Method of preparing polycarbonate resin

• US 7,495,065 B2
• Filed: 03/06/2006
• Issued: 02/24/2009
• Est. Priority Date: 03/07/2005
• Status: Active Grant

• Current Assignee: LG Chem Limited (LG Corporation)
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: Hong, Mijeung, Park, Sung Kyou, Kim, Jong Hun, Woo, Boo Gon
• Primary Examiner(s): Boykin; Terressa M
• Application Number:
  US11/368,568
• Publication Number:
  US 20060199940A1
• Time in Patent Office: 1,086 Days
• Field of Search: 528/196, 528/198, 528/199
• US Class Current: 528/198
• CPC Class Codes: C08G 64/14 containing a chain-terminating or -crosslinking agent
• CPC Class Codes: C08G 64/42 Chemical after-treatment

Abstract

A method of preparing a polycarbonate resin having improved thermal stability is provided. The method includes: mixing polycarbonate having hydroxy terminal groups and a end terminator, a compound of formula (1) (refer to the detailed description section) at normal temperature and pressure to obtain a mixture; and performing a melt reaction on the mixture at 250-320° C. and reduced pressure to highly reduce the final concentration of the hydroxy terminal groups of the polycarbonate resin.

Claims

1. A method of preparing an end-capped polycarbonate resin comprising:

mixing a polycarbonate having hydroxy terminal groups and a compound of formula (1)

2. The method of claim 1, wherein the step of melt reacting is performed at a reduced pressure of 5-500 mmHg.

3. The method of claim 1, wherein the amount of said compound of formula (1) is in the range of 0.5-20 moles with respect to 1 mole of said polycarbonate.

4. The method of claim 1, wherein the final concentration of said hydroxy terminal groups of said polycarbonate resin is in the range of 0-4.7 mol % of the total terminal groups of said polycarbonate resin.

5. A polycarbonate resin prepared using the method of claim 1.

6. The polycarbonate resin of claim 5, wherein the final concentration of said hydroxy terminal groups of said polycarbonate resin is in the range of 0-4.7 mol % of the total terminal groups of said polycarbonate resin.

13. The method of claim 1, wherein the final concentration of said hydroxy terminal groups of said polycarbonate resin is in the range of 0-25 mol % of the total terminal groups of said polycarbonate resin.

14. The polycarbonate resin of claim 5, wherein the final concentration of said hydroxy terminal groups of said polycarbonate resin is in the range of 0-25 mol % of the total terminal groups of said polycarbonate resin.

7. A mixed resin comprising a polycarbonate having hydroxy terminal groups and a compound of formula (1)

8. The mixed resin of claim 7, wherein the amount of said compound of formula (1) is in the range of 0.5-20 moles with respect to 1 mole of said polycarbonate.

9. The mixed resin of claim 7, wherein the final concentration of said hydroxy terminal groups of said polycarbonate resin is in the range of 0-4.7 mol % of the total terminal group of said mixed resin.

15. The mixed resin of claim 7, wherein the final concentration of said hydroxy terminal groups of said polycarbonate resin is in the range of 0-25 mol % of the total terminal group of said mixed resin.

10. An end-capped polycarbonate resin comprising a reaction mixture of a polycarbonate having hydroxy terminal groups and a compound of formula (1)

11. The end-capped resin of claim 10, wherein the amount of said compound of formula (1) is in the range of 0.5-20 moles with respect to 1 mole of said polycarbonate.

12. The end-capped resin of claim 11, wherein the final concentration of said hydroxy terminal groups of said polycarbonate resin is in the range of 0-4.7 mol % of the total terminal group of said end-capped resin.

16. The end-capped resin of claim 11, wherein the final concentration of said hydroxy terminal groups of said polycarbonate resin is in the range of 0-25 mol % of the total terminal group of said end-capped resin.