Soluble poly(amide–imide)s prepared by one-pot solution condensation

✍ Scribed by Gordon L. Tullos; Lon J. Mathias; Michael Langsam

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 132 KB
• Volume: 37
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19990415)37:8<1183::aid-pola14>3.0.co;2-9

✦ Synopsis

A new one-pot procedure for imide-acid monomer synthesis and polymerization is reported for four new poly(amide-imide)s. Bisphenol A dianhydride (BPADA) was reacted with twice the molar amount of 3-aminobenzoic acid (3ABA) or 3-amino-4-methylbenzoic acid (3A4MBA) in 1-methyl-2-pyrrolidinone (NMP) and toluene mixture, and the amic acid intermediates cyclized in solution to give two diimide-containing dicarboxylic acid monomers. Without isolation, the diacid monomers were then polymerized with either 1,3-diaminomesitylene (DAM) or 1,5-diaminonaphthalene (1,5NAPda) using triphenyl phosphite-activation to give a series of four soluble poly-(amide-imide)s, PAI. Isolation and purification of the dicarboxylic acid monomers was not necessary for formation of high molecular weight polymers as indicated by intrinsic viscosities of 0.64 -1.04 dL/g determined in N,N-dimethylacetamide (DMAc). All of the PAI were soluble in polar aprotic solvents such as NMP, DMAc, and dimethyl sulfoxide (DMSO). Glass transition temperatures ranged from 243 to 279°C by DSC, and 5% weight loss temperatures were above 400°C in both air and nitrogen. Flexible films cast from DMAc were light yellow, transparent, and tough.