Preparation method of polycyclohexylenedimethylene terephthalate resin having excellent color, and polycyclohexylenedimethylene terephthalate resin prepared by the same

Patent metadata

Field	Value
Publication number	US-9487623-B2
Application number	US-201314430518-A
Country	US
Kind code	B2
Filing date	Sep 24, 2013
Priority date	Sep 24, 2012
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

A preparation method of a polycyclohexylenedimethylene terephthalate resin according to the present invention includes the steps of injecting a titanium compound and a germanium compound as catalysts to a mixture of a diol compound and dicarboxylic acid under stirring and performing esterification reaction and polycondensation reaction, in which the titanium compound is injected in a titanium atom content of 20 ppm or less, based on the weight of the final polycyclohexylenedimethylene terephthalate resin. The preparation method of the polycyclohexylenedimethylene terephthalate resin according to the present invention can be used to prepare a polycyclohexylenedimethylene terephthalate resin that has excellent degree of polymerization, color and light reflectance and has remarkably improved heat stability, and it is suitable to use the polycyclohexylenedimethylene terephthalate resin according to the present invention as an LED housing material.

First claim

What is claimed is:

1. A preparation method of a polycyclohexylenedimethylene terephthalate resin comprising the steps of injecting a titanium compound and a germanium compound as catalysts to a mixture of a diol compound and dicarboxylic acid under stirring and performing esterification reaction and polycondensation reaction, wherein the titanium compound is injected in a titanium atom content of 20 ppm or less, based on the weight of the final polycyclohexylenedimethylene terephthalate resin,
wherein the polycyclohexylenedimethylene terephthalate resin has a color-L value of 87 or higher after heat treatment at 150° C. for 1 hour.

2. The preparation method according to claim 1 , wherein the germanium compound is injected in a germanium atom content of 30 to 1,000 ppm, based on the weight of the final polycyclohexylenedimethylene terephthalate resin.

3. The preparation method according to claim 1 , wherein the diol compound includes cyclohexanedimethanol (CHDM).

4. The preparation method according to claim 3 , wherein the diol compound further includes one or more selected from the group consisting of ethylene glycol, diethylene glycol, 1,4-butanediol, 1,3-propanediol, and neopentyl glycol.

5. The preparation method according to claim 1 , wherein the dicarboxylic acid includes terephthalic acid (TPA) or dimethylterephthalic acid (DMT).

6. The preparation method according to claim 5 , wherein the dicarboxylic acid further includes one or more selected from the group consisting of isophthalic acid (IPA), naphthalene 2,6-dicarboxylic acid (2,6-NDA), dimethylisophthalic acid (DMI), and dimethyl naphthalene 2,6-dicarboxylic acid (2,6-NDC).

7. The preparation method according to claim 1 , wherein the titanium compound is selected from the group consisting of titanium oxide, titanium chelate compound, tetra-n-propyl titanate, tetra-isopropyl titanate, tetra-n-butyl titanate, tetra-isobutyl titanate, and butyl-isopropyl titanate.

8. The preparation method according to claim 1 , wherein the germanium compound is germanium dioxide.

9. The preparation method according to claim 1 , further comprising the step of injecting a phosphorus-based stabilizer.

10. The preparation method according to claim 9 , wherein the phosphorus-based stabilizer is selected from the group consisting of tri-ethyl phosphate, tri-methyl phosphate, tri-phenyl phosphate, tri-ethyl phosphonoacetate, phosphoric acid, and phosphorous acid.

11. A polycyclohexylenedimethylene terephthalate resin that is prepared by the method of claim 1 .

12. The polycyclohexylenedimethylene terephthalate resin according to claim 11 , wherein the polycyclohexylenedimethylene terephthalate resin has an intrinsic viscosity of 1.10 dl/g or less and a color-b value of 4 or lower after heat treatment at 150° C. for 1 hour,
wherein the intrinsic viscosity is calculated by the following correction equation:

[
η
]

=

1
+

4
⁢
A
⁢

⁢

η
sp

-
1

2
⁢
A
⁢

⁢
c

wherein A is the Huggins's constant of 0.247, c is a concentration value of 1.2 g/dL, and η sp is measured using an Ubbelohde viscometer at 35° C. after the polycyclohexylenedimethylene terephthalate resin is dissolved in o-chlorophenol at a concentration of 1.2 g/dL.

13. A polycyclohexylenedimethylene terephthalate resin having a titanium atom content of 20 ppm or less, based on the weight of the final polycyclohexylenedimethylene terephthalate resin,
wherein the polycyclohexylenedimethylene terephthalate resin has a color-L value of 87 or higher after heat treatment at 150° C. for 1 hour.

14. The polycyclohexylenedimethylene terephthalate resin according to claim 13 , further having a germanium atom content of 30 to 1,000 ppm, based on the weight of the final polycyclohexylenedimethylene terephthalate resin.

15. The polycyclohexylenedimethylene terephthalate resin according to claim 13 , further having a phosphorus atom content of 30 ppm or less, based on the weight of the final polycyclohexylenedimethylene terephthalate resin.

16. The polycyclohexylenedimethylene terephthalate resin according to claim 13 , wherein the polycyclohexylenedimethylene terephthalate resin has an intrinsic viscosity of 1.10 dl/g or less and a color-b value of 4 or lower after heat treatment at 150° C. for 1 hour,
wherein the intrinsic viscosity is calculated by the following correction equation:

[
η
]

=

1
+

4
⁢
A
⁢

⁢

η
sp

-
1

2
⁢
A
⁢

⁢
c

wherein A is the Huggins's constant of 0.247, c is a concentration value of 1.2 g/dL, and η sp is measured using an Ubbelohde viscometer at 35° C. after the polycyclohexylenedimethylene terephalate resin is dissolved in o-chlorophenol at a concentration of 1.2 g/dL.

Assignees

• Sk Chemicals Co Ltd

Inventors

• Moon Jung-Me
• Kim Tae-Young
• Kim Jong Ryang

Classifications

• C08G63/199 Primary

  Acids or hydroxy compounds containing cycloaliphatic rings · CPC title

• C08G63/85

  Germanium, tin, lead, arsenic, antimony, bismuth, titanium, zirconium, hafnium, vanadium, niobium, tantalum, or compounds thereof {(C08G63/823 takes precedence)} · CPC title

• C08G63/183

  Terephthalic acids · CPC title

• C08G63/863 Primary

  Germanium or compounds thereof · CPC title

• C08L67/03

  the dicarboxylic acids and dihydroxy compounds having the carboxyl- and the hydroxy groups directly linked to aromatic rings · CPC title