Low dielectric, fluorinated polyimide copolymers
Autor: | Diane M. Stoakley, Anne K. St. Clair, Catharine I. Croall |
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Rok vydání: | 1994 |
Předmět: |
chemistry.chemical_classification
Materials science Polymers and Plastics General Chemistry Dielectric Polymer BPDA Surfaces Coatings and Films chemistry.chemical_compound chemistry Flexural strength Ultimate tensile strength Materials Chemistry Thermal stability Composite material Glass transition Polyimide |
Zdroj: | Journal of Applied Polymer Science. 51:1479-1483 |
ISSN: | 1097-4628 0021-8995 |
Popis: | Copolymers of fluorinated polyimides and 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA) have been prepared as films and composite laminates. The addition of BPDA was used as a means to achieve insolubility, making the polymers suitable as aircraft matrix resins. Glass transition temperatures, thermooxidative stabilities, and tensile strengths were increased with increasing BPDA content in the copolymers. Although the addition of BPDA did increase the UV cutoff and decrease the percent transmission slightly, the optical transparency of the polymers was still excellent. Dielectric constants of the copolyimide films ranged from 2.6 to 2.9. Astroquartz II laminates made with these resins had dielectric constant of 3.3–3.4. Flexural strength on unidirectional specimens were in the 1.24–1.41 GPa range and flexural moduli were 41 GPa. © 1994 John Wiley & Sons, Inc.1 |
Databáze: | OpenAIRE |
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