| Abstract: | The reaction of pyromellitic dianhydride (1,2 : 4,5-benzenetetracarboxylic dianhydride) ( 1 ) with L - and D -alanine ( 2 L ) and ( 2 D ) leads to new monomers which were used to synthesize new copolymers. These copolymers were obtained as a product of the condensation of optical isomers of bisN-(1-chloroformylethyl)]pyromellitimides (CFEP) with poly(ethylene glycol) PEG-2000 ( 5 ). The effect of monomer structure on the structure and thermal properties of the polymers was studied using X-ray diffraction, differential scanning calorimetry and thermogravimetry. The copolymers were compared with similar copolyimides obtained previously from bis(N-chloroformylmethyl)pyromellitimide and poly(ethylene glycol), PEG 2000. The dominating effect of poly(ethylene glycol) comonomer on the crystallinity, structure and thermal stability of these new copolymers is proven. |
