Polyamide acid solution and preparation method thereof

Abstract

The invention discloses a polyamide acid solution and a preparation method thereof. The method comprises the following steps: dissolving a 4,4'-diamino diphenyl ether monomer, and one or more of 2,2'-bis[4-(4-aminophenoxyphenyl)]propane, 1,3'-bis(4-aminophenoxyl)benzene and 1,4'-bis(4-aminophenoxyl)benzene into a solvent according to the mole ratio ranging from (1 to 1) to (1 to 5); adding pyromellitic dianhydride at 0 to 5 DEG C under the protection of a nitrogen atmosphere; controlling the mole ratio of the pyromellitic dianhydride to amino to be in a range from (1 to 1) to (1.02 to 1); continually stirring; then adding maleic anhydride and controlling the mole ratio of the pyromellitic dianhydride to the maleic anhydride to be in a range from (1 to 0.01) to (1 to 0.05); continually stirring to obtain the polyamide acid solution. The polyamide acid solution disclosed by the invention has adjustable and stable viscosity and a polyimide thin film with a low dielectric constant can be obtained after the polyamide acid solution is subjected to heat treatment; the thin film has excellent mechanical properties and thermal properties and raw materials are easy to obtain and produce.

Description

technical field [0001] The invention belongs to the technical field of preparation and modification of organic polymer materials, and in particular relates to a polyamic acid solution and a preparation method thereof. Background technique [0002] Polyimide is a kind of polymer whose main chain contains imide structure, including straight-chain type and ring-chain type; among them, the mechanical and thermal properties of ring-chain polyimide are outstanding, and the fields of research and use are extensive. Because polyimide has good dielectric properties, thermal properties and mechanical properties, it is widely used in the field of microelectronics manufacturing, including: interlayer insulation materials for multilayer wiring, passivation and packaging materials for chip surfaces, and flexible Base material for printed circuit boards. As an interlayer insulating material, polyimide not only has good dielectric properties, but also has excellent thermal properties, mech...

AI Technical Summary

Problems solved by technology

As an interlayer insulating material, the traditional polyimide has a dielectric constant of 3 or more, which does not meet the current and future dielectric application requirements of large-scale integrated circuit production in the field of microelectronics manufacturing. Therefore, it is necessary to invent a dielectric constant Polyimide close to 2; by making mesoporous materials, adding bulky groups to the molecular structure, increasing the symmetrical structure and doping fluorine elements are all effective ways to reduce the dielectric constant of polyimide, but making Mesoporous materials or fluorine doping to reduce the dielectric constant have limitations: Chinese patent CN 104788676 A discloses a method for preparing a low dielectric constant polyimide / multilayer graphene oxide composite film. Graphene is used to reduce the dielectric constant of the composite film, but graphene oxide is prone to agglomeration when mixed with polyamic acid solution, so that there is a stress concentration phenomenon inside the formed polyimide / multilayer graphene oxide composite film, resulting in Its mechanical properties deteriorate

Chinese patent CN 105601923 A discloses a fluorine-containing soft-hard block polyimide film and its preparation method and application. The film includes flexible fluorine-containing aromatic diamine, aromatic dianhydride-1, rigid aromatic diamine And its preparation method of rigid aromatic dianhydride is to adopt flexible fluorine-containing aromatic diamine to prepare fluorine-containing soft-hard block polyamic acid resin solution, and then form polyimide film finally by solvent removal and imidization, but The preparation of fluorine-containing monomers is difficult and difficult to obtain, resulting in high manufacturing costs and limited application fields

Images