Polycarbonate-based resin composition and molded article thereof

Abstract

The present invention relates to a polycarbonate-based resin composition and a molded article thereof, and more particularly, to a polycarbonate-based resin composition exhibiting low deformation characteristic, excellent impact strength, excellent appearance surface characteristic, and excellent flame retardancy, and a molded article formed therefrom.

Claims

1. A polycarbonate-based resin composition comprising: a polycarbonate resin including an aromatic polycarbonate-based first repeating unit, a copolycarbonate resin including an aromatic polycarbonate-based first repeating unit, and an aromatic polycarbonate-based second repeating unit having one or more siloxane bonds, a glass fiber, an impact-reinforcing agent including a rubber-modified vinyl-based graft copolymer, and a phosphorus-based flame retardant; wherein the first repeating unit each independently includes a repeating unit represented by Chemical Formula 1 below, the second repeating unit includes at least one repeating unit selected from the group consisting of Chemical Formula 3 below, and; the glass fiber has a rectangular, circular or elliptical cross section in a direction perpendicular to a longitudinal direction, and has an aspect ratio according to Equation 1 below of 100 to 500, a length (L) of 2 to 7 mm, and D of 5 to 20 m:
Aspect ratio ()=L/D[Equation 1] in Equation 1, L is a length of the glass fiber, D is a length of the longest side of the rectangular cross section, a length of a diameter of the circular cross section, or a length of the longest diameter of the elliptical cross section, ##STR00023## in Chemical Formula 1, R.sup.1 to R.sup.4 are each independently hydrogen, C.sub.1-10 alkyl, C.sub.1-10 alkoxy, or halogen, and Z is C.sub.1-10 alkylene unsubstituted or substituted with phenyl, C.sub.3-15 cycloalkylene unsubstituted or substituted with C.sub.1-10 alkyl, O, S, SO, SO.sub.2, or CO; ##STR00024## in Chemical Formula 3, X.sup.2 is each independently C.sub.1-10 alkylene, Y.sup.1 is each independently hydrogen, C.sub.1-6 alkyl, halogen, hydroxy, C.sub.1-6 alkoxy or C.sub.6-20 aryl, R.sup.6 is each independently hydrogen; C.sub.1-15 alkyl unsubstituted or substituted with oxiranyl, oxiranyl-substituted C.sub.1-10 alkoxy, or C.sub.6-20 aryl; halogen; C.sub.1-10 alkoxy; allyl; C.sub.1-10 haloalkyl; or C.sub.6-20 aryl, and n2 is an integer of 10 to 200.

2. The polycarbonate-based resin composition of claim 1, wherein: the polycarbonate resin has a melt index (MI) of 5 g/10 min to 25 g/10 min at a temperature of 300 C. and a load of 1.2 kg.

3. The polycarbonate-based resin composition of claim 1, wherein: the second repeating unit further includes at least one repeating unit selected from the group consisting of Chemical Formula 2 below: ##STR00025## in Chemical Formula 2, X.sup.1 is each independently C.sub.1-10 alkylene, R.sup.5 is each independently hydrogen; C.sub.1-15 alkyl unsubstituted or substituted with oxiranyl, oxiranyl-substituted C.sub.1-10 alkoxy, or C.sub.6-20 aryl; halogen; C.sub.1-10 alkoxy; allyl; C.sub.1-10 haloalkyl; or C.sub.6-20 aryl, and n1 is an integer of 10 to 200.

4. The polycarbonate-based resin composition of claim 1, wherein: the repeating unit represented by Chemical Formula 1 is represented by Chemical Formula 1-1 below: ##STR00026##

5. The polycarbonate-based resin composition of claim 3, wherein: the repeating unit represented by Chemical Formula 2 is represented by Chemical Formula 2-1 below: ##STR00027## in Chemical Formula 2-1, R.sup.5 and n1 are each the same as defined in Chemical Formula 2 above.

6. The polycarbonate-based resin composition of claim 1, wherein: the repeating unit represented by Chemical Formula 3 is represented by Chemical Formula 3-1 below: ##STR00028## in Chemical Formula 3-1, R.sup.6 and n2 are each the same as defined in Chemical Formula 3 above.

7. The polycarbonate-based resin composition of claim 1, wherein: the copolycarbonate resin includes 90 to 99.999 wt % of the first repeating unit and 0.001 to 10 wt % of the second repeating unit.

8. The polycarbonate-based resin composition of claim 1, wherein: the polycarbonate resin and the copolycarbonate resin each have a weight average molecular weight of 1,000 to 100,000 g/mol.

9. The polycarbonate-based resin composition of claim 1, wherein: the glass fiber is a glass fiber surface-treated with an epoxy silane-based compound or an olefin silane-based compound, or a surface-untreated glass fiber.

