New organic-inorganic hybrid ureasil-based polymer materials studied by PALS and SEM techniques

摘要

The new organic-inorganic materials, based on polyether chains covalently linked to a silica framework through urea bridges, referred as ureasilicates or ureasils, and semiconducting As_2S_3-ureasil composites are investigated using positron annihilation lifetime spectroscopy (PALS) and scanning electron microscopy (SEM) techniques. The results obtained show that incorporation of the As_2S_3 clusters into ureasil affects on the ortho-positronium (o-Ps) intensity or positronium formation probability and micro-/nanoscopic structure compared to the pure polymer, the effect is more essential as the loading fraction of As_2S_3 increases.