摘要:
Provided are: an electrically insulating resin sheet for motors, which is used for achieving the insulation between coil wires or between a coil wire and an iron core in a motor, and which has high heat resistance, high electrical insulation performance and a high insulation breakdown voltage; and a process for producing the electrically insulating resin sheet. The electrically insulating resin sheet for motors, which is provided with a porous resin layer comprising a thermoplastic resin, is characterized in that the resin sheet has a relative permittivity of 2.0 or less at 1 GHz. It is preferred that the porous resin layer has an average cell diameter of 5.0 µm or less and contains cells in such an amount that the porosity is 30 % or more.
摘要:
Provided are: a polyetherimide porous body which has a fine cell structure, a low relative permittivity and a high insulation breakdown voltage; and a method for producing the same. This polyetherimide porous body comprises a crosslinked body in which a polyetherimide having a specific repeated structural unit is ring-opened and crosslinked with a polyamine compound.
摘要:
Provided are: a polyetherimide porous body which has a low relative permittivity and is not easily cracked (or is excellent in cracking resistance) when folded, and a method for producing the porous body. This polyetherimide porous body comprises a polyetherimide crosslinked body and has a gel fraction of 10 % or more, an average cell diameter of 8 µm or less, a volume porosity of 30 % or more and an insulation breakdown voltage of 30 kV/mm or more.