Synthesis of thermostable polyamideimides and their properties

✍ Scribed by Huei-Hsiung Wang; Chu-Chi Chang

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 467 KB
• Volume: 60
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19960606)60:10<1579::aid-app9>3.0.co;2-g

✦ Synopsis

Thermostable polyamideimides with inherent viscosity of 1.02-1.50 dL/g were synthesized from reacting of diamine-terminated aromatic amide prepolymer with various diisocyanate terminated imide prepolymers. The imide prepolymer was prepared by using 4,4'-diphenylmethane diisocyanate to react with 3,3',4,4' benzophenonetetracarboxylic dianhydride, 3,3',4,4'-sulfonyl diphthalic anhydride, or 4,4'-oxydiphthalic anhydride using the direct onepot method to improve their solubility. Almost all of the polyamideimides were generally soluble in a wide range of organic solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, and pyridine at room temperature. Polymers with high imide content required high temperatures to dissolve. All polyamideimides had a glass transition temperature of 223-352°C and showed a 10% weight loss temperature of 415-575OC in air and 424-583OC in nitrogen atmosphere. The tensile strength, elongation at break, and initial modulus of polymer films ranged from 61 to 108 MPa, 5 to lo%, and 1.54 to 2.50 GPa, respectively. These copolymers were partly crystalline in structure as shown by X-ray patterns.