Low loss second-order non-linear optical crosslinked polymers based on a phosphorus-containing maleimide

A series of crossslinked organic and organic/inorganic polymers based on maleimide chemistry have been investigated for second-order non-linear optical (NLO) materials with excellent thermal stability and low optical loss. Two reactive chromophores (maleimide-containing azobenzene dye and alkoxysilane-containing azobenzene dye) were incorporated into a phosphorus-containing maleimide polymer, respectively. The selection of the phosphorus-containing maleimide polymer as the polymeric matrices provides enhanced solubility and thermal stability, and excellent optical quality. Moreover, a full interpenetrating network (IPN) was formed through simultaneous addition reaction of the phosphorus-containing maleimide, and sol-gel process of alkoxysilane dye (ASD) Atomic force microscopy (AFM) results indicate that the inorganic networks are distributed uniformly throughout the polymer matrices on a nano-scale. The silica particle sizes are well under 100 nm. Using in situ contact poling, the r(33) Coefficients of 2.2-17.0 pm/V have been obtained for the optically clear phosphorus-containing NLO materials. Excellent temporal stability (100 degreesC) and low optical loss (0.99-1.71 dB/cm; 830 nm) were also obtained for these phosphorus-containing materials. Copyright (C) 2004 John Wiley Sons, Ltd.