| 摘要 |
The present invention relates to a transparent polyimide film with improved tensile strength and a preparation method thereof, and more specifically to a colorless, transparent polyimide film having excellent optical properties and improved tear strength at the same time through the use of a monomer containing a functional group or an improver for improving tensile strength, and a preparation method thereof, wherein the functional group is selected from the group consisting of a hexafluoro group, a sulfone group, and an oxy group. |
| 主权项 |
1. A method of preparing a transparent polyimide film, comprising the steps of:
copolymerizing an aromatic dianhydride and a diamine to obtain a polyamic acid; casting the polyamic acid on a support to imidize the polyamic acid; and introducing polyphenylsilsesquioxane as an additive for improving tear strength before or after obtaining the polyamic acid, wherein the aromatic dianhydride is at least one selected from the group consisting of 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic anhydride, pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, biphenyltetracarboxylic dianhydride, and biscarboxyphenyl dimethyl silane dianhydride, wherein the aromatic dianhydride necessarily includes the 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride; and the diamine is at least one selected from the group consisting of oxydianiline, p-phenylenediamine, m-phenylenediamine, p-methylenedianiline, m-methylenedianiline, bistrifluoromethyl benzidine, cyclohexane-1,3-diamine, cyclohexane-1,4-diamine, and bisaminohydroxy phenyl hexafluoropropane, wherein the aromatic diamine necessarily includes the bistrifluoromethyl benzidine. |
