Abstract: Abstract: A high purity diamine monomer, 3,3’5,5’-tetramethyl-4,4’-diaminodiphenyl -butyltoluene (BADP), was synthesize via one step from 2,6-dimethylaniline and benzaldehyde. The obtained diamine was subsequently employed to prepare a series of polyamides with three aromatic dicarboxylic acids by means of the Yamazaki phosphorylation polycondensation technique. The inherent viscosity of the resulting polyamides were in range of 0.57~0.84dL/g, and they exhibited an excellent solubility and optical property. They were readily soluble not only in some strong polar solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, and N,N-dimethylformamide, but also had a good solubility in some low-boiling-point solvents such as chloroform. The maximum dissolvability of them even exceeded more than 10 wt% in these solvents. The polyamide film showed high optical transparency and colorless, with a UV-Vis absorption edge between 312 nm and 345 nm. Furthermore, the polyamide also showed good thermal and mechanical properties. The temperature of 10% weight loss in air or nitrogen were higher than 380℃ and 408℃ respectively, and their glass-transition temperature (Tg) were higher than 338 ℃. The polyamide films had strengths at break at 64~81 MPa, elongations to break of 8.0%～9.2%, and initial moduli at 1.4~2.0 GPa.

Key words: 3, 3', 5, 5'-tetramethyl, synthesis, solubiity, opticaltransparency, aromatic polyamide