Monitoring the synthesis of new polymer nanocomposites based on different polyhedral oligomeric silsesquioxanes using Raman spectroscopy

摘要

The kinetic behavior of the urethane dimethacrylate (UDMA) copolymerized and reinforced by different concentrationsof polyhedral oligomeric silsesquioxane (POSS) with methacrylic groups was studied through Raman spectroscopy.UDMA-POSS networks have been synthesized with three different types of POSS, two monofunctional POSS (1-propylmethacrylate)-heptaisobutyl substituted (HISO-POSS) and heptacyclopentyl-octasiloxan-1-yloxy) dimethylsilyl] propylmethacrylate (CPENTYL-POSS) and one octafunctional POSS-methacryl substituted (MA-POSS). In order to show the influenceof POSS on the final conversion, the hybrid systems were cured using three types of initiators which decompose at differenttemperatures: azobisisobutyronitrile (AIBN) (65 °C), benzoyl peroxide (BP) (80 °C) and di-tert-butyl peroxide (DTBP) (120 °C).The structure of the hybrid's surface was investigated by X-ray photoelectron spectroscopy (XPS) and the Tg values werecalculated from dynamic mechanical analysis (DMA) tests.