Turk J Chem 31 (2007) , 113 – 124. c T ¨ UB ˙ ITAK Synthesis and Characterization of Polyimides Prepared from Optically Active (R,R) and (S,S)-1,3-bis(p-N,N- dimethylamino benzyl)-perhydrobenzimidazol-2-thi on Murat Y ˙ I ˘ G ˙ IT 1 , Turgay SEC K ˙ IN 1∗ , S¨ uleyman K ¨ OYTEPE 1 , Engin C ET ˙ INKAYA 2 1 ˙ In¨on¨u University, Faculty of Science and Literature, Chemistry Department, 44280, Malatya-TURKEY2 Ege University, Faculty of Science, Chemistry Department, 35100, ˙ Izmir-TURKEYe-mail: tseckin @inonu.e du.trReceived 10.07.2006 This paper presen ts the synthesis and characteriza tion of polyimides containing a chiral (R, R) or (S,S) 1,3-bis( p − N,N-dimethylaminobe nzyl)-pe rhy droben zimida zol-2-thion unit in the backbone. The rea ctions occu r betwe en equ imo lar amo un ts of a dia nh ydr ide and an aromat ic dimeth ylamine in the presence of the solvent N-methyl-2-pyrollidone (NMP). In this work, the chiral monomer RR and SS -1,3-bis( p − N,N-dimethylaminobenzyl)-perhydrobenzimidaz ol-2-thion were used as diamines. The polyimides obta ined were charact erized by thermogra vimet ry (TGA), differen tial thermal analy sis (DT A), differe ntia l scan ning calorimeter (DSC), infrare d spectro scop y (FT-IR), and gel permea tion chromatography (GPC). It was found that the composition of the polymer had a significant effect upon the thermal behavior of the material. Key Words: Polyimides, thermally stable polymers, dianhydride, optically active polymers. Introduction Poly imide materials have been attrac ting incr easin g attention due to their exceptio nal prope rties, whic h are differen t from those of their coun terp arts, and their p oten tial technological applicat ions. Among these materials, aromatic polyimides from pyromellitic dianhydride and diamine have generated intensive inter- est for their semiconducting and optical properties. 1−5 During the past decade, thermally stable polymers with functional groups have been attractive especially for science and technology because of their unique electronic, optical and mechanical properties and their potential applications in nano devices and functional materials. 6−8 Aromatic polyimides are a class of polymers generally not processable by conventional ther- moplast ic or hot-melt techniques. How eve r, polyimide s are exce ptionall y ther mally stable and hav e high glass transition temperatures. They are also resistant to the attack of common organic solvents . 7−19 Several authors have shown that the incorporation of chemical groups in the polymer main chain generally leads to ∗ Correspondi ng author 113
