Polycarbonate composition and article comprising the same

Abstract

Disclosed is a polycarbonate composition including (a) a branched polycarbonate comprising a repeating unit represented by Chemical Formula 1 and a trivalent or tetravalent branched repeating unit connecting the plurality of repeating units represented by Chemical Formula 1 to each other; and (b) a copolycarbonate comprising an aromatic polycarbonate-based first repeating unit, and aromatic polycarbonate-based second repeating units having siloxane bonds which include a repeating unit represented by Chemical Formula 4 and a repeating unit represented by Chemical Formula 5: ##STR00001##
The polycarbonate composition improves flame retardancy and chemical resistance while maintaining high impact strength and melt index.

Claims

1. A polycarbonate composition comprising: (a) a branched polycarbonate comprising a repeating unit represented by Chemical Formula 1 and a trivalent or tetravalent branched repeating unit connecting the plurality of repeating units represented by Chemical Formula 1 to each other; and (b) a copolycarbonate comprising an aromatic polycarbonate-based first repeating unit, and one or more aromatic polycarbonate-based second repeating units having siloxane bonds, wherein the second repeating unit comprises a repeating unit represented by Chemical Formula 4 and a repeating unit represented by Chemical Formula 5: ##STR00025## in the Chemical Formula 1, R.sub.1, R.sub.2, R.sub.3 and R.sub.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, ##STR00026## in Chemical Formula 4, X.sub.1 is each independently C.sub.1-10 alkylene, R.sub.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 n is an integer of 10 to 200, ##STR00027## in Chemical Formula 5, X.sub.2 is each independently C.sub.1-10 alkylene, Y.sub.1 is each independently hydrogen, C.sub.1-6 alkyl, halogen, hydroxy, C.sub.1-6 alkoxy, or C.sub.6-20 aryl, R.sub.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 m is an integer of 10 to 200, and wherein a weight ratio of the branched polycarbonate and the copolycarbonate is 20:80 to 40:60.

2. The polycarbonate composition of claim 1, wherein: the repeating unit represented by Chemical Formula 1 is derived from any one or more aromatic diol compounds selected from the group consisting of bis(4-hydroxyphenyl)methane, bis(4-hydroxyphenyl)ether, bis(4-hydroxyphenyl)sulfone, bis(4-hydroxyphenyl)sulfoxide, bis(4-hydroxyphenyl)sulfide, bis(4-hydroxyphenyl)ketone, 1,1-bis(4-hydroxyphenyl)ethane, bisphenol A, 2,2-bis(4-hydroxyphenyl)butane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 2,2-bis(4-hydroxy-3,5-dibromophenyl)propane, 2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane, 2,2-bis(4-hydroxy-3-bromophenyl)propane, 2,2-bis(4-hydroxy-3-chlorophenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, and bis(4-hydroxyphenyl)diphenylmethane.

3. The polycarbonate composition of claim 1, wherein: the repeating unit represented by Chemical Formula 1 is represented by Chemical Formula 1-1 below: ##STR00028##

4. The polycarbonate composition of claim 1, wherein: the trivalent or tetravalent branched repeating unit is a repeating unit represented by Chemical Formula 2 below: ##STR00029## in the Chemical Formula 2, R.sub.5 is hydrogen, C.sub.1-10 alkyl, or ##STR00030## R.sub.6, R.sub.7, R.sub.8 and R.sub.9 are each independently hydrogen, C.sub.1-10 alkyl, halogen, C.sub.1-10 alkoxy, allyl, C.sub.1-10 haloalkyl, or C.sub.6-20 aryl, and n1, n2, n3 and n4 are each independently an integer of 1 to 4.

5. The polycarbonate composition of claim 4, wherein: the repeating unit represented by Chemical Formula 2 is represented by Chemical Formula 2-2 below or Chemical Formula 2-3 below: ##STR00031##

6. The polycarbonate composition of claim 4, wherein: a weight ratio of the repeating unit represented by Chemical Formula 1 and the repeating unit represented by Chemical Formula 2 is 1:0.001 to 1:0.1.

7. The polycarbonate composition of claim 1, wherein: a weight average molecular weight of the polycarbonate is 1,000 to 100,000.

8. The polycarbonate composition of claim 1, wherein: a polysiloxane structure is not introduced in a main chain of the branched polycarbonate.

9. The polycarbonate composition of claim 1, wherein: the first repeating unit is represented by Chemical Formula 3 below: ##STR00032## in the Chemical Formula 3, R.sub.1, R.sub.2, R.sub.3 and R.sub.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.

10. The polycarbonate composition of claim 9, wherein: the Chemical Formula 3 is represented by Chemical Formula 3-1 below: ##STR00033##

11. The polycarbonate composition of claim 1, wherein: a weight ratio of the repeating unit represented by Chemical Formula 4 and the repeating unit represented by Chemical Formula 5 is 1:99 to 99:1.

