POLYESTER-POLYCARBONATE COPOLYMER AND METHOD FOR PRODUCING SAME

Abstract

Polycarbonate block copolymers are provided, which have: (A) a polyester block of chemical formula 1; and (B) a polycarbonate block derived from a dihydric phenol of chemical formula 3 compound and phosgene. The copolymers may be prepared by (1) polymerizing ester oligomers to form a compound of chemical formula 1; and (2) copolymerizing the ester oligomer obtained in (1) with a polycarbonate oligomer prepared from a dihydric phenol compound of chemical formula 3 and phosgene, in the presence of a polymerization catalyst. The block copolymer may have a viscosity average molecular weight (Mv) of 10,000 to 200,000. The thermoplastic copolymer resins have excellent heat resistance, transparency, impact strength, and fluidity, and thus can be usefully applied in various products, including office devices, electric/electronic products, and automotive interior/exterior parts;

##STR00001##

Claims

1. A polycarbonate block copolymer comprising, as repeating units, (A) a polyester block having a structure represented by the following chemical formula 1; and (B) a polycarbonate block: ##STR00011## wherein, in the above chemical formula 1, R.sub.1 independently represents hydrogen atom, alkyl, cycloalkyl, cycloalkylalkyl or aryl; X independently represents oxygen or NRR, where R.sub.2 independently represents hydrogen atom, alkyl, cycloalkyl, cycloalkylalkyl or aryl; R.sub.3 independently represents alkyl, cycloalkyl, cycloalkylalkyl or aryl; and m is independently an integer of 2 to 50.

2. The polycarbonate block copolymer of claim I , wherein the polyester block having a structure represented by chemical formula 1 is derived from an ester oligomer prepared by condensation reaction of a compound represented by the following chemical formula 2-1 and a compound represented by the following chemical formula 2-2: ##STR00012## wherein, in the above chemical formulas 2-1 and 2-2, R.sub.1 independently represents hydrogen atom, alkyl having 1 to 4 carbons, cycloalkyl having 3 to 6 carbons, cycloalkylalkyl having 4 to 10 carbons or aryl having 6 to 10 carbons; X independently represents oxygen or NR.sub.2, where R.sub.2 independently represents hydrogen atom, alkyl having 1 to 4 carbons, cycloalkyl having 3 to 6 carbons, cycloalkylalkyl having 4 to 10 carbons or aryl having 6 to 10 carbons; Y independently represents hydroxyl or halogen atom; and R.sub.3 independently represents alkyl having 1 to 10 carbons, cycloalkyl having 3 to 6 carbons, cycloalkylalkyl having 4 to 10 carbons or aryl having 6 to 10 carbons.

3. The polycarbonate block copolymer of claim 2, wherein the reaction molar ratio of a compound of chemical formula 2-1 to a compound of chemical formula 2-2 is 1:0.5 to 1:2.

4. The polycarbonate block copolymer of claim 2, wherein the ester oligomer has a number average molecular weight of 500 to 20,000 g/mol.

5. The polycarbonate block copolymer of claim 1, wherein the polycarbonate block is derived from a polycarbonate oligomer prepared by a phosgene method using a dihydric phenol compound and phosgene.

6. The polycarbonate block copolymer of claim 5, wherein the dihydric phenol compound is bisphenol A.

7. The polycarbonate block copolymer of claim 5, wherein the polycarbonate oligomer has a viscosity average molecular weight of 1,000 to 20,000.

8. The polycarbonate block copolymer of claim 1, wherein the amount of the polyester block (A) having a structure represented by chemical formula 1 is 0.5 to 50 mol %, based on the total moles of the monomer compounds constituting the copolymer as 100 mol %.

9. The polycarbonate block copolymer of claim 1, which has a viscosity average molecular weight (Mv) of 10,000 to 200,000.

10. A method for preparing a polycarbonate block copolymer, comprising the steps of: (1) polymerizing an ester oligomer by condensation reaction of a compound represented by the following chemical formula 2-1 and a compound represented by the following chemical formula 2-2; and (2) copolymerizing the ester oligomer obtained in the above step (1) and polycarbonate in the presence of a polymerization catalyst: ##STR00013## wherein, in the above chemical formulas 2-1 and 2-2, R.sub.1 independently represents hydrogen atom, alkyl having 1 to 4 carbons, cycloalkyl having 3 to 6 carbons, cycloalkylalkyl having 4 to 10 carbons or aryl having 6 to 10 carbons; X independently represents oxygen or NR.sub.2, where R.sub.2 independently represents hydrogen atom, alkyl having 1 to 4 carbons, cycloalkyl having 3 to 6 carbons, cycloalkylalkyl having 4 to 10 carbons or aryl having 6 to 10 carbons; Y independently represents hydroxyl or halogen atom; and R.sub.3 independently represents alkyl having 1 to 10 carbons, cycloalkyl having 3 to 6 carbons, cycloalkylalkyl having 4 to 10 carbons or aryl having 6 to 10 carbons.

