In this study, surface modification of barium sulfate was investigated using several model molecules for chemical treatment: ethanesulfonic acid, butyric acid, trimethoxy(propyl) silane and phosphoric acid 2-hydroxyet...In this study, surface modification of barium sulfate was investigated using several model molecules for chemical treatment: ethanesulfonic acid, butyric acid, trimethoxy(propyl) silane and phosphoric acid 2-hydroxyethyl methacrylate. Samples were characterized by FT-IR and TGA to check the capability of these model molecules to interact with BaSO<sub>4</sub> surface. The results pointed out the presence of an organic layer around the surface after the chemical treatment even after several washings to remove all species in excess. Model molecules were grafted onto BaSO<sub>4</sub> surface and grafted density was determined. It reveals that phosphoric acid and carboxylic acid are the best candidates for the modification of BaSO<sub>4</sub> surface. Both can be used as anchoring groups to modify the hydrophilic balance of barium sulfate surface in order to avoid the formation of aggregates and to improve the compatibility of this filler within hydrophobic polymer matrix.展开更多
Aluminas supported noble metal nanoparticles have been synthesized by a new ionothermal process. The method used is easy to implement and allows obtaining catalysts in one step with high specific surface area. In addi...Aluminas supported noble metal nanoparticles have been synthesized by a new ionothermal process. The method used is easy to implement and allows obtaining catalysts in one step with high specific surface area. In addition, the metallic phase in the composites is highly dispersed and exhibits homogeneous size.展开更多
文摘In this study, surface modification of barium sulfate was investigated using several model molecules for chemical treatment: ethanesulfonic acid, butyric acid, trimethoxy(propyl) silane and phosphoric acid 2-hydroxyethyl methacrylate. Samples were characterized by FT-IR and TGA to check the capability of these model molecules to interact with BaSO<sub>4</sub> surface. The results pointed out the presence of an organic layer around the surface after the chemical treatment even after several washings to remove all species in excess. Model molecules were grafted onto BaSO<sub>4</sub> surface and grafted density was determined. It reveals that phosphoric acid and carboxylic acid are the best candidates for the modification of BaSO<sub>4</sub> surface. Both can be used as anchoring groups to modify the hydrophilic balance of barium sulfate surface in order to avoid the formation of aggregates and to improve the compatibility of this filler within hydrophobic polymer matrix.
文摘Aluminas supported noble metal nanoparticles have been synthesized by a new ionothermal process. The method used is easy to implement and allows obtaining catalysts in one step with high specific surface area. In addition, the metallic phase in the composites is highly dispersed and exhibits homogeneous size.
