Electrical Insulation Paper, Methods of Manufacture, and Articles Manufactured Therefrom

摘要

Fibrous substrates containing polyetherimides and other synthetic fibers are disclosed, along with methods of preparing electrical insulation paper and articles comprising the fibrous substrates.

主权项

1. A fibrous substrate comprising a consolidated product of a fiber composition comprising, based on the total weight of fibers in the fiber composition:
35 to 70 wt. % of polyimide fibers; at least 5 wt. % of aromatic polyamide fibrids; 20 to 30 wt. % of liquid crystal polymer fibers having a length of 3 to 6 mm, and a linear mass density of 1.7 to 2.8 dtex; each based on the total weight of the fibers in the fiber composition; wherein the fibrous substrate has a thickness of more than 0 to less than 800 μm; wherein the substrate has: (1) electrical breakdown strength of at least 600 Volt/mil; (2) thermal capabilit exceeding the standards for NEMA Class F (155° C.) and NEMA Class H (180° C.) insulation, and has 5 or less wt. % gain due to water saturation at 100% Relative Humidity; (3) tear strength, measured as Elmendorf tear strength of at least 85 mN; and (4) resistivity of at least 1,000 MOhm-cm.