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CN-121986132-A - Polyimide film having improved physical properties and appearance without using p-phenylenediamine and method for preparing the same

CN121986132ACN 121986132 ACN121986132 ACN 121986132ACN-121986132-A

Abstract

Provided is a polyimide film including a block copolymer including a dianhydride monomer including pyromellitic dianhydride (PMDA) and a diamine monomer including 4,4' -diaminodiphenyl ether (ODA) and m-tolidine (m-TD), wherein a water absorption measured after at least one day of storage in water at room temperature (20 ℃ to 25 ℃) is 2.5% or less and a water absorption measured after at least one day of storage in a constant temperature and humidity chamber (temperature 25 ℃ humidity 50%) is 1.5% or less.

Inventors

  • Jin Duimin
  • JIN DONGYING
  • Bai Chenglie

Assignees

  • 聚酰亚胺尖端素材株式会社

Dates

Publication Date
20260505
Application Date
20241007
Priority Date
20231011

Claims (17)

  1. 1. A polyimide film comprising: a block copolymer comprising dianhydride monomers including pyromellitic dianhydride (PMDA) and diamine monomers including 4,4' -diaminodiphenyl ether (ODA) and m-tolidine (m-TD), Wherein the water absorption measured after at least one day of storage in water at room temperature (20 ℃ to 25 ℃) is 2.5% or less, The moisture absorption rate measured after at least one day of storage in a constant temperature and humidity chamber (temperature 25 ℃ C., humidity 50%) was 1.5% or less.
  2. 2. The polyimide film according to claim 1, wherein the polyimide has a dielectric dissipation factor (D f , 10 GHz) of 0.015 or less.
  3. 3. The polyimide film of claim 1, wherein the block copolymer has two or more blocks.
  4. 4. The polyimide film of claim 3 wherein the block copolymer comprises a first block and a second block, A dianhydride monomer including pyromellitic dianhydride (PMDA) in the first block is copolymerized with a diamine monomer including m-toluidine (m-TD); Dianhydride monomers including pyromellitic dianhydride (PMDA) in the second block are copolymerized with diamine monomers including 4,4' -diaminodiphenyl ether (ODA).
  5. 5. The polyimide film of claim 1, wherein the amount of m-tolidine (m-TD) in the total diamine monomers of the block copolymer is 40 mol% to 80 mol%.
  6. 6. The polyimide film of claim 1, wherein the amount of 4,4' -diaminodiphenyl ether (ODA) in the total diamine monomers of the block copolymer is 20 mol% to 60 mol%.
  7. 7. The polyimide film of claim 1, wherein the polyimide film has a Transverse Direction (TD) coefficient of thermal expansion (CTE TD ) of-5 ppm/°c to 2.5 ppm/°c.
  8. 8. The polyimide film of claim 1, wherein the polyimide film has a difference (CTE MD -CTE TD ) between the Machine Direction (MD) coefficient of thermal expansion (CTE MD ) and the Transverse Direction (TD) coefficient of thermal expansion (CTE TD ) of-3 ppm/°c to 3 ppm/°c.
  9. 9. The polyimide film of claim 1, wherein the polyimide film has an average coefficient of thermal expansion (CTE Ave ) of-4.25 ppm/°c to 3.0 ppm/°c; The average coefficient of thermal expansion (CTE Ave ) is the average of the Machine Direction (MD) coefficient of thermal expansion (CTE MD ) and the Transverse Direction (TD) coefficient of thermal expansion (CTE TD ) of the polyimide film.
  10. 10. The polyimide film according to claim 1, wherein the polyimide film has a glass transition temperature (Tg) of 380 ℃ or more.
  11. 11. The polyimide film of claim 1, wherein the polyimide film has a modulus of 8 GPa or higher.
  12. 12. The polyimide film of claim 1, wherein the polyimide film has a coefficient of hygroscopic expansion of 3 ppm/rh% to 6 ppm/rh%.
  13. 13. The polyimide film of claim 1, wherein the polyimide film has a thickness of 1 μιη to 100 μιη.
  14. 14. A method of making a polyimide film comprising: Preparing a block copolymer comprising dianhydride monomers including pyromellitic dianhydride (PMDA) and diamine monomers including 4,4' -diaminodiphenyl ether (ODA) and m-toluidine (m-TD), Wherein the water absorption measured after at least one day of storage in water at room temperature (20 ℃ to 25 ℃) is 2.5% or less, The moisture absorption rate measured after at least one day of storage in a constant temperature and humidity chamber (temperature 25 ℃ C., humidity 50%) was 1.5% or less.
  15. 15. The method of claim 14, wherein the preparation of the block copolymer comprises: preparing a first block by polymerizing dianhydride monomers including pyromellitic dianhydride (PMDA) and diamine monomers including m-toluidine (m-TD), and The second block is prepared by polymerizing dianhydride monomers including pyromellitic dianhydride (PMDA) and diamine monomers including 4,4' -diaminodiphenyl ether (ODA).
  16. 16. The method of claim 15, wherein in the preparation of the first block, The amount of the diamine monomer including the m-tolidine (m-TD) is 40 mol% to 80 mol%, The amount of the dianhydride monomer including the pyromellitic dianhydride (PMDA) is 20 mol% to 70 mol%, The ratio (M m-TD /M 1st PMDA ) of the amount of diamine monomer (M m-TD ) comprising M-tolidine (M-TD) to the amount of dianhydride monomer (M 1st PMDA ) comprising pyromellitic dianhydride (PMDA) is greater than 1 and less than 2.
  17. 17. The method of claim 15, wherein in the preparation of the second block, The amount of the diamine monomer including the 4,4' -diaminodiphenyl ether (ODA) is 20 mol% to 60 mol%, The amount of the dianhydride monomer including the pyromellitic dianhydride (PMDA) is 30 mol% to 80 mol%.

