Polymer compositions and substrates for high temperature transparent conductive film applications

Patent metadata

Field	Value
Publication number	US-2017190903-A1
Application number	US-201615285767-A
Country	US
Kind code	A1
Filing date	Oct 5, 2016
Priority date	Nov 24, 2015
Publication date	Jul 6, 2017
Grant date	—

Abstract

Described are polymer compositions that include a blend of copolyester polymers based on monomers that include on terephthalic acid (TPA), isophthalic acid (IPA) and 1,4-cyclohexanedimethanol (CHDM), wherein the blend includes a first copolyester that is semi-crystalline and a second copolyester that is amorphous; and films made from the polymer compositions useful for transparent high temperature conductive film applications.

First claim

We claim:

1 . A polymer composition comprising a blend of a first PCTA copolyester and a second PCTA copolyester,
said first PCTA copolyester comprising: (a) diacid residues comprising from about 90 to about 99 mole percent of terephthalic acid (TPA) residues and from about 1 to about 10 mole percent isophthalic acid (IPA) residues; and (b) diol residues comprising at least 85 mole percent of 1,4-cyclohexanedimethanol (CHDM) residues, wherein the first PCTA copolyester comprises a total of 100 mole percent diacid residues and a total of 100 mole percent diol residues; said second PCTA copolyester comprising: (a) diacid residues comprising from about 60 to about 90 mole percent of TPA residues and from about 10 to about 40 mole percent IPA residues; and (b) diol residues comprising at least 85 mole percent of CHDM residues, wherein the second PCTA copolyester comprises a total of 100 mole percent diacid residues and a total of 100 mole percent diol residues; wherein the first PCTA copolyester is semi-crystalline; wherein the second PCTA copolyester is amorphous; and wherein the blend comprises diacid residues comprising from about 5 to about 20 net mole percent of IPA residues, wherein the blend comprises a total of 100 mole percent diacid residues and a total of 100 mole percent diol residues.

2 . The polymer composition according to claim 1 , wherein the first PCTA copolyester comprises diacid residues comprising from 3 to 7 mole percent IPA residues.

3 . The polymer composition according to claim 2 , wherein the second PCTA copolyester comprises diacid residues comprising from 20 to 30 mole percent IPA residues.

4 . The polymer composition according to claim 3 , wherein the first PCTA copolyester and second PCTA copolyester each comprise diol residues comprising 100 mole percent CHDM residues.

5 . The polymer composition according to claim 1 , wherein the first PCTA copolyester has a degree of crystallinity of about 40% or greater.

6 . The polymer composition according to claim 1 , wherein the second PCTA copolyester is capable of being crystallized by heating or stretching.

7 . The polymer composition according to claim 1 , wherein the blend comprises diacid residues comprising from about 7 to about 12 net mole percent of IPA residues, wherein the blend comprises a total of 100 mole percent diacid residues and a total of 100 mole percent diol residues.

8 . The polymer composition according to claim 1 , wherein the blend comprises the first PCTA polyester in an amount from about 70 to about 80 wt % and the second PCTA polyester in an amount from about 20 to about 30 wt %.

9 . The polymer composition according to claim 1 , wherein the blend comprises less than 2 wt % of any additional additives.

10 . The polymer composition according to claim 1 , wherein the blend has a T g of at least 85° C., and a T m of at least 255° C.

