Blending of poly(benzimidazole) (PBI) with a low molecular weight ether imide model compound

Abstract

Poly(benzimidazo1e) (PBI) was solution-blended with a low molecular weight ether-imide analog to Ultem 1000. The as-cast blends were found to form one-phase structures over the whole of the composition range. By the use of optical microscopy and differential scanning calorimetry, the blends were found to phase separate on heating above the blend glass transition temperature (T,) but did not remix on cooling. It was concluded that the blends formed on room temperature casting were nonequilibrium and remained one-phase simply because they were well below Tg.

Miscible blends of nitro‐substituted polybenzimidazole and polyetherimide

“…Such desirable features of PEI can be further improved by adding PBI possessing exceptionally good thermal properties. It has been reported by Karasz and coworkers1–3, 6–9, 12 that PBI and PEI are quasi‐miscible over the entire composition. The PBI/PEI blends from solution blending in dimethylacetamide (DMAc) showed single glass‐transition temperatures ( T g 's).…”

“…For a new blend pair, poly[(2,2Ј-m-phenylene)-5,5Ј-bibenzimidazole] (polybenzimidazole, PBI) has been a notable candidate to reveal excellent thermal stability and chemical resistance. Miscible polymer blends based on PBI and aromatic polyimides (PI) [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] or the other polymers such as polycarbonates, 16 polyarylates, 17,18 polyaramides, 19 poly(vinylpyrrolidone)s, 20 and polyamic acids 21 have been reported.…”