Low temperature relaxations and effects on poling efficiencies of dendronized nonlinear optical side-chain polymers

Low temperature relaxations in a dendronized nonlinear optical (NLO) side-chain polymer were found to take place at more than 20 degrees C below the glass transition temperature. Relaxations of localized mobilities, removed from long range relaxations responsible for chromophore aggregation, are shown to offer new gateways for optimized acentric ordering of the chromophores. Supreme electro-optical (EO) activity was achieved by electrical poling close to the critical temperatures of localized mobilities identified as dendronized NLO side-chain relaxations. This study features, in particular, one new instrumental approach to relaxation studies of thin spin coated NLO polymer films; the shear-modulation force microscopy (SM-FM) method. Originating from scanning force microscopy (SFM), the SM-FM method grants access to the detection of low temperature relaxations in constrained thin NLO films not obtainable by conventional means. (c) 2005 American Institute of Physics.