Design and synthesis of a novel quinoxaline diamine and its polyimides with high-Tg and red color. (28th September 2019)

• Record Type: Journal Article
• Authors: Liu, Tuan-Qing; Zheng, Feng; Ding, Tong-Mei; Zhang, Shu-Yu; Lu, Qinghua
• Is Part Of: Polymer. Volume 179(2019)
• Publication Date: 2019-09-28
• Subjects: Quinoxaline -- Polyimide -- High thermal stability; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; 547.7
• DOI: 10.1016/j.polymer.2019.121612
• Languages: English
• ISSNs: 0032-3861

Abstract

Abstract: To produce high-temperature polyimide (PI) films meeting the demand of flexible-display, heteroaromatic monomers were extensively investigated. Quinoxaline is one kind of the most important N-heterocycles, which possesses pharmacological activities and thermotolerance. In this work, newly designed diamine monomer 3/2-(4-aminophenyl)-2/3-methylquinoxalin-6-amine (QMDA) was successfully synthesized. Their corresponding quinoxaline-containing PI films were prepared by cooperating QMDA with several aromatic dianhydrides, and divided into two series according to different thermal imidization procedures. The firm scaffold of quinoxaline was proved to enhance the thermal stability of the obtained PIs. The effect of final annealing temperature on molecular packing and thermal properties of the PI films was also investigated. Under higher annealing temperature, PI films were found to pack more tightly due to the formation of more cross-linkings in polymer matrix. The restriction of chian movements brought these PIs higher Tg more than 500 °C or even prevented the occurace of glass transition. Graphical abstract: Image 1 Highlights: A novel diamine derived from quinoxaline was designed and synthesized Quinoxaline polyimides exhibited high thermal stability and red color Improving final annealing temperature enhanced the thermostability of polyimides