Photomechanically active copolyimides derived from an azobenzenediamine, a rigid dianhydride, and a flexible dianhydride
AssigneeThe United States of America as represented by the Secretary of the Air Force
InventorsLoon-Seng Tan, David Huabin Wang, Kyung Min Lee, Timothy J. White
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Abstract
Compositions of azobenzene-containing, photomechanically active, copoly(amic acids) and linear copolyimides comprising an azobenzenediamine, a rigid dianhydride, and a flexible dianhydride; and methods of making the same.
Claims14
A copolyimide having photomechanical properties and comprising an azobenzenediamine, a rigid dianhydride, and a flexible dianhydride, the copolyimide having the general formula:
- wherein Ar is at least one of 1,2,4,5-benzene (pyromellitic), 1,4,5,8-naphthalene, and 3,3′,4,4′-biphenyl;
- wherein R is at least one of —C(CF3)2—, —O—, >C═O, >SO2, —OPh-C(CF3)2—PhO—, —OPh-C(CH3)2—PhO—, >C(CF3)Ph, —O(1,3-Ph)O—, and —O(1,4-Ph)O—;
- wherein R′ and R″ are —H, —F, —Cl, or —CH3 when R′ and R″ are identical, or wherein R′ is —H and R″ is at least one of —F, —Cl, —CH3, —CF3, and —OCH3 when R′ and R″ are different;
- and
- wherein 0.05≦x≦0.50.
A copolyimide having photomechanical properties and comprising a 4,4′-diaminoazobenzene, 2,2-bis(phthalic anhydride)-1,1,1,3,3,3-hexafluoroisopropane, and pyromellitic dianhydride, and having a general formula:
- wherein R′ and R″ are —H, —F, —Cl, or —CH3 when R′ and R″ are identical, or wherein R′ is —H and R″ is at least one of —F, —Cl, —CH3, —CF3, and —OCH3 when R′ and R″ are different;
- and
- wherein 0.05≦x≦0.50.
Dependencies are inferred from the claim text.