M. Ueda, H. Mori
Feb 1, 1993
Citations
0
Influential Citations
11
Citations
Journal
Macromolecular Chemistry and Physics
Abstract
The direct polycondensation using the activating agent diphenyl (2,3-dihydro-2-thioxo-3-benzoxazolyl)phosphonate (1) was successfully applied to the synthesis of polyamic acid tert-butyl esters, which readily undergo AAL 1 type acid-catalyzed deesterification. Polycondensations of di-tert-butyl esters of tetracarboxylic acids with diamines were conducted in N-methyl-2-pyrrolidone in the presence of triethylamine at room temperature, producing poly(amide-ester)s with inherent viscosities up to 1,1 dL · g−1. The effects of various factors, such as solvent, amount of solvent, and amount of the activating agent, were studied. The poly(amide-ester)s are readily soluble in dipolar aprotic solvents and can be cast into uniform films from their solutions. Thermogravimetry of the polymers showed that the deesterification and imidization occur around 150–200°C, giving polyimides.