Polymer/phenanthrene-derivative host-guest systems:: Rheological, optical and thermal properties

Starting from commercially-available, polymer-based reactive resins like acrylates or unsaturated polyesters, a systematic investigation was carried out as to the influence organic dopants like phenanthrene and its derivatives have on the optical and thermal properties of the mixtures resulting from curing to the final thermoplastic polymer. The refractive index of PMMA at 633 nm can be increased, starting from 1.49 for the pure polymer, up to a value of around 1.55, and, in the case of the polyester, from 1.565 up to 1.6. The transmittance in the visible range is slightly affected at a lower dopant concentration of up to 10 wt.-%, and remains better than 80% for a sample with a thickness of 1 mm, in the range between 500 and 800 nm. An unwanted side-effect of larger dopant concentrations is to lower the glass transition temperature significantly.