High dielectric constant neat polymeric film
A polymeric film and process for making same, the film comprising residues of 5(6)-amino-2-( p -aminophenyl) benzimidazole, aromatic diamine, and aromatic diacid-chloride, in the form of polymer having a polymer chain including a salt of formula I, wherein C+ is a sodium, potassium, or calcium cation, the film having a thickness of about 1 to 50 micrometers, and a dielectric constant of 4.5 or greater at 2 GHz in the absence of any particulate additives that increase the dielectric constant of the film.
1 . A polymeric film comprising residues of 5(6)-amino-2-(p-aminophenyl) benzimidazole, aromatic diamine, and aromatic diacid-chloride, in the form of polymer having a polymer chain including a salt of formula I, wherein C+ is a sodium, potassium, or calcium cation,
the film having a thickness of about 1 to 50 micrometers, and a dielectric constant of 4.5 or greater at 2 GHz in the absence of any particulate additives that increase the dielectric constant of the film.
2 . The polymeric film of claim 1 , wherein the dielectric constant is 5.0 to 6.0 at 2 GHz.
3 . The polymeric film of claim 1 having a thickness of about 1 to 12 micrometers.
4 . The polymeric film of claim 1 , wherein the aromatic diamine is paraphenylenediamine.
5 . The polymeric film of claim 1 , wherein the aromatic diacid-chloride is terephthaloyl dichloride.
6 . The polymeric film of claim 1 having a molar ratio of 5(6)-amino-2-(p-aminophenyl) benzimidazole to aromatic diamine of 30/70 to 85/15.
7 . The polymeric film of claim 6 having a molar ratio of 5(6)-amino-2-(p-aminophenyl) benzimidazole to aromatic diamine of 45/55 to 85/15.
8 . The polymeric film of claim 1 , wherein 5(6)-amino-2-(p-aminophenyl) benzimidazole is 50 mole percent or greater of the total moles of 5(6)-amino-2-(p-aminophenyl) benzimidazole and aromatic diamine present.
9 . The polymeric film of claim 1 , wherein at least 90% of the imidazole residue repeat units in the polymer are a salt of formula I.