10. The polycarbonate-based resin composition of claim 1, wherein: the rubber-modified vinyl-based graft copolymer is a graft copolymer having a core-shell structure in which a vinyl-based unsaturated monomer is grafted to a core structure to form a shell, the core structure including at least one rubber selected from the group consisting of diene-based rubber, acrylate-based rubber and silicone-based rubber.

11. The polycarbonate-based resin composition of claim 1, wherein: the phosphorus-based flame retardant includes a condensed phosphoric acid ester represented by Chemical Formula 5 below: ##STR00029## in Chemical Formula 5, Ar.sup.1, Ar.sup.2, Ar.sup.3 and Ar.sup.4 are each independently halogen-free aromatic group, Q is ##STR00030## R.sup.7 to R.sup.14 are each independently a hydrogen atom or a C.sub.1-5 alkyl group; G is a direct binding, O, S, SO.sub.2, C(CH.sub.3).sub.2, CH.sub.2, and CHPh, and Ph is phenyl group, n is an integer of 1 or more, and k and m are each an integer of 0 to 2, and (k+m) is an integer of 0 to 2.

12. The polycarbonate-based resin composition of claim 1, wherein the polycarbonate-based resin composition includes: 20 to 70 wt % of the polycarbonate resin, 10 to 70 wt % of the copolycarbonate resin, 1 to 20 wt % of the glass fiber, 1 to 10 wt % of the impact-reinforcing agent, and 2 to 15 wt % of the phosphorus-based flame retardant.

13. The polycarbonate-based resin composition of claim 1, wherein: the polycarbonate-based resin composition further includes a drip inhibitor of a fluoropolymer.

14. A molded article comprising the polycarbonate-based resin composition of claim 1.

Description

EXAMPLES

(1) Hereinafter, preferable Examples of the present invention will be provided for better understanding of the present invention. However, the following Examples are provided only for illustration of the present invention, and should not be construed as limiting the present invention by the examples.

Preparation Example 1

(2) Preparation of polyorganosiloxane (AP-PDMS, n1=34)

(3) ##STR00021##

(4) After 47.6 g (160 mmol) of octamethylcyclotetrasiloxane and 2.4 g (17.8 mmol) of tetramethyldisiloxane were mixed with each other, the mixture was placed in a 3 L flask with 1 part by weight of acid clay (DC-A3) based on 100 parts by weight of octamethylcyclotetrasiloxane, and reacted at 60 C. for 4 hours. After the reaction was terminated, the reaction product was diluted with ethylacetate and quickly filtered using a celite. The repeating unit (n1) of the unmodified polyorganosiloxane obtained as described above was 34 when confirmed through .sup.1H NMR.

(5) 4.81 g (35.9 mmol) of 2-allylphenol and 0.01 g (50 ppm) of Karstedt's platinum catalyst were added to the obtained terminal-unmodified polyorganosiloxane and reacted at 90 C. for 3 hours. After the reaction was terminated, the unreacted polyorganosiloxane was removed by evaporation under condition of 120 C. and 1 torr. The terminal-modified polyorganosiloxane obtained as described above was designated as AP-PDMS (n1=34). AP-PDMS was pale yellow oil, the repeating unit (n1) was 34 when confirmed through .sup.1H NMR using Varian 500 MHz, and further purification was not required.

Preparation Example 2

(6) Preparation of polyorganosiloxane (MBHB-PDMS, n2=58)

(7) ##STR00022##

(8) After 47.60 g (160 mmol) of octamethylcyclotetrasiloxane and 1.5 g (11 mmol) of tetramethyldisiloxane were mixed with each other, the mixture was placed in a 3 L flask with 1 part by weight of acid clay (DC-A3) based on 100 parts by weight of octamethylcyclotetrasiloxane, and reacted at 60 C. for 4 hours. After the reaction was terminated, the reaction product was diluted with ethylacetate and quickly filtered using a celite. The repeating unit (n2) of the terminal-unmodified polyorganosiloxane obtained as described above was 58 when confirmed through .sup.1H NMR.

(9) 6.13 g (29.7 mmol) of 3-methylbut-3-enyl 4-hydroxybenzoate and 0.01 g (50 ppm) of Karstedt's platinum catalyst were added to the obtained terminal-unmodified polyorganosiloxane and reacted at 90 C. for 3 hours. After the reaction was terminated, the unreacted polyorganosiloxane was removed by evaporation under condition of 120 C. and 1 torr. The terminal-modified polyorganosiloxane obtained as described above was designated as MBHB-PDMS (n2=58). MBHB-PDMS was pale yellow oil, the repeating unit (n2) was 58 when confirmed through .sup.1H NMR using Varian 500 MHz, and further purification was not required.