Description

Polyimide film having improved physical properties and appearance without using p-phenylenediamine and method for preparing the same Technical Field The present invention relates to a polyimide film having improved physical properties and appearance without using p-phenylenediamine, and a method for preparing the same. Specifically, the present invention relates to a polyimide film having excellent water absorption resistance and moisture absorption resistance without using p-phenylenediamine (p-PHENYLENEDIAMINE, PPD), and low dielectric loss characteristics, and a method for preparing the same. Background Polyimide (PI) is a polyimide ring-based polymer material having excellent chemical stability and a rigid aromatic main chain, and has highest levels of heat resistance, chemical resistance, electrical insulation, chemical resistance and weather resistance among organic materials. In general, a Polyimide (PI) film is a film made of a polyimide resin, which refers to a highly heat-resistant resin, obtained by solution-polymerizing an aromatic dianhydride and an aromatic diamine or an aromatic diisocyanate to prepare a polyamic acid derivative, followed by ring-closure dehydration and imidization at high temperature. Conventional polyimide resins mainly use p-phenylenediamine (PPD) as an aromatic diamine, but PPD causes foaming and gel formation during film preparation, resulting in low productivity and process efficiency. In addition, when a low thermal expansion coefficient is required, there is a problem in that chemical resistance is poor, etc., although a large amount of PPD is used. Therefore, there is a need for development of a polyimide film which has excellent water absorption resistance and moisture absorption resistance even without using p-phenylenediamine, and which has low dielectric loss characteristics after imidization. Disclosure of Invention Technical problem An object of the present invention is to provide a polyimide film which is excellent in water absorption resistance and moisture absorption resistance without using p-phenylenediamine (PPD) and has low dielectric loss characteristics after imidization, and a method for producing the same. Further, another object of the present invention is to provide a display device including the polyimide film. Technical proposal Various modifications may be made and various embodiments may be practiced in the present invention, and specific embodiments are shown in the drawings and described in detail. However, these embodiments are not intended to limit the invention to the particular embodiments and should be construed to include all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. The terminology used in the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as "comprises" or "comprising" are intended to mean the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and should not be understood to exclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof. When an amount, concentration, or other value or parameter is given herein as either a range, preferred range, or a list of upper values of the desired value and lower values of the desired value, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. Where numerical ranges are described herein, unless otherwise stated, it is intended that the endpoints of the ranges and the scope of the invention within the ranges are not limited to the specific values recited in defining the ranges. As used herein, "dianhydride" is intended to include precursors or derivatives thereof, also referred to as "dianhydride" or "acid dianhydride (ACID DIANHYDRIDE)". These products may not be technically dianhydrides, but still react with diamines to form polyamic acids, and the polyamic acids can be converted back to polyimides. As used herein, "diamine" is intended to include precursors or derivatives thereof, which may not be diamine in the art, but still react with dianhydride acid to form a polyamic acid, and the polyamic acid may be converted back to polyimide. Furthermore, unless defined otherwise, all terms, including technical or scientific terms, used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning that is consistent with their meaning in