| 摘要 |
PURPOSE: To readily obtain the subject dense and homogeneous shaped article excellent in thermal and mechanical characteristics and shapable even when formed into a thin sheet of a uniform thickness by heating, pressing and shaping a sheet-like structure comprising specific polyimide fibers under specific conditions. CONSTITUTION: This flame retardant and high-temperature resistant shaped article is obtained by initially providing a manipulatable sheet-like structure such as a nonwoven fabric using polyimide fibers of formula I (n is a natural number; A is a tetravalent aromatic group selected from formula II, III or the like; R is a bivalent aromatic group selected from formula IV, V or the like), then pressing and shaping the resultant structure under heating at a temperature within the glass transition range of 280-360 deg.C, preferably 310-360 deg.C under a pressure within the range of 10-500 bar, preferably 10-350 bar. The resultant shaped article comprises the polyimide fibers of formula I and has >=1.3 g/cm<3> density. |
