POLYAMIC ACID AND POLYIMIDE

摘要

Disclosed are a polyamic acid containing not less than 10 mol% of a repeating unit represented by the formula [1] below, and a polyimide represented by the formula [2] below which is obtained from such a polyamic acid. The polyamic acid and polyimide have high heat resistance as shown by a thermal decomposition temperature of not less than 300°C. In addition, the polyamic acid and polyimide have good workability because of their high solubility in solvents, while exhibiting good light transmission. (In the formulae, R<SUP>1</SUP> and R<SUP>2</SUP> independently represent a hydrogen atom or an alkyl group having 1-10 carbon atoms; R<SUP>3</SUP> and R<SUP>4</SUP> independently represent a hydrogen atom, a halogen atom, an alkyl group having 1-10 carbon atoms or a phenyl group, or alternatively R<SUP>3</SUP> and R<SUP>4</SUP> on adjacent carbon atoms may combine together to form a cycloalkyl group having 3-8 carbon atoms or a phenyl group; R<SUP>5</SUP> represents a divalent organic group; and n represents an integer of not less than 2.)