11 . A polyester film comprising a melt formed polyester blend, wherein said polyester blend comprises a first PCTA copolyester and a second PCTA copolyester,
said first PCTA copolyester comprising: (a) diacid residues comprising from about 90 to about 99 mole percent of terephthalic acid (TPA) residues and from about 1 to about 10 mole percent isophthalic acid (IPA) residues; and (b) diol residues comprising at least 85 mole percent of 1,4-cyclohexanedimethanol (CHDM) residues, wherein the first PCTA copolyester comprises a total of 100 mole percent diacid residues and a total of 100 mole percent diol residues; said second PCTA copolyester comprising: (a) diacid residues comprising from about 60 to about 90 mole percent of TPA residues and from about 10 to about 40 mole percent IPA residues; and (b) diol residues comprising at least 85 mole percent of CHDM residues, wherein the second PCTA copolyester comprises a total of 100 mole percent diacid residues and a total of 100 mole percent diol residues; wherein the first PCTA copolyester is semi-crystalline; wherein the second PCTA copolyester is amorphous; wherein said blend comprises diacid residues comprising from about 5 to about 20 net mole percent of IPA residues, wherein the blend comprises a total of 100 mole percent diacid residues and a total of 100 mole percent diol residues; and wherein the film has a thickness in the range from about 25 to about 250 microns.

12 . The polyester film according to claim 11 , wherein the film has an IV greater than 0.7 dL/g.

13 . The polyester film according to claim 11 , wherein said polyester film is biaxially oriented and has a haze of less than 1%.

14 . The polyester film according to claim 13 , wherein the polyester film is capable of being annealed at a temperature of 150° C. for 90 minutes and maintaining a haze of less than 1%.

15 . The polyester film according to claim 11 , further comprising an ITO coating and having a sheet resistance of less than about 100 Ω/□.

16 . A method of making a biaxially oriented polyester film, said method comprising blending a first PCTA copolyester and a second PCTA copolyester; forming a melt processable polymer composition from the blend; melt forming the melt processable polymer composition to form a sheet; and biaxially stretching the sheet to form a film, wherein said polyester blend comprises a first PCTA copolyester and a second PCTA copolyester,
said first PCTA copolyester comprising: (a) diacid residues comprising from about 90 to about 99 mole percent of terephthalic acid (TPA) residues and from about 1 to about 10 mole percent isophthalic acid (IPA) residues; and (b) diol residues comprising at least 85 mole percent of 1,4-cyclohexanedimethanol (CHDM) residues, wherein the first PCTA copolyester comprises a total of 100 mole percent diacid residues and a total of 100 mole percent diol residues; said second PCTA copolyester comprising: (a) diacid residues comprising from about 60 to about 90 mole percent of TPA residues and from about 10 to about 40 mole percent IPA residues; and (b) diol residues comprising at least 90 mole percent of CHDM residues, wherein the second PCTA copolyester comprises a total of 100 mole percent diacid residues and a total of 100 mole percent diol residues; wherein the first PCTA copolyester is semi-crystalline; wherein the second PCTA copolyester is amorphous; wherein said blend comprises diacid residues comprising from about 5 to about 20 net mole percent of IPA residues, wherein the blend comprises a total of 100 mole percent diacid residues and a total of 100 mole percent diol residues.

17 . The method according to claim 16 , wherein the blend comprises diacid residues comprising from about 7 to about 12 net mole percent of IPA residues, wherein the blend comprises a total of 100 mole percent diacid residues and a total of 100 mole percent diol residues.

18 . The method according to claim 16 , wherein the melt forming step comprises extruding the blend at a temperature at or below 580° F. (304° C.) using an extruder, and wherein the motor load on the extruder is lower for the blend compared to extruding only the first PCTA polymer under similar conditions.

19 . The method according to claim 16 , wherein the polyester film has a haze of less than 1%.

20 . The method according to claim 19 , wherein the polyester film is capable of being annealed at a temperature of 150° C. for 90 minutes and maintaining a haze of less than 1%.

Assignees

• Eastman Chem Co

Inventors

• Shih Wayne Ken

Classifications

• B29K2067/00

  Use of polyesters {or derivatives thereof}, as moulding material · CPC title

• B29C48/022

  characterised by the choice of material · CPC title

• C08J2467/02

  Polyesters derived from dicarboxylic acids and dihydroxy compounds (C08J2467/06 takes precedence) · CPC title

• B29C48/001

  Combinations of extrusion moulding with other shaping operations · CPC title

• C08L67/02 Primary

  Polyesters derived from dicarboxylic acids and dihydroxy compounds (C08L67/06 takes precedence) · CPC title