Synthesis and properties of novel aromatic polyamides containing 2-methyl-4,5-oxazolediyl structure

Synthesis and properties of aromatic polyamides containing the cyclohexane structure

“…Therefore, preparation of soluble and/or thermoplastic polyamides has been a major research interest. Many efforts have been made with the aim of making synthetic modifications of the rigid backbone by incorporating kinks of flexible linkages, [3][4][5][6] the distortion of molecular symmetry by meta-or ortho-catenated aromatic or heterocyclic units, [7][8][9][10][11][12] and the introduction of bulky groups into the polymer chain. [13][14][15][16][17][18][19][20][21][22][23][24][25] The latter method has found the widest application.…”

Preparation and Properties of Soluble Aromatic Polyamides Derived from 2,7-Triptycenedicarbonyl Dichloride

“…10 • 11 We previously reported there to be no clear difference between the properties of polyamides containing 4,5-di(l,4-phenylene)-2-methyloxazole structure in the diamine moiety and those of the corresponding isomeric polyamides having the same structure in the dicarboxylic acid unit. 12 But, Dine-Hart et al reported a polyamide derived from phthaloyl dichloride and 1,4-phenylenediamine indicated lower softening temperature than a polyamide from terephthaloyl dichloride and 1,2-phenylenediamine. 3 We previously reported that a polyamide having the 2,3-di(l ,4-phenylene)quinoxaline structure in the dicarboxylic acid unit indicated lower Tg and solubility than the corresponding isomeric polyamide containing the same structure in the diamine unit, 4 · 5 and that a polyamide having 4,4" -o-terphenyldiyl structure in the dicarboxylic acid unit showed higher Tg and lower solubility than the isomeric polyamide having the same structure in the diamine unit.…”

Synthesis of Thermally Stable Polyesters

“…This type of polyesters (Akutsu et al, , 1987(Akutsu et al, , 1990(Akutsu et al, , 1998(Akutsu et al, , 1999 are produced with heterocyclic groups in their main chain by addition of quinoxaline cycle into the polymer main chain and reaction of quinoxaline hydroxyl compound with diacids and quinoxaline amine compound with dianhydrides. Existence of these groups causes high thermoresistance of the polymer where they will not show any mass depreciatory until 300 °C.…”