11. A molded article comprising the polycarbonate block copolymer of claim 1.

12. The molded article of claim 11, which is an optical material or an automotive part.

Description

EXAMPLES

Preparation Example 1

Preparation of Ester Oligomer of Chemical Formula 7

[0065] In a 500 mL three-necked flask, phenolphthaleine of chemical formula 5 (30 mmol), terephthaloyl chloride of chemical formula 6 (20 mmol) and 200 mL of tetrahydrofuran were added, and 20 g of triethylamine (TEA) was slowly added thereto under nitrogen atmosphere at 25° C., and the resulting mixture was agitated for 12 hours. The generated precipitate was washed with distilled water and methanol, and dried in a vacuum oven for 24 hours to obtain 13.4 g of the ester oligomer of chemical formula 7.

##STR00007##

Preparation Example 2

Preparation of Ester Oligomer of Chemical Formula 8

[0066] In a 500 mL three-necked flask, phenolphthaleine of chemical formula 5 (30 mmol), terephthaloyl chloride of chemical formula 6 (25 mmol) and 200 mL of tetrahydrofuran were added, and 20g of triethylamine (TEA) was slowly added thereto under nitrogen atmosphere at 25° C., and the resulting mixture was agitated for 24 hours. The generated precipitate was washed with distilled water and methanol, and dried in a vacuum oven for 24 hours to obtain 12.5 g of the ester oligomer of chemical formula 8.

##STR00008##

Preparation Example 3

Preparation of Ester Oligomer of Chemical Formula 10

[0067] In a 500 mL three-necked flask, 3,3-bis (4-hydroxyphenyl) phthalimidine (BHPP) of chemical formula 9 (30 mmol), terephthaloyl chloride of chemical formula 6 (20 mmol) and 200 mL of tetrahydrofuran were added, and 20g of triethylamine (TEA) was slowly added thereto under nitrogen atmosphere at 25° C., and the resulting mixture was agitated for 12 hours. The generated precipitate was washed with distilled water and methanol, and dried in a vacuum oven for 24 hours to obtain 13.2 g of the ester oligomer of chemical formula 10.

##STR00009##

Preparation Example 4

Preparation of Ester Oligomer of Chemical Formula 12

[0068] In a 500 mL three-necked flask, N-phenyl 3,3-bis(4-hydroxyphenyl)phthalimidine (PBHPP) of chemical formula 11 (30 mmol), terephthaloyl chloride of chemical formula 6 (20 mmol) and 200 mL of tetrahydrofuran were added, and 20 g of triethylamine (TEA) was slowly added thereto under nitrogen atmosphere at 25° C., and the resulting mixture was agitated for 12 hours. The generated precipitate was washed with distilled water and methanol, and dried in a vacuum oven for 24 hours to obtain 13.8 g of the ester oligomer of chemical formula 12.

##STR00010##

Preparation Example 5

Preparation of Polycarbonate Oligomer

[0069] In a 1 L three-necked flask, 60 g (0.263 mol) of bisphenol A was dissolved in 330 ml of 5.6 wt % aqueous solution of sodium hydroxide (18.46 g, 0.462 mol), and 26.0 g (0.263 mol) of phosgene trapped in methylene chloride was slowly added thereto through teflon tube (20 mm) and reacted. The outside temperature was maintained at 0° C. The reactants, which passed through the tubular reactor, were interfacially reacted under a nitrogen environment for about 10 minutes to prepare an oligomeric polycarbonate having a viscosity average molecular weight of about 1,000. From the mixture containing the prepared oligomeric polycarbonate, 215 mL of organic phase and 322 mL of aqueous phase were collected and mixed with 1.383 g of p-tert-butylphenol (PTBP) (9.21 mmol, 3.5 mol % to bisphenol A), 0.731 g of tetrabutyl ammonium chloride (TBACI) (2.63 mmol, 1 mol % to bisphenol A) and 0.1 mL of 15 wt % aqueous solution of tri-ethylamine (TEA), and reacted for 30 minutes to prepare a polycarbonate oligomer solution.

Preparation Example 6

Preparation of Polycarbonate Oligomer

[0070] In a 1 L three-necked flask, 60 g (0.263 mol) of bisphenol A was dissolved in 330 ml of 5.6 wt % aqueous solution of sodium hydroxide (18.46 g, 0.462 mol), and 26.0 g (0.263 mol) of phosgene trapped in methylene chloride was slowly added thereto through teflon tube (20 mm) and reacted. The outside temperature was maintained at 0° C. The reactants, which passed through the tubular reactor, were interfacially reacted under a nitrogen environment for about 10 minutes to prepare an oligomeric polycarbonate having a viscosity average molecular weight of about 1,000. From the mixture containing the prepared oligomeric polycarbonate, 215 mL of organic phase and 322 mL of aqueous phase were collected and mixed with 0.198 g of p-tert-butylphenol (PTBP) (1.32 mmol, 0.5 mol % to bisphenol A), 0.731 g of tetrabutyl ammonium chloride (TBACI) (2.63 mmol, 1 mol % to bisphenol A) and 0.1 mL of 15 wt % aqueous solution of tri-ethylamine (TEA), and reacted for 30 minutes to prepare a polycarbonate oligomer solution.

