Can I read Effect of isothermal aging on post-imidization and glass transition temperature of LaRC-IA polyimide resin on EtoBox?

Effect of isothermal aging on post-imidization and glass transition temperature of LaRC-IA polyimide resin by Kelvin M. Jordan; Jude O. Iroh is a Materials Science article available to read on EtoBox.

What is Effect of isothermal aging on post-imidization and glass transition temperature of LaRC-IA polyimide resin about?

## Abstract The isothermal aging of partilly imidized NASA Langley Research Center, LaRC‐IA polymide resin containing 70 wt% N‐methyl pyrrolidone, NMP was performed in a vacuum oven at 65, 95, 135, 165 and 200°C for 0.5, 1.0, 1.5 and 2 h. The weight loss and chemical changes that occurred during aging was determined gravimetrically and by FTIR spectroscopy, respectively. The imide absorption peak at 1778 cm^−1^, increased in intensity as the aging temperature was increased from 65 to 200°C. The expulsion of NMP (70 wt%) was completed after ∼2.5 h of aging at 135°C. Additional weight loss ≤4 wt%, after the expulsion of NMP, was attributed to post‐imidization. The imide carbonyl peak absorption at 1721 and 1778 cm^−1^, respectively, were broadened after aging at 200°C. The broadening of the imide absorption peaks was marked by the disappearance of the amide peak near 1660 cm^−1^ and is attributable to post‐imidization of the partially imidized polyamic‐acid. Dissolution of the polyimide aged at T ≥ 165°C in dimethyl formamide, DMF, was unsuccessful even after long times of stirring (∼12 h) at elevated temperature (T ∼ 85°C). The DSC thermogram for the LaRC‐IA resin showed a series of

Who reads Effect of isothermal aging on post-imidization and glass transition temperature of LaRC-IA polyimide resin?

Author

Kelvin M. Jordan; Jude O. Iroh

Publisher

Society for Plastic Engineers; Wiley (John Wiley & Sons); John Wiley & Sons Inc.; Wiley (ISSN 0272-8397)

Published

1997

Language

EN

Field

Materials Science (Physical Sciences)