English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

In this paper, a series of polyimide films were prepares through a novel precursor pre-imidized poly (amic acid) ammonium salt (PI-PAAS). The chemical structure of PI-PAAS films was confirmed by 1H NMR, and the degree of pre-imidization was confirmed by FT-IR spectra. And the intrinsic viscosity of the PI-PAAS solution was not distinctly changed after 90 days, while the viscosity of poly (amic acid) (PAA) obviously decreased with storage time. It was suggested that hydrolytic stability of PI-PAAS was significantly improved as compared with that of PAA due to the shielded carboxyl groups on PI-PAAS, which prevented the molecular chain of the polymer from decomposition. Moreover, PI films derived from PI-PAAS precursors possessed superior mechanical properties.

Preparation of Polyimide Films Derived from a Novel Precursor Pre-imidized Poly (amic acid) Ammonium Salt