Preparation Example 3

(10) Preparation of copolycarbonate resin:1784 g of water, 385 g of NaOH and 232 g of bisphenol A (BPA) were added to a polymerization reactor, and dissolved with mixing under N.sub.2 atmosphere. To the above-prepared mixture, 4.3 g of para-tert butylphenol (PTBP) and a mixed solution of 4.72 g of AP-PDMS (n1=34) prepared by Preparation Example 1 and 0.52 g of MBHB-PDMS (n2=58) prepared by Preparation Example 2 dissolved in methylene chloride (MC) were added. Subsequently, 128 g of triphosgene (TPG) was dissolved in MC and the dissolved TPG solution was added to the mixture and reacted for 1 hour while maintaining pH at 11 or more. After 10 minutes, 46 g of triethylamine (TEA) was added thereto to perform a coupling reaction. After a total reaction time of 1 hour and 20 minutes, TEA was removed by lowering the pH to 4, and then the produced polymer was washed three times with distilled water so that pH was adjusted to neutral pH of 6 to 7. The obtained polymer was re-precipitated in a mixed solution of methanol and hexane, and dried at 120 C. to finally obtain a copolycarbonate resin (Mw=30,500).

Example and Comparative Example

(11) Respective components were added according to composition shown in Table 1 below, followed by melting and kneading-extrusion, thereby preparing pellets. The prepared pellets were dried at 70 C. for 6 hours, followed by injection-molding, to manufacture samples for evaluating physical properties.

(12) The components used in respective Examples and Comparative Examples are as follows.

(13) (A) Bisphenol A Polycarbonate Resin (PC)

(14) The polycarbonate resin is a polymer of bisphenol A, and a melt index (MI) thereof was measured as a weight (g) measured for 10 minutes at a temperature of 300 C. and a load of 1.2 kg according to ASTM D1238. As a result of the measurement, an aromatic polycarbonate resin having a melt index of 10 g/10 min (PC1300-10 manufactured by LG Chem.) was used.

(15) (B) Copolycarbonate Resin (PC 8000-05 manufactured by LG Chem.) according to Preparation Example 3

(16) (C) Glass Fiber

(17) A chopped strand G/F 415A (for high impact polycarbonate and polyethylene) having a diameter (D) of 14 m, a length (L) of 5 mm and an aspect ratio () calculated by Equation 1 of about 357 and manufactured by Owens Corning was used.

(18) (D) Metablen S-2100 Using a Silicone-Acrylate Rubber Manufactured by MRC of Japan was Used as the Impact-Reinforcing Agent of the Rubber-Modified Vinyl-Based Graft Aopolymer.

(19) (E) Phosphorus-Based Flame Retardant

(20) FP-600, a liquid flame retardant which is bisphenol-A bis(diphenylphosphate), was used.

(21) (F) Drip Inhibitor

(22) Polytetrafluoroethylene (PTFE) was used (Xflon-G manufactured by POCERA Co.).

(23) TABLE-US-00001 TABLE 1 Exam- Exam- Exam- Comparative Comparative Example 1 ple 2 ple 3 ple 4 Example 1 Example 2 (wt %) (wt %) (wt %) (wt %) (wt %) (wt %) A 66.3 36.3 62.3 67.3 86.3 83.3 B 20 50 20 20 0 0 C 5 5 5 5 5 5 D 2 2 2 1 2 5 E 6 6 10 6 6 6 F 0.7 0.7 0.7 0.7 0.7 0.7

Experimental Example

(24) Physical properties of each sample formed from each composition of Examples and Comparative Examples were measured by the following methods, and results thereof were shown in Table 2 below.

(25) (1) Melt index (MI): calculated as a weight (g) measured at a temperature of 300 C. and a load of 1.2 kg for 10 minutes according to ASTM D1238.

(26) (2) Impact strength (IZOD): measured at a temperature of 23 C. with inch (Notched Izod, J/m) according to ASTM D256.

(27) (3) Flame Retardant Rating: measured according to UL 94 V Test (vertical burning test, 1.6 mm) standard.

(28) TABLE-US-00002 TABLE 2 Comparative Comparative Example 1 Example 2 Example 3 Example 4 Example 1 Example 2 Melt Index 10 7 13 11 12 12 (g/10 min) Impact 25 35 20 21 18 26 Strength (kgcm/cm) Flame V-1 V-1 V-0 V-1 V-1 V-2 Retardant Rating

(29) Referring to Table 2 above, it was confirmed that Examples exhibited excellent flame retardancy or impact strength as compared to Comparative Examples, together with the excellent melt index.