All-aromatic polyetherimide and polyamide-imide thin films deposited by the infrared laser ablation

Abstract

The thermo-oxidative stability and molecular weight were determined for polyimide and polyamide-imide thin films, deposited by resonant infrared laser ablation (RIR-LA). RIR-LA films were deposited at various wavelengths and compared with the traditional solution-cast films using thermogravimetric analysis. The RIR-LA films showed slightly lower oxidation temperatures, but the initial weight loss temperatures were greater. Since molecular weight is directly correlated with the physical and mechanical properties of the polymer, multiangle laser light scattering was employed to ascertain the weight-average molecular weight of the polymers before and after LA. The RIR-LA films exhibited slightly reduced weight-average molecular weight. This degradation has three possible sources: bond scission during LA, reduced solvent transfer leading to lower chain extension and hydrolysis caused by the presence of atmospheric water.