The preparation of perfectly alternating poly(amide-imide)s via amide unit containing new diamine

✍ Scribed by Özdemir Özarslan; Tülay Yilmaz; Emel Yildiz; Uwe Fiedeldei; Abdülkadir Kuyulu; Attila Güngör

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 195 KB
• Volume: 35
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19970430)35:6<1149::aid-pola18>3.0.co;2-6

✦ Synopsis

The synthesis of N, N-bis(4-amino-4-biphenylene) isophthalamide (BABPI) and its applicability as a new diamine for the preparation of a series of new, high T g , perfectly alternating poly(amide-imide)s is described. BABPI was synthesized from the catalytic reduction of the corresponding dinitro compound which was prepared by the condensation of isophthaloyl chloride and 4-amino-4 -nitrobiphenyl. The modified selective reduction technique was used for the preparation of 4-amino-4-nitrobiphenyl from 4,4 -dinitro-biphenyl. Poly(amide-imide)s were synthesized by polycondensation of diamine BABPI with various commercially available aromatic dianhydrides via a conventional two-step procedure. In the first step, poly(amic-acid)s were prepared in a polar aprotic solvent, such as N-methyl pyrrolidone (NMP) at room temperature. Depending on the dianhydride used, intrinsic viscosities of poly(amicacid)s were found to range between 0.43-0.69 dL/g. Bulk thermal imidization technique was used to obtain fully imidized poly(amide-imide)s at the second step. The synthesized poly(amide-imide)s showed good thermal stability up to 320ЊC and the 10% weight loss temperatures were recorded in the range of 525-550ЊC as evidenced by thermogravimetric analysis (TGA). The glass transition temperatures were found to be between 225-235ЊC from differential scanning calorimeter (DSC) measurements.