Background and Aim: Minimizing the polymerization shrinkage of composite resins is a critical goals in composite restorations. Many factors affect polymerization shrinkage. This study aimed to evaluate the effect of composite resin shade on polymerization shrinkage. Materials and Methods: In this in vitro study, 14 composite discs measuring 1.5×8 mm were fabricated. The samples were prepared u...

polybutadiene nanoparticles were synthesized via batch emulsion polymerization of butadiene in the presence of potassium persulfate, disproportionate rosinate potassium cation and t-dodecyl mercaptane as initiator, emulsifier and chain transfer agent, respectively. polymerization reaction was performed at different temperatures (60, 70 and 80 °c). conversion was measured at the various time int...

Ziegler-Natta catalysis is a very important industrial process for the production of polyolefins. However, the catalysts are not well-understood at the molecular level. Yet, atomic-scale structural information is of pivotal importance for rational catalyst development. We applied a solid-state NMR/density functional theory tandem approach to gain detailed insight into the interactions between t...

The most commonly used cocatalyst species in Ziegler-Natta catalysts are aluminium alkyls. In this study we aim to find the interaction between aluminium centres of these activators and other components in the ZNC system. Initially we look at binary systems of Al-alkyl/MgCl2 and ternary systems of Al-alkyl/MgCl2/TiCl4, followed by donor containing systems. The aluminium alkyls prove to be very ...