Synthesis and Characterization of Aromatic Polyimide Containing 3,6-Diamino-9-Alkylcarbazole and Aromatic Tetracarboxylic Dianhydrides

Abstract

New soluble polyimides with inherent viscosities of 0.25–0.62 dl g−1 were synthesized from 3,6-diamino-9-alkylcarbazole and various aromatic tetracarboxylic dianhydrides by the conventional two-step method, including ring-opening polyaddition and subsequent thermally cyclodehydration. Most of the polyimides having hexyl alkyl chains were soluble in N-methylpyrrolidinone and m-cresol, while the polymers having ethyl chains were not soluble in organic solvents. The glass transition temperatures and 10% weight loss temperatures under argon of the polyimides having hexyl chains were in the ranges 232–269 °C and 485–518 °C, respectively.

Synthesis and properties of high performance polyimides derived from a novel diamine containing a N-octylcarbazole unit and two 3,5-diarylimidazole groups

“…Carbazole and its many derivatives have been widely used, both in the main-chain as building blocks and in the side-chains as pendants, in many polymers as organic photo-electronic functional materials due to their conjugated structure, intramolecular charge transfer and special photo-electronic property, high thermal and photochemical stability. [25][26][27][28][29][30][31][32] It is thus worthy exploring the feasibility of difunctionalizing the carbazole compounds, introducing them into high-performance polyimides system. The attachment of flexible alkyl side chain to the backbone of the polyimides prevent the formation of -stacking groups, disturb the planarity of aromatic units, and reduce the close packing and crystallinity.…”

Asymmetric-based novel poly(ether-imide)s: Preparation, properties, kinetics of thermal decomposition, and study electrochemical oxidation behavior by using nanocomposite paste of polymer and multi-walled carbon nanotube

“…[11][12][13] Generally, introducing bulky pendants and heteroaromatic rings into polyimides chains has been considered to be an efficient method to provide not only enhanced solubility but also good thermal and thermooxidative stability. [14][15][16] The rigidity based on the symmetry and aromaticity of the heteroaromatic rings contributes to the thermal stability, chemical stability and retention of mechanical properties of the resulting polymer at elevated temperatures. 5 However, the polarizability resulting from the heteroatom such as nitrogen atom in the imidazole ring improves the polymer's solubility in organic solvents.…”

Synthesis and characterization of new soluble and thermally stable poly(amide‐imide)s containing pendent benzimidazole moieties

“…These properties make them generally intractable or difficult to process, thus limiting their applications. Therefore, incorporating new functionalities to make polyimides more tractable without deteriorating their own excellent properties has become one important target of polyimide's chemistry 2–5. It has been generally recognized that flexible linkages6, 7 or the bulky lateral groups8–11 impart better solubility and melt‐processing characteristics compared with polymers without these linkages.…”