Example 1

Preparation of Block Copolymer

[0071] To the polycarbonate oligomer solution prepared in the above Preparation Example 5, 15 g of the compound of the above chemical formula 7 was added. After the phases were separated, only the organic phase was collected and thereto, 283 g of methylene chloride which was the same amount of the organic phase, 110 mL of 1.1 N aqueous solution of sodium hydroxide (20 vol % to the total mixture) and 15 μL of 15 wt % triethylamine were admixed and reacted for 1 hour, and then 167 μL of 15 wt % triethylamine and 128 g of methylene chloride were further added thereto and reacted for additional 1 hour. After phase separation, pure water was added to the viscosity-increased organic phase, and it was washed with alkali and separated. Subsequently, the resulting organic phase was washed with 0.1 N hydrochloric acid solution and then rinsed with distilled water 2 or 3 times repeatedly. After the rinse was completed, the concentration of the organic phase was adjusted constantly and then granulated by using a constant amount of double-distilled water at 76° C. After the granulation was completed, the product was dried first at 110° C. for 8 hours and then at 120° C. for 10 hours to prepare a block copolymer. The properties of the prepared copolymer were measured, and the results are shown in the following Table 1.

Example 2

Preparation of Block Copolymer

[0072] Excepting that 75 g of the compound of chemical formula 7 was used, a block copolymer was prepared by the same method as Example 1. The properties of the prepared copolymer were measured, and the results are shown in the following Table 1.

Example 3

Preparation of Block Copolymer

[0073] Excepting that 30 g of the compound of chemical formula 8 was used instead of the compound of chemical formula 7, a block copolymer was prepared by the same method as Example 1. The properties of the prepared copolymer were measured, and the results are shown in the following Table 1.

Example 4

Preparation of Block Copolymer

[0074] Excepting that 15 g of the compound of chemical formula 10 was used instead of the compound of chemical formula 7, a block copolymer was prepared by the same method as Example 1. The properties of the prepared copolymer were measured, and the results are shown in the following Table 1.

Example 5

Preparation of Block Copolymer

[0075] Excepting that 17 g of the compound of chemical formula 12 was used instead of the compound of chemical formula 7, a block copolymer was prepared by the same method as Example 1. The properties of the prepared copolymer were measured, and the results are shown in the following Table 1.

Example 6

Preparation of Block Copolymer

[0076] Excepting that the polycarbonate oligomer solution prepared in the above Preparation Example 6 was used instead of the polycarbonate oligomer solution prepared in the above Preparation Example 5, a block copolymer was prepared by the same method as Example 1. The properties of the prepared copolymer were measured, and the results are shown in the following Table 1.

Comparative Example 1

[0077] A linear polycarbonate having a viscosity average molecular weight of 21,200 was prepared by a polymerization method using interfacial reaction. The properties of the prepared linear polycarbonate were measured, and the results are shown in the following Table

Comparative Example 2

[0078] A linear polycarbonate having a viscosity average molecular weight of 71,200 was prepared by a polymerization method using interfacial reaction. The properties of the prepared linear polycarbonate were measured, and the results are shown in the following Table

[0079] The values of properties shown in the following Table I are those measured after drying the resins prepared in the above Examples and Comparative Examples at 120° C. for 24 hours. The methods of property measurement were as follows.

[0080] (1) Viscosity average molecular weight: The viscosity of methylene chloride solution was measured by using an Ubbelohde Viscometer at 20° C., and the limiting viscosity [η] was calculated therefrom according to the following equation.

|η|=1.23×10.sup.−5 Mv.sup.0.83

[0081] (2) Impact strength: The impact strength was measured by using an impact tester (RESIL IMPACTOR, CEAST) at room temperature.

[0082] (3) Total transmittance: The total transmittance was measured in accordance with ASTM D1003 using a 3 mm-thick test specimen.

[0083] (4) Glass transition temperature: The glass transition temperature was measured by using a differential scanning calorimeter (DSC-7 & Robotic, Perkin-Elmer).

TABLE-US-00001 TABLE 11 Examples Comparative Examples Properties 1 2 3 4 5 6 1 2 Molecular 21,100 21,300 21,300 21,200 21,000 71,000 21,200 71,100 weight (Mv) Impact strength 75 71 76 73 12 80 79 84 (Kg.sub.fcm/cm.sup.2) Total 89 87 87 87 88 88 89 88 transmittance (%) Glass transition 185 222 211 217 229 188 150 152 temperature (° C.)

[0084] As can be seen from the above Table 1, as compared with the polycarbonates of Comparative Examples, the polycarbonate block copolymers prepared in Examples 1 to 6 according to the present invention showed remarkably superior heat resistance, maintaining impact resistance and transparency at similar levels.