Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
The structures of aromatic PI systems leading to non- or slightly colored films. 6FDA = 4,4′-(hexafluoroisopropylidene)diphthalic anhydride, s-ODPA = 4,4′-oxydiphthalic anhydride, a-ODPA = 3,4′-oxydiphthalic anhydride, s-BPDA = 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 4,4′-DDS = 4,4′-diaminodiphenylsulfone, 3,3′-DDS = 3,3′-diaminodiphenylsulfone, TFMB = 2,2′-bis(trifluoromethyl)benzidine, HFIDA = 4,4′-(hexafluoroisopropylidene)dianiline.
