A series new thermally stable and organosoluble polyamides (PAs) 5a-f and copolyamides 10a-f with good inherent viscosities were synthesized from the direct polycondensation reaction of 1,2-bis(4-carboxyphenoxy)ethane 3 with aromatic diamines 4a-f and from the diacid 3 as a first diacid monomer and 4,4′-bis(1,3-diphenoxypropane) diacrylic acid 9 as a second diacid monomer with aromatic diamines 4a-f, respectively. The dicarboxylic acid 9 was synthesized from the two step reactions. At first 4,4′-bis(1,3-diphenoxypropane) dialdehyde 8 was synthesized from 1,3-dibromopropane 6 and 4-hydroxybenzaldehyde 7, then 4,4′-bis(1,2-diphenoxyethane) diacrylic acid 9 was synthesized from dialdehyde 8 and malonic acid in a solvent free reaction. All of the above polymers were fully characterized by 1 H NMR, Fourier transform infrared, elemental analysis, inherent viscosity, solubility tests, differential scanning calorimeter, thermogravimetric analysis, and derivative of thermogravimetric. The resulted PAs have shown admirable good inherent viscosities and thermal stability and solubility.