화학공학소재연구정보센터
Journal of Polymer Science Part A: Polymer Chemistry, Vol.37, No.24, 4510-4520, 1999
Synthesis and characterization of novel aromatic polyamides with polyalicyclic cardo groups
5,5-Bis[4-(4-carboxyphenoxy)phenyl]hexahydro-4,7-methanoindan (3a) and 5,5-bis[4-(4-aminophenoxy)phenyl]hexahydro-4,7-methanoindan (3b) were prepared in two main steps starting fi om the aromatic nucleophilic halogen-displacement of p-fluorobenzonitrile and p-chloronitrobenzene respectively, with 5,5-bis(4-hydroxyphenyl)hexahydro-4,7-methanoindan in the presence of potassium carbonate in N,N-dimethylformamide (DMF). Using triphenyl phosphite and pyridine as condensing agents, two series of polyamides having polyalicyclic cardo units were directly polycondensated from dicarboxylic acid 3a with various aromatic diamines, or from diamine 3b with various aromatic dicarboxylic acids in the N-methyl-2-pyrrolidone (NMP) solution containing dissolved calcium chloride. High molecular weight polyamides with inherent viscosities between 0.73 and 1.44 dL/g were obtained. All polymers were readily soluble in polar aprotic solvents such as NMP and N,N-dimethylacetamide (DMAc) and afforded transparent, flexible, and tough films by solution casting. The glass-transition temperatures (T-g) of these aromatic polyamides were in the range of 219-253 degrees C by DSC, and the 10% weight loss temperatures in nitrogen and air were above 467 and 465 degrees C, respectively. A comparative study of some polyamides with an isomeric repeat unit is also presented.