Synthesis and properties of new optically active and organosoluble poly(ester-imide)s containing L-valine moieties in the main chain by direct polycondensation reaction

Authors : Khalil FAGHIHI, Meisam SHABANIAN, Mohsen HAJIBEYGI

Pages : 279-289

Doi:10.3906/sag-1209-9

View : 13 | Download : 8

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :New optically active polyinsert ignore into journalissuearticles values(ester-imide);s insert ignore into journalissuearticles values(PEIs); containing bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic diimide in the main chain were prepared by the reaction of N,N`-insert ignore into journalissuearticles values(bicyclo[2,2,2]oct-7- ene-2,3,5,6-tetra carboxylic);-bis-L-valine 4 as a diacid monomer with various aromatic diols 5a-g in a system of tosyl chloride insert ignore into journalissuearticles values(TsCl);, pyridine insert ignore into journalissuearticles values(Py);, and N,N-dimethylformamide insert ignore into journalissuearticles values(DMF);. The reactions with TsCl were significantly promoted by controlling alcoholysis with diols, in the presence of catalytic amounts of DMF, to give a series of optically active polyinsert ignore into journalissuearticles values(ester-imide);s. The resulting new polymers were obtained in good yields and inherent viscosities, ranging between 0.36 and 0.62 dL g-1, and were characterized with FT-IR and 1H-NMR spectroscopy, including specific rotation. All of these polymers were highly organosoluble at room temperature in solvents like N,N-dimethylacetamide insert ignore into journalissuearticles values(DMAc);, N,N-dimethylformamide insert ignore into journalissuearticles values(DMF);, dimethylsulfoxide insert ignore into journalissuearticles values(DMSO);, N-methyl-2-pyrrolidone insert ignore into journalissuearticles values(NMP);, and sulfuric acid. The thermal stability of the resulting PEIs was evaluated with thermogravimetric analysis insert ignore into journalissuearticles values(TGA); and differential scanning calorimetry insert ignore into journalissuearticles values(DSC); techniques under a nitrogen atmosphere, which indicated that the residual weight percent of the polymers at 600 °C was 43.69%-60.5% and showed that they are moderately thermally stable.
Keywords : Poly ester imide, s, direct polycondensation, optically active polymers, thermal properties