12. The polycarbonate composition of claim 1, wherein: the repeating unit represented by Chemical Formula 4 is represented by Chemical Formula 4-2 below: ##STR00034##

13. The polycarbonate composition of claim 1, wherein: the repeating unit represented by Chemical Formula 5 is represented by Chemical Formula 5-2 below: ##STR00035##

14. The polycarbonate composition of claim 1, wherein: a weight average molecular weight of the copolycarbonate is 1,000 to 100,000.

15. The polycarbonate composition of claim 1, further comprising: an unbranched polycarbonate in which a polysiloxane structure is not introduced in a main chain of the polycarbonate, and the branched repeating unit is not included.

16. The polycarbonate composition of claim 15, wherein: the unbranched polycarbonate comprises a repeating unit represented by Chemical Formula 6 below: ##STR00036## in the Chemical Formula 6, R.sub.1, R.sub.2, R.sub.3 and R.sub.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.

Description

DETAILED DESCRIPTION OF THE EMBODIMENTS

(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: Preparation of Polyorganosliloxane (AP-30)

(2) ##STR00023##

(3) After 42.5 g (142.8 mmol) of octamethylcyclotetrasiloxane and 2.26 g (16.8 mmol) of tetramethyldisiloxane were mixed, 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 (n) of the unmodified polyorganosiloxane obtained as described above was 30 when confirmed through .sup.1H NMR.

(4) 9.57 g (71.3 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-30. AP-30 was pale yellow oil, the repeating unit (n) was 30 when confirmed through .sup.1H NMR using Varian 500 MHz, and further purification was not required.

Preparation Example 2: Preparation of Polyorganosiloxane (MB-60)

(5) ##STR00024##

(6) After 47.60 g (160 mmol) of octamethylcyclotetrasiloxane and 1.5 g (11 mmol) of tetramethyldisiloxane were mixed, 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 (m) of the terminal-unmodified polyorganosiloxane obtained as described above was 60 when confirmed through .sup.1H NMR.

(7) 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 MB-60. MB-60 was pale yellow oil, the repeating unit (m) was 60 when confirmed through .sup.1H NMR using Varian 500 MHz, and further purification was not required.

Preparation Example 3: Preparation of Copolycarbonate (PPC)

(8) 978.4 g of bisphenol A (BPA), 1,620 g of 32% NaOH aqueous solution, and 7,500 g of distilled water were placed in a 20 L glass reactor, and it was confirmed that the BPA was completely dissolved in a nitrogen atmosphere. Then, 3,670 g of methylene chloride, 18.3 g of p-tert-butylphenol (PTBP), 49.68 g of the previously prepared polyorganosiloxane (AP-30), and 5.52 g of the polyorganosiloxane (MB-60) of Preparation Example 2 were added thereto and mixed. To the mixture, 3,850 g of methylene chloride in which 542.5 g of triphosgene was dissolved, was added dropwise for one hour. Here, pH of the NaOH aqueous solution was maintained at pH 12. After the addition was terminated, the mixture was aged for 15 minutes, and 195.7 g of triethylamine was dissolved in methylene chloride (MC) and then added to the mixture. After 10 minutes, pH of the mixture was adjusted to pH 3 with 1N hydrochloric acid aqueous solution. The obtained product was washed three times with distilled water to separate the methylenechloride phase, and precipitated in methanol to obtain a copolycarbonate resin in a powder form. The obtained resin was designated as PPC.

Preparation Example 4: Preparation of Branched Polycarbonate (B-PC)

(9) 978.4 g of bisphenol A (BPA), 3.2 g of THPE (1,1,1-tris(4-hydroxyphenyl)ethane), 1,620 g of 32% NaOH aqueous solution, and 7,500 g of distilled water were placed in a 20 L glass reactor, and it was confirmed that the BPA was completely dissolved in a nitrogen atmosphere. Then, 3,670 g of methylene chloride, and 21.0 g of p-tert-butylphenol (PTBP) were added thereto and mixed. To the mixture, 3,850 g of methylene chloride in which 542.5 g of triphosgene was dissolved, was added dropwise for one hour. Here, pH of the NaOH aqueous solution was maintained at pH 12. After the addition was terminated, the mixture was aged for 15 minutes, and 195.7 g of triethylamine was dissolved in methylene chloride and then added to the mixture. After 10 minutes, pH of the mixture was adjusted to pH 3 with 1N hydrochloric acid aqueous solution. The obtained product was washed three times with distilled water to separate the methylenechloride phase, and precipitated in methanol to obtain a polycarbonate resin in a powder form. The obtained resin was designated as B-PC, and had a weight average molecular weight of 28,100, the weight average molecular weight being measured by GPC with PC Standard using Agilent 1200 series.

Example 1

(10) A polycarbonate composition was prepared by mixing 80 parts by weight of PPC prepared by Preparation Example 3 with 20 parts by weight of B-PC prepared by Preparation Example 4.

Example 2

(11) A polycarbonate composition was prepared by mixing 70 parts by weight of PPC prepared by Preparation Example 3 with 30 parts by weight of B-PC prepared by Preparation Example 4.

