retardant were mixed in Example 1.

Example 3

A specimen was formed in the same manner as in Example 1, except that 81% by weight of the polycarbonate resin (A) and 7% by weight of the phosphorus flame retardant (C-1) were mixed in Example 1.

Example 4

The same procedure as in Example 1 was carried out except that the content of the polycarbonate resin (A) 82.9% by weight and the content of the (C-1) phosphorus flame retardant were 5% The specimens were formed by the method.

Comparative Example 1

A specimen was formed in the same manner as in Example 1, except that (P-1) phosphorus-based flame retardant was not used and (A) 88 wt% of polycarbonate resin was mixed.

Comparative Example 2

The procedure of Example 1 was repeated except that the phosphorus flame retardant (C-1) was not used, and 87.9% by weight of the polycarbonate resin (A) and 0.1% by weight of the metal salt flame retardant (D) .

Comparative Example 3

The procedure of Example 1 was repeated except for using 81% by weight of the polycarbonate resin (A) and 5% by weight of the phosphorus flame retardant (C-2) without using the phosphorus flame retardant in Example 1 The specimens were molded.

Comparative Example 4

The procedure of Example 1 was repeated except that the phosphorus-based flame retardant (C-1) was not used, and 81% by weight of the polycarbonate resin and 7% by weight of the phosphorus flame retardant (C-2) The specimens were molded.

Component compositions according to Examples and Comparative Examples are summarized in Table 1 below.

Test Example

The properties of each of the samples thus prepared were measured according to the following methods. The results are shown in Table 2 below.

(1) Tensile strength: Measured under the condition of 50 mm / min according to ASTM D638.

(2) Flexural strength and flexural modulus: Measured under the condition of 10 mm / min according to ASTM D790.

(3) IZOD Impact Strength: Notch impact strength of a 1/8 "specimen was measured according to ASTM D256.

(4) Heat distortion temperature (HDT): The heat distortion temperature of the prepared specimen was measured according to ASTM D648.

(5) Flame retardancy: A flame retardancy evaluation according to UL94 specimen of Underwriters Laboratories was performed.

Referring to Table 2, polycarbonate resin (Comparative Example 1) containing glass fiber and rubber-modified vinyl-based graft copolymer and Comparative Example 2 (Comparative Examples 2 to 4) were used as flame retardant or metal salt flame retardant alone (HDT) and flame retardancy are improved, but the thermal stability (HDT) and the impact strength are sharply lowered.

On the other hand, when the phosphorus-based flame retardant (C-1) according to the present invention was added to polycarbonate resin containing glass fiber and rubber-modified vinyl-based graft copolymer (Examples 1 to 3), phosphorus flame retardant or metal salt- (Comparative Examples 2, 3 and 4), the flame retardancy and the thermal stability (HDT) were improved.

(Examples 2 and 3) containing the phosphorus-based flame retardant (C-1) according to the present invention exhibited excellent flame retardancy with a smaller content (5% by weight of Example 2) And can increase thermal stability and impact resistance.

The flame retardancy, thermal stability and impact resistance were superior to those of the metal flame retardant (Example 4) alone (Comparative Example 2), and the phosphorus flame retardant (C-1) according to the present invention was used alone (Example 2), it is understood that the thermal stability and the impact resistance are more improved while maintaining the flame retardancy equivalent to the case (Example 2).

The preferred embodiments of the present invention have been described in detail above. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Accordingly, the scope of the present invention is defined by the appended claims rather than the foregoing detailed description, and all changes or modifications derived from the meaning, range, and equivalence of the claims are included in the scope of the present invention Should be interpreted.

Claims (7)

1 to 10% by weight of a phosphorus-based flame retardant containing at least two selected from the group consisting of polycarbonate 40 to 93% by weight, glass fiber 5 to 40% by weight, pyrophosphate, pentaerythritol ester and diphosphoric acid, / Shell structure, and 1 to 10% by weight of a rubber-modified vinyl-based graft copolymer. The glass fiber-reinforced polycarbonate resin composition according to claim 1, The method according to claim 1,
Wherein the polycarbonate has a melt index (ASTM D1238, 300 캜, 1.2 kg load) of 3 to 28 g / 10 min. The glass fiber reinforced polycarbonate resin composition of the present invention is excellent in flame retardancy. The method according to claim 1,
The glass fiber reinforced polycarbonate resin composition of claim 1, wherein the glass fiber has a diameter of 5 to 20 탆 and a length of 2 to 5 mm. The method according to claim 1,
Wherein the phosphorus-based flame retardant has a residual value of 90% by weight or more when measured by the following method.
[Measurement method of thermal property]
The residue is measured using a thermogravimetric analyzer (TGA) when heat is applied at 800 ° C. The method according to claim 1,
The rubber-modified vinyl-based graft copolymer of the core / shell structure is characterized in that the core is polybutadiene and the shell is grafted with methyl methacrylate or an achylacrylate polymer. The glass fiber reinforced polycarbonate resin composition . The method according to claim 1,
Wherein the composition further comprises 0.01 to 3% by weight of a metal salt-based flame retardant. The method according to claim 6,
The metal salt flame retardant may be at least one selected from the group consisting of N- (p -trisulfonyl) -p-toluenesulfonamide, N- (N'-benzylaminocarbonyl) sulfonylamide, N- (phenylcarboxyl) Sulfone-3-sulfonic acid, diphenylsulfone-3,3'-disulfonic acid, isophthalic acid dimethyl-5-sulfonic acid, 2,6-naphthalene disulfonic acid, benzenesulfonic acid, Metal salts of 2,5-dichlorobenzenesulfonic acid, 2,4,5-trichlorobenzenesulfonic acid and perfluoroalkanesulfonic acid, potassium diphenylsulfonesulfonate, potassium perfluorobutanesulfonate Wherein the flame retardant is at least one selected from the group consisting of polytetrafluoroethylene, naphthalene, sodium trichlorobenzenesulfonate, and polystyrene sulfonic acid metal salts.