Thermally stable second-order nonlinear optical addition-type polyimides functionalized by diamine chromophore

✍ Scribed by Wei Wu; Dong Wang; Peiwang Zhu; Peng Wang; Cheng Ye

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 180 KB
• Volume: 37
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19990915)37:18<3598::aid-pola7>3.0.co;2-e

✦ Synopsis

A series of chromophore-functionalized polyimide prepolymers with excellent processibility were prepared by a Michael addition reaction of diamine chromophore 2 with structurally different bismaleimide (BMI) monomers. The effects of the BMI moiety's structure and thermal curing condition on glass transition temperature (T g ) and thermal stability of the polyimides were studied by DSC, TGA, and FTIR. Among the five cured polyimides, PI 3 , bearing a sulfone moiety, exhibited the highest T g and thermal decomposition temperature (T d ). Its corresponding prepolymer, PP 3 , was selected to evaluate NLO properties in a simultaneously poling and thermal polymerization process. A relatively large poling-order parameter was observed. The second-order nonlinear coefficient, d 33 , was 25 pm/V at 1064 nm fundamental wavelength. The second harmonic generation signal was almost without decay up to 170°C.