INTRODUCTION This study was designed to assess the effect of two bleaching agents on the disintegration tendency of three types of glass ionomers. MATERIALS AND METHODS A total of 90 specimens were prepared by using a split Teflon ring with an internal diameter of 5 mm and a thickness of 2 mm. The tested materials were applied and bleached according to manufacturer's instructions. Dissolution...

Ionomers are polymers which contain ionic groups that are covalently bound to the main chain. The presence of a small percentage of ionic groups strongly affects the polymer's mechanical properties. Here, we examine a new family of nanostructured ionomer films prepared from core-shell polymer nanoparticles containing acrylonitrile (AN), 1,3-butadiene (Bd) and methacrylic acid (MAA). Three new A...

We investigate the segmental and local dynamics as well as the transport of Li(+) cations in a series of model poly(ethylene oxide)-based single-ion conductors with varying ion content, using dielectric relaxation spectroscopy. We observe a slowing down of segmental dynamics and an increase in glass transition temperature above a critical ion content, as well as the appearance of an additional ...

This study evaluated the shear-bond strength of a resin-modified glass ionomer (RMGI) restorative material to a new silorane-based composite and a methacrylate-based composite in a sandwich technique with various combinations of surface treatments and bonding agents. Two composites, 2 bonding agents and 4 surface preparations were used to create 16 groups with 10 specimens each. After 24 hours ...

A photo-curable 3-arm starshape polyacrylic acid was synthesized via aqueous atom-transfer radical polymerization (ATRP), followed by tethering with 2isocyanatoethyl methacrylate. The purified polymer was used to formulate with water, comonomer and Fuji II LC filler to form a photocurable glass-ionomer cement. Compressive strength (CS) was used for evaluation. The effects of MW, comonomer, fill...

Recently, Alkaline Polymer Electrolyte Membrane Fuel Cells (APEMFCs) have been attracting worldwide attention mainly due to the prospect of using non–platinum–group metal catalysts. In addition, there is growing evidence that these fuel cells can operate with the presence of carbonate. This mini review will introduce the state–of–the–art in understanding of alkaline anion–exchange membranes (AA...

Simulations of microphase separation are carried out using the dissipative particle dynamics (DPD). By varying the concentration and temperature of resin solutions we explore mesomorphologies supported by the all-atom models. We found that for a low degree of functionalization the homogeneously distributed ionomers self-assemble into spherical micelles at solid loads below 31 wt%, subject to th...

In recent years the use of ionic polymer metal composites such as Nafion-based platinum ionomers have emerged as electroactive polymer materials with great potential for robotics and other applications. An effective activation of these materials requires understanding of their mechanism of operation. Generally, the material needs to be maintained hydrated to assure its electromechanical activit...