Example 3

(12) A polycarbonate composition was prepared by mixing 60 parts by weight of PPC prepared by Preparation Example 3 with 40 parts by weight of B-PC prepared by Preparation Example 4.

Comparative Example 1

(13) The PPC prepared by Preparation Example 3 was determined as Comparative Example 1.

Comparative Example 2

(14) A polycarbonate resin was obtained by the same method as Preparation Example 3, except that the polyorganosiloxane (AP-30) and the polyorganosiloxane (MB-60) were not used. The obtained polycarbonate resin was determined as Comparative Example 2.

Comparative Example 3

(15) A polycarbonate composition was prepared by mixing 70 parts by weight of PPC prepared by Preparation Example 3 with 30 parts by weight of polycarbonate prepared by Comparative Example 2.

Comparative Example 4

(16) A polycarbonate composition was prepared by mixing 25 parts by weight of B-PC prepared by Preparation Example 4 with 75 parts by weight of polycarbonate prepared by Comparative Example 2.

Experimental Example

(17) 0.050 parts by weight of tris(2,4-di-tert-butylphenyl)phosphite, 0.010 parts by weight of octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, and 0.030 parts by weight of pentaerythritol tetrastearate were added to 1 part weight of each resin of examples and comparative examples, and then each mixture was pelletized using a 30 mm twin-screw extruder provided with a vent, and injection-molded at a cylinder temperature of 300 C. and a mold temperature of 80 C. using an N-20C injection molding machine of JSW, LTD., to manufacture each specimen.

(18) Characteristics of each specimen were measured as follows:

(19) 1) Weight average molecular weight (g/mol): measured by GPC with PC Standard using Agilent 1200 series.

(20) 2) Impact strength at room temperature: measured at 23 C. in accordance with ASTM D256 ( inch, Notched Izod).

(21) 3) Impact strength at low temperature: measured at 30 C. in accordance with ASTM D256 ( inch, Notched Izod).

(22) 4) Melt Index (MI): measured in accordance with ASTM D1238 (under condition of 300 C., 1.2 kg).

(23) 5) Flame retardancy: evaluated in accordance with UL 94V. Specifically, five specimens having a thickness of 3.0 mm required for a flame retardancy test were prepared, and evaluated as follows.

(24) First, a flame having a height of 20 mm was applied to each specimen for 10 seconds, and then a combustion time (t1) of the specimen was measured, and a combustion aspect was recorded. Then, after the primary flame-contact, and the combustion was terminated, a flame was in contact with each specimen for another 10 seconds (secondary flame-contact). Next, a combustion time (t2) and a glowing time (t3) of the specimen were measured, and a combustion aspect was recorded. The above-described flame retardancy test was equally applied to five specimens, and the specimens were evaluated as shown in Table 1 below.

(25) TABLE-US-00001 TABLE 1 Flame retardancy rating V-0 V-1 V-2 Each combustion time Not more than Not more than Not more than (t1 or t2 of each 10 sec 30 sec 30 sec specimen) Total combustion time Not more than Not more than Not more than of five specimens (sum 50 sec 250 sec 250 sec of t1 and t2 of five specimens) Combustion time and Not more than Not more than Not more than glowing time 30 sec 60 sec 60 sec after secondary flame-contact (sum of t2 and t3 of each specimen) Whether particle None None Yes causing flame is dropped

(26) 6) Chemical Resistance: Specimens (thickness: 3.2 mm) were manufactured to measure tensile strength in accordance with ASTM D638, and chemical resistance thereof was measured on the basis of JIG Strain R1.0 in accordance with ASTM D543 (PRACTICE B). Specifically, a cotton cloth (2 cm2 cm) was placed on the center of each specimen at room temperature (23 C.), and then time required for causing destruction of each specimen from the moment 2 mL of a solvent (Nivea Aqua Protect Sun SpraySPF30, Beiersdorf Inc.) was dropped on the cloth, was measured. The measured time was evaluated by the following criteria:

(27) : 1 hour to 24 hours

(28) X: within 1 minute

(29) The results were shown in Table 2 below.

(30) TABLE-US-00002 TABLE 2 Unit Ex. 1 Ex. 2 Ex. 3 C. EX. 1 C. EX. 2 C. EX. 3 C. EX. 4 Mw g/mol 30,100 29,300 29,800 28,900 28,100 27,500 29,800 Impact strength J/m 878 840 811 848 820 815 875 at room temperature Impact strength J/m 760 728 699 681 190 350 185 at low temperature Melt index g/10 min 10 9 8 10 12 10 11 Flame V-1 V-1 V-0 V-1 V-2 V-1 V-2 retardancy Chemical X X X X resistance

(31) As shown in Table 2 above, it could be confirmed that examples had an improved chemical resistance while maintaining the impact strength at the same level as compared to comparative examples. Therefore, it could be confirmed that the polycarbonate composition according to the present invention comprises the copolycarbonate comprising the specific siloxane structure and the polycarbonate comprising the branched repeating unit to improve the chemical resistance while maintaining high impact strength.