L-phenylalanine diacid with various aromatic diamines" onerror="this.onerror=null;window.coverFallback&&coverFallback(this);">
Ionic liquids as novel solvents and catalysts for the direct polycondensation of N,N′-(4,4′-oxydiphthaloyl)-bis-L-phenylalanine diacid with various aromatic diamines