Material Behaviour: Effect of UV radiation on some polymeric networks based on vinyl ester resin and modified lignin

Some semi-interpenetrating polymer networks (semi-IPNs) based on vinyl ester resin (VER) and ammonium lignosulfonate (ALS) modified lignin were synthesized and characterized using Fourier transform-infrared (FT-IR) spectroscopy, optical microscopy (OM) and differential scanning calorimetry (DSC) techniques. VER was synthesized starting from an epoxy resin in reaction with acrylic acid. The cross-linking reaction was initiated by UV radiation. The synthesized networks showed good compatibility, due to some possible interactions between the functional groups from VER and ALS components (OH, especially). A slight effect of photostabilization of the VER was noticed, due to the ALS structures which were incorporated into